Development of Body Rotation Mechanism for Wheeled Robot to Enhance Trafficability and Overcome Mobility Limitation

A wheeled robot operating on various complex terrains with scattered obstacles and steep slopes must be capable of surmounting obstructions and coping with the extreme driving environment. This paper proposes a body rotation mechanism that controls the load distribution on the robot wheel for the robot to surmount rocky obstacles and steadily ascend deformable slopes. This work formulates a robot dynamics model based on the wheel-complex terrain interaction model to analyze the mechanical effect of the proposed body rotation mechanism. Moreover, an optimal body rotation configuration integrating the robot dynamics model and non-dominated sorting genetic algorithm-II is obtained to choose the appropriate body rotation control strategy. The numerical analysis results conclusively prove the effectiveness of the proposed mechanism. The robot with its fabricated platform is field tested by allowing it to surmount a rocky obstacle and ascend a deformable slope. The results indicate that the proposed body rotation mechanism is an effective approach for enhancing the mobility of a wheeled robot in traversing complex terrains.