Co-design for control and scheduling over wireless industrial control networks

We investigate the co-design of a scheduler and controller for feedback control over wireless industrial hybrid protocol networks. These hybrid protocols incorporate possibilities for both contention-free and contention-based medium access to support real-time requirements and intermittent communications, respectively. We focus in particular on the possibilities and limitations of feedback control over hybrid networks that are based on the IEEE 802.15.4 protocol, where we propose a controller-scheduler co-design that utilizes both the contention-free and contention-based parts of the protocol. This controller-scheduler is designed to minimize a linear quadratic cost function where probabilities for successful transmissions in the contention-free and contention-based parts also are taken into account. Simulation studies illustrate that careful co-design of the scheduler-controller results in significant performance gains compared to round-robin heuristics.