Fault-tolerant design in a networked vibration control system

Rocket fairing should be able to sustain a certain level of vibration during launch process and its time in orbit. In active vibration control, actuator failures may lead to control performance deterioration or even catastrophic accidents. For this purpose, a networked vibration control system is used to ensure the reliability of rocket fairing system in the presence of actuator failures. However, in the distributed control systems, the sensors, controllers, and actuators are normally dislocated, and the control signal exchanges among them are realized via network communications. Inevitably, network-induced delay often degrades control system performance. Therefore, it is highly necessary to minimize its detrimental effects on control system performance so as to achieve more robust control authorities. This paper deals with the fault-tolerant design issues for a rocket fairing vibration control system including both actuator failure compensation and network-induced delay compensation. A Luenberger canonical form based actuator failure compensation scheme is proposed to accommodate some typical actuator failures, whose values, pattern and time instants are uncertain. A time-delay compensation scheme is then implemented to reduce damaging effects caused by the sensor-to-controller delay.