Receding Horizon Control for a Class of Discrete Event Systems with Real-Time Constraints

We consider Discrete Event Systems (DES) involving the control of tasks with real-time constraints. When event times are unknown, we propose a Receding Horizon (RH) controller in which only some future event information is available within a time window. Analyzing sample paths obtained under this scheme and comparing them to optimal sample paths (obtained when all event times are known), we derive a number of attractive properties of the RH controller, including the fact that it still guarantees all real-time constraints; there are segments of its sample path over which all controls are still optimal; the error relative to the optimal task departure times is non-increasing under certain conditions. Simulation results are included to verify the properties of the controller and show that its performance can be near-optimal even if the RH window size is relatively small.