H_∞ Control Of Terminal Orbit Maneuvering For The Interceptor With Fault-tolerant Compensation

With the development of space technology, the satellite is playing an increasingly important role in modern information warfare, and many countries with strong military force have been researching on anti-satellite technology. Interceptor is an effective means of attacking satellite, and has been a hot topic for many scholars. This paper will research on control of terminal orbit maneuvering for the interceptor. If the launched interceptor’s thruster fails, it will be difficult to repair. So, the study of controller will focus on model of actuator fault and design of fault-tolerant compensation.The main contents of this paper are divided into four parts. First, obtaining the state space model of terminal orbit maneuvering for the interceptor based on C-W equations by simplifying the Newtonian dynamics differential equations in Hill coordinates. The state space model uses relative positions and speeds as state vector. Besides, it also contains Non-Circle Uncertainly(NCU) and energy-bounded noise. Second, designing a controller with sensor saturation and actuator multiplicative fault, and the controller ensures that the system is asymptotically stable and satisfies H_∞ performance, input-bounded while the actuator fault description parameters set is known. Third, considering that the actuator fault description parameters set is unknown, design a kind of sliding mode controller combined with actuator fault parameters adaptive estimation. The controller can guarantee system’s stability, H_∞ performance and input-bounded. Fourth, because that the relative position and speed of interceptor are hard to measure in real time, designing a non-fragile observer-based sliding mode controller with actuator plus fault. During the process of designing, state observer and fault-tolerant compensation are well combined. Also, the controller is able to make the system asymptotically stable and satisfy H_∞ performance, input-bounded.In this paper, three kinds of fault-tolerant compensation controllers are presented correspondingly with three different situations. The first two are concerned with actuator multiplicative fault, and the last is actuator plus fault. All of the controller’s designing methods consider NCU, energy-bounded noise and input-bounded. And the difference is introduction of sensors saturation, actuator fault parameter estimation and state-observer respectively. In addition, sliding mode control make the latter two controllers have better robustness against the model uncertainties, parameter variations and external disturbance.