Stability analysis of a two-channel feedback networked control system

In this paper we propose a novel stabilization analysis of networked control of a controllable linear time invariant plant by a non co-located controller communicating with the actuator and the sensors of the plant via wireless channels of an existing wireless LAN (WLAN). We consider a lossless forward communication channel connecting the controller with the actuator and a lossy feedback channel connecting the sensors with the controller, where data transfer through both these channels suffer from significantly variable channel access delays. Sufficient conditions, using parameter dependent Lyapunov functions and perturbation theorem, are proposed for guaranteeing asymptotic stability of the networked control system (NCS) by treating it as a perturbation of a linear discrete-time system with variable sampling intervals. The efficacy of our results for network control synthesis is demonstrated using numerical simulations of a rotary inverted pendulum.