Research On Adaptive Fault-tolerant Control System Of Reusable Launch Vehicle

With the development of science and technology, the focus of the modern aerospaceengineering is becoming the reused aircraft. The main advantage of the reusable vehicle(RLV was, Reusable Launch Vehicle), including lower costs, easy launch process andimprove the transmission frequency, which is a power return and glide path landingvehicle. But considering about RLV’s repeated use and poor working conditions, thepossibility of faults happened is also greatly improved. This paper is about the theory anddesign methods for fault-tolerant control scheme in RLV. It uses the adaptivefault-tolerant control method to ensure that the attitude control system can still normaloperation when the sensor and actuator occurs once fault. The research includes the mainfollowing aspects:1. Analyze the characteristics of RLV, build the RLV nonlinear motion model anddefine the coordinate system and angle which are used during the modeling process.2. Consideration about the failure mode of sensor and actuator, on the basis of oncefailure mode, in accordance with their respective characteristics to create a controlsystem expression.3. The adaptive fault-tolerant control program is based on using model state observe.Separate discussed the conditions which the system expression of sensors and actuatorsremained stable. In this process, transform the control system expression into a linearmatrix inequality (LMI), and the sufficient condition of the stability of the control systemis ensured by the solution of LMI.4. Finally, analysis the RLV specific hardware failures and simulate, and simulationfor sensor and actuator failures, which verifies the effectiveness and feasibility offault-tolerant controller. The work process of RLV with fault conditions is simulated andverified by nonlinear6-DOF mathematical simulation.