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Velocity Detection Application of HDNS2000 in Robot Soccer

J. Zhou, C.-L. Lin, G.-A. Wang and X. Zhou

Hohai Univ., Chang Zhou, China

Pages: 172-175

Abstract: The soccer Robot match is a competitive and complicated activity, in which the accuracy of the system strategy is heavily depended on the motion performance of Robot. To prevent the condition that the wheel of the Robot skids when starts up, this paper presents a new velocity detection method. By using of the HDNS-2000 to detect the actual motion state of the Robot which is used as the velocity feedback signal, the method can achieve the precision control of the Robot.


Optimization of Velocity Control of Soccer Robot

J. Zhou, W. Wu, K. Li and C. Lin

Hohai Univ., Chang Zhou, China

Pages: 176-178

Abstract: In the half-dependent robot soccer, quick startup for the robot is needed, the performance of startup can directly influence the accuracy of system strategy. This paper provides a new method of velocity control in case of sliding during the quick startup of carrier. Friction is applied to prevent or reduce the sliding between the wheel and ground. Meanwhile, this paper introduces the optimization of velocity control and corresponding program. Experimental result shows that it is an effective design.


Modelling and Robust PID-Control of a Shape Memory Alloy Actuated Haptic Finger

E. Kolyvas, Y. Koveos, G. Nikolakopoulos and A. Tzes

Univ. of Patras, Greece

Pages: 179-184

Abstract: The development of (SMA) actuated devices is hindered by the existence of an accurate and yet simplified model. The highly non–linear behavior that is exhibited by these materials does not allow a straightforward application of the classical control strategies met in the field. This current research effort proposes the linearization of a simplified model describing the “shape memory effect” of SMAs and the implementation of a PID controller, which is tuned with the aid of the Linear Quadratic Regulator theory, based on Linear Matrix Inequalities techniques. The proposed scheme is applied to a single–DOF robot manipulator that is activated by two SMA wires and the overall model is controlled via the utilization of the calculated LMI–tuned PID controller. Simulation results are presented that prove the efficacy of the proposed control scheme.


Robust Adaptive Neural Network Controller Based on Variable Structure System

N. Sadati, R. Ghadami and M. Bagherpour

Sharif Univ. of Technology, Tehran, Iran

Pages: 185-190

Abstract: In this paper, a Robust adaptive neural network controller (RANNC) based on variable structure system for robotic manipulators is proposed to alleviate the problems met in practical implementation using classical variable structure controllers. The chattering phenomenon is eliminated by substituting single-input single-output radialbasis- function neural networks (RBFNN's), which are nonlinear and continuous, in lieu of the discontinuous part of the control signals present in classical forms. The weights of the hidden layer of the RBFNN's are updated in an online manner to compensate the system uncertainties. The key feature of this scheme is that prior knowledge of the system uncertainties is not required to guarantee the stability. Moreover, a theoretical proof of the stability and convergence of the proposed scheme using Lyapunov method is presented. To demonstrate the effectiveness of the proposed approach, a practical situation in robot control is simulated.


IV. Automation, Instrument and Measurements

Minimising the Number of Tool Switches with Tools of Different Sizes 

C. Raduly-Baka1, T. Knuutila2 and O. Nevalainen2

1Elcoteq Design Center Oy, Salo, Finland,  2Univ. of Turku, Finland

Pages: 191-197

Abstract: In this paper we address the combined problem of job-ordering and tool placement, where each tool can occupy more than one slot of the primary storage magazine. The capacity of the magazine is limited so that all the tools neccessary in the production cannot fit into the magazine at the same time, and the cost of magazine reorganization depends linearly on the number of tool moves. Our task is to find the order of processing the jobs and the positions to put the tools in the magazine, so that the total cost of switching tools from one job to the next is minimized. We introduce a new heuristic for the problem. The algorithm hybridizes an efficient tool switching algorithm based on the matrix permutation problem and a novel two level storage management algorithm. We compare the proposed solution method to previous approaches from the literature. Our comparisons indicate that the new algorithm procudes results with costs almost a third of the costs produced by algorithms previosly known in this field.


Performance Improvement of the Induction Motor Drive by Using Robust Controller 

S. Selvaraj, V. Geetha and N. Devarajan

Government College of Technology, Coimbatore, India

Pages: 198-203

Abstract: The transient response of the induction motor is obtained by using its d-q reference model. The transient response is improved by using optimal control technique because of the property of best possible control. By solving Ricatti equation, a controller gain matrix is developed such that the performance index is minimum. This gain matrix will give feedback control law. The controller will give control signal according to this law. The output is fed back and the response is analyzed. Thus the transient response is improved. This controller is robust against disturbances.


Decentralized Load-Frequency Control of a Two-Area Power System via Linear Programming and Optimization Techniques

C. Parisses1, N. Asimopoulos1 and P. Fessas2

1Technol. Educ. Inst. of West Macedonia, Kozani, Greece,  2Aristotle Univ. of Thessaloniki, Greece

Pages: 204-209

Abstract: In this paper we consider the decentralized load-frequency control (LFC) of a two-area power system. The model of the power system is determined, and is viewed as an interconnected system (A, Bd), for which the methods of the decentralized control are applied; these are based on the intercontrollability matrix D(s), its kernel U(s), and the equivalent system {M(s), I2} in the operator domain. Based on this, a decentralized control via linear programming methods, and with decentralized optimization techniques is determined. Several responses are given and compared.


Periodic Disturbance Suppression in a Steel Plant with Unstable Internal Feedback and Delay

C. Furtmueller1, L. del Re1, H. Bramerdorfer2 and K. Moerwald2

1Johannes Kepler Univ., Linz, Austria,  2VOEST-ALPINE Industrieanlagenbau GmbH & Co.,  Austria

Pages: 210-215

Abstract: During continuous casting, especially of modern steel grades or at higher casting velocities, undesired oscillating disturbances may occur, which strongly impair the quality of the final product, or even lead to costly plant downtime. In this paper, both a novel model based explanation of these level oscillations in terms of unstable internal feedback and delay time, as well as a corresponding control to reject the oscillations are presented. The first part of the paper shows how these oscillations arise from couplings inside the strand and how they can be explained in terms of approximated periodic oscillations. To this end, both a new approach to model this oscillatory behavior as well as a frequency analysis is shown. This plant structure poses difficulties for control, as there is a substantial delay time in the plant and the disturbing oscillations depend on the quantitatively unknown internal feedback. To cope with these problems, a new control structure is proposed. Further a prediction based approach is presented, which allows to eliminate the periodic patterns in the oscillations and thus to lead those to rest.


Modeling and Control of Industrial Tunnel-Type Furnaces for Brick and Tile Production  

P. Michael and S. Manesis

Univ. of Patras, Greece

Pages: 216-221

Abstract: The dynamic behavior of an industrial tunneltype furnace is of the fundamental importance for the quality of the processed products. The knowledge of the furnace dynamics can make the control of the system easier as well as it can eliminate certain operational problems. The various subsystems existent in a tunnel-type furnace are usually controlled by conventional techniques and independent controllers offering simply an acceptable operation of the whole system. This paper approaches the overall furnace system by considering both mathematical modeling and fuzzy logic based techniques. It proposes a control scheme for model-based coordination of the individual subsystems which are controlled locally by fuzzy controllers combined with conventional ones. The proposed control structure can be easily applied to the process environment and the implementation may be realized directly on a programmable logic controller.


On the Derivation of the Monodromy Matrix of the Buck Converter 

D. Giaouris, B. Zahawi and V. Pickert 

Univ. of Newcastle upon Tyne, UK

Pages: 222-226

Abstract: The study of bifurcations phenomena in the dc-to-dc buck converter, which may not be common in smooth dynamic systems, is based on the derivation of an iterative map that approximates the operation of the converter. This paper presents a quantitative proof for the derivation of the total fundamental solution matrix before, during and after the system changes topologies as a result of the converter switching. The proof is based on upper semi-continuous Filippov inclusions applied on transversal intersections of the discontinuous hypersurface.


Improving the Pickups of Components on a Gantry-Type Placement Machine

S. Pyöttiälä, T. Knuutila and O. Nevalainen

Univ. of Turku, Finland

Pages: 227-231

Abstract: The advantages of using multi-head gantry machines in printed circuit board assembly are flexibility and efficiency combined with a relatively low acquisition price. However, the practical efficiency of this machine type depends on several difficult decisions that have to be made by a machine operator. In this paper two basic problems that have a significant effect on the use of a gantry machine are considered. The first problem deals with the pick-ups of the components using the nozzles in the placement arm and the second problem is about selecting suitable nozzles into the placement arm. The goal is to achieve a better understanding of the difficulty of these two problems and build up effective algorithms that can be used to solve problems in a restricted environment where the rest of the factors, such as the placement order of the components or the component to feeder slot assignment, are fixed.


Identifying the Problematic Units in the Chains of Supplies of Industrial Clusters 

M. Velev

Technical Univ. of Sofia, Bulgaria

Pages: 232-234

Abstract: The presence of problematic units in the supply chains disturbs the links in the clusters and seriously hampers their functioning. Their identification and timely rectification is of great importance for the development of well-grounded strategic plans for developing the clusters and enhancing their competitiveness. The aim of the present article is to put forward a suggestion for an approach of identifying and analyzing the missing and weak units in industrial clusters.


Evaluation of Industrial Networked Control Systems Using Hardware-In-The-Loop Simulation  

T. Mellios, C. Kansoulidou and G. Hassapis

Aristotle Univ. of Thessaloniki, Greece

Pages: 235-241

Abstract: The performance of advanced control algorithms implemented on networked control devices is highly dependent on the network delay. As most algorithms are not designed by taking this implementation parameter into consideration there is a need to evaluate the performance of these algorithms before commissioning them. In this work the hardware-inthe- loop simulation is proposed as a possible evaluation technique. The hardware-in-the-loop simulator is defined as the facility that consists of a computer-based simulation of the plant linked to the communication network and the actual control devices on which the algorithm will be implemented. In order to demonstrate the way of using such a facility for evaluating the performance of a control algorithm, an experimental hardware-in-the-loop simulator based on the Profibus-DP industrial network standard has been realized and the study of the LQC control of a cement milling circuit was undertaken.


An Adapted Partial Method for Schedule Preparation for the Start and Finish of the Mechanical Machining of Lots in Virtual Cellular Manufacturing System

I. Dakov and A. Petkova

Technical Univ., Sofia, Bulgaria

Pages: 242-245

Abstract: This paper presents a method for schedule preparation for the start (prolongation) and finish of lots machining which is adapted to the conditions of the Virtual Cellular Manufacturing Systems for mechanical machining. The aim of the schedule is to show which lots will be machined in the VCMS during the next plan periods and to specify the terms (times) for the start and finish of lot machining within each one of them. The schedules are to be formed consecutively – at the end of each plan period for a horizon from three to five plan periods. The plan period could be from one day until six days (a workweek). It depends on the prevalent prolongation of the machining of lots in the VCMS and the workweek duration. By means of the elaborated algorithm the sequence of the schedule development was specified.


Tactile Displays: a Short Overview and Recent Developments 

V. Chouvardas, A. Miliou and M. Hatalis

Aristotle Univ. of Thessaloniki, Greece

Pages: 246-251

Abstract: Tactation is the sensation perceived by the sense of touch. Tactation is based on the skin receptors. The skin nerves can be stimulated by mechanical, electrical or thermal stimuli. Apart from fibers for pain, skin has six more types of receptors. A review of the state of the art concerning the physiological and technological principles, considerations and characteristics, as well as latest implementations of micro-actuator based tactile graphic displays and the relative software interfaces structures and representations is presented. Fabrication technologies are reviewed in order to demonstrate the potential in tactile applications. Existing electronic Braille displays for accessibility are limited to text-based information. Graphic tactile displays enable for viewing images by the sense of touch on a reusable surface and substitution of the visual/auditory sense. Applications include education, engineering/artistic design, web surfing, and viewing of art and photographs. Tactile substitution can be used in augmenting accessibility for the blind or deaf in order to: (a) to enhance access to computer graphical user interfaces, (b) to enhance mobility in controlled environments. In general tactation based interfaces may allow communication of visual information to the brain in situations where the visual or hearing system is already overloaded such as race car drivers, airplane pilots, operating rooms, virtual reality and tele-presence.

 

 

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