Using soft computing techniques for improving foot trajectories in walkingmachines

Garcia, E Gonzalez-de-Santos, P

E. Garcia et P. Gonzalez-de-santos, Using soft computing techniques for improving foot trajectories in walkingmachines, J ROBOTIC S, 18(7), 2001, pp. 343-356

24

INGLESE

Article

AI Robotics and Automatic Control

JOURNAL OF ROBOTIC SYSTEMS

0741-2223 → ACNP

18

7

2001

343 - 356

ISI

0741-2223(200107)18:7<343:USCTFI>2.0.ZU;2-9

Walking machines have been investigated during the last 40 years and some b asic techniques of this field are already well known. However, some aspects still need to be optimized. For instance, speed seems to be one of the maj or shortcomings of legged robots; thus, improving leg speed has been chosen as the main aim of this work. Although some algorithms for optimizing traj ectory control of robot manipulators already exist, we propose a more compu tationally efficient method that employs fuzzy set theory to involve real d ynamic effects over leg motion instead of an inaccurate mathematical model. In this article, we improve leg speed by automatically tuning the accelera tion of legs. For this purpose, we define fuzzy rules based on experiments and we find the optimal acceleration for every given trajectory. A simple f uzzy inference system is used to compute the required acceleration. It is b ased on five rules using three linguistic variables. Final results show tha t foot acceleration tuning for straight trajectory generation is a suitable method for achieving accurate, smooth and fast foot movements. Also it is shown that under some conditions average leg speed can be increased up to 1 00% using the control methods herein proposed. (C) 2001 John Wiley & Sons, Inc.