A Reconfigurable Rocker-Bogie Robot for High Step Climbing and Turning
This work improves maneuverability for rocker-bogie robots used in rough terrain, offering a practical trade-off between turning efficiency and step-climbing capability.
A reconfigurable rocker-bogie robot achieves zero-radius turning at over 5x speed and 17% of the torque of conventional designs, while climbing a 40 cm step in 6.4 s.
This study proposes a reconfigurable rocker-bogie mechanism that achieves efficient turning motion with a small number of actuators while maintaining high step-climbing capability. By installing motors at the bogie joints and actively swinging up and down bogies, the system enables switching between four-wheel and six-wheel configurations. Omnidirectional wheels are mounted on the rear ends of the rockers, allowing smooth turning in the four-wheel configuration based on a differential-drive model. Experimental evaluation using a prototype robot demonstrated that the proposed mechanism achieves zero-radius turning at a speed more than five times that of a conventional rocker-bogie mechanism equipped with six non-steerable grip wheels, while requiring only approximately 17% of the total average wheel torque. In addition, the robot successfully climbed a 40 cm step with an average climbing time of 6.4 s, confirming its high turning and step-climbing performance.