A composite controller for uncertain omnidirectional mobile robots

Issues of tracking control of an omnidirectional mobile robot with parametric uncertainty, including the electrical ones, are presented. The input matrix, under such circumstances, depends on the unknown system parameters and therefore the so-called control singularity might occur in the corresponding adaptive controller. A composite control design is proposed to circumvent such a difficulty. It consists of three main parts: an adaptive linearizing controller for compensating the linear-in-parameter nonlinearities; a supervisory agent which hands over temporarily the control authority to the third part of a robust controller during the singularity. Simulation is carried out to demonstrate the validity of the proposed design in the final.