Real-Time Adaptive Control for Uncertain Networked Control Systems

L₁ adaptive control is an appealing technology for control of systems in the presence of uncertainties. It addresses the issue of providing guaranteed transient performance and robustness for a class of adaptive architectures. This technical note studies the real-time output-feedback L₁ adaptive tracking over real-time networks. Event-triggered communication protocols are presented to schedule data transmission between the plant and the controller. We show that under the proposed scheme the difference between the states of the resulting networked control systems and an ideal model is uniformly bounded, and the bound can be further reduced by improving the communication quality. Stability conditions, in terms of event thresholds, allowable transmission delays, and control parameters, are provided, which can serve as guidance in real-time scheduling.