Output-feedback near-optimal control of chained systems

In this paper, a new optimal trajectory tracking control is proposed for nonholonomic systems in chained form by using only output feedback information. After establishing a simple condition on the desired trajectory to ensure the uniform complete observability for the tracking error system, a globally and exponentially convergent observer is synthesized in closed form. Then, an output-feedback near-optimal control is obtained also in closed form for real-time implementation, and it is shown to be smooth, globally exponentially stabilizing, and near-optimal. Simulation results are provided to verify its effectiveness