Modeling and stability control of steering and reconfiguration motion for wheel-legged metamorphic robot

This paper introduces a wheel-legged metamorphic robot, that combines elements from both wheeled vehicles and legged mechanisms. It can switch between driving on wheels and walking on legs. One major challenge is ensuring stability during steering and reconfiguration, as the robot can become unstable during this process. To address this, we designed the steering and reconfiguration motion based on the robot’s design and established a spatial kinematic model using the homogeneous coordinate transformation method. A virtual prototype was created for verification results. Additionally, an electromechanical dynamic model was developed for the robot’s center-of-mass position-adjusting mechanism. To enhance system stability during steering and reconfiguration, a fuzzy-PID algorithm based on zero-moment-point theory was designed to control the slider movement within this mechanism. The effectiveness of this stability control has been verified through simulation and experimental validation.