ICINCO 2004 Abstracts

Area 1 - Intelligent Control Systems and Optimization
Full Papers Short Papers
Area 2 - Robotics and Automation
Full Papers Short Papers
Area 3 - Signal Processing, Systems Modeling and Control
Full Papers Short Papers

Area 1 - Intelligent Control Systems and Optimization

Full Papers
Paper Nr: 6
Title:

HYBRID SOM-SVM ALGORITHM FOR REAL TIME SERIES FORECASTING
Authors:

Juan M. Górriz Sáez, E. W. Lang and Carlos G. Puntonet
Abstract: In this paper we show a new on-line parametric model for time series forecasting based on Vapnik- Chervonenkis (VC) theory. Using the strong connection between support vector machines (SVM) and Regularization theory (RT), we propose a regularization operator in order to obtain a suitable expansion of radial basis functions (RBFs) with the corresponding expressions for updating neural parameters. This operator seeks for the “attest” function in a feature space, minimizing the risk functional. Finally we mention some modifications and extensions that can be applied to control neural resources and select relevant input space.
Download
Paper Nr: 61
Title:

DECENTRALIZED ESTIMATION FOR AGC OF POWER SYSTEMS
Authors:

Xue-bo Chen, Xiaohua Li and Srdjan S. Stankovic
Abstract: A decentralized state estimation method for automatic generation control (AGC) of interconnected power systems is proposed in this paper. Based on the Inclusion Principle for linear stochastic systems, the state space model of the system is decomposed as a group of pair-wise subsystem models. The overlapping decentralized estimators and fully decentralized estimators are designed for each pair subsystems in the framework of LQG control schemes. Two types of estimators are considered for the cases of full and reduced measurement sets in the framework of system closed-loop operations. Simulation results show a high quality of the AGC scheme based on dynamic controllers with the proposed state estimators.
Download
Paper Nr: 70
Title:

AN EVOLUTIONARY ALGORITHM FOR IDENTIFICATION OF NON-STATIONARY LINEAR PLANTS WITH TIME DELAY
Authors:

Janusz Papliński and Janusz P. Papliński
Abstract: The identification of time delay in the linear plant is one of the important tasks. It is especially hard problem when the plant is non-stationary. New possibility in this field is opened by application of an evolutionary algorithm. The method of identification proposed in the paper is based on three classes of input signals. In the first case we can obtain and operate on the whole unit step response. In the second way we operate on a random signal of control, and in the last we have the stairs input signal. The identification without and with disturbances is considered.
Download
Paper Nr: 99
Title:

AN EFFECTIVE APPROACH FOR REAL-WORLD PRODUCTION PLANNING
Authors:

Jesuk Ko
Abstract: This paper shows an application of constraint logic-based approach to the realistic scheduling problem. Operations scheduling, often influenced by diverse and conflicting constraints, is strongly NP-hard problem of combinatorial optimisation. The problem is complicated further by real scheduling environments, where a variety of constraints in response are critical aspects for the application of a solution. Constraint logic programming technique well armed with the major function of constraint handling and solving mechanisms can be effectively applied to solve real-world scheduling problems. In this study, the scheduling problem addressed, based on a dye house involving jobs associated with the colouring of different fibres, is characterized by various constraints like colour precedence, dye machine allocation and time constraints. The solution procedure used takes into account a number of dye house performance measures which include on-time delivery and resource utilisation. The results indicate that constraint-based scheduling is computationally efficient in schedule generation in that a solution can be found within a few seconds. Furthermore, solutions produced always minimise the mean tardiness and maximise the utilisation of dyeing facilities.
Download
Paper Nr: 111
Title:

HIERARCHICAL MODAL CONTROL OF A NOVEL MANIPULATOR
Authors:

Clarence De Silva and Jian Zhang
Abstract: This paper focuses on the development and implementation of an intelligent hierarchical controller for the vibration control of a deployable manipulator. The emphasis is on the use of knowledge-based tuning of the low-level controller so as to improve the performance of the system. To this end, first a fuzzy inference system (FIS) is developed. The FIS is then combined with a conventional modal controller to construct a hierarchical control system. Specifically, a knowledge-based fuzzy system is used to tune the parameters of the modal controller. The effectiveness of the hierarchical control system is investigated through numerical simulation studies. Examples are considered where the system experiences vibrations due to initial disturbance at the flexible revolute joint or due to maneuvers of a deployable manipulator. The results show that the knowledge-based hierarchical control system is quite effective in suppressing vibrations induced due to the above mentioned disturbances. Results suggest that performance of the modal controller could be significantly improved through knowledge-based tuning.
Download
Paper Nr: 131
Title:

PARAMETER CONVERGENCE IN ADAPTIVE FUZZY CONTROL
Authors:

Domenico Bellomo, David Naso and Robert Babuska
Abstract: In this paper, the convergence of parameter estimates and the interactions among the two adaptive fuzzy systems constituting an indirect adaptive fuzzy controller are studied, both analytically and by means of simulations with a second-order nonlinear system. The analytical results and the simulations, performed with various initial conditions and learning rates, highlight how the interactions affect the behavior of the adaptive control scheme with regard to the control performance in terms of a tracking error, accuracy and relevance of the identified fuzzy models.
Download
Paper Nr: 134
Title:

OPTIMIZATION OF CURRENT EXCITATION FOR PERMANENT MAGNET LINEAR SYNCHRONOUS MOTORS
Authors:

Christof Roehrig
Abstract: The main problem in improving the tracking performance of permanent magnet linear synchronous motors is the presence of force ripple caused by mismatched current excitation. This paper presents a method to optimize the current excitation of the motors in order to generate smooth force. The optimized phase current waveforms produce minimal ohmic losses and maximize motor efficiency. The current waveforms are valid for any velocity and any desired thrust force. The proposed optimization method consist of three stages. In every stage different harmonic waves of the force ripple are reduced. A comparison of the tracking performance with optimized waveforms and with sinusoidal waveforms shows the effectiveness of the method.
Download
Paper Nr: 173
Title:

TABU SEARCH STRATEGIES IN SCHEDULING PROBLEM IN FLEXIBLE MANUFACTURING SYSTEM - Considering tool switches and number of setups
Authors:

Rossana Queiroz and Arthur Tórgo Gómez
Abstract: In this paper it’s investigated the impact of the Tabu List size, neighborhood generation approach and the managing of the decision variables of the Objective Function in the quality of a Tabu Search solution to the Scheduling Problem applied to a Flexible Manufacturing System. It was used a Part Scheduling Model, which starts with qualitatively different initial solutions that yields experiments in which it’s observed the Tabu List size influence in the results quality, according to the pre-defined Objective Function variables contribution. This Model creates a schedule in a Flexible Manufacturing System, considering resident tooling concepts, production turns, Part Selection, Machine Magazine Constraints and Due-dates. Numerical results show relations among neighborhood strategies and the Tabu List size behavior considering initial solutions and contribution managing of the Objective Function variables.
Download
Paper Nr: 247
Title:

A STOCHASTIC OFF LINE PLANNER OF OPTIMAL DYNAMIC MOTIONS FOR ROBOTIC MANIPULATORS
Authors:

Taha Chettibi, Abd Elfetah Hentout, Moussa Haddad and Samir Rebai
Abstract: We propose a general and simple method that handles free (or point-to-point) motion planning problem for redundant and non-redundant serial robots. The problem consists of linking two points in the operational space, under constraints on joint torques, jerks, accelerations, velocities and positions while minimizing a cost function involving significant physical parameters such as transfer time and joint torque quadratic average. The basic idea is to dissociate the search of optimal transfer time T from that of optimal motion parameters. Inherent constraints are then easily translated to bounds on the value of T. Furthermore, a stochastic optimization method is used which not only may find a better approximation of the global optimal motion than is usually obtained via traditional techniques but that also handles more complicated problems such as those involving discontinuous friction efforts and obstacle avoidance.
Download
Paper Nr: 256
Title:

FUZZY MODEL BASED CONTROL APPLIED TO IMAGE-BASED VISUAL SERVOING
Authors:

Paulo S. Goncalves, Luís Mendonça, João Caldas and João Sousa
Abstract: A new approach to eye-in-hand image-based visual servoing based on fuzzy modeling and control is proposed in this paper. Fuzzy modeling is applied to obtain an inverse model of the mapping between image features velocities and joints velocities, avoiding the necessity of inverting the Jacobian. An inverse model is identified for each trajectory using measurements data of a robotic manipulator, and it is directly used as a controller. As the inversion is not exact, steady-state errors must be compensated. This paper proposes the use of a fuzzy compensator to deal with this problem. The control scheme contains an inverse fuzzy model and a fuzzy compensator, which are applied to a robotic manipulator performing visual servoing, for a given profile of image features velocities. The obtained results show the effectiveness of the proposed control scheme: the fuzzy controller can follow a point-to-point pre-defined trajectory faster (or smoother) than the classic approach.
Download
Paper Nr: 259
Title:

CONFLICT RESOLUTION FOR FREE FLIGHT CONSIDERING DEGREE OF DANGER AND CONCESSION
Authors:

Mustafa S. Erden and Kemal Leblebicio
Abstract: In this study a conflict resolution technique based on danger and concession considerations is presented for free flight paradigm. A danger function which assigns a danger value for the conflict situation, and a concession function which assigns a concession value for the path followed by the aircraft are constructed. The danger and concession values are input to a fuzzy decision module. This module outputs the amount of deviation from the optimal path and the conflict is solved following these deviations. The method presented here is the third method we have been studying regarding to the conflict resolution problem. Its results are presented with a comparison to our other two studies.
Download
Paper Nr: 261
Title:

QUALITATIVE AND QUANTITATIVE PROBABILISTIC TEMPORAL REASONING - for Industrial Applications
Authors:

Gustavo A. Figueroa
Abstract: Many real-world domains, such as industrial diagnosis, require an adequate representation that combines uncertainty and time. Research in this field involves the development of new knowledge representation and inference mechanisms to deal with uncertainty and time. Current temporal probabilistic models become too complex when used for real world applications. In this paper, we propose a model, Temporal Events Bayesian Networks (TEBN), based on a natural extension of a simple Bayesian network. TEBN tries to make a balance between expressiveness and computational efficiency. Based on a temporal node definition, causal-temporal dependencies are represented by qualitative and quantitative relations, using different time intervals within each variable (multiple granularity). Qualitative knowledge about temporal relations between variables is used to facilitate the acquisition of the quantitative parameters. The inference mechanism combines qualitative and quantitative reasoning. The proposed approach is applied to a thermal power plant through a detailed case study, with promising results.
Download
Paper Nr: 275
Title:

A DISTURBANCE COMPENSATION CONTROL FOR AN ACTIVE MAGNETIC BEARING SYSTEM BY A MULTIPLE FXLMS ALGORITHM
Authors:

Min S. Kang and Joon Lyou
Abstract: In this paper, a design technique is proposed for a disturbance feedforward compensation control to attenuate disturbance responses in an active magnetic bearing system, which is subject to base motion. To eliminate the sensitivity of model accuracy to disturbance responses, the proposed design technique is an experimental feedforward compensator, developed from an adaptive estimation, by means of the Multiple Filtered-x least mean square (MFXLMS) algorithm. The compensation control is applied to a 2-DOF active magnetic bearing system subject to base motion. The feasibility of the proposed technique is illustrated, and the results of an experimental demonstration are shown.
Download
Paper Nr: 287
Title:

AN INTELLIGENT RECOMMENDATION SYSTEM BASED ON FUZZY LOGIC
Authors:

Xiaowei Shi
Abstract: An intelligent recommendation system for a plurality of users based on fuzzy logic is presented. The architecture of a multi-agent recommendation system is described. How the system simulates human intelligence to provide recommendation to users is explained. The recommendation system is based on the fuzzy user profile, fuzzy filtering and recommendation agents. The user profile is updated dynamically based on the feedback information. Fuzzy logic is used in fuzzy filtering to integrate different types of features together for a better simulation of human intelligence. Ambiguity problems can be solved successfully in this system, e.g., deducing whether a programme with both interesting features and uninteresting features is worth recommending or not. The application scenario shows that it is more convenient for users to find programmes of their interest with the proposed recommendation system.
Download
Paper Nr: 333
Title:

A TORQUE ESTIMATION METHOD TO AID AN INTELLIGENT MANAGEMENT SYSTEM FOR OIL WELLS AUTOMATED
Authors:

Jés Cerqueira, Alberto S. Rebouças, Flávia N. Serafim, Milena de A. Moreira, Venício R. V. Rodeiro and Amauri Oliveira
Abstract: This article presents a contribution for an oil wells intelligent management system called SGPA that nowadays manages about 700 oil wells using the rod pumping lift method at Bahia State, Brazil. The intelligent management system will be applied on oil wells using the gradual pumping method. In this oil pumping method, the torque on the rod is very important for detection of operational problems. It will be considered that the well is driven by an induction motor. A torque estimation method on rod and some results from laboratory are presented.
Download
Paper Nr: 341
Title:

SCALED GRADIENT DESCENT LEARNING RATE - Reinforcement learning with light-seeking robot
Authors:

Kary Främling
Abstract: Adaptive behaviour through machine learning is challenging in many real-world applications such as robotics. This is because learning has to be rapid enough to be performed in real time and to avoid damage to the robot. Models using linear function approximation are interesting in such tasks because they offer rapid learning and have small memory and processing requirements. Adalines are a simple model for gradient descent learning with linear function approximation. However, the performance of gradient descent learning even with a linear model greatly depends on identifying a good value for the learning rate to use. In this paper it is shown that the learning rate should be scaled as a function of the current input values. A scaled learning rate makes it possible to avoid weight oscillations without slowing down learning. The advantages of using the scaled learning rate are illustrated using a robot that learns to navigate towards a light source. This light-seeking robot performs a Reinforcement Learning task, where the robot collects training samples by exploring the environment, i.e. taking actions and learning from their result by a trial-and-error procedure.
Download
Paper Nr: 344
Title:

SOLVING THE LONGEST WORD-CHAIN PROBLEM
Authors:

Nobuo Inui, Yuji Shinano, Yuusuke Kounoike and Yoshiyuki Kotani
Abstract: The SHIRITORI game is a traditional Japanese word-chain game. This paper describes the definition of the longest SHIRITORI problem (a kind of the longest distance problem) as a problem of graph and the solution based on the integer problem (IP). This formulation requires the exponential order variables from the problem size. Against this issue, we propose a solution based on the LP-based branch-and-bound method, which solves the relaxation problems repeatedly. This method is able to calculate the longest SHIRITORI sequences for 130 thousand words dictionary within a second. In this paper, we compare the performances for the heuristic-local search and investigate the results for several conditions to explore the longest SHIRITORI problem.
Download
Paper Nr: 344
Title:

SOLVING THE LONGEST WORD-CHAIN PROBLEM
Authors:

Nobuo Inui, Yuji Shinano, Yuusuke Kounoike and Yoshiyuki Kotani
Abstract: The SHIRITORI game is a traditional Japanese word-chain game. This paper describes the definition of the longest SHIRITORI problem (a kind of the longest distance problem) as a problem of graph and the solution based on the integer problem (IP). This formulation requires the exponential order variables from the problem size. Against this issue, we propose a solution based on the LP-based branch-and-bound method, which solves the relaxation problems repeatedly. This method is able to calculate the longest SHIRITORI sequences for 130 thousand words dictionary within a second. In this paper, we compare the performances for the heuristic-local search and investigate the results for several conditions to explore the longest SHIRITORI problem.
Download
Paper Nr: 350
Title:

MODELLING THE MAN MACHINE INTERACTION - Erotetic Logic and Information Retrieval Systems
Authors:

Antonio Bellacicco and Mario Vacca
Abstract: The usual communication between man and machine is a one way interaction. It can be upgraded considering a two way interaction if the basic constituents of an information retrieval system are deeply modified in their principles. In this paper we redefine, in a syntactical way, some concepts of the erotetic logic to make them more easily computable and show how them can be used to solve some problems in the field of information retrieval systems. The result is the possibility to build more flexible and powerful information retrieval systems.
Download
Paper Nr: 359
Title:

GENETIC ALGORITHMS APPLIED TO THE OPTIMIZATION OF GASIFICATION FOR A GIVEN FUEL
Authors:

Miguel Caldas, Luisa Caldas, Viriato Semiao and Miguel Caldas
Abstract: Gasification is a well-known technology that allows for a combustible gas to be obtained from a carbonaceous fuel by a partial oxidation process (POX). The resulting gas (synthesis gas or syngas) can be used either as a fuel or as feedstock for chemical production. Recently, gasification has also received a great deal of attention concerning power production possibilities through IGCC process (Integrated Gasification Combined Cycle), which is currently the most environmentally friendly and efficient method for the production of electricity. Gasification allows for low grade fuels, or dirty fuels, to be used in an environmental acceptable way. Amongst these fuels are wastes from the petrochemical and other industries, which may vary in composition from shipment to shipment, and from lot to lot. If operating conditions are kept constant, this could result in lost of efficiency. This paper presents an application of Genetic Algorithms to optimise the operating parameters of a gasifier processing a given fuel. Two different objective functions are used: one to be used if hydrogen production is the main goal of gasification; other to be used when power/heat production is the aim of the process. Results show that the optimisation method developed is fast and simple enough to be used for on-line adjustment of the gasification operating parameters, for each fuel composition and gasification aim, thus improving the overall performance of the industrial process.
Download
Paper Nr: 363
Title:

MODEL REFERENCE CONTROL IN INVENTORY AND SUPPLY CHAIN MANAGEMENT - The implementation of a more suitable cost function
Authors:

Heikki Rasku, Hannu Koivisto, Juuso Rantala and Heikki Rasku
Abstract: A method of model reference control is investigated in this study in order to present a more suitable method of controlling an inventory or a supply chain. The problem of difficult determining of the cost of change made in the control in supply chain related systems is studied and a solution presented. Both model predictive controller and a model reference controller are implemented in order to simulate results. Advantages of model reference control in supply chain related control are presented. Also a new way of implementing supply chain simulators is presented and used in the simulations.
Download
Paper Nr: 369
Title:

AGENTS COORDINATION IN FLAT HIERARCHICAL SOCIETY-ORIENTED SYSTEMS
Authors:

Mihaela Cistelecan
Abstract: The paper proposes a framework for engineering a coherent society-oriented system using the concept of sliding-mode control from systems theory. The agents are coordinated through local control laws using a switching logic related to the sliding manifolds. The sliding manifolds stand for sub-plans and therefore they are updated every time a change in planning is required. The agents have the ability of self-adaptation by adjusting the structure of the sliding manifolds. The design is performed using tools from the algebraic framework. We also address the problem of deriving the sliding manifolds from the given specifications.
Download
Paper Nr: 393
Title:

TUNING THE PARAMETERS OF A CLASSIFIER FOR FAULT DIAGNOSIS - Particle Swarm Optimization vs Genetic Algorithms
Authors:

Cosmin D. Bocaniala and José Sa Da Costa
Abstract: This paper presents a comparison between the use of particle swarm optimization and the use of genetic algorithms for tuning the parameters of a novel fuzzy classifier. In previous work on the classifier, the large amount of time needed by genetic algorithms has been significantly diminished by using an optimized initial population. Even with this improvement, the time spent on tuning the parameters is still very large. The present comparison suggests that using particle swarm optimization may improve considerably the time needed for tuning the parameters. In this way, the fuzzy classifier becomes suitable for real world application. The result is validated by application to a fault diagnosis benchmark.
Download
Paper Nr: 394
Title:

ITERATIVE LINEAR QUADRATIC REGULATOR DESIGN FOR NONLINEAR BIOLOGICAL MOVEMENT SYSTEMS
Authors:

Weiwei Li and Emanuel Todorov
Abstract: This paper presents an Iterative Linear Quadratic Regulator (ILQR) method for locally-optimal feedback control of nonlinear dynamical systems. The method is applied to a musculo-skeletal arm model with 10 state dimensions and 6 controls, and is used to compute energy-optimal reaching movements. Numerical comparisons with three existing methods demonstrate that the new method converges substantially faster and finds slightly better solutions.
Download
Paper Nr: 396
Title:

A COMBINED APPROACH TO FAULT DIAGNOSIS IN DYNAMIC SYSTEMS - Application to the Three-Tank Benchmark
Authors:

Luis Palma, Fernando Coito and Rui Silva
Abstract: This paper presents a combined approach to fault diagnosis in discrete-time dynamic systems. The approach integrates classical and soft computing techniques. The typical methods based on signal models, and process models for residual generation are considered: parity equations, observers and parameter estimation. The role of integration of classical and intelligent techniques is enhanced. The performance of the proposed approach is analysed with application to a typical nonlinear feed-water system – the three-tank benchmark. The three typical fault scenarios (actuator and component faults) defined in the benchmark problem are tackle in this work.
Download
Paper Nr: 403
Title:

DYNAMIC ROUTING AND QUEUE MANAGEMENT VIA BUNDLE SUBGRADIENT METHODS
Authors:

Almir Mutapcic, Majid Emami and Keyvan Mohajer
Abstract: In this paper we propose a purely distributed dynamic network routing algorithm that simultaneously regulates queue sizes across the network. The algorithm is distributed since each node decides on its outgoing link flows based only on its own and its immediate neighbors' information. Therefore, this routing method will be adaptive and robust to changes in the network topology, such as the node or link failures. This algorithm is based on the idea of bundle subgradient methods, which accelerate convergence when applied to regular non-differentiable optimization problems. In the optimal network flow framework, we show that queues can be treated as subgradient accumulations and thus bundle subgradient methods also drive average queue sizes to zero. We prove the convergence of our proposed algorithm and we state stability conditions for constant step size update rules. The algorithm is implemented using Matlab and its performance is analyzed on a test network with varying data traffic patterns.
Download
Paper Nr: 407
Title:

AN LMI OPTIMIZATION APPROACH FOR GUARANTEED COST CONTROL OF SYSTEMS WITH STATE AND INPUT DELAYS
Authors:

Olga Kosmidou, Y.S. Boutalis and Ch. Hatzis
Abstract: The robust control problem for linear systems with parameter uncertainties and time-varying delays is examined. By using an appropriate uncertainty description, a linear state feedback control law is found ensuring the closed-loop system's stability and a performance measure, in terms of the guaranteed cost. An LMI objective minimization approach allows to determine the ”optimal” choice of free parameters in the uncertainty description, leading to the minimal guaranteed cost.
Download
Paper Nr: 409
Title:

USING A DISCRETE-EVENT SYSTEM FORMALISM FOR THE MULTI-AGENT CONTROL OF MANUFACTURING SYSTEMS
Authors:

Guido Maione and David Naso
Abstract: In the area of Heterarchical Manufacturing Systems Modeling and Control, a relatively new paradigm is that of Multi-Agent Systems. Many efforts have been made to define the autonomous agents concurrently operating in the system and the relations between them. But few results in the current literature define a formal and unambiguous way to model a Multi-Agent System, which can be used for the real-time simulation and control of flexible manufacturing environments. To this aim, this paper extends and develops some results previously obtained by the same authors, to define a discrete event system model of the main distributed agents controlling a manufacturing system. The main mechanism of interaction between three classes of agents is presented.
Download
Paper Nr: 430
Title:

FROM UML TOWARDS PETRI NETS TO SPECIFY AND VERIFY
Authors:

Thouraya Bouabana-tebibel and Mounira Belmesk
Abstract: UML nowadays, has emerged as the industry standard for object-oriented modeling. However, it still lacks a well-defined semantic base enabling it to perform formal verification and validation tasks. Our goal being to provide system designers a life cycle of software development integrating conviviality and rigor, we propose a methodology to specify, verify and validate using UML. This methodology is based on a technique which derives colored Petri nets from UML class, statechart and collaboration diagrams. The approach that we propose associates the formalization of the object dynamics to the formalization of the object behavior. A case study is provided to illustrate this technique.
Download
Paper Nr: 451
Title:

INTELLIGENT ELECTRIC DRIVE SYSTEM - A mechatronics approach
Authors:

Guy R. Dunlop
Abstract: Drive efficiency is an important consideration in most robotic applications. A hybrid controller for permanent magnet DC motors has been developed to control the current, and hence the output torque of the motor. An H bridge is used to provide the basic PWM voltage to the motor, and the controller switches the bridge between bipolar and unipolar modes in order to minimise the switching losses within the bridge and motor, and also to minimise the electromagnetic interference. The first application presented is for a walking robot, and the second is for a dexterous robotic hand. In both cases, control is obtained from a voltage sourced inverter by means of a tight control loop that uses position readings to infer velocity so that a full DC motor model can be utilised in the control computer. For the dexterous hand, current control is by model prediction to avoid the need for direct measurement. The controller and communications are contained within a small programmable system on a chip which together with a dual H bridge driver is integrated into small circuit board that is used for distributed control within the hand.
Download
Short Papers
Paper Nr: 53
Title:

HBP: A NOVEL TECHNIQUE FOR DYNAMIC OPTIMIZATION OF THE FEED-FORWARD NEURAL NETWORK CONFIGURATION
Authors:

Wan W. Lin, Kang A. Wong and Tharam Dillon
Abstract: The novel Hessian-based pruning (HBP) technique to optimize the feed-forward (FF) neural network (NN) configuration in a dynamic manner is proposed. It is then used to optimize the extant NNC (Neural Network Controller) as the verification exercise. The NNC is designed for dynamic buffer tuning to eliminate buffer overflow at the user/server level. The HBP optimization process is also dynamic and operates as a renewal process within the service life expectancy of the target FF neural network. Every optimization renewal cycle works with the original NN configuration. In the cycle all the insignificant NN connections are marked and then skipped in the subsequent operation before the next optimization cycle starts. The marking and skipping operations together characterize the dynamic virtual pruning nature of the HBP. The interim optimized NN configuration produced by every HBP cycle is different, as the response to the current system dynamics. The verification results with the NNC indicate that the HBP technique is indeed effective because all the interim optimized/pruned NNC versions incessantly and consistently yield the same convergence precision to the original NNC predecessor, and with a shorter control cycle time.
Download
Paper Nr: 64
Title:

AN INSTRUMENT CONTROL SYSTEM USING PREDICTIVE MODELLING
Authors:

Geoffrey Holmes and Dale Fletcher
Abstract: We describe a system for providing early warning of possible error to an operator in control of an instrument providing results in batches from samples, for example, chemical elements found in soil or water samples. The system has the potential to be used with any form of instrument that provides multiple results for a given sample. The idea is to train models for each measurement, using historical data. The set of trained models are then capable of making predictions on new data based on the values of the other measurements. This approach has the potential to uncover previously unknown relationships between the measurements. An example application has been constructed that highlights the difference of the actual value for a measurement from its predicted value. The operator is provided with sliders to attenuate the sensitivity of the measurement perhaps based on its importance or its known sensitivity.
Download
Paper Nr: 132
Title:

RESISTANCE SPOT WELDING PROCESS IDENTIFICATION AND INITIALIZATION BASED ON SELF-ORGANIZING MAPS
Authors:

Heli Junno, Perttu Laurinen, Eija Haapalainen, Lauri Tuovinen, Juha Röning, Dietmar Zettel, Daniel Sampaio, Norbert Link and Michael Peschl
Abstract: Resistance spot welding is used to join two or more metal objects together, and the technique is in widespread use in, for example, the automotive and electrical industries. This paper discusses both the identification of different spot welding processes and the process initialization parameters leading to high-quality welding joints. In this research, self-organizing maps (SOMs) were used, and optimal features for the training parameters were sought. According to the results, processes can be classified by specific features. When introducing new data to trained SOMs, the welding operator can visually identify similar processes. After process identification, the most similar process is retrieved and a self-organizing map is trained for this specific process. The initialization parameters leading to successful welds in that process can thus be identified, which means that the manufacturers can use them to initialize their welding machines.
Download
Paper Nr: 179
Title:

BEST-ACTION PLANNING FOR REAL-TIME RESPONSE - An approach in ORICA
Authors:

Tariq A. Omar, Ana Simonet and Michel Simonet
Abstract: A planner for real-time response aims at building a plan to safely guide the world to its goal state by guaranteeing response deadlines. Ideally, it should find the paths most suitable for guaranteeing real-time behaviour and goal achievement. To achieve this ideal behaviour, it must possess maximum information about the world behaviour and be able to plan the responses of the system under-control to its advantage. It should be able to reason about one path with respect to the other, based on the execution duration, the amount of resources used and the system safety. In this paper, we present the ORICA (OSIRIS1 real-time intelligent control architecture) real-time response planner, which builds plans that permit the real-time system to strive to achieve its goal in un-guaranteed environment behaviour, while still ensuring system safety. It does heuristic reasoning for comparison of different paths when a choice of path is possible.
Download
Paper Nr: 250
Title:

DISTRIBUTED LOAD BALANCING OF DISTRICT HEATING SYSTEMS: A SMALL-SCALE EXPERIMENT
Authors:

Fredrik Wernstedt and Paul Davidsson
Abstract: We present results from an experiment where the effects of automatic flow control at a single substation is compared to automatic cooperative concurrent flow control at multiple substations. The latter approach is made possible by equipping individual substations with some computing power and integrating them into a communications network. Software agents, whose purpose is to cooperate with other software agents (substations) and to invoke reductions, are connected to each substation. The experiment show that it is possible to automatically load balance a small district heating network using agent technology, e.g., to perform automatic peak clipping and load shifting.
Download
Paper Nr: 254
Title:

DYNAMIC BOOKING POLICY FOR AIRLINE SEAT INVENTORY CONTROL
Authors:

Kristine Rozite, Nicholas Nechval, Konstantin N. Nechval and Edgars K. Vasermanis
Abstract: A dynamic booking policy for multiple fare classes that share the same seating pool on one leg of an airline flight, when seats are booked in a nested fashion and when lower fare classes book before higher ones, is determined. The dynamic policy of airline booking makes repetitive use of an optimal static policy over the booking period, based on the most recent demand and capacity information. It allows one to allocate seats dynamically and anticipatory over time.
Download
Paper Nr: 274
Title:

A GROUP DECISION SUPPORT SYSTEM - A description on models and modules in GDSS based on cooperative MAS
Authors:

Weiren Shi, Jiang Daoping, Liang Yonglin and Chen Jing
Abstract: GDSS is a popular and attractive topic in decision field. It is reasonable to introduce multi-Agent technology and methodology into GDSS because they are both distributed systems and support interaction in group members. We look at the development of GDSS as being a process of putting together a coordinated workflow of collaborating Agents that is able to support a problem-solving process. We propose models to describe character of Agents and issue in GDSS, define the modules of group-decision as cognitive, group organizing, decision-making by cooperation, feedback and adjust decision, conduce consensus decision by negotiation, knowledge management and repository evolution, and explain the process of every part.
Download
Paper Nr: 288
Title:

WHEELED VEHICLES CLASSIFICATION USING RADIAL BASE FUNCTION NEURAL NETWORK - Intelligent Control Systems and Optimization
Authors:

Jerzy Jackowski and Roman Wantoch-rekowski
Abstract: The paper presents the problem of using neural network for military vehicle classification on the basis of ground vibration. One of the main element of the system is a unit called geophone. This unit allows to measure amplitude of ground vibration in each direction for certain period of time. The value of amplitude is used to fix the characteristic frequencies of each vehicle. If we want to fix the main frequency it is necessary to use Fourier transform. In this case the fast Fourier transform FFT was used. Because the neural network (Radial Basis Function network) was used, the learning set has to be prepared. Please find attached the results of using RBF neural network such as: example of learning, validation and test sets, structure of the networks and learning algorithm, learning and testing results.
Download
Paper Nr: 326
Title:

A REVIEW OF ADVANCES IN ECONOMIC DISPATCH USING ARTIFICIAL NEURAL NETWORKS
Authors:

Tahir Nadeem, Aftab Ahmad and Aftab Ahmad
Abstract: Economic Dispatch Problem (EDP) has been discussed with reference to the developments based on Artificial Neural Networks (ANN) approaches. A selected survey / overview on Economic Dispatch using Artificial Neural Network within the IEE/IEEE publications frame work have been presented.
Download
Paper Nr: 338
Title:

AN HORIZONTAL APPROACH TO BATCH SCHEDULING - Using the Simultaneous Manufacturing philosophy
Authors:

Ana Almeida, Carlos Ramos and Sílvio Silva
Abstract: This paper is concerned with Batch Scheduling in job-shop like manufacturing systems. The Horizontal Scheduling approach is used, assuming that full scheduling of a simple or complex job, based on the job routing network of operations, from the first operation to the last, is performed before another job is considered for scheduling, having in consideration existing manufacturing processors and their availability. We follow this approach because we aim at compressing job flow time to a minimum as a strategy to meeting job due dates. To further enhance this objective the idea behind Simultaneous Manufacturing through, the widespread use of batch overlapping with Job Scheduling Patterns, which proved particularly effective in reducing job throughput time, maintaining operating simplicity and requiring reduced coordination
Download
Paper Nr: 352
Title:

MULTI-AGENTS BASED REFERENCE MODEL FOR FAULT MANAGEMENT SYSTEM IN INDUSTRIAL PROCESSES
Authors:

Mariela Cerrada-lozada, Juan Cardillo, Jose Aguilar and Raúl Faneite
Abstract: Nowadays, industrial necessities claims global management procedures integrating information systems in order to manage and to use the controlled-processes information and thus, to assure a good process behaviour. These aspects aim to the development of fault detection and diagnosis systems and making-decision systems. In this work, a reference model for fault management in industrial processes is proposed. This model is based on a generic framework using multi-agent systems for distributed control systems; in this sense, the fault management problem is viewed like a feedback control process and the actions are related to the making-decision in the preventive maintenance task scheduling and the running of preventive and corrective specific maintenance tasks.
Download
Paper Nr: 358
Title:

FUZZY CONTROL FOR FABRICS DRYING ON AN INDUCTION HEATED ROTATING CYLINDER: Experimental results
Authors:

Perez Sergio, Zulay Niño, Normand Thérien and Arthur D. Broadbent
Abstract: The removal of water from materials in textile industry and pulp and paper industries requires a high-energy consumption, increasing significantly the operating costs. Nevertheless, electromagnetic induction heating is an alternative with considerable potential for the thermal treatment of materials. Specifically, heating the surface of a metallic cylinder by electromagnetic induction has opened up a range of applications for continuos heating, pre-drying and drying of fibrous web. Otherwise, these news electrotechnologies with industrial applications have to be used under controlled operational conditions. The past few years witnessed a rapid growth in the use of fuzzy logic controllers for the control of processes, which are complex and ill defined. These control systems are inspired by the approximate reasoning capabilities of the process operator. The purpose of this paper is to improve and apply an digital control structure on the basis of fuzzy logic technique for the textile drying using a rotational cylinder heated by electromagnetic induction, manipulating the power supply to the inductors to control the exit humidity of the web. The proposed fuzzy logic controller was tested experimentally in a dryer pilot-scale plant and the results show the capability of the controller to reach the set point initially fixed at 20 g water/100 g dry fabric. Once reached the set point, continuing the trial, steps changes of the web-cylinder contact surface and the set point were done and the results shows the capacity of the proposed fuzzy logic controller in both perturbations.
Download
Paper Nr: 371
Title:

DATA SECURITY CONSIDERATIONS IN MODERN AUTOMATION NETWORKS
Authors:

Mikko Salmenperä and Jari Seppälä
Abstract: The automation manufacturing business has reached its turning point and manufacturers are forced to create new business areas. Their expertise about field devices will be the source for future growth of automation industry. This includes monitoring, maintenance, data analysis and process tuning which all require good remoting capabilities in order to be successfully and cost efficiently applied as a service for production plants. This trend builds new challenges for automation services support systems. They are forced to adapt into global business model where customers utilise network connections from old modem lines into modern mobile communication networks. ”Information is power” therefore securing production and other process related information systems in modern automation networks is becoming a necessity. The resent headlines have proven that automation systems are becoming more vulnerable with the inclusion of standard office and Internet technologies into the automation networks. The only way to meet the security challenges in a global scale is to build the the connectivity using secure-by-desing methodology.
Download
Paper Nr: 380
Title:

HOW TO ESCAPE TRAPS USING CLONAL SELECTION ALGORITHMS
Authors:

Vincenzo Cutello, G. Narzisi, Giuseppe Nicosia, Mario Pavone and Giuseppe Sorace
Abstract: This paper presents an experimental study on clonal selection algorithms (CSAs) to optimize simple and complex trap functions. Several settings of the proposed immune algorithms were tested in order to effectively face such a hard computational problem. The key feature to solve the trap functions, hence escape traps, is the usage of the hypermacromutation operator couple with a traditional perturbation immune operator. The experimental results show that the CSAs we designed are very competitive with the best algorithms in literature.
Download
Paper Nr: 405
Title:

EVOLUTIONARY APPROACH FOR DYNAMIC SCHEDULING IN MANUFACTURING
Authors:

Ana Madureira, Carlos Ramos and Sílvio Silva
Abstract: This paper presents a simple and general framework exploring the potential of evolutionary algorithms, which is of practical utility, embedded in a simple framework to solve difficult problems in dynamic environments. The proposed evolutionary approach is in line with reality and away from the approaches that deal with static and classic or basic Job-Shop scheduling problems. In fact, in real world, where problems are essentially of dynamic and stochastic nature, the traditional methods or algorithms are of very little use. This is the case with most algorithms for solving the so-called static scheduling problem for different setting of both single and multi-machine systems arrangements. This reality, motivated us to concentrate on tools, which could deal with such dynamic, disturbed scheduling problems, both for single and multi-machine manufacturing settings, even though, due to the complexity of these problems, optimal solutions may not be possible to find. We decided to address the problem drawing upon the potential of Genetic Algorithms to deal with such complex situations.
Download
Paper Nr: 408
Title:

AN LMI-BASED GENETIC ALGORITHM FOR GUARANTEED COST CONTROL
Authors:

George Papakostas, Olga Kosmidou and I.E. Antonakis
Abstract: In this paper a new approach for the Guaranteed Cost Control Problem (GCCP) is presented, using two efficient tools, Linear Matrix Inequalities (LMIs) and Genetic Algorithms (GAs). A linear system with parametric uncertainty is considered for which a control law is to be found, minimizing a performance index. In a previous paper, an efficient method has been presented by using an LMI optimisation technique. A combined use of LMIs and GAs is proposed in the present approach that allows further improvement of the design procedure.
Download
Paper Nr: 428
Title:

A DECENTRALIZED ROUTE GUIDANCE ALGORITHM IN URBAN TRANSPORTATION NETWORKS
Authors:

Adacher Ludovica and Gaia Nicosia
Abstract: In the last decades, due to the increasing car traffic and the limited capacity of urban networks, algorithms for traffic management and route guidance are becoming more and more important. GPS technology can be used for fleet monitoring in urban or suburban areas, from a central monitoring station and may provide useful information concerning the movement of all vehicles. Current route guidance systems are simple from an algorithmic point of view (they compute shortest paths to the destination), but they have to deal with huge size networks. For this reason, a decentralized approach, in which each vehicle independently calculates its own route, is desirable. Naturally, to limit the congestion due the vehicles decisions, an estimate on the different possible routes is required. Hence, we propose a decentralized algorithm in which each vehicle computes its own route on the basis of the traffic information provided by the reference station. Moreover, we propose a method for forcing vehicles to choose different paths and for informing the reference station on the routes of all vehicles, so that traffic forecast is updated.
Download

Area 2 - Robotics and Automation

Full Papers
Paper Nr: 32
Title:

AIRCRAFT ELECTRICAL MONITORING & FAULT DETECTION
Authors:

George Kusic
Abstract: Fault detection and electrical system monitoring (management) for aircraft/spacecraft dc or 400 Hz electrical systems is presented. Real-time ‘snapshot’ data is collected from current and voltage measurement transducers on radial or loop aircraft electrical system and introduced into a State Estimator. The State Estimator ‘smoothes’ the data, detects bad transducers, and calculates the best estimate of the voltage and phase angle at busses of the network, i.e., the ‘state’ of the network. Experimental results of estimation and fault detection are presented.
Download
Paper Nr: 101
Title:

PREVISUALIZATION IN ROBOTICS: AN ATOMIC APPROACH
Authors:

Mauno Rönkkö
Abstract: In this paper, we discuss use of previsualization in robotics. In previsualization, a computer animates a highly underspecified model; thus, helping the designers to detect missing components. When applied to robotics, previsualization should reveal detailed dynamics that is not explicitly specified in the model. In particular, it should reveal interaction dynamics of the physical components. Such a requirement is non-trivial. In this paper, we investigate an atomic approach that uses emergent dynamics to reveal the interaction dynamics. The approach is based on use of atoms that obey simple, compositional interaction laws. The laws produce emergent interaction dynamics for physical components composed of atoms. As the main contribution, we shall illustrate how the atomic approach, despite its simplicity, captures compactly non-trivial settings, and reveals effortlessly intricate dynamics that are otherwise considered too laborious for modelling.
Download
Paper Nr: 133
Title:

HYBRID CONTROL DESIGN FOR A ROBOT MANIPULATOR IN A SHIELD TUNNELING MACHINE
Authors:

Robert Babuska, Jelmer Braaksma, Ben Klaassens and Cees de Keizer
Abstract: In a novel shield tunneling method, the tunnel lining is produced by an extrusion process with continuous shield advance. A robotic manipulator is used to build the tunnel supporting formwork, consisting of rings of steel segments. As the shield of the tunnel-boring machine advances, concrete is continuously injected in the space between the formwork and the surrounding soil. This technology requires a fully automated manipulator, since potential human errors may jeopardize the continuity of the tunneling process. Moreover, the environment is hazardous for human operators. The manipulator has a linked structure with seven degrees of freedom and it is equipped with a head that can clamp the formwork segment. To design and test the controller, a dynamic model of the manipulator and its environment was first developed. Then, a feedback-linearizing hybrid position-force controller was designed. The design was validated through simulation in Matlab/Simulink. Virtual reality visualization was used to demonstrate the compliance properties of the controlled system.
Download
Paper Nr: 140
Title:

TRACKING OF EXTENDED CROSSING OBJECTS USING THE VITERBI ALGORITHM
Authors:

Andreas Kraeussling, Frank E. Schneider, Andreas Kraeussling and Andreas Kraeussling
Abstract: Tracking, which means determining the positions of the humans in the surrounding, is one of the goals in the field of mobile robots that operate in populated environments. This paper is concerned with the special problem of tracking expanded objects under such constraints. A solution in form of a Viterbi based algorithm, which can be useful for real–time systems, is presented. Thus a Maximum–a–posteriori (MAP) filtering technique is applied to perform the tracking process. The mathematical background of the algorithm is proposed. The method uses the robots’ sensors in form of laser range finders and a motion and observation model of the objects being tracked. The special problem of the crossing of two expanded objects is considered. The mathematical background for this problem is enlightened and a solution for it in form of a heuristic algorithm is proposed. This algorithm is tested on simulated and real data.
Download
Paper Nr: 252
Title:

MOCONT LOCATION MODULE: A CONTAINER LOCATION SYSTEM BASED ON DR/DGNSS INTEGRATION
Authors:

Joseba Landaluze, Ana Martinez, Victoria del Río, Carlos F. Nicolás and José M. Ezkerra
Abstract: The problem of identifying and adequately positioning containers in the terminal yard during handling with Reach Stackers still remains to be solved in an appropriate manner, while this is extremely important in making the identification and positioning operations automatic. A precise knowledge in the Terminal Operating System (TOS) of such data in Real Time would have considerable economic impact on the logistic treatment of operations. The MOCONT system sets out to provide a solution to this lack. In particular, the MOCONT Location Module establishes the position of the container in the yard while it is being handled by a Reach Stacker. This system is based on the integration of the Differential Global Navigation Satellite System (DGNSS) with a Dead Reckoning (DR) inertial system. This article presents the general characteristics of the MOCONT Location Module, its structure, and the structure of data fusion, besides some results obtained experimentally.
Download
Paper Nr: 266
Title:

AVOIDING VISUAL SERVOING SINGULARITIES USING A COOPERATIVE CONTROL ARCHITECTURE
Authors:

Nicolas Garcia Aracil, Luis Payá, Jose M. Azorin, Jose M. Sabater, Ramon Ñeco and C. Pérez
Abstract: To avoid the singularities of an image-based visual control of an industrial robot (Mitsubishi PA-10), a simple and efficient control law which combines the information of two cameras in a cooperative way has been developed and tested. One of this cameras is rigidly mounted on the robot end-effector (eye-in-hand configuration) and the other one observes the robot within its workspace (eye-to-hand configuration). The system architecture proposed allows us to control the 6 dof of an industrial robot when typical problems of image-based visual control techniques are produced.
Download
Paper Nr: 268
Title:

POSITION CONTROL OF AN ELECTRO-HYDRAULIC SERVOSYSTEM - A non-linear backstepping approach
Authors:

Claude Kaddissi, Jean-pierre Kenné and Maarouf Saad
Abstract: This paper studies the control of an electro-hydraulic servosystem using a non-linear backstepping based approach. These systems are known to be highly non-linear due to many factors as leakage, friction and especially the fluid flow expression through the servo-valve. Another fact, often neglected or avoided, is that such systems have a non-differentiable mathematical model for bi-directional applications. All these facets are pointed out in the proposed model of this paper. Therefore, the control of this class of systems should be based on non-linear strategies. Many experiments showed the failure of classic control with electro-hydraulic systems, unless operating in the neighborhood of a desired value or reference signal. The backstepping is used here to overcome all the non-linear effects. The model discontinuity is solved in this paper, by approximating the non-differentiable function by a sigmoid, so that the backstepping could be used without restrictions. In fact, simulation results show the effectiveness of the proposed approach in terms of guaranteed stability and zero tracking error.
Download
Paper Nr: 279
Title:

MOBILE ROBOT LOCALIZATION BY CONSTRAINT PROPAGATION ON INTERVALS
Authors:

Clerentin Arnaud, Delahoche Laurent, Delafosse Mélanie and Eric Brassart
Abstract: This paper proposes to use constraint propagation on intervals to solve the mobile robot localization problem. The mobile robot is equipped with an exteroceptive sensor and dead-reckoning. These two sensors give imprecise data that are modelled by intervals. Our localization strategy is based on multi target tracking. To this aim, the data given by our two sensors are fused by constraint propagation. So, at the end of the localization process, we get a 3-D subpaving which is supposed to contain the robot’s position in a guaranteed way. The localization imprecision is naturally managed by our method.
Download
Paper Nr: 324
Title:

SKILL ACQUISITION PROCESS OF A ROBOT-BASED AND A TRADITIONAL SPINE SURGERY
Authors:

Meike Jipp, Werner W. Wittmann, Peter P. Pott, Achim Wagner and Essameddin Badreddin
Abstract: Technological progress greatly revolutionizes medicine. Robots give the opportunity to reach greater accuracy and thus improve the medical outcome. The results of a surgical intervention profoundly depend on the robot system and on the training state of the operator. Since the learning of a surgical intervention can be influenced by the complexity of the system, these interconnections are investigated with psychological methods. Therefore, the skill acquisition process of a robot-based surgery is compared to a traditional spine surgery. The usage of an appropriate robot shortens the learning curve of a spine surgery due to a decreased complexity and reduces the impact of the surgeons’ psychomotor abilities on the surgery’s outcome. For the design of a surgical system, different realizations must be tested in advance regarding their cognitive workload to avoid training costs learning the operation of the system, afterwards. The methods used are not restricted to surgical robotics.
Download
Paper Nr: 327
Title:

PARTIAL VIEWS MATCHING USING A METHOD BASED ON PRINCIPAL COMPONENTS
Authors:

Santiago Salamanca, Carlos Cerrada, Antonio Adan and Miguel Adán Oliver
Abstract: This paper presents a method to estimate the pose (position and orientation) associated to the range data of an object partial view with respect to the complete object reference system. A database storing the principal components of the different partial views of an object, which are generated virtually, is created in advance in order to make a comparison between the values computed in a real view and the stored values. It allows obtaining a first approximation to the searched pose transformation, which will be afterwards refined by applying the Iterative Closest Point (ICP) algorithm. The proposed method obtains very good pose estimations achieving very low failure rate, even in the case of the existence of occlusions. The paper describes the method and demonstrates these conclusions by presenting a set of experimental results obtained with real range data.
Download
Paper Nr: 330
Title:

TOWARDS A CONCEPTUAL FRAMEWORK- BASED ARCHITECTURE FOR UNMANNED SYSTEMS
Authors:

Norbert Oswald
Abstract: Future unmanned aerial systems demand capabilities to perform missions automatically to the greatest possible extent. Missions like reconnaissance, surveillance, combat, or SEAD usually consist of recurring phases and contain resembling or identical portions such as autonomous flight control, sensor processing, data transmission, communication or emergency procedures. To avoid implementing many similar singular solutions, a systematic approach for the design of an unmanned avionic software architecture is needed. Current approaches focus on a coarse system design, do not integrate off-the-shelf middleware, and do not consider the needs for having on-board intelligence. This paper presents a reference software architecture to design and implement typical missions of unmanned aerial vehicles based on a CORBA middleware. The architecture is composed of identical components and rests upon the peer-to-peer architectural style. It describes the internal structure of a single component with respect to autonomous requirements and provides a framework for the rapid development and implementation of new components. The framework separates functionality and middleware by hiding ORB specific statements from components. Experimental tests simulating a reconnaissance mission using various ORB implementations indicate the benefits of having an architectural design supporting multi-lingual multi-process distributed applications.
Download
Paper Nr: 342
Title:

POSITION AND ORIENTATION CONTROL OF A TWO-WHEELED DIFFERENTIALLY DRIVEN NONHOLONOMIC MOBILE ROBOT
Authors:

Adelardo Medeiros, Antônio Araújo, Frederico Vieira and Pablo Alsina
Abstract: This paper addresses the dynamic stabilization problem of a two-wheeled differentially driven nonholonomic mobile robot. The proposed strategy is based on changing the robot control variables from x, y and Ɵ to s and Ɵ, where s represents the robot linear displacement. Using this model, the nonholonomic constraints disappear and we show how the linear control theory can be used to design the robot controllers. This control strategy only needs the robot localization (x, y, Ɵ), not requiring any velocity measurement or estimation. The complete derivation of the control strategy and some simulated results are presented.
Download
Paper Nr: 348
Title:

STEREOVISION APPROACH FOR OBSTACLE DETECTION ON NON-PLANAR ROADS
Authors:

Sergiu Nedevschi, Ciprian Pocol, Tiberiu Marita, Florin Oniga, Radu Danescu, Dan Frentiu, Rolf Schmidt and Thorsten Graf
Abstract: This paper presents a high accuracy stereovision system for obstacle detection and vehicle environment perception in various driving scenarios. The system detects obstacles of all types, even at high distance, outputting them as a list of cuboids having a position in 3D coordinates, size, speed and orientation. For increasing the robustness of the obstacle detection the non-planar road model is considered. The stereovision approach was considered to solve the road-obstacle separation problem. The vertical profile of the road is obtained by fitting a first order clothoid curve on the stereo detected 3D road surface points. The obtained vertical profile is used for a better road-obstacle separation process. By consequence the grouping of the 3D points above the road in relevant objects is enhanced, and the accuracy of their positioning in the driving environment is increased.
Download
Paper Nr: 349
Title:

STRUCTURED LIGHT BASED STEREO VISION FOR COORDINATION OF MULTIPLE ROBOTS
Authors:

Gui Yun Tian and Duke Gledhill
Abstract: This paper reports a method of coordinating multiple robots for 3D-object handling using structured light based stereo vision. The system structure of using two robots (puma and staubli) for playing chess has been proposed. The key techniques for surface reconstruction and rejection of ‘spike’ are discussed. The feature of the active vision system for 3D object acquisition and their application for robotics and automation are introduced. Following experimental studies, conclusion and further work have been derived.
Download
Paper Nr: 353
Title:

MORPHOLOGICAL CHOICE OF PLANAR MECHANISMS IN ROBOTICS
Authors:

Peter Mitrouchev
Abstract: In this paper a morphological confined choice for kinematic mechanisms in robotics is presented. It is based on symmetries of structures. Pairs of groups of mutually symmetrical mechanisms are detected. Thus, the number of possible configurations is confined by eliminating the symmetrical ones. Different cases of symmetries have been studied. Expressions for the calculation of the number of frames and end-effectors are presented. It enables the reduction of the number of structures by avoiding those that are isomorphic. Following this, examples for applications for various kinematic structures are presented, enabling the field of research to be restricted to the possible solutions.
Download
Paper Nr: 354
Title:

A FUZZY INTEGRATED APPROACH TO IMPEDANCE CONTROL OF ROBOT MANIPULATORS
Authors:

Silvério Marques, José Sá Da Costa, Luis Baptista and L.F. Baptista
Abstract: This paper presents an integrated fuzzy approach to recover the performance in impedance control, reducing the errors in position and force, considering uncertainties in the parameters of the manipulator model and contact surface model. This integrated strategy considers a fuzzy adaptive compensator in the outer control loop that adjusts the manipulator tip position to compensate for uncertainties present in the environment. In the inner loop, a fuzzy sliding mode-based impedance controller compensates for uncertainties in the manipulator model, based on an inverse dynamics control law. The system error, defines the sliding surfaces of the fuzzy sliding controller as the difference between the desired and the actual impedances. In order to evaluate the force/position tracking performance and to validate the proposed control structure, simulations results are presented with a three-degree-of freedom (3-DOF) PUMA robot.
Download
Paper Nr: 357
Title:

A REAL TIME GESTURE RECOGNITION SYSTEM FOR MOBILE ROBOTS
Authors:

Vanderlei Bonato, Adriano K. Sanches, M.M. Fernandes, João P. Cardoso, E. V. Simoes and Eduardo Marques
Abstract: This paper presents a vision system to be embedded in a mobile robot, both of them implemented using reconfigurable computing technology. The vision system captures gestures by means of a digital color camera, and then performs some pre-processing steps in order to use the image as input to a RAM-based neural network. The set of recognized gestures can be dened using the system on-chip training capabilities. All the above functionality has been implemented in a single FPGA chip. Experimental results have shown the system to be robust, with enough performance to meet real-time constraints (30 fps), and also high efficiency in the recognition process (true recognition rate of 99.57%).
Download
Paper Nr: 360
Title:

ROBUST SENSOR BASED NAVIGATION FOR AUTONOMOUS MOBILE ROBOT
Authors:

Immanuel Ashokaraj, Antonios Tsourdos, Peter Silson and Brian White
Abstract: This paper describes a new approach for mobile robot navigation using an interval analysis based adaptive mechanism for an Unscented Kalman filter. The robot is equipped with inertial sensors, encoders and ultrasonic sensors. The map used for this study is two-dimensional and it is assumed to be known a-priori. Multiple sensor fusion for robot localisation and navigation has attracted a lot of interest in recent years. An Unscented Kalman Filter (UKF) is used here to estimate the robots position using the inertial sensors and encoders. Since the UKF estimates are affected by bias, drift etc, we propose an adaptive mechanism using interval analysis with ultrasonic sensors to correct these defects in estimates. Interval analysis has been already successfully used in the past for robot localisation using time of flight sensors. But this IA algorithm has been extended to incorporate the sensor range limitation as in many real world sensors such as ultrasonic sensors. One of the problems of the use of interval analysis sensor based navigation and localisation is that it can be applicable only in the presence of land marks. This problem is overcome here using additional sensors such as encoders and inertial sensors, which gives an estimate of the robot position using an Unscented Kalman filter in the absence of land marks. In the presence of land marks the complementary robot position information from the Interval analysis algorithm using ultrasonic sensors is used to estimate and bound the errors in the UKF robot position estimate.
Download
Paper Nr: 361
Title:

LINEAR MODELLING AND IDENTIFICATION OF A MOBILE ROBOT WITH DIFFERENTIAL DRIVE
Authors:

Adelardo Medeiros, Antônio Araújo, Pablo Alsina and Patrícia Guerra
Abstract: This paper presents a modelling and identication method for a wheeled mobile robot, including the actuator dynamics. Instead of the classic modelling approach, where the robot position coordinates (x; y) are utilized as state variables (resulting in a non linear model), the proposed discrete model is based on the travelled distance increment ∆ᶩ. Thus, the resulting model is linear and time invariant and it can be identied through classical methods such as Recursive Least Mean Squares. This approach has a problem: ∆ᶩ can not directly measured. In this paper, this problem is solved using an estimate ~∆Ɩ based on a second order curve approximation. Experimental data were colected and the proposed method was used to identify the model of a real robot.
Download
Paper Nr: 362
Title:

MULTILEVEL DARWINIST BRAIN IN ROBOTS - Initial Implementation

Authors:

Francisco Bellas and Richard J. Duro
Abstract: In this paper we present a Cognitive Mechanism called MDB (Multilevel Darwinist Brain) based on Darwinist theories and its initial application to autonomous learning by robotic systems. The mechanism has been designed to permit an agent to adapt to its environment and motivations in an autonomous way. The general structure of the MDB is particularized into a two level architecture: reasoning and interaction. This structure corresponds to a generic cognitive model where world, internal and satisfaction models are used to select strategies that fulfil the motivation of the agent. The main idea behind the proposal is that all of the components of the mechanism are obtained and modified through interaction with the environment in real time by means of on line Darwinist processes, allowing for a natural learning curve. The mechanism is able to provide solutions based on experience or original solutions to new situations. The knowledge used by the agent is acquired automatically and not imposed by the designer. Here we discuss the basic operation of the mechanism and demonstrate it through a real example in which a hexapod robot is taught to walk efficiently and to reach an objective in its surroundings.
Download
Paper Nr: 364
Title:

ACTIVE SENSING STRATEGIES FOR ROBOTIC PLATFORMS, WITH AN APPLICATION IN VISION-BASED GRIPPING
Authors:

Benjamin Deutsch, Benjamin Deutsch, Frank Deinzer, Matthias Zobel and Joachim Denzler
Abstract: We present a vision-based robotic system which uses a combination of several active sensing strategies to grip a free-standing small target object with an initially unknown position and orientation. The object position is determined and maintained with a probabilistic visual tracking system. The cameras on the robot contain a motorized zoom lens, allowing the focal lengths of the cameras to be adjusted during the approach. Our system uses an entropy-based approach to find the optimal zoom levels for reducing the uncertainty in the position estimation in real-time. The object can only be gripped efficiently from a few distinct directions, requiring the robot to first determine the pose of the object in a classification step, and then decide on the correct angle of approach in a grip planning step. The optimal angle is trained and selected using reinforcement learning, requiring no user-supplied knowledge about the object. The system is evaluated by comparing the experimental results to ground-truth information.
Download
Paper Nr: 374
Title:

A MOBILE ROBOT MAPPING SYSTEM WITH AN INFORMATION-BASED EXPLORATION STRATEGY
Authors:

Francesco Amigoni, Vincenzo Caglioti and Umberto Galtarossa
Abstract: The availability of efficient mapping systems to produce accurate representations of initially unknown environments is undoubtedly one of the main requirements for autonomous mobile robots. This paper presents a mapping system that has been implemented on a mobile robot equipped with a laser range scanner. The system builds geometrical maps of the environment employing an exploration strategy that takes into account both the distance travelled and the information gathered to determining the observation positions. This strategy is based on stronger mathematical foundations than the exploration strategies proposed in literature: this is the distinctive feature of our approach and constitutes the main original contribution of this paper.
Download
Paper Nr: 377
Title:

ABOUT NATURE OF EMERGENT BEHAVIOR IN MICRO-SYSTEMS
Authors:

Sergey Kornienko and Olga Kornienko
Abstract: Micro-robotic systems have very limited computational and communicating resources on board. However they have a broad spectrum of tasks to be solved. One of approaches to solve these tasks by such capability restricted systems consists in utilizing emergent properties of many interacting robots. In the presented work we consider the questions what is the emergent behavior in technical systems and how this articial emergence differs from the natural analogue ? These points are discussed on examples of spatial and functional emergence in a group of ”micro-agents”.
Download
Paper Nr: 382
Title:

AUTOMATIC VISION-BASED MONITORING OF THE SPACECRAFT DOCKING APPROACH WITH THE INTERNATIONAL SPACE STATION
Authors:

Sergey Sokolov, Victor Sazonov, Andrey Boguslavsky, Khamzat Saigiraev and Alexander Smirnov
Abstract: The software package which allows to automate the visual monitoring of the spacecraft docking approach with the international space station is being considered. The initial data for this complex is the video signal received from the TV-camera, mounted on the spacecraft board. The offered algorithms of this video signal processing in real time allow to restore the basic characteristics of the spacecraft motion with respect to the international space station. The results of the experiments with the described software and real video data about the docking approach of the spacecraft Progress with the International Space Station are being presented. The accuracy of the estimation of the motion characteristics and perspectives of the use of the package are being discussed.
Download
Paper Nr: 385
Title:

DEAD RECKONING FOR MOBILE ROBOTS USING TWO OPTICAL MICE
Authors:

Marcello Restelli, Matteo Matteucci and Andrea Bonarini
Abstract: In this paper, we present a dead reckoning procedure to support reliable odometry on mobile robot. It is based on a pair of optical mice rigidly connected to the robot body. The main advantages are that: 1) the measurement given by the mice is not subject to slipping, since they are independent from the traction wheels, nor to crawling, since they measure displacements in any direction, 2) this localization system is independent from the kinematics of the robot, 3) it is a low-cost solution. We present the mathematical model of the sensor, its implementation, and some empirical evaluations.
Download
Paper Nr: 386
Title:

A INTERPOLATION-BASED APPROACH TO MOTION GENERATION FOR HUMANOID ROBOTS
Authors:

Koshiro Noritake, Shohei Kato and Hidenori Itoh
Abstract: This paper proposes a static posture based motion generation system for humanoid robots. The system generates a sequence of motion from given several postures, and the motion is smooth and stable in the balance. We have produced all the motions of Tai Chi Chuan by the system. Motion generation for humanoids has been studied mainly based on the dynamics. Dynamic based method has, however, some defects: e.g., numerous parameters which can not be always prepared, expensive computational cost and no guarantee that the motions are stable in balance. We have, thus, studied less dependent-on-dynamics approach. A motion is described as a sequence of postures. Our system figure out if we need extra postures to insert for stability. This method enables humanoid robot, HOAP-1 to do Tai Chi Chuan.
Download
Paper Nr: 390
Title:

REALISTIC DYNAMIC SIMULATION OF AN INDUSTRIAL ROBOT WITH JOINT FRICTION
Authors:

Ronald Aarts, Rob Waiboer and Ben Jonker
Abstract: This paper presents a realistic dynamic simulation of the closed-loop tip motion of a rigid-link manipulator with joint friction. The results from two simulation techniques are compared with experimental results. A six-axis industrial Stäubli robot is modelled. The LuGre friction model is used to account both for the sliding and pre-sliding regime. The manipulation task implies transferring a laser spot along a straight line with a trapezoidal velocity profile. Firstly, a non-linear finite element method is used to formulate the dynamic equations of the manipulator mechanism. In a closed-loop simulation the driving torques are generated by the control system. The computed trajectory tracking errors agree well with the experimental results. Unfortunately, the simulation is very time-consuming due to the small time step of the discrete-time controller. Secondly, a perturbation method has been applied. In this method the perturbed motion of the manipulator is modelled as a first-order perturbation of the nominal manipulator motion. Friction torques at the actuator joints are introduced at the stage of perturbed dynamics. A substantial reduction of the computer time is achieved without loss of accuracy.
Download
Paper Nr: 399
Title:

DYNAMIC TOOLS TO CONTROL COMPLEX SYSTEMS
Authors:

Mabed Mahfoud
Abstract: The idea of complex sequencing is strongly related to scheduling and real time systems. It appears when a resource has to be shared by more than one user or when a job must be handled by some concurrent entities. The originality of our research is mainly to build a dynamic link between a scheduling solution and a simulation approach based on Petri Nets (PN). This paper addresses with the modeling of an electroplating line with max plus algebra theory and Petri Nets. As a schedule representing a sequence that contains a series of jobs, we can obtain a corresponding polynomial by using Lagrange interpolation. Then, we can use these polynomials to ensure a real time connection between a schedule procedure and a Petri nets simulation. The use of this approach will lead us to deal with different disturbances. Indeed, for any disturbance we should calculate a new schedule and a new polynomial will be found. This polynomial will be assigned to Petri nets Model without modifying its structure.
Download
Paper Nr: 406
Title:

A SKELETON BASED METHOD FOR EFFICIENT 3D OBJECT LOCALIZATION - Application to teleoperation
Authors:

Djamel Merad, Narjes Khezami, Malik Mallem and Samir Otmane
Abstract: Our aim is to develop a vision system for teleoperation to localize an object. This system has to be used through Internet connection. The recognition problem addressed in this paper is to localize a 3D free-form object from a single 2D view of 3D scene. Using a skeletonization process allows to obtain two graphs, the first one representing an object in the scene (2D skeleton) and the second one representing a database object (3D homotopic skeleton). The method encodes geometric and topological information in the form of a skeletal graph and uses graph isomorphism techniques to match the skeletons and find the one-toone correspondences of nodes in order to estimate the object’s pose. Knowing skeleton is a set of lines centred within the 3D/2D objects, our method transforms the problem of free form object localization into points and lines pose estimation. Some experimental results on real images demonstrate the robustness of the proposed method with regard to occlusion, cluster and shadows.
Download
Paper Nr: 429
Title:

A NEW PARADIGM FOR SHIP HULL INSPECTION USING A HOLONOMIC HOVER-CAPABLE AUV
Authors:

Franz Hover, Samuel Desset, James Morash, Victor Polidoro, Chrys Chryssostomidis, Jerome Vaganay, Scott Willcox and Robert Damus
Abstract: The MIT Sea Grant AUV Lab, in association with Bluefin Robotics Corporation, has undertaken the task of designing a new autonomous underwater vehicle, a holonomic hover-capable robot capable of performing missions where an inspection capability similar to that of a remotely operated vehicle is the primary goal. One of the primary issues in this mode of operating AUVs is how the robot perceives its environment and thus navigates. The predominant methods for navigating in close proximity to large iron structures, which precludes accurate compass measurements, require the AUV to receive position information updates from an outside source, typically an acoustic LBL or USBL system. The new paradigm we present in this paper divorces the navigation routine from any absolute reference frame; motions are referenced directly to the hull. We argue that this technique offers some substantial benefits over the conventional approaches, and will present the current status of our project.
Download
Paper Nr: 441
Title:

ELECTROMYOGRAPHY BASED FINGER MOVEMENT IDENTIFICATION FOR HUMAN COMPUTER INTERFACE
Authors:

Dinesh Kumar and Pah Nemuel D.
Abstract: This paper reports experiments conducted to classify single channel Surface Electromyogram recorded from the forearm with the flexion and extension of the different fingers. Controlled experiments were conducted where single channel SEMF was recorded from the flexor digitorum superficialis muscle for various finger positions from the volunteers. A modified wavelet network called Thresholding Wavelet Networks that has been developed by the authors (D Kumar, 2003) has been applied for this classification. The purpose of this research was towards developing a reliable man machine interface that could have applications for rehabilitation, robotics and industry. The network is promising with accuracy better than 85%.
Download
Paper Nr: 443
Title:

VISUAL HAND MOVEMENTS FOR MACHINE CONTROL
Authors:

Dinesh Kumar, Sanjay Kumar and Arun Sharma
Abstract: A new technique for automated classification of human hand gestures for robotics and computer control applications is presented. It uses view-based approach for representation, and statistical technique for classification. This approach uses a cumulative image-difference technique where the time between the sequences of images is implicitly captured in the representation of action. This results in the construction of Temporal History Templates (THTs). These THT’s are used to compute the 7 Hu image moments that are invariant to scale, rotation and translation. The recognition criterion is established using K-nearest neighbor (K-NN) mahalanobis distance. The preliminary experiments show that such a system can classify human hand gestures with a classification accuracy of 92%. Our research has been carried on in the robotics framework. The overall goal of our research is to test for accuracy of the recognition of hand gestures using this computationally inexpensive way of dimensionality-reduced representation of gestures for its suitability for robotics.
Download
Paper Nr: 445
Title:

DIMSART: A REAL TIME - DEVICE INDEPENDENT MODULAR SOFTWARE ARCHITECTURE FOR ROBOTIC AND TELEROBOTIC APPLICATIONS
Authors:

Jordi Artigas, Detlef Reintsema, Carsten Preusche and Gerhard Hirzinger
Abstract: In this paper a software architecture for robotic and telerobotic applications will be described. The software is device and platform independent, and is distributed control orientated. Thus, the package is suitable for any real time system conguration. The architecture allows designers to easily build complex control schemes for any hardware device, easily control and manage them, and communicate with other devices with a plugin/plug-out modular concept. The need to create a platform where control engineers/designers could freely implement their algorithms, without needing to worry about the device driver and programming related issues, further motivated this project. Implementing a new control algorithm with the software architecture described here, requires that the designer simply follow a template where the necessary code is reduced to only those functions having to do with the controller. We conducted several teleoperation schemes, one of which will be presented here as a conguration example.
Download
Short Papers
Paper Nr: 39
Title:

CONTROL THROUGH STATE CONVERGENCE OF TELEOPERATION SYSTEMS WITH VARYING TIME DELAY
Authors:

Jose M. Azorin, Oscar Reinoso, Jose M. Sabater and Rafael Aracil
Abstract: Teleoperation systems that use Internet as communication channel must deal with varying time delays. In these situations, the system can become unstable due to the irregular variations of the time delay. In this paper, a control method of teleoperation systems that we presented considering constant time delays is applied to control a teleoperation system with varying time delays. The control gains obtained with a constant time delay can be used to control the teleoperation system with varying time delays because of the control method robustness. Experimental results are presented to illustrate the validity of the method.
Download
Paper Nr: 46
Title:

A SHALLOW DRAFT VEHICLE FOR INTERDISCIPLINARY RESEARCH AND EDUCATION
Authors:

Carl Steidley, Ray Bachnak, Wien Lohatchit, Alex Sadovski and Cody Ross
Abstract: Water quality data collection in shallow water areas can be a challenging task. Obstacles encountered in such environments include difficulty in covering large territories and the presence of inaccessible areas due to a variety of reasons such as a soft bottom or contamination. There is also a high probability of disturbing the test area while placing the sensors. This paper describes a NASA-funded project, which has had a great deal of student involvement and is currently in the test phase, to develop a remote-controlled, shallow-draft vehicle designed as a supplemental tool for our studies of the South Texas Coastal waters. The system transmits environmental data wirelessly via a radio to a docking and control station in real-time.
Download
Paper Nr: 59
Title:

MOTION PLANNING APPROACH OF A MULTI-FINGERED ROBOT FOR CARTON FOLDING OPERATIONS
Authors:

Hidetsugu Terada and Takayuki Kobayashi
Abstract: The motion planning approach of a multi-fingered robot for carton flap folding operations has been newly developed. This approach considers the loci of the tool center point for carton flap folding operations. Also that considers the pushing or fixing points of the carton flap. This approach is calculated from the rotating angle for carton flap folding and the position of a robot finger tip in contact with the carton surface, using inverse kinematics. And this approach can be adapted to changes of a carton size or a folding position. In cases in which the carton flap is folded using this approach, the robot finger tip touches the carton surface without slipping and moves along circular continuous path. Therefore in case of the rectangular carton box folding, each robot finger moves in each 2.5-dimensional Cartesian frame. In this report, the proposed approach is verified using a prototype robot system. This prototype system consists of two pairs of the robot fingers and rotating mechanism for carton paper. Each finger has a 3-DOF SCARA type robot and a 1-DOF linear motion system. The testing carton boxes can be folded to the desired shape.
Download
Paper Nr: 60
Title:

ANALYSIS OF THE ARCHITECTURE AND RELIABILITY OF DATA TRANSMISSION NETWORK USED FOR RADIO BASED CAB SIGNALING SYSTEM
Authors:

Wang Junfeng, Zhang Yong, Wang Huashen and Wang Xishi
Abstract: The application background and basic structure of train control system based on the combination of Radio Based Cab Signaling (RBCS) and Automatic Train Protection (ATP) is introduced. The architecture of the data transmission network used for RBCS is analyzed in detail, together with the reliability of radio data transmission.
Download
Paper Nr: 65
Title:

TWO APPROACHES FOR A SERVOMECHANISM CONTROL SYSTEM USING COMPUTER VISION
Authors:

João S. Tavares, Ricardo Ferreira and Francisco Freitas
Abstract: In this paper a servomechanism vision control system, based on hand language, is presented. The control images are acquired by a generic webcam and processed, in the working phase, in quasi real time. For this processing, two approaches were considered: in the first one, we used the object control moments to identify the desired order; in the second approach, we used image control orientation histograms. In both approaches, the preset orders images to be considered are acquired in the learning phase. The used servomechanism and the two approaches used for the vision control system are described and some advantages and weakness of each one are indicated. An example of an images control order set, which works satisfactory, is also presented and some conclusions and future work are also addressed.
Download
Paper Nr: 100
Title:

ON THE DECENTRALIZED CONTROL OF LARGE DYNAMICAL COMPLEX SYSTEM
Authors:

Madjid Kidouche, M. Zelmat and A. Charef
Abstract: This paper describes a systematic procedure to build reduced order analytical models for a design of decentralized controllers for large scale interconnected dynamical systems. The design method employs Davison techniques to affect decoupling of the interconnections into its subsystems components which is done by using the most dominant eigenvalues and the most influent inputs in each subsystem. In this way, advantage can be taken of the special structural feature of a given system to devise feasible and efficient decentralized strategies for solving large control problem which are impractical to solve by one shot centralized methods.
Download
Paper Nr: 107
Title:

PREDICTED POLAR MAPPING FOR MOVING OBSTACLE DETECTION
Authors:

Young-joong Kim, Beom-soo Kim and Myo-taeg Lim
Abstract: This paper presents the predicted polar mapping that is to improve the efficiency of an unexpected moving obstacle detecting system in a single vision-based robot. The polar mapping is used to simplify the segmentation of moving objects from the background and is performed with the focus of expansion (FOE) as the center. When the movement of the robot per a step becomes a bit large, then static objects or background are detected as moving objects. Thus, the velocity of the robot becomes so slow. Therefore, to enlarge the movement of the robot and to improve this system, we propose the predicted polar mapping that predicts the polar mapped image after robot moves to be admissible. In order to verify experimentally our proposed procedure, we make several comparative tests in the corridor.
Download
Paper Nr: 117
Title:

MOTION PLANNING FOR MOBILE ROBOTS IN DYNAMIC ENVIRONMENTS
Authors:

Jing Ren, Kenneth A. McIsaac and Xishi Huang
Abstract: In this paper, we present a motion planning technique for a multi-robot team in a complex dynamic environment. We define a cell-based navigation control law that can guide the robot team through the environment while avoiding collisions with both static and dynamic obstacles and other team members. To illustrate our techniques, we consider a robot team motion planning problem in a complex “maze” with obstacles of arbitrary shape. First, we assign potential values to a set of landmarks based on their shortest distance to the goal, and then we use a spline function to generate a potential field for the entire workspace, which is inherently free of undesired local minima. Simulation results show that robots can successfully transport materials along an optimal and collision-free path and reach the goal in a complex and dynamic maze environment. Finally we prove the derived control law is stable in all times.
Download
Paper Nr: 119
Title:

LASER-BASED ADAPTIVE CRUISE CONTROL FOR INTELLIGENT VEHICLES
Authors:

Miguel Á. Sotelo Vázquez, David Fernández Llorca, Eugenio Naranjo, Carlos González, Ricardo García, Teresa de Pedro and Jesús Reviejo
Abstract: Vehicle and highway automation is believed to reduce the risk of accident, improve safety, increase capacity, reduce fuel consumption and enchance overall comfort and performance for drivers. One of the most important research topics in the field of Intelligent Transportation Systems (ITS) is Adaptive Cruise Control (ACC), aiming at adapting the vehicle speed to a predefined value while keeping a safe gap with regard to potential obstacles. For this purpose, a laserscanner system provides the distance between the ego vehicle and the preceding vehicle on the road. The complete system can be understood as a Laser-based ACC controller, based on Fuzzy Logic, which assists the vehicle velocity control offering driving strategies and actuation over the throttle of a car. This controller is embedded in an automatic driving system installed in two testbed mass-produced cars operating in a real environment. The results obtained in these experiments show a good performance of the Laser-based gap controller, which is adaptable to all speeds and safe gap selections.
Download
Paper Nr: 138
Title:

INTEGRATING A POTENTIAL FIELD BASED PILOT INTO A MULTIAGENT NAVIGATION ARCHITECTURE FOR AUTONOMOUS ROBOTS
Authors:

Manikanth Mohan, Didac Busquets, Ramón López De Mántaras and Carles Sierra
Abstract: In this paper we present a new Pilot for a Multi-Agent based control architecture for Autonomous Robots. This Pilot is based on the use of virtual potential fields and is easy to implement yet effective. The Pilot functions as an autonomous agent in a complex Multi-Agent Architecture for the control of an autonomous robot. In this architecture, various agents are responsible for different tasks, and they might have to compete and cooperate for the successful completion of a particular navigation mission. The interaction between different agents is achieved through the use of a bidding mechanism. In this respect, we also present a way to define the bid for the new pilot, so that the pilot can be integrated easily into the Multi-Agent Architecture. The pilot has been tested on navigation experiments involving a real robot and it has given successful and encouraging results. We also deal with some problems of this pilot and ways to get around them.
Download
Paper Nr: 139
Title:

VERTICAL INTEGRATION OF TTP/A FIELDBUS SYSTEMS USING WEB SERVICES
Authors:

Volker Turau, Marcus Venzke, Christoph Weyer and Yesenia Vigil
Abstract: This paper presents a generic technique to expose data and control of fieldbus systems to applications located at the level of operational management. To provide a high degree of interoperability between the operational level and different fieldbus systems we utilize standardized techniques such as XML, HTTP, and Web services which can be deployed independently of the platform. The proposed service is based on the interface file system for TTP/A smart transducers. The defined interface provides high level abstractions appropriate for the integration into business applications and considers the latency introduced by the internet protocols.
Download
Paper Nr: 249
Title:

FUZZY CONTROLLER DESIGN FOR A THREE JOINT ROBOT LEG IN PROTRACTION PHASE - An optimal behavior inspired fuzzy controller design
Authors:

Mustafa S. Erden and Kemal Leblebicio
Abstract: A fuzzy controller design is performed for a three joint robot leg in protraction phase. The aim is to develop a controller to carry the tip point to any given destination. The design is based on the inspirations derived from optimal behaviors of the leg. The optimal trajectories are obtained by using optimization methods utilizing “numerical gradient” and “optimal control” successively. Separate fuzzy controllers are designed for each actuator. In writing the rules each actuator is considered to be an independent agent of the leg system. The protraction motion is divided into two epochs. For each epoch different controller systems are designed to switch from one to the other in between.
Download
Paper Nr: 262
Title:

PLATFORM-BASED TELEOPERATION CONTROL OF SYMBIOTIC HUMAN-ROBOT SYSTEM
Authors:

Tao Zhang, Vuthichai Ampornaramveth, Md. Hasanuzzaman, Pattara Kiatisevi and Haruki Ueno
Abstract: This paper presents a platform-based teleoperation control approach of symbiotic human-robot system. With frame-based knowledge representation, features of robots, human-robot interface and cooperative operation of symbiotic human-robot system are defined in the Software Platform of Agents and Knowledge Management (SPAK). By means of this software platform, human can communicate with robots using human-robot interface. Cooperative operation of multiple robots can be implemented by teleoperation control through wireless network. In this paper, platform-based teleoperation control of an actual symbiotic human-robot system comprised of human, humanoid robot (Robovie) and entertainment robot (AIBO) is implemented and the experimental results demonstrate its effectiveness.
Download
Paper Nr: 263
Title:

A LATERAL DIRECTOR AUTOPILOT DESIGN FOR CONFLICT RESOLUTION ALGORITHMS
Authors:

Mustafa S. Erden and Kemal Leblebicio
Abstract: Conflict resolution, namely avoidance of aircraft crushes, is one of the main problems to be solved in a free flight based air traffic system. The researches on conflict resolution are mainly performed in simulative environments. In the work presented here, a simple lateral director autopilot is designed for conflict resolution studies. Using such a simple autopilot, real aircraft dynamics can be incorporated to conflict resolution techniques and the simulation results can be made closer to real situations.
Download
Paper Nr: 273
Title:

VISUAL SERVOING TECHNIQUES FOR CONTINUOUS NAVIGATION OF A MOBILE ROBOT
Authors:

Nicolas Garcia Aracil, Oscar Reinoso, J. M. Azorín, E. Malis and R. Aracil
Abstract: A new method to control the navigation of a mobile robot which is based on visual servoing techniques is presented. The new contribution of this paper could be divided in two aspects: the first one is the solution of the problem which takes place in the control law when features appear or disappear from the image plane during the navigation; and the second one is the way of providing to the control system the reference path that must be followed by the mobile robot. The visual servoing techniques used to carry out the navigation are the image-based and the intrinsic-free approaches. Both are independent of calibration errors which is very useful since it is so difficult to get a good calibration in this kind of systems. Also, the second technique allows us to control the camera in spite of the variation of its intrinsic parameters. So, it is possible to modify the zoom of the camera, for instance to get more details, and drive the camera to its reference position at the same time. An exhaustive number of experiments using virtual reality worlds to simulate a typical indoor environment have been carried out.
Download
Paper Nr: 277
Title:

MAN AND WOMAN DISTINCTION USING THERMOGRAPHY
Authors:

Satoshi Nishino, Igarashi Sachiyo and Atsushi Matsuda
Abstract: Man and woman distinction is necessary to strengthen security and when various statistics on the visitor are taken in commercial facilities and so on. The conventional method of distinguishing a man from a woman is currently determined by using the person's appearance, the person's dress and in such cases, the way a person walks, the foot pressure, the hair type. But, these characteristics can be intentionally changed by human intervention or design. The proposed method gets the difference in the man's and woman's characteristics by taking images of the heat distribution of the person's face by Thermography. This is a man and woman distinction based on a new concept and idea which this is used for. Consequently, this can be used to distinguish a man from a woman even if a man turns himself into the woman intentionally (and vice versa), because this method involves biometrics authentication.
Download
Paper Nr: 280
Title:

A DSP-BASED ACTIVE CONTOUR MODEL
Authors:

Juan Zapata and Ramón Ruiz
Abstract: In this paper a DSP-based active contour model for tracking of the endocardium in a sequence of echocardiographic images is presented. If a contour is available in the first frame of a sequence, the contours in the subsequent frames are segmented. Deformable active contours is a technique that combine geometry, physics and approximation theory in order to solve problems of fundamental importance to medical image analysis; such as segmentation, representation and matching of shapes, and the tracking of objects in movement. The procedure has been developed on a DSP processor using its hardware features. The results are illustrated using a sequence of four-chambers apical echocardiographic images.
Download
Paper Nr: 282
Title:

LOCATING AND CROSSING DOORS AND NARROW PASSAGES FOR A MOBILE ROBOT
Authors:

Zhiyu Xiang, Vitor Santos and Jilin Liu
Abstract: In structured indoor environment, the structural information gathered from sensors can be divided into three different levels whose features increase gradually: walls, corners and passages. Besides detecting walls and corners, the paper focuses on narrow passage detecting and crossing. The sensor employed in the robot is a laser range finder. By detecting the Complete Points in the laser map, two types of narrow passages are easy to find. Two immediate applications of the proposed approach emerge: localization for robots and automatic crossing of passages. The validity of the method is proved with experimental results.
Download
Paper Nr: 289
Title:

HEXAPOD STRUCTURE EVALUATION AS WEB SERVICE
Authors:

Leonardo Jelenkovic, Domagoj Jakobovic and Leo Budin
Abstract: This paper describes several methods for evaluation of kinematic parameters of a Stewart platform. One of those methods is the calculation of workspace area both in numerical and graphical form. The second method allows us to analyze and estimate inherent mechanism errors that occur due to actuator errors, elastic and thermal deformations and other error sources. Furthermore, another procedure is presented which calculates certain kinematic parameters throughout the workspace area of the model and outputs them as numerical and graphical data. Finally, a forward kinematics algorithm designed for use in real-time conditions and its adaptation is presented. The described algorithms are implemented and made available as web services on the project web site (http://hexapod.zemris.fer.hr/).
Download
Paper Nr: 323
Title:

SIMULTANEOUS LOCALIZATION AND MAPPING BASED ON MULTI-RATE FUSION OF LASER AND ENCODERS MEASUREMENTS
Authors:

Leopoldo Armesto and Josep Tornero
Abstract: The SLAM problem in static environments with EKF is adapted for multi-rate sensor fusion of encoders and laser rangers. In addition, the formulation is general and can be adapted for any multi-rate sensor fusion application. The proposed algorithm, based on well-known techniques for feature extraction, data association and map building, is validated with some experimental results. This algorithm should been seen as a part of a complete autonomous robot navigation algorithm, also described in the paper.
Download
Paper Nr: 337
Title:

STEREO VISION SENSOR FOR 3D MEASUREMENTS - A complete solution to produce, calibrate and verify the accuracy of the measurements results
Authors:

Liviu Toma, Fangwu Shu, Werner Neddermeyer and Alimpie Ignea
Abstract: The goal of this paper is to build a stereo sensor to be used as a 3D measurement tool with direct application in automotive industry. The distance between the object to be measured and the stereo sensor is between 200 mm and 300 mm. This paper presents the solutions developed in order to produce, calibrate and verify a stereo sensor used to measure 3D coordinates with an accuracy of 0.1 mm. The measurement area is defined by a square with a side of 100 mm. The contribution of this paper to the extant literature is twofold. First, it presents a new method to compute the coefficient of the radial distortion. Second, it develops an image-processing algorithm, in order to minimize the errors that occur from the non-correspondence problem. The most important issues that need to be addressed are the following: defining a camera model in order to best simulate a real camera, and identifying the same point with both cameras of the stereo sensor (correspondence problem), in order to reduce the measurement errors.
Download
Paper Nr: 339
Title:

INTERACTIVE SOFTWARE FOR SYMBOLIC MODELING OF PHYSICAL SYSTEMS USING GRAPHS
Authors:

André Maitelli and Gilbert D. Azevedo Silva
Abstract: This paper presents a computational environment for teaching of control systems: Modsym. The software implements a graphical interface for physical systems modeling using graphs and calculates systems transfer functions in symbolic form. ModSym generalizes elements and dynamics variables of some physical systems based on the energy concept. This approach allows to represent and to connect elements of different systems in a linear graph. An algorithm implemented in the software, also presented in this paper, obtain a signal flow graph for the system linear graph which makes possible to use the Mason’s rule in calculating of the system transfer function.
Download
Paper Nr: 343
Title:

AUTOMATIC ANALYSIS AND VERIFICATION OF MSC-SPECIFIED TELECOMMUNICATION SYSTEM
Authors:

Lyudmila Matvyeyeva, Sergiy Kryvyy and Mariya Lopatina
Abstract: Last 20 years formal methods are being used widely to specify formally, analyze, verify and test software and hardware systems, particularly, telecommunication protocols. The paper presents automated verification system based on Petri nets formal modelling technique and linear algebra methods for automatic proving structural and some dynamic properties. Application of the system is considered on the telecom example.
Download
Paper Nr: 345
Title:

PET-TYPE ROBOT COMMUNICATION SYSTEM FOR MENTAL CARE OF SINGLE-RESIDENT ELDERIES
Authors:

Toshiyuki Maeda, Kazumi Yoshida, Hisao Niwa and Kazuhiro Kayashima
Abstract: This paper presents a pet-type robot communication system for mental care of single-resident elderies. The robot can communicate with the people autonomously, and also it is Internet-accessible and so that allows the people to communicate with others, directly or using the communication server. The system consists of pet-type robots and the information center. The pet-type robot can treat not only as an information terminal, but as a pet, which can talk to user(s), give information of the local communities, watch over them and send some information to carers at the information center if needed. Considering necessity and sufficiency, the robot has four motors; one for both ears, one for both eyes, one for the nose, and one for the neck. Motions generated by the motors symbolize emotions of the robot, which is essential for our object. We have demonstrated and examined some features of this robot system for elderies and got some good evaluation.
Download
Paper Nr: 356
Title:

TOWARDS IMPROVING ROBOTIC SOFTWARE REUSABILITY WITHOUT LOSING REAL-TIME CAPABILITIES
Authors:

Frederic Pont and Roland Siegwart
Abstract: We aim at improving sharability and reusability of software for autonomous mobile robots without sacrificing real-time capabilities. As a first step towards this goal, we focus on real-time Linux and we introduce the concept of a robotic hardware abstraction layer that provides for software reusability on different types of hardware and in real-time or non real-time context. We also present a preliminary implementation using RTAI Linux on the tour-guiding robot RoboX.
Download
Paper Nr: 368
Title:

SCAN MATCHING WITHOUT ODOMETRY INFORMATION
Authors:

Francesco Amigoni, Simone Gasparini and Maria Gini
Abstract: We present an algorithm for merging two partial maps obtained with a laser range scanner into a single map. The most unique original aspect of our algorithm is that it does not require any information on the position where the scans were collected but uses only geometrical features of the scans.
Download
Paper Nr: 376
Title:

FROM PETRI NETS TO EXECUTABLE SYSTEMS: AN ENVIRONMENT FOR CODE GENERATION AND ANALYSIS
Authors:

Joao Barros, Luis Gomes, Rui Pais and Rui Dias
Abstract: There is an increased awareness regarding the importance of executable system’s specifications, in particular, graphical specifications. Although most Petri nets variants are recognised as a versatile formalism, with an intuitive graphical specifications and a precise semantics, most Petri nets tools limit themselves to graphical editing and some type of simulation, system analysis, or both. This paper presents a new development environment based on Petri nets. This environment enables the use of ad-hoc Petri net classes as domain specific languages and allows the net models compositions and evolution through a set of orthogonal and generic modification operations. It also generates ANSI C code (easily extendable to other executable code) amenable to be implemented in general-purpose hardware platforms, without sophisticated resources available. Additionally, one major environment feature is the use of the same generated executable code, both for simulation and for analysis purposes.
Download
Paper Nr: 378
Title:

ON THE RECONSTRUCTION PERFORMANCE OF COMPRESSED ORTHOGONAL MOMENTS
Authors:

George Papakostas, Yiannis Boutalis, D.A. Karras and Vassilios Mertzios
Abstract: In this paper, a wavelet-based technique is applied to three moment feature vectors corresponding to three different families of orthogonal moments. The resulted compressed vectors are studied experimentally, in order to extract useful information about their behaviour to a reconstruction procedure. The reconstruction performance of these moments is identical to the amount of image information that they contain to certain moment orders. Since the moment vectors are imposed to compression at the high frequency components, a conclusion about their information redundancy can be also determined. The most efficient moment family, by means of the reconstruction error, will form feature vectors with low dimension, yet with high information content and thus will be very useful for pattern recognition applications, guarantying high recognition rates.
Download
Paper Nr: 384
Title:

A CONCEPT LEARNING BASED APPROACH TO MOTION CONTROL FOR HUMANOID ROBOTS
Authors:

Kiyotake Kuwayama, Shohei Kato and Hidenori Itoh
Abstract: This paper proposes a concept learning-based approach to motion control for humanoid robots. In this approach, the motion control system is implemented with decision tree learner for the acquisition of balancing property of itself body and movement and depth first search technique for the motion control based on the knowledge concerning balance and stability in the motion. Some performance results by humanoid robot HOAP-1 is reported: stable and anti-tumble motions to stand up from a chair. This paper also reports some performance for the change in the environments; stand up from a chair on slope and different in height.
Download
Paper Nr: 387
Title:

AUTOLOCALIZATION USING THE CONVOLUTION OF THE EXTENDED ROBOT
Authors:

Eduardo Espino, Vidal Moreno, Belen Curto and Aguilar Ramiro
Abstract: In order to construct autonomous robots which they move in a indoor environment, it is necessary to solve several problems such as the autolocalization. The problem of the autolocalization in a robot mobile consists of it must find its location within an apriori known map of its surroundings using the perceived distances by its sensors. The difficulties come from the fact that the signals of the sensors have noise, as well as the control signals and also the map could differ from the reality of the surroundings. The method which we presented joins the measures of the sensors and the signals of control in the called map of the extended robot; through of the convolution of this map and the a priori map of the environment, we can find the best matching between them, after a search into this calculated values, the location is obtained as a configuration that corresponds to the global maximum convolution. The method was implemented in an sonar-based robot, with kinematics differential. The results have validated widely our proposal.
Download
Paper Nr: 388
Title:

SUPERVISION AND TELECONTROL OF A RADIO BROADCASTING SYSTEM VIA INTERNET
Authors:

Joan Aranda and Eduard Sanz
Abstract: In this paper a recent application is showed that uses Internet as a supervision tool and remote control of a network of radio-TV relay stations to offer a better service to future clients. The relay stations network occupies a region of about 30.000 km2. The operator of this telecommunications network counts with a SCADA system which permits to the operator monitoring and control of the whole network. With the presented application users of the network can access to real time information about relevant aspects of the emission or change some parameters at anytime and from anywhere thanks to internet. The aspects of access security and safe communications have been taken care specially.
Download
Paper Nr: 398
Title:

CONSTRUCTION OF THE VORONOI DIAGRAM BY A TEAM OF COOPERATIVE ROBOTS
Authors:

Flavio S. Mendes, Júlio S. Aude, Paulo C. V. Pinto and Eliana P.l. Aude
Abstract: This paper presents a method for cooperation in the construction of Voronoi diagrams which is suitable for use in dangerous tasks performed by a team of robots. The algorithm has been implemented on a network of eight workstations using the MPI library. Two implementation approaches have been used. In the first one, no communication among the robots is required but some degree of redundancy in the work performed by the robots may result. In the second approach, a more cooperative scheme is adopted and, as a consequence, communication among the robots increases but the work performed by each one is reduced. In both approaches, the calculation time decreases almost linearly when adding robots to the team. Nevertheless, the second approach, more cooperative, has consistently produced better results. With the achieved speed-up, it is possible to use this algorithm in applications where the obstacle configuration within the robot team working area changes with time.
Download
Paper Nr: 400
Title:

SIMULATION, DESIGN AND PRACTICAL IMPLEMENTATION OF A MOBILE WIRELESS AUTONOMOUS SURVEILLANCE SYSTEM
Authors:

S. Janardhanan, P.S. Shingare and T.c. Manjunath
Abstract: The paper presents the design, implementation of the a unique type of computer controlled wireless mobile surveillance robot equipped with intelligence. Building an experimental autonomous mobile wireless vehicle, which has the ability to perform in real time environments is both a technical and scientific challenge and demands the development of systems for perception, modeling, planning and navigation. Within this scope, this paper describes the construction of a low cost mobile autonomous robot, intended for educational and surveillance purposes. This is a technology demonstration work. The objective of the work is to design, fabricate each part and construct a mobile robot and control it with a computer through wireless link which would accomplish two dimensional motion on a horizontal plane, moving from one place to another, avoiding obstacles in its path of motion by using infra-red sensors and performing the pick and place motion. The work was undertaken as a sponsored consultation based project under the guidance of the author in the institute.
Download
Paper Nr: 431
Title:

AUTONOMOUS NAVIGATION ROBOTIC SYSTEM TO RECOGNIZE IRREGULAR PATTERNS
Authors:

Danny D. Santos, Rafael Peñalver and Wilmer Pereira
Abstract: This paper presents an approximation of navigation problem under unknown environment using reinforcement learning. The motivation is to represent a robot that can move in a world with streets and intersections. Each intersection has a different quantity of streets (irregular blocks). The selected algorithms were Q-Learning and Value Iteration. The robot was programmed only with Q-Learning and we developed a simulation with both of them. This simulation allows making comparisons in order to determinate in which situation each algorithm is appropriate.
Download
Paper Nr: 433
Title:

ROBUST IMAGE SEGMENTATION BY TEXTURE SENSITIVE SNAKE UNDER LOW CONTRAST ENVIRONMENT
Authors:

Shu-fai Wong and Kwan-Yee K. Wong
Abstract: Robust image segmentation plays an important role in a wide range of daily applications, like visual surveillance system, computer-aided medical diagnosis, etc. Although commonly used image segmentation methods based on pixel intensity and texture can help finding the boundary of targets with sharp edges or distinguished textures, they may not be applied to images with poor quality and low contrast. Medical images, images captured from web cam and images taken under dim light are examples of images with low contrast and with heavy noise. To handle these types of images, we proposed a new segmentation method based on texture clustering and snake fitting. Experimental results show that targets in both artificial images and medical images, which are of low contrast and heavy noise, can be segmented from the background accurately. This segmentation method provides alternatives to the users so that they can keep using imaging device with low quality outputs while having good quality of image analysis result.
Download
Paper Nr: 442
Title:

EYE GAZE FOR COMPUTER CONTROL
Authors:

Poole E and Dinesh Kumar
Abstract: This paper reports the results of experiments that were conducted with five subjects to determine the reliability of the use of Electro-ocular gram (EOG) for controlling computers. Experiments included vertical and horizontal eye motion. Consideration was given to identify a relationship between the angle of the gaze and signal that could be applied to cover all test subjects and generate the required spatial control signals. The results obtained are encouraging. An assessment of the data has concluded that the EOG can be successfully utilised for spatial control applications. The study recommends the choice of bandwidth for the recording, inter and intra subject reliability and difference between the vertical and horizontal movement control.
Download
Paper Nr: 444
Title:

A VISUAL SERVOING ARCHITECTURE USING PREDICTIVE CONTROL FOR A PUMA560 ROBOT
Authors:

Paulo Ferreira and João Caldas
Abstract: A control system for a six degrees freedom Puma robot using a Visual Servoing architecture is presented. Two different predictive controllers, GPC and MPC, are used. A comparison between these two ones and the classical PI controller is performed. In this system the camera is placed on the robot’s end-effector and the goal is to control the robot pose to follow a target. A control law based on features extracted from camera images is used. Simulation results show that the strategy works well and that visual servoing predictive control is faster than a PI control.
Download
Paper Nr: 450
Title:

WIRELESS REMOTE MONITORING SYSTEM WITH FLEXIBLY CONFIGURABLE MULTIVISION
Authors:

Shinichi Masuda and Tetsuo Hattori
Abstract: Novel remote monitoring system for all day outdoor observation using wireless communication is proposed. It consists of three parts: a host station that is PC, remote station (camera and CPU) attached by solar cell and battery for power supply, and wireless sensor with ID (identification) signal. The remote station usually performs based on the event driven method by the sensor signal. It also can control the camera according to the sensor’s ID. So the multivision monitoring system is flexibly configurable. This paper describes the details of the system and evaluates the maximum number of connectable remote stations. Since the systems are now really running at many places in Japan, we consider that the fact shows its effectiveness in a practical sense.
Download
Paper Nr: 471
Title:

A METHOD FOR HANDWRITTEN CHARACTERS RECOGNITION BASED ON A VECTOR FIELD
Authors:

Tetsuya Izumi, Tetsuo Hattori, Hiroyuki Kitajima and Toshinori Yamasaki
Abstract: In order to obtain a low computational cost method for automatic handwritten characters recognition, this paper proposes a combined system of two rough classification methods based on features of a vector field: one is autocorrelation matrix method, and another is a low frequency Fourier expansion method. In each method, the representation is expressed as vectors, and the similarity is defined as a weighted sum of the squared values of the inner product between input pattern and the reference patterns that are normalized eigenvectors of KL ( Karhunen-Loeve) expansion. This paper also describes a way of deciding the weight coefficients based on linear regression, and shows the effectiveness of the proposed method by illustrating some experimentation results for 3036 categories of handwritten Japanese characters.
Download

Area 3 - Signal Processing, Systems Modeling and Control

Full Papers
Paper Nr: 11
Title:

THE LASER SIGNATURE IN CALIBRATION OF THE SERVOMECHANISM
Authors:

Edward Plinski, Jerzy Witkowski and Antoni Izworski
Abstract: The laser signature, which can be observed as a result of the CO<sub>2</sub> laser tuning, is used as a standard for calibration of the servomechanism. The servomechanism can be used for continuous investigations of the laser signatures of different laser media. Finally, some convenient signatures useful for a laser marker or single frequency laser operation can be find.
Download
Paper Nr: 16
Title:

AN APPLICATION OF THE INDEPENDENT COMPONENT ANALYSIS TO MONITOR ACOUSTIC EMISSION SIGNALS GENERATED BY TERMITE ACTIVITY IN WOOD
Authors:

Juan-Jose Gonzalez De La Rosa, Isidro Lloret Galiana, Juan M. Górriz Sáez and Carlos G. Puntonet
Abstract: In this paper an extended robust independent components analysis algorithm based on cumulants is applied to identify vibrational alarm signals generated by soldier termites in southern Spain (reticulitermes grassei), measured using low cost equipment. A seismic accelerometer is employed to strongly characterize these acoustic emissions. To support the proposed technique, vibrational signals from a low cost microphone have been mixed with known signals, and the mixtures processed by ICA. The experimental results confirm the validity of the proposed method, which has been taken as the basis for the development of a low cost, noninvasive, termite detection system.
Download
Paper Nr: 41
Title:

NEW DERIVATION OF THE FILTER AND FIXED-INTERVAL SMOOTHER WITH CORRELATED UNCERTAIN OBSERVATIONS
Authors:

Josefa Linares-Pérez, Raquel Caballero-Águila, Seiichi Nakamori and Aurora Hermoso-carazo
Abstract: A least-squares linear fixed-interval smoothing algorithm is derived to estimate signals from uncertain observations perturbed by additive white noise. It is assumed that the Bernoulli variables describing the uncertainty are only correlated at consecutive time instants. The marginal distribution of each of these variables, specified by the probability that the signal exists at each observation, as well as their correlation function, are known. The algorithm is obtained without requiring the state-space model generating the signal, but just the covariance functions of the signal and the additive noise in the observation equation.
Download
Paper Nr: 72
Title:

ESTIMATION ALGORITHM FROM RANDOMLY DELAYED OBSERVATIONS WITH WHITE PLUS COLOURED NOISES
Authors:

Josefa Linares-Pérez, S. Nakamori, Aurora Hermoso-carazo and M. I. Sánchez-Rodríguez
Abstract: A recursive algorithm for the least-squares linear one-stage prediction and filtering problems of discrete-time signals using randomly delayed measurements perturbed by additive white plus coloured noises are presented. It is assumed that the autocovariance function of the signal and the coloured noise are expressed in a semidegenerate kernel form and the delay is modelled by a sequence of independent Bernoulli random variables, which indicate if the measurements arrive in time or are delayed by one sampling time. The estimators are obtained by an innovation approach and do not use the state-space model of the signal, but only the covariance information about the signal and the observation noises and the delay probabilities.
Download
Paper Nr: 110
Title:

MAP-MATCHING OF RADAR IMAGES AND ELECTRONIC CHARTS USING THE HAUSDORFF DISTANCE
Authors:

Andres Guesalaga and Tzu-chiang Shen
Abstract: This paper describes a new method of image pattern recognition based on the Hausdorff Distance. The technique looks for similarities between a given pattern and its possible representations within an image. This method performs satisfactorily when confronted to image perturbations or partial occlusions. An extension of the classical Hausdorff Distance technique chooses the best candidate among multiple suboptimal solutions. The search strategy is based on the Branch and Bounds algorithm, where cells with low probability of containing the optimal solution are pruned, while feasible cells are divided again until the optimal solution is found. By using this strategy, exhaustive and no-informative searches are avoided among the possible combinations, reducing the processing time considerably. A case study is presented, where the proposed method is applied to calibration of surveillance radars using hydrographic charts as models for the radar echo images.
Download
Paper Nr: 170
Title:

DYNAMIC STRUCTURE CELLULAR AUTOMATA IN A FIRE SPREADING APPLICATION
Authors:

Alexandre Muzy, Antoine Aïello, David Hill, Jean-François Santucci, Eric Innocenti and Paul-Antoine Santoni
Abstract: Studying complex propagation phenomena is usually performed through cellular simulation models. Usually cellular models are specific cellular automata developed by non-computer specialists. We attempt to present here a mathematical specification of a new kind of CA. The latter allows to soundly specify cellular models using a discrete time base, avoiding basic CA limitations (infinite lattice, neighborhood and rules uniformity of the cells, closure of the system to external events, static structure, etc.). Object-oriented techniques and discrete event simulation are used to achieve this goal. The approach is validated through a fire spreading application.
Download
Paper Nr: 172
Title:

ON MODELING AND CONTROL OF DISCRETE TIMED EVENT GRAPHS WITH MULTIPLIERS USING (MIN, +) ALGEBRA
Authors:

Jean-Louis Boimond, Sébastien Lahaye, Jean-louis Boimond and Samir Hamaci
Abstract: Timed event graphs with multipliers, also called timed weighted marked graphs, constitute a subclass of Petri nets well adapted to model discrete event systems involving synchronization and saturation phenomena. Their dynamic behaviors can be modeled by using a particular algebra of operators. A just in time control method of these graphs based on Residuation theory is proposed.
Download
Paper Nr: 183
Title:

DESIGN OF LOW DELAY BANDPASS FIR FILTERS WITH MAXIMALLY FLAT CHARACTERISTICS IN THE PASSBAND AND THE TRANSMISSION ZEROS IN THE STOPBAND
Authors:

Naoyuki Aikawa and Yukio Mori
Abstract: The large group delay of the high order FIR filters is unacceptable in some applications. Therefore, recently, how to reduce the group delay of FIR filters has been studied intensively. To reduce the ringing in the time domain and to maximize the stopband attenuation, it is useful to design FIR filters with maximally flat characteristics in the passband and transmission zeros in the stopband. We present a mathematically closed form transfer function of low delay bandpass FIR filters with maximally flat amplitude in the passband and the transmission zeros in the stopband. Because of the mathematically closed form transfer function, the designing ters are very simple. Moreover, we propose a design method of low delay bandpass FIR filters with maximally flat amplitude in the passband and equiripple in the stopband by using an iterative method of a closed form transfer function and Remez algorithm.
Download
Paper Nr: 190
Title:

ADAPTIVE SMITH PREDICTIVE CONTROL OF NON-LINEAR SYSTEMS USING NEURO-FUZZY HAMMERSTEIN MODELS
Authors:

Jose Vieira and Alexandre Mota
Abstract: This paper proposes an Adaptive Smith Predictor Controller (ASPC) based on Neuro-Fuzzy Hammerstein Models (NFHM) with on-line non-linear model parameters identification. The NFHM approach uses a zeroorder Takagi-Sugeno fuzzy model to approximate the non-linear static function that is tuned off-line using gradient decent algorithm and to identify the linear dynamic function it is used the Recursive Least Square estimation with Covariance Matrix Reset (RLSCMR). This algorithm has the capability of follow fast and slow dynamic parameter changes. The proposed ASPC has special capabilities to control non-linear systems that have gain, time delay and dynamic changes through time. The implementation of the ASPC is made in two steps: first, off-line estimation of the non-linear static parameters that will be used to “get linear” the non-linearity of the system and second, on-line identification of the linear dynamic parameters updating direct and inverse models used in the ASPC. As an illustrative example, a gas water heater system is controlled with the ASPC. Finally, the control results are compared with the results obtained with the Smith Predictive Controller based in a Semi-Physical Model (SPMSPC).
Download
Paper Nr: 248
Title:

IMPLEMENTATION OF A DEVICE COMPATIBLE WITH DIFFERENT FIELDBUSES USING RECONFIGURABLE CIRCUITS
Authors:

Miguel Ángel Domínguez, M. DOLORES VALDÉS and M. JOSÉ MOURE
Abstract: Fieldbuses are serial communication networks very used in industrial control applications. They constitute the lower level of the communication networks in a flexible manufacturing system. Nowadays there are a lack of standardization in the area of fieldbuses and it supposes the existence of a lot of proprietary protocols. Thus, the interconnection of equipment from different manufacturers has become very problematic. It implies that a change in equipment supposes a change in the fieldbus too with the consequent economic losses. This paper proposes the implementation of a device using reconfigurable circuits such as FPGAs (Field Programmable Gate Arrays) that can be used as a communication processor, compatible with different fieldbuses making only little changes in the programming code and in the level and impedance matching circuit (depending on the electrical features of the corresponding fieldbus). Thus, the same hardware can be connected to different fieldbuses. The implementation of fieldbus communication processors using FPGAs implies that the interface can be easily adapted to different protocols (improvement in the interconnection between products of different manufacturers) and that the programming code can be easily modified, adding new functionality when it is necessary.
Download
Paper Nr: 255
Title:

IDENTIFYING AN OBSERVABLE PROCESS WITH ONE OF SEVERAL SIMULATION MODELS VIA UMPI TEST
Authors:

Nicholas Nechval, Konstantin Nechval, Edgars K. Vasermanis and Kristine Rozite
Abstract: In this paper, for identifying an observable process with one of several simulation models, a uniformly most powerful invariant (UMPI) test is developed from the generalized maximum likelihood ratio (GMLR). This test can be considered as a result of a new approach to solving the Behrens-Fisher problem when covariance matrices of multivariate normal populations (compared with respect to their means) are different and unknown. The test is based on invariant statistic whose distribution, under the null hypothesis, does not depend on the unknown (nuisance) parameters.
Download
Paper Nr: 270
Title:

INTEGRATED DESIGN OF STRUCTURE/CONTROLLER FOR PARALLEL INVERTED PENDULUM SYSTEMS
Authors:

Chiharu Ishii, Hiroshi Hashimoto and Shigehiko Yamamoto
Abstract: An integrated design of structure/controller for parallel inverted pendulum systems is presented. In practical parallel inverted pendulum systems, existence of a realizable stabilizing controller is inevitably determined depending on the position of center of gravity of two pendulums. In this paper these parameters are set as structural parameters in structural systems and a descriptor form representation is used to express the dynamics of parallel inverted pendulum systems. A state feedback gain and structural parameters are determined based on a design of linear quadratic regulator (LQR), in which a generalized Ricatti equation in LQR problem for the descriptor form representation is reduced to LMI conditions. Main contribution of this paper is to give a method to determine the position of center of gravity of two pendulums for parallel inverted pendulum systems in a sense of suitable for control. Based on the obtained structural parameters, some experimental works are executed. Experimental results show the effectiveness of the proposed design method.
Download
Paper Nr: 278
Title:

SOME FEASIBILITY ISSUES RELATED TO CONSTRAINED GENERALIZED PREDICTIVE CONTROL
Authors:

Sorin Olaru and Didier Dumur
Abstract: This paper analyzes the feasibility of the generalized predictive control law under constraints on the input, output or other auxiliary signals that depend linearly on the system variables. These constraints are formulated as sets of linear equalities or inequalities; the control sequence is therefore elaborated based on a quadratic optimization problem. The feasibility issues are related on one hand to the well posedness feature, and on the other hand to the compatibility with the set-point constraints. The prediction of the feasibility is of great interest from this point of view and necessary feasibility conditions are presented. Two possible approaches are followed, one strictly related to the specific set-point and the second, more general, examines the geo-metrical description of the optimization domain. The main practical advantage is that all the results are based on off-line numerical procedures offering qualitative information prior to the effective implementation.
Download
Paper Nr: 325
Title:

MODEL PREDICTIVE CONTROL FOR HYBRID SYSTEMS UNDER A STATE PARTITION BASED MLD APPROACH (SPMLD)
Authors:

Didier Dumur, Jean Thomas, Jean Buisson and Herve Guéguen
Abstract: This paper presents the State Partition based Mixed Logical Dynamical (SPMLD) formalism as a new modeling technique for a class of discrete-time hybrid systems, where the system is defined by different modes with continuous and logical control inputs and state variables, each model subject to linear constraints. The reformulation of the predictive strategy for hybrid systems under the SPMLD approach is then developed. This technique enables to considerably reduce the computation time (with respect to the classical MPC approaches for PWA and MLD models), as a positive feature for real time implementation. This strategy is applied in simulation to the control of a three tanks benchmark.
Download
Paper Nr: 335
Title:

AN ACCURATE AND EFFICIENT PARAMETER DECOUPLING FOR TRANSFER FUNCTION IDENTIFICATION

Authors:

In-yong Seo and Allan E. Pearson
Abstract: We present an improved parameter decoupling algorithm in estimating parameters that characterize the numerator and denominator of transfer function polynomials using the Adaptive Weighted Least Squares arising (AWLS) and Weighted Least Squares (WLS) from Fourier moment functionals of the Shinbrot type. This algorithm gives more accurate estimates and uses less computation than Pearson’s algorithm. Also, simulation examples show that this algorithm can be applied to the frequency analysis of lightly damped systems for which establishing steady state or stationary operation may require unreasonably long settling times.
Download
Paper Nr: 336
Title:

STRUCTURED INFORMATION PROCESSING FOR SELF-OPTIMIZING MECHATRONIC SYSTEMS
Authors:

Thorsten Hestermeyer, Holger Giese, Thorsten Hestermeyer and Oliver Oberschelp
Abstract: Self-optimizing mechatronic systems are based on intrinsic controller systems whose complexity by far exceeds that of currently available systems. In addition to procedures taken from artificial intelligence, procedures for a reconfiguration by means of appropriate design methods have to be integrated to fully implement self-optimization features. Special importance falls to a networking of such complex controller systems for the support of collaborative and emergent self-optimization. One main challenge lies in the safety-critical nature of the systems that requires the resulting software along with the technical system to show a predictably correct behavior in spite of networking, reconfiguration, and integration of procedures from artificial intelligence. The paper presents a concept for structuring and designing reconfigurable controller systems.
Download
Paper Nr: 340
Title:

MULTIRATE OUTPUT FEEDBACK BASED DISCRETE-TIME SLIDING MODE CONTROL FOR A CLASS OF NONLINEAR SYSTEMS
Authors:

Bijnan Bandyopadhyay, Janardhanan Sivaramakrishnan and Prashant Sridharrao Shingare Shingare
Abstract: The property of certain nonlinear continuous-time systems to be exactly representable in discrete-time is known as finite discretizability. This paper presents a method for the discrete-time sliding mode control for nonlinear systems that are finitely discretizable.
Download
Paper Nr: 346
Title:

IMPROVING PERFORMANCE OF THE DECODER FOR TWO-DIMENSIONAL BARCODE SYMBOLOGY PDF417
Authors:

Hee I. Hahn and Jung Goo Jung
Abstract: In this paper we introduce a method to extract the bar-space patterns directly from the gray-level two-dimensional barcode images, which employs the location and the distance between extreme points of profiles scanned from the barcode image. This algorithm proves to be very robust from the high convolutional distortion environments such as defocussing and warping, even under badly illuminating condition. The proposed algorithm shows excellent performance and is implemented in real-time.
Download
Paper Nr: 347
Title:

INVARIANT FEATURES FOR CHARACTER RECOGNITION
Authors:

Ryszard S. Choras
Abstract: This paper presents feature extraction method for recognition of isolated characters. Feature extraction is most important factor in achieving high recognition performance. We presented moments invariants as features for pattern recognition. This article analyzes the image feature extraction task on the basis of moments invariants for image recognition problem.
Download
Paper Nr: 355
Title:

A PRO-ACTIVE RESOLVER MODEL TO COPE WITH PARAMETER VARIABILITY IN THE MANUFACTURING CHAIN
Authors:

Joao Figueiredo and José Sá Da Costa
Abstract: In this paper a linearized model for Pancake resolvers is developed with the aim of compensating deviations on manufacturing inputs through computed corrections on the production controllable variables, mainly winding parameters. This model follows a two-step strategy where at the first step an accurate model computes the resolver nominal conditions and at a second step a linearized model based on production controllable variables computes the corrections on these controllable variables in order to compensate small deviations on the nominal conditions due to processes variability in the manufacturing. This model had been simulated and experimentally tested in a Siemens resolver manufacturing plant. The tests done proved the efficiency of the developed model and its usefulness in stabilizing the product specifications in a dynamic environment with high variability of manufacturing processes.
Download
Paper Nr: 366
Title:

ACTIVE ACOUSTIC NOISE CONTROL IN DUCTS
Authors:

José Sá Da Costa and Filipe Morais
Abstract: In this paper existing classical and advanced techniques of active acoustic noise cancellation (ANC) in ducts are collected and compared. The laboratory plant used in experience showed a linear behaviour and so the advanced techniques were not used. Due to delay on the plant, the feedback classical techniques could not be applied. The best results were obtained with the modified filtered-reference LMS (MFX-LMS) and filtered-u techniques. A very important conclusion is that the quadratic normalisation is needed to maintain the algorithms always stable. In this paper 18dB of attenuation of white noise and 35 dB of attenuation of tonal noise were achieved. Thus, ANC can be applied in a real situation resulting in important noise attenuations.
Download
Paper Nr: 367
Title:

STABILIZING CONTROL FOR HIGHER ORDER SYSTEMS VIA REDUCED ORDER MODEL - A PASSIVITY BASED APPROACH
Authors:

Bijnan Bandyopadhyay, Prashant Sridharrao Shingare Shingare and H. K. Abhyankar
Abstract: In this paper a methodology for design of stabilizing control for high order system via reduced order model is presented. In the first part a method is proposed for the reduction of original higher order passive system to a lower order stable model, using this reduced order model, a strictly passive controller of order equal to that of reduced order model is designed. It is shown that this lower order controller designed from reduced order model when applied to original higher order system results in to close loop stability.
Download
Paper Nr: 370
Title:

HYBRID UML COMPONENTS FOR THE DESIGN OF COMPLEX SELF-OPTIMIZING MECHATRONIC SYSTEMS
Authors:

Sven Burmester, Oliver Oberschelp and Holger Giese
Abstract: Complex technical systems, such as mechatronic systems, can exploit the computational power available today to achieve an automatic improvement of the technical system performance at run-time by means of self-optimization. To realize this vision appropriate means for the design of such systems are required.To support self-optimization it is not enough just to permit to alter some free parameters of the controllers. Furthermore,support for the modular reconfiguration of the internal structures of the controllers is required. Thereby it makes sense to find a representation for reconfigurable systems which includes classical, non-reconfigurable block diagrams. We therefore propose hybrid components and a related hybrid Statechart extension for the Unified Modeling Language (UML); it is to support the design of self-optimizing mechatronic systems by allowing specification of the necessary flexible reconfiguration of the system as well as of its hybrid subsystems in a modular manner.
Download
Paper Nr: 372
Title:

MATLAB MODELS OF ACMS IN CONTROL SYSTEMS
Authors:

Fei Hao, Graeme Chester, Alex Yakovlev, Fei Xia, Fei Hao and Ian G. Clark
Abstract: Asynchronous communication mechanisms (ACMs) are potentially useful in systems with heterogeneous timing as data connectors between processes belonging to different timing domains. In distributed, concurrent and embedded digital systems, there is often a desire to have some temporal decoupling between different parts of a system. ACMs provide a means with which concurrent processes can communicate with one another and yet still avoid synchronization. This paper describes efforts to implement MATLAB-based models of existing ACM algorithms. These techniques will facilitate the inclusion of ACMs in such application fields as distributed control and signal processing systems.
Download
Paper Nr: 383
Title:

EFFICIENT SYSTEM IDENTIFICATION FOR MODEL PREDICTIVE CONTROL WITH THE ISIAC SOFTWARE
Authors:

Paolino Tona and Jean-Marc Bader
Abstract: ISIAC (as Industrial System Identification for Advanced Control) is a new software package geared to meet the requirements of system identification for model predictive control and the needs of practicing advanced process control (APC) engineers. It has been designed to naturally lead the user through the different steps of system identification, from experiment planning to ready-to-use models. Each phase can be performed with minimal user intervention and maximum speed, yet the user has every freedom to experiment with the many options available. The underlying estimation approaches, based on high-order ARX estimation followed by model reduction, and on subspace methods, have been selected for their capacity to treat the large dimensional problems commonly found in system identification for process control, and to produce fast and robust results. Models describing parts of a larger system can be combined into a composite model describing the whole system. This gives the user the flexibility to handle complex model predictive control configurations, such as schemes involving intermediate process variables.
Download
Paper Nr: 389
Title:

MOMENT-LINEAR STOCHASTIC SYSTEMS
Authors:

Sandip Roy, George Verghese and Bernard C. Lesieutre
Abstract: We introduce a class of quasi-linear models for stochastic dynamics, called moment-linear stochastic systems (MLSS). We formulate MLSS and analyze their dynamics, as well as discussing common stochastic models that can be represented as MLSS. Further studies, including development of optimal estimators and controllers, are summarized. We discuss the reformulation of a common stochastic hybrid system——the Markovian jumplinear system (MJLS)—as an MLSS, and show that the MLSS formulation can be used to develop some new analyses for MJLS. Finally, we briefly discuss the use of MLSS in modeling certain stochastic network dynamics. Our studies suggest that MLSS hold promise in providing a framework for modeling interesting stochastic dynamics in a tractable manner.
Download
Paper Nr: 391
Title:

CONTEXT IN ROBOTIC VISION: CONTROL FOR REAL-TIME ADAPTATION
Authors:

Paolo Lombardi, Bertrand Zavidovique, Paolo Lombardi and Virginio Cantoni
Abstract: Nowadays, the computer vision community conducts an effort to produce canny systems able to tackle unconstrained environments. However, the information contained in images is so massive that fast and reliable knowledge extraction is impossible without restricting the range of expected meaningful signals. Inserting a priori knowledge on the operative “context” and adding expectations on object appearances are recognized today as a feasible solution to the problem. This paper attempts to define “context” in robotic vision by introducing a summarizing formalization of previous contributions by multiple authors. Starting from this formalization, we analyze one possible solution to introduce context-dependency in vision: an opportunistic switching strategy that selects the best fitted scenario among a set of pre-compiled configurations. We provide a theoretical framework for “context switching” named Context Commutation, grounded on Bayesian theory. Finally, we describe a sample application of the above ideas to improve video surveillance systems based on background subtraction methods.
Download
Paper Nr: 401
Title:

A STOCHASTIC MODEL OF PASSENGER TRANSPORT
Authors:

Klara Janglajew and Olga Lavrenyk
Abstract: We develop a stochastic model in which a recursive formula is derived for computing the mean value of income from sales of bus tickets. The model takes into consideration basic variable costs and the flow of passengers is given by a Poisson process. The recursive formula for the mean income is in the form of a linear discrete system with a random inhomogeneous part.
Download
Paper Nr: 439
Title:

EXPLORING THE LINEAR RELATIONS IN THE ESTIMATION OF MATRICES B AND D IN SUBSPACE IDENTIFICATION METHODS
Authors:

Catarina M. Delgado and P. S. Santos
Abstract: In this paper we provide a different way to estimate matrices B and D, in subspace identication algorithms. The starting point was the method proposed by Van Overschee and De Moor (1996) — the only one applying subspace ideas to the estimation of those matrices. We have derived new (and simpler) expressions and we found that the method proposed by Van Overschee and De Moor (1996) can be rewritten as a weighted least squares problem, involving the future outputs and inputs.
Download
Paper Nr: 440
Title:

RECURSIVE MOESP TYPE SUBSPACE IDENTIFICATION ALGORITHM
Authors:

Catarina M. Delgado and P. S. Santos
Abstract: In this paper two recursive algorithms, based on MOESP type subspace identification, are presented in two versions. The main idea was to show that we can represent subspace identification methods as sequences of least squares problems and implement them through sequences of modified Householder algorithms. Therefore, it is possible to develop iterative algorithms with most of the advantages of this kind of methods, and still improve the numerical efficiency, in order to deal with real-time applications and minimize the computational burden.
Download
Paper Nr: 447
Title:

NEW METHOD FOR STRUCTURAL CHANGE DETECTION OF TIME SERIES AS AN OPTIMAL STOPPING PROBLEM
Authors:

Tetsuo Hattori, Ken Nishimatsu and Hiromichi Kawano
Abstract: In general, an appropriate prediction expression and/or model is constructed to fit a time series though, the model begins to unfit (or not to fit) the time series from some time point, especially in the field that relates to human activity and social phenomenon. In such case, it will be important not only to quickly detect the unfitting situation but also to rebuild the prediction model after the detection as soon as possible. In this paper, we formulate the structural change detection problem in time series as an optimal stopping problem, using the concept of DP (Dynamic Programming) with a cost function that is the sum of unfitting (or not fitting) loss and action cost to be taken after detection. And we propose a method for optimal solution and show the correctness by proving a theorem. Also we clarify the effectiveness by showing the numerical experimentation.
Download
Short Papers
Paper Nr: 71
Title:

POLYNOMIAL ESTIMATION OF SIGNALS FROM UNCERTAIN OBSERVATIONS USING COVARIANCE INFORMATION
Authors:

Seiichi Nakamori, Raquel Caballero-Águila, Aurora Hermoso-carazo and Josefa Linares-Pérez
Abstract: The least-squares νth-order polynomial filtering and fixed-point smoothing problems of uncertainly observed signals are considered. The proposed estimators do not require the knowledge of the state-space model generating the signal, but only the moments (up to the 2νth one) of the signal and the observation noise, as well as the probability that the signal exists in the observations.
Download
Paper Nr: 102
Title:

SIMULATION OF SYSTEMS WITH VARIOUS TIME DELAYS USING PADE'S APPROXIMATION
Authors:

Mujo Hebibovic, Bakir Lacevic and Jasmin Velagic
Abstract: In this paper, Pade's rational functions have been simulated for approximating several characteristic values of time delay regarding the plant time constant. Several representative plants were tested in order to show in which cases Pade’s function approximates time-delay block well. Only if the ratio of time delay versus time constant of the plant is rather great, or the plant contains emphasized numerator dynamics; approximation capabilities get poorer. The convergence rate of n-order Pade’s function has been also analyzed by using Taylor series and phase-frequency characteristics.
Download
Paper Nr: 102
Title:

SIMULATION OF SYSTEMS WITH VARIOUS TIME DELAYS USING PADE'S APPROXIMATION
Authors:

Mujo Hebibovic, Bakir Lacevic and Jasmin Velagic
Abstract: In this paper, Pade's rational functions have been simulated for approximating several characteristic values of time delay regarding the plant time constant. Several representative plants were tested in order to show in which cases Pade’s function approximates time-delay block well. Only if the ratio of time delay versus time constant of the plant is rather great, or the plant contains emphasized numerator dynamics; approximation capabilities get poorer. The convergence rate of n-order Pade’s function has been also analyzed by using Taylor series and phase-frequency characteristics.
Download
Paper Nr: 103
Title:

A NEURAL NETWORK FRAMEWORK FOR IMPLEMENTING THE BAYESIAN LEARNING
Authors:

Luminita State, Catalina Cocianu, Viorica Stefanescu and Panayiotis Vlamos
Abstract: The research reported in the paper aims the development of a suitable neural architecture for implementing the Bayesian procedure for solving pattern recognition problems. The proposed neural system is based on an inhibitive competition installed among the hidden neurons of the computation layer. The local memories of the hidden neurons are computed adaptively according to an estimation model of the parameters of the Bayesian classifier. Also, the paper reports a series of qualitative attempts in analyzing the behavior of a new learning procedure of the parameters an HMM by modeling different types of stochastic dependencies on the space of states corresponding to the underlying finite automaton. The approach aims the development of some new methods in processing image and speech signals in solving pattern recognition problems. Basically, the attempts are stated in terms of weighting processes and deterministic/non deterministic Bayesian procedures. The aims were mainly to derive asymptotical conclusions concerning the performance of the proposed estimation techniques in approximating the ideal Bayesian procedure. The proposed methodology adopts the standard assumptions on the conditional independence properties of the involved stochastic processes.
Download
Paper Nr: 104
Title:

ON THE EFFICIENCY OF A CERTAIN CLASS OF NOISE REMOVAL ALGORITHMS IN SOLVING IMAGE PROCESSING TASKS
Authors:

Catalina Cocianu, Luminita State, Panayiotis Vlamos and Viorica Stefanescu
Abstract: The investigated noise removal algorithms are HRBA, HSBA, HBA, AMVR, PNRA, MMSE, MNR, MNR2 and NFPCA. The multiresolution support provides a suitable framework for noise filtering and for restoration purposes by noise suppression. The techniques used in the paper are mainly based on the statistically significant wavelet coefficients specifying the support. The performed tests reveal that the use of the multiresolution support proves powerful and offers a versatile way to handle noise of different classes of distributions.
Download
Paper Nr: 109
Title:

PARAMETRIC ESTIMATION OF SINUSOIDS IN NOISE - A comparison between parametric approaches and the definition of a regularized Smyth algorithm
Authors:

Aldo Balestrino, Andrea Caiti and Roberto Mati
Abstract: A comparison between well-established parametric algorithms and the more recent Smyth algorithm for estimation of sinusoidal signals in white noise is presented. The comparison is performed through a pseudo-Monte Carlo analysis on simulated data. The results obtained show that Smyth algorithm has a slightly better performance at large Signal-to Noise Ratios. However, when the SNR drops down, the performance of the Smyth algorithm dramatically decreases. A better performance with respect to both ESPRIT and Smyth algorithms at low SNR can be obtained by a regularized filtering procedure on the data.
Download
Paper Nr: 189
Title:

STATE OBSERVER FOR NONLINEAR SYSTEMS: APPLICATION TO GRINDING PROCESS CONTROL
Authors:

Seraphin C. Abou and Thien-My Dao
Abstract: Due to the measurement problems encountered in mineral processes, observers are appropriate ingredients of advanced model based control algorithm. The measurement problem can be solved by designing nonlinear observer. This paper discusses the way in which a state observer may be designed to control a special class of nonlinear systems. Focus is put on the pertinent applicability of the scope of these techniques, to control the dynamics of mills in mineral processes. The approach uses a small number of parameters to control the mill power draw affected by sudden changes within the system. It provides with principles and ability of the system to adapt to changing circumstances due to intermittent disturbances (like for instance changes in hardness of the raw material). Performance and stability analysis was developed. Using a generalised similarity transformation for the error dynamics, it is shown that under boundedness condition the proposed observer guarantees the global exponential convergence of the estimation error. This way, the nominal performance of the process is improved but the robust stability is not guaranteed to fully avoid the mill plugging.
Download
Paper Nr: 329
Title:

FROM DIOID ALGEBRA TO P-TIME EVENT GRAPHS
Authors:

Mohamed D. Alaoui and Philippe Declerck

Abstract: The (max,+) algebra is usually used to model Timed event graph. In this paper, we show that P-time event graphs which extend Timed event graph, can be modelled using maximum, minimum and addition operations. The result is a new model called interval descriptor system where the time evolution is not strictly deterministic but belongs to intervals. The cycle-time vector allows us to to check its correct behaviour and to verify the existence of a state trajectory. Particularly, it detects the presence of token-deads which can generate a deadlock.
Download
Paper Nr: 331
Title:

WATER SUPPLY REMOTE MONITORING SYSTEM: A CASE STUDY
Authors:

Henrique Proença, F. F. Reinaldo Ribeiro, José Carlos Metrôlho and Ricardo Oliveira
Abstract: In recent years, there has been enormous research interest in natural resources monitoring. So, there is a need to develop easily accessible, cheap and reliable information systems for monitoring and early warning, which could be used in most natural resources. This paper presents an ongoing information system development that aims at the monitoring and supervising of some parameters on water supply, such as quality and quantity. To implement our system we use several technologies in order to monitoring about 100 water tanks in an area of ±1000 Km2. Included in these technologies are GSM communication, web infrastructure and sensing equipment that allows the access of information from any part of the world. In paper sections the main blocks of the system architecture are described in detail.
Download