A hybrid architecture for diagnosis in hybrid systems with applications to spacecraft propulsion system

Abstract

In this paper, we develop a hybrid approach for fault diagnosis in hybrid systems assuming that multiple faults may occur in both continuous dynamics and at the discrete level. In this approach, a diagnoser is designed for a discrete-event-system (DES) abstraction of the system. The DES abstraction is modified such that the actual condition of the system always remains a subset of the condition estimate provided by the DES diagnoser. Whenever the DES diagnoser fails to provide a certain condition for the system (or it is deemed to be necessary), a continuous diagnoser consisting of a bank of residual generators becomes active. Since the continuous dynamics is not used at all times for diagnosis, our approach reduces the online computing requirements of the diagnosis system. We also model a typical spacecraft propulsion system as a hybrid automaton and explain how our results can be applied to it.

An industrial information integration approach to in-orbit spacecraft

“…Many methodologies and techniques, such as Kalman filter, neural network, expert systems, multi-transform of time data series, Bayesian models and second-order sliding mode observer (Jonghee, Youdan, and Yee-Jin 2009;Li, Ma, and Khorasani 2006;Barua et al 2005;Harrington 1987;Hu, Qiu, and Iyer 2007;Lucas 2001;Davila, Fridman, and Levant 2005), have been proposed and implemented for data acquisition, processing and fusion to detect malfunctions, abnormalities or failures in complex systems. These new techniques play critical roles in expanding human being's capabilities in space exploration, especially, for the attitude and thrust controls of satellite systems (Joshi et al 2007;Crassidis, Markley, and Cheng 2007;Azarnoush and Khorasani 2007;Li, Ma, and Khorasani 2005;Mohammadi, Hashtrudi-Zad, and Khorasani 2007). For example, NASA developed a diagnosis reasoning software (Livingstone) based on a qualitative model; it was tested and applied in the satellites for earth observation.…”

A hybrid fault diagnosis and recovery for a team of unmanned vehicles

“…On the other hand, DES provides a powerful tool for modeling a wide variety of applications, and have been utilized to address the fault detection and recovery problems [6]- [8]. In the supervisory control framework that was proposed by Ramadge and Wonham [9], the DES is modeled as a generator of a formal language, which can be controlled through an external supervisor by enabling or disabling certain events (transitions).…”

Automatic sensor assignment of a supermarket refrigeration system

“…Both discrete faults and continuous faults are modeled as a mode in hybrid automata as in [7]. It is supposed that events that describe transitions from a normal mode to a faulty mode are unobservable.…”

“…Generally speaking, a hybrid system is a dynamical system with both continuous and discrete behaviours and non-trivial interaction between continuous evolutions and discrete transitions. Fault diagnosis of hybrid systems has been investigated recently, for a survey see [7], [8], [12]. Most of the available methods are in the area of passive diagnosis.…”