Method for Fault Diagnosis of Missile Actuator Based on Analytical Redundancy

A fault diagnosis method is proposed for missile actuator during flight, which is based on analytical redundancy. The concept of analytical redundancy is employed in this approach. By analyzing the mathematical model of missile attitude control system, theoretical values of cant angles for four missile nozzles could be obtained, and by understanding the structure and function of missile actuators, the corresponding output values of displacement feedback potentiometers which reflect the cant angles would be gotten. Further, the residuals for missile actuators online fault diagnosis could be obtained by functional analytical redundancy between theoretical and output values. Finally, the fault of missile actuator could be determined based on the change of residuals. Simulation shows the validity of the proposed method for missile actuator online fault diagnosis.