Movement-mode-switching mechanism for a hybrid wheel/legged mobile robot

Abstract

This paper introduces a movement-mode-switching mechanism for a hybrid wheel/legged mobile robot. With the switching mechanism, two movement modes are achieved independently sharing the same actuator, thus fewer actuators are used in the robots. A clutch is designed to accomplish the movement-mode-switching process. The trapezoid tooth meshing as a tolerance design is used, which not only leads to better engagement, but also increases the transmission accuracy. The drawing back and recovery of the shape memory alloy conduces to the reciprocation of the clutch, which transfers motion towards wheels and legs from the bevel gears, respectively. Then, motion and force simulation of the switching process is made with Adams. The results are used to check the material of the clutch and ensure the feasibility of the switching mechanism. Finally, a practical application is introduced using the switching mechanism, showing an adaptive capacity of the system to most wheel/legged robots.