Design and Control of a Foldable and Reconfigurable Multi-Terrain Vehicle With Variable Wheelbase

Abstract

High mobility/speed and adaptability to complex environment are two important performance indexes for mobile robots. Legged robots are with high environmental adaptability, while wheeled robots are with high mobility. Since existing mobile robots cannot meet these two requirements simultaneously, a flexible, extensible and reconfigurable multi-terrain vehicle with a varying wheelbase is proposed innovatively. The vehicle body contains two main parts: one middle plate and two side plates, which both have two active wheels and are connected to the same shaft, which has two passive wheels on both sides. Specially, the included angle between one middle plate and two side plates are driven by an active motor, and then the vehicle can behave many forms by adjusting the wheelbase between two pair active wheels. Under the body configuration, the multi-terrain vehicle can achieve the motions of crossing deep pit, climbing stair, crossing height limiting rod, climbing crevice and crossing pipe by folding and varying the wheel base. Firstly, the detailed mechanical structure of multi-terrain vehicle is designed. Secondly, the kinematics of the multi-terrain vehicle including the inverse and forward solutions of wheelbase and centroid velocity, are analyzed. Thirdly, the control scheme combining travel speed controller, turn controller and wheelbase controller is proposed based on PID algorithm. Finally, many simulations and experiments both validate the feasibility and effectiveness of proposed structure and control of multi-terrain vehicle.

Cooperative control strategy of wheel-legged robot based on attitude balance

“…Mobile robots have become more commonplace in commercial and industrial settings. Wheeled and legged robot are two classical kinds of mobile robot, and they are used in different applications [1,2]. The wheeled robots can move very fast on flat grounds without too much body oscillation, but they cannot stride across some rough terrains.…”