Motion control of leg-wheel robot for an unexplored outdoor environment

We have constructed a leg-wheel mobile robot called ChariotII that has mechanically separated wheels and legs which allows it to utilize the advantages of the two mechanisms. A new motion control approach, the leg-wheel passive hybrid crawl gait (LWPCG) motion control approach, for moving ChariotII is discussed under the environment of unexplored rough terrain in this paper. To enable the robot to negotiate a extensive range of unexplored terrain, an automatic control function which shifts the profile of the desired foot trajectory (automatic profile shift, or APS) has also been implemented. The proposed motion control approach is extremely simple computationally, does not require knowledge of the robot's dynamic model or environmental parameters, and does not necessitate late the use of external sensors. The effectiveness of this method is confirmed through simulations and experiments.