Trot Gait for a Quadruped Walking Robot on Unknown Slope Using ZMP

Abstract

We focus on a quadruped robot as a mobile platform which would work at various environment such as disaster sites, offices and factories. In this paper, we assume that terrain consists of slopes and we propose a walking gait for a quadruped robot on unknown slopes. In this method, the robot basically walks in trot gait because trot gait has both high stability and practical walking speed in order to walk stably on steep slopes. At first, robot estimates slant of the slope by using body attitude and foot positions on the slope. Then it generates walking pattern for the robot to walk stably on the slope by using inverted pendulum model and multi-mass model of the robot. The proposed method was verified through experiments with a quadruped robot TITAN-VIII walked on slopes where a step or other slope exist halfway.