Output feedback nonlinear H∞ control of wheeled mobile robots formation

This paper presents a procedure to design robust controllers for a group of wheeled mobile robots (WMRs) in formation. Wheeled mobile robots exchange informations according to a pre-specified communication digraph. Stable motions are generated by a decentralized control law based on the robots coordinates. In addition, the nonlinear dynamic equations of the robots are described in state-space form where the parameters matrices depend on the angular velocities of the wheels. Output feedback controllers based on nonlinear H_infin approaches are designed in order to guarantee the stability formation. Results obtained from simulation illustrate the effectiveness of this procedure.