Biorobotics Laboratory BioRob

Semester Project, spring semester 2009: Locomotion exploiting body dynamics on the Cheetah robot

Abstract

This project aims at designing a simple model of the Cheetah robot under Webots simulation software. Cheetah is a small, light wight quadruped robot that faetures three segmented legs, thus very pronounced body dynamics. The model should make abstraction of the complex physics of the legs but should still produce a close to reality behavior. Furthermore, a pre-existing CPG capable of various gaits had to be implemented. The interest of this work lies in the exploration of various parameters that affect locomotion, like stance phase duration or the amplitude of oscillation for the hip servos. The goal is to determine the most efficient sets of parameters for each gait.

Cheetah Model

The model developped for the Cheetah robot. Note that the complex leg design was replaced with a rather simple Webots components. This was achieved by making all the calculations for the leg retraction at the controller level. This approach yields a greater modularity for the model : leg designs can be changed at will with no changes to the model.