Design and Analysis of a Mobile Robot With Transformable Wheel-Legged Mechanism

Abstract In this paper, a mobile robot with transformable wheel-legged mechanism is proposed to effectively cope with unstructured terrain in the work environment, especially steps. By using the combination of ratchet-crank-pilot bar mechanism and elastic element, the reliability of the deformation process of the robot wheel is ensured, the number of actuators required is reduced, and the efficiency of the drive system is improved. The kinematic analysis of deformation mechanism of the robot is carried out, and the mechanical study of its deformation process is carried out. Based on the kinematic model of the robot, the important factors affecting the robot's success in climbing over the step are analyzed, and a method is proposed to evaluate the step-climbing performance of the robot's transformable wheel-legged mechanism. The structural dimensions of the transformable wheel-legged mechanism were optimized by using the multi-objective artificial Hummingbird Algorithm (MOAHA) to provide a better step-climbing performance. In addition, the key factors affecting the robot's step climbing performance were verified by a virtual prototype, and a physical prototype was also designed and tested in real environments, and the results verified the good performance of this robot in terms of terrain adaptability.