Stability Analysis of a Wheel-Track-Leg Hybrid Mobile Robot

This paper proposes a new wheel-track-leg hybrid robot. The hybrid robot comprises a robot body, four driving mechanisms, four independent track devices, two supporting legs and one wheel lifting mechanism, which can fully benefit different advantages from wheeled, tracked and legged robots to adapt itself to varied landforms (the rough terrain and high obstacle). Based on the symmetrical mechanical structure, locomotion modes of the mobile robot are analyzed. With the coordinate transformation matrix, the center of mass of the robot is described. Moreover, the stability pyramid method is used to analyze on the climbing motion, especially in the hybrid locomotion mode. Through theoretical analysis, simulation and experimental verification, it’s proven that the robot can remain stable in the process of climbing motion.