Dynamic Biped Walking Control on Rugged Terrain Using the Linear Inverted Pendulum Mode

Abstract

An experimental study of a biped robot is presented. A new scheme named "Linear Inverted Pendulum Mode" is utilized for controlling biped walking on rugged terrain. We developed a 6 d. o. f. biped robot "Meltran II" which has light weight legs and walks in a two dimensional vertical plane . After discussing the control systems for the support leg and the swing leg, we applied these control laws to the real robot and obtained following results. 1. Support phase dynamics of the biped robot under the proposed control law can be well represented by a linear model with a viscous term. 2. An adequate vertical speed at touchdown and a short duration of two leg support after touchdown help smooth support leg exchange with a small loss of momentum. Based on these results, a whole biped control system was implemented. In our experiment, biped walking with a half step period of 0.5-1.0s and a half stride of 10-14cm was realized on a flat floor. The maximum walking speed was 24cm/s. Our robot also walked over a box of 3.5cm height at a speed of 20cm/s.