Prognostic Health-Management System Development for Electromechanical Actuators

Abstract

Electromechanical actuators have been gaining increased acceptance as safety-critical actuation devices in the next generation of aircraft and spacecraft. The aerospace manufacturers are not ready, however, to completely embrace electromechanical actuators for all applications due to apprehension with regard to some of the more critical fault modes. This work aims to help address these concerns by developing and testing a prognostic health-management system that diagnoses electromechanical actuator faults and employs prognostic algorithms to track fault progression and predict the actuator's remaining useful life. The diagnostic algorithm is implemented using a combined modelbased and data-driven reasoner. The prognostic algorithm, implemented using Gaussian process regression, estimates the remaining life of the faulted component. The paper also covers the selection of fault modes for coverage and methods developed for fault injection. Validation experiments were conducted in both laboratory and flight conditions using a flyable electromechanical actuator test stand. The stand allows test actuators to be subjected to realistic environmental and operating conditions while providing the capability to safely inject and monitor propagation of various fault modes. The paper covers both diagnostic and prognostic run-to-failure experiments, conducted in laboratory and flight conditions for several types of faults. The experiments demonstrated robust fault diagnosis on the selected set of component and sensor faults and high-accuracy predictions of failure time in prognostic scenarios.

Prognostics: a literature review

“…One of the most important prognostics system has been developed for EMA which plays a dominant rule in controlling surfaces of new-generation fly-by-wire aircraft and spacecraft in severe conditions [53,54]. EMA is a safety critical part.…”

Fault Diagnosis of Electromechanical Actuator Based on VMD Multifractal Detrended Fluctuation Analysis and PNN

“…Consequently, it is very meaningful to carry out the research on fault diagnosis algorithms of EMAs under variable working conditions. NASA Ames Research Center's researchers conducted failure mode and effect analysis of EMAs through extensive literature investigation, and the main fault modes of EMAs were obtained [1]. The researchers built the flyable electromechanical actuator (FLEA) test-bed, so that the normal data and fault data of EMA can be obtained through a large number of experiments [2].…”

EMA remaining useful life prediction with weighted bagging GPR algorithm

“…In the scheme of the next generation aircraft, more and more fly-bywire controls are used in contrast with traditional hydraulic controls and actuation methods [1,2,3,4,5], because mechanical and hydromechanical flight control systems are relatively complex and heavy. Moreover, both of these two systems require abundant backup to avoid failures and abnormal conditions.…”