Passivity-Based Active Disturbance Rejection Control of an Omnidirectional Mobile Robot

This paper studies a passivity-based active disturbance rejection control scheme for trajectory tracking control of an omnidirectional mobile robot (OMR). The proposed control design effectively exploits the natural structure of robot dynamics. First, the passivity property of the OMR is analyzed based on the dynamic model. Then the controller is designed, consisting of two parts. One part is used to compensate the disturbances estimated by a modified reduced-order extended state observer, which avoids the inverse operation of the inertia matrix in control design. The other part is passivity-based trajectory tracking controller, which is designed based on the energy shaping plus damping approach. In addition, stability analysis of the proposed control system is presented. Finally, simulation results show the effectiveness of the proposed control design in improving tracking performances, compared with traditional active disturbance rejection control.