A reliable analytical navigation system based on symmetrical dynamic behavior of control channels

Abstract

This study develops an advanced fault recovery strategy to improve the reliability of an aerospace launch vehicle navigation system. The proposed strategy contains fault detection features and can reconfigure the system against common faults in the aerospace launch vehicle navigation system. For this purpose, fault recovery system is constructed to detect and reconfigure normal navigation faults operating as a soft sensor, based on the symmetrical dynamic behavior of the yaw and pitch channels of the vehicle. In the face of pitch channel sensor failure, the Auto Regression Exogenous model of the yaw channel of the vehicle is identified using the recursive instrumental variable methodology. Based on the symmetrical behavior of the aerospace launch vehicle in the yaw and pitch channels, the Auto Regression Exogenous model of the yaw channel is substituted by the dynamic model of the pitch one and consequently, the pitch-rate gyroscope output is constructed to provide fault-tolerant navigation solution. The novel aspect of paper is employing symmetrical dynamic behavior of the yaw and pitch channels as an online tuning of analytical fault recovery solution against unforeseen variations due to its hardware/software property. In this regard, a nonlinear model of the aerospace launch vehicle is simulated using specific navigation failures and the results verified the feasibility of the proposed system. Simulation results and sensitivity analysis show that the proposed techniques can produce more effective estimation results than those of the previous techniques, against sensor failures.