TERRAIN ADAPTIVE MOTION AND FREE GAIT OF A 6-LEGGED WALKING MACHINE

A six-legged hydraulic walking machine, called MECANT I, is introduced . It has been developed for research purposes in outdoor environments. The paper describes the motion planning method used. It is based on a ''top-down'' approach where the vehicle body motion control is execut ed through the body motion planning which in turn is divided into two parts called profile tracking and terrain adaptation. The estimated su pport plane is used as a model of the local terrain. The kinematic con straints are included into the body path planning by applying a ''plan -and-check'' approach. A free gait planner based on a ''state machine' ' approach is introduced. The planner uses a rule-based method in dete rmination of the time instant for changing the present support pattern and in selection of the new supporting leg configuration.