Predefined-time robust contour tracking of robotic manipulators

Robotic tasks are primarily defined to comply to spatial and time constraints, and in several of such tasks, it is required to track a nominal contour depending just on spatial coordinates, without involving the time variable in the definition of such a contour, in contrast to conventional trajectory tracking schemes. With the aim to satisfy the salient requirements of these robotic tasks, this paper presents an integrated robust controller. The contour is encoded by using a robust velocity field, such that, any particle immerse in such field converges in predefined-time to a predefined vicinity of the given contour. Then, a robust controller is proposed to enforce the velocity field, in turns, in predefined-time. In this sense, a predefined-time-precision contour tracking is assured, by considering a robust controller that does not assume the exact knowledge of the robot parameters for its real-time implementation. Numerical simulations are conducted to highlight the reliability of the proposed scheme.