Chen H.-YWang T.-HHo K.-CKo C.-YLin P.-CLin P.-C.PEI-CHUN LIN2022-03-222022-03-2220210094114Xhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-85105806008&doi=10.1016%2fj.mechmachtheory.2021.104348&partnerID=40&md5=c42e09b0ff019f5e43603db92a50ad93https://scholars.lib.ntu.edu.tw/handle/123456789/598971We report on the development of a novel two-degrees-of-freedom module capable of transforming its shape between a wheel and a leg, with the length of the latter approximately 3.4 times the wheel radius. The leg-wheel module was empirically built and experimentally evaluated. It utilizes a linkage mechanism and can perform a smooth yet rapid leg-wheel transition within 0.25 s. The design concept, selection of the linkage parameters, and kinematics are described in this paper. The rapid transition from a wheel to a leg endows the robot with wheel-to-leap behavior. The general motion planning strategy of the leg-wheel, as well as the wheel-to-leap behavior, are explained in the demonstration example. The results confirm that the module can perform wheel-to-leap behavior with a height of up to 4.6 times the wheel radius. ? 2021Leaping behaviorLeg-wheel moduleLeg-wheel transformationMechanism designTrajectory planningDegrees of freedom (mechanics)Machine designMotion planningRobot programmingConcept selectionDesign conceptFast transformationLinkage mechanismTrajectory PlanningTwo-degree-of-freedomWheelsjournal article10.1016/j.mechmachtheory.2021.1043482-s2.0-85105806008