Real-time accommodation of actuator faults on a reusable rocket engine

Abstract

An intelligent control system for reusable rocket engines is under development at the NASA Lewis Research Center. The primary objective is to extend the useful life of a reusable rocket propulsion system while minimizing flight maintenance and maximizing engine life and performance through improved control and monitoring algorithms and additional sensing and actuation. The main result of this work is the successful integration and real-time demonstration of model-based fault detection with a reconfigurable control as a new technique for valve fault accommodation on a reusable rocket engine. The focus here is on detecting and accommodating a frozen (stuck in a fixed position) oxidizer valve during a down-thrust and up-thrust manoeuvre by examining fault parameters produced by the algorithm. The detection scheme estimates the position of the frozen valve as a function of the fault parameters. Real-time simulation results demonstrate the effectiveness of the approach for two fault scenarios during a typical throttling manoeuvre.