Comparison Analysis of A Transformable Wheel

Search and rescue missions require robots possess high speed and efficiency on both even and rough terrains. Hybrid robots that combine the advantages of different locomotion mechanisms are developed to solve this problem. Yet the design of previous research is usually complicated because they have separate wheels, tracks and legs. In this paper, a novel wheel-track-leg hybrid robot that has simple morphology is presented. By utilizing a transformable rim, the robot wheels can switch to tracks or legs according to different grounds. We cut the wheel rim into several segments and joint the ends, which makes the rim foldable. Mode-switch is achieved by the folding or unfolding of the transformable rim, so that no separate wheel, track, or leg is needed. We conduct a geometry configuration analysis and propose two optional design of the transformable wheel. By comparison the supposed better one is chosen and an initial prototype is fabricated to verify the transformation of the rim and basic function of the robot.