On the Robustness and Reliability in the Pose Deformation System of Mobile Robots

A major vulnerability of mobile robots operating in more environments is their fragility in facing disturbances. A two-fold solution is proposed in this paper. First, a deformable structure was designed to reduce turbulence and to adapt to the uneven ground. Second, a novel control strategy is employed to avoid the limitations of the existing methods. In particular, among the existing solutions, the PID controller is known to be severely limited in handling disturbances and failures and the model-based designs all require detailed mathematical model, which may not be readily available, especially in the case of failures. To address these issues, a solution based on active disturbance rejection control is proposed in this paper, for its simplicity in design and tuning and its robustness against parameter variations and even failures in the pose deformation system. The proposed solution is systematically validated in the simulation, and the results are promising. The performance of the system was maintained in the presence of disturbances and uncertain dynamics, and the reliability of the robot is considerably improved when the unknown leg failures occurred.