Vibration-Based Fault Detection of Accelerometers in Helicopters

Victor Girondin (1) , Mehena Loudahi (1) , Komi Midzodzi Pekpe (2) , Jean Philippe Cassar (2)

1 LAGIS - Laboratoire d'Automatique, Génie Informatique et Signal
2 STF - Systèmes Tolérants aux Fautes

Vibration-based monitoring is an approach for health analysis of helicopters. However accelerometers and other sub-elements that convert and transmit vibrations to the recording system must not corrupt the signal. These elements are prone to defects because of external injuries during flights or maintenances. In the presented paper, a method is proposed to tackle problems of loosening and mechanical shocks. The objective is to perform passive detection of accelerometer failures from the vibrations and whithout knowledge about previous recordings. Experiments of mechanical failures have been carried out on a shaker to reproduce in flight vibrations, and it appears that loosening and mechanical shocks introduce asymmetry and random peaks in the temporal vibrations. Loosening was succefully detected but mechanical shocks are much harder to detect because of strong dependances on vibratory environment. Loosening data sets from from flights confirm experimental observations and the proposed detection method allows to detect the fault with better performances than standard indicators.

Mots clés: Flight control; fault detection; Signal processing for FDI; Mechanical and electro-mechanical applications

Domaines: Automatique / Robotique; Vibrations [physics.class-ph]; Vibrations [physics.class-ph]

Victor Girondin, Mehena Loudahi, Komi Midzodzi Pekpe, Jean Philippe Cassar. Vibration-Based Fault Detection of Accelerometers in Helicopters. Fault Detection, Supervision and Safety of Technical Processes, Aug 2012, Mexico, Mexico. pp.Volume # 8 | Part# 1 | 720-725, ⟨10.3182/20120829-3-MX-2028.00049⟩. ⟨hal-00747788v1⟩