Coordinated Motion Control for a Wheel-Leg Robot with Speed Consensus Strategy

In this article, a speed consensus strategy that combined distributed active disturbance rejection control (ADRC) framework with a consensus algorithm is proposed for the coordinated motion control of a wheel-leg robot. In addition, combined with the proposed strategy, a new steering system is designed. The proposed strategy can deal with the coordinated motion control problem of the robot with internal modeling uncertainty and external disturbances. To this end, a new ADRC consensus protocol for the robot motion control system is proposed under an undirected graph. By applying this consensus protocol to the robot motion control system, the problem of coordinated motion control can be solved. The proposed new steering system consists of four inverted Stewart platforms that can achieve an angle range of - \text{60}^{\circ} - + \text{60}^\circ and make the steering precisely and nimbly. To deal with the consensus issue with different leaders when the robot is steering, the proposed ADRC consensus protocol is combined with the new steering system. The application of the proposed method is illustrated in the electric parallel wheel-leg robot system. Experimental results are provided to verify the effectiveness of the proposed approach.