Artículos

Task Based Mechatronic System Design using Differential Evolution Strategies

Diseño de Sistemas Mecatrónicos Basado en Tareas usando Estrategias de Evolución Diferencial

Carlos Alberto Cruz Villar*, Jaime Álvarez Gallegos** and Miguel Gabriel Villarreal Cervantes***

Cinvestav–IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360 México, D.F. E–mails: cacruz@cinvestav.mx*; jalvarez@cinvestav.mx**; gvillarr@cinvestav.mx***.

Article received on October 18, 2007
Accepted on August 12, 2008

Abstract

A dynamic design approach for a mechatronic system called task based mechatronic system design approach (TBMSDA) is stated as a nonlinear dynamic optimization problem (NLDOP) and it is solved by using a differential evolution technique. The design of a parallel robot is carried out by this approach which integrates in a simultaneous way both the structure design parameters of a parallel robot and the PID controller gains in order to improve the position errors and the robot dexterity for executing a specific task. The TBMSDA considers the dynamic system as an equality constraint into the optimization problem. Through the TBMSDA, an optimal combination of the structure and PID controller gains for a planar five–bar parallel robot is obtained. Simulation results show the effectiveness of this design approach.

Keywords: Mechatronic design, Task based design, Evolutionary algorithms, System optimization, Parallel robot.

Resumen

Se establece un enfoque de diseño dinámico para un sistema mecatrónico denominado enfoque de diseño de sistemas mecatrónicos basado en tareas. Se plantea como un problema de optimización dinámica no lineal y su solución se basa en el uso de técnicas de evolución diferencial. Con este enfoque, se realiza el diseño de un robot paralelo al integrar en forma simultánea los parámetros del diseño de la estructura mecánica del robot paralelo y los parámetros del diseño de las ganancias del controlador PID con el propósito de optimizar el desempeño en los errores de posición y en la destreza del robot al ejecutar una tarea específica. En el problema de optimización se considera la dinámica del sistema como una restricción de igualdad. Con este enfoque de diseño, se obtiene una combinación óptima de la estructura y de las ganancias del controlador PID para un robot paralelo de cinco eslabones planar y para su controlador. Resultados de simulación muestran la efectividad de este enfoque de diseño mecatrónico.

Palabras clave: Diseño mecatrónico, Diseño basado en la tarea, Algoritmos evolutivos, Optimización de sistemas, robot paralelo.

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Acknowledgments

This work is supported by the Phd. CONACYT scholarship 182799.

Appendix 1: Pseudo code of the differential evolution algorithm [Mezura, et. al., 2006]

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