Robust finite-time consensus formation control for multiple nonholonomic wheeled mobile robots via output feedback

The finite-time formation control for multiple nonholonomic wheeled mobile robots with a leader-following structure is studied. Different from the existing results, the considered mobile robot has the following features: (i) a higher-order dynamic model, (ii) the robot's velocities cannot be measured, and (iii) there are external disturbances. To solve the problem, a finite-time consensus formation control algorithm via output feedback is explicitly given. At the first step, some finite-time convergent observers are skillfully constructed to estimate both the unknown velocity information and the disturbance in finite time by imposing certain assumptions on the disturbances. Then, on the basis of the integral sliding-mode control method, a disturbance observer-based finite-time output feedback controller is developed. Rigorous proof shows that the finite-time formation can be achieved in finite time. An example is finally given to verify the efficiency of the proposed method.