Mechanical design of a compact and dexterous quadruped robot

Abstract

This manuscript introduced the modularized structural design of a medium sized quadruped robot with desired compact and dexterous mobility. In detail, the ball screw transmission and the four-bar linkages mechanism were adopted to construct the quadruped robot, and then the relationship between the torque of the knee joint and the torque of the motor was modelled and analyzed. Moreover, the mechanical performance of transmission is analyzed, then the practical result indicates that the shank should be configurated to get close as much as possible to the limited position of extension while walking. The loading analysis further showed that the structural strength of each leg is still enough, when adding 200N external force that similar to the whole weight of the robot to one foot. Based on the optimized design, the mechanical prototype was accomplished, and the corresponding control strategy were briefly illustrated. Finally, locomotory planning in typical walking and when the robot falls down were discussed preliminarily.