Dependable control systems with self-recovery constraint

A novel constrained-state feedback control design method for duty-standby controllers of a dependable control system is presented in this paper. The dependable control system is a replacement for the classical reliable control system which has been developed for wired and analog systems. As an alternative to the control summation in reliable control systems, only one controller is active at any one time in a dependable control system. This will make it compatible with the duty-standby architecture of dependable computer systems that run the control algorithm. The automated managing of duty-standby controllers is challenging, especially in wireless sensor and actuator networks, owing to the scarcity of both information and processing resources. The solutions proposed in this paper are effective and feasible, as taking into account both state- and control-incremental constraints, and simply involving a static state-feedback strategy to minimize the computational demand in implementations. The state feedback gains are synthesized to fulfill the strict requirement on the two incremental constraints. As a result of that, the duty-standby controllers will be able to operate independently, while assuring the closed-loop system stability with a newly introduced self-recovery constraint. For a dependable control system, the employed self-recovery constraint is a quadratic constraint with respect to the control and state increments.