Uncertain Nonholonomic Systems Control via Sampled-Data Output Feedback of Motor Robot With Two-Dimensional Z-States

Nonholonomic systems with uncertain nonlinearities are sufficiently important to research due to the numerous applications in the real world. It is imperative to find a sampled-data controller for nonholonomic systems due to their implementation within digital computers. It has been proven that under a lower-triangular growth condition, a class of nonholonomic system with a single z-state can be globally stabilized by a sampled-data output feedback controller whose observer and control laws are discrete-time and linear. In this paper, we will further extend the results to the two-dimensional z-states which is more challenging since the boundedness of the change of coordinates is not proved. To solve this problem, we firstly design a controller for the z-system, which can guarantee the boundedness of the change of coordinates after a certain time. From this, we can construct a globally stabilizing output feedback controller for nonholonomic systems. The examples and computer simulations were conducted to show the effectiveness of the proposed controllers for the two-dimensional z-states.