Sampled-Data Control of Nonlinear Systems with Delayed Control Inputs

We investigate the sampled-data control of nonlinear systems under delayed control action. Two nonlinear state feedback control algorithms are considered, both of which attempt to cause the system response to emulate that of a linear reference model. The "nonlinear gain scheduling" approach is based on a discretization of a linearization of the system. The "multirate feedback linearization" approach is based on an approximation to the nonlinear discrete-time equivalent system. As a requirement in both approaches is the controllability of the linearization of the discrete-time open-loop system, we show that this can be established directly from the continuous-time linearization of the open-loop system. Simulations are presested for a simple pendulum example.