Output feedback stabilization by reduced order finite time observers using a trajectory based approach

We use finite time reduced order continuous-discrete observers to solve an output feedback stabilization problem for a class of nonlinear time-varying systems whose outputs contain uncertainty. Unlike earlier works, our feedback is discontinuous, but it does not contain distributed control terms. Our trajectory based approach is based on a contrac-tivity condition. We illustrate our control in the context of a tracking problem for nonholonomic systems in chained form