Model-based Shaft-Coupling PHM using Accelerometers with GearModT-Shaft Processing

Mechanical transmission couplings and shafts are used to transmit power in rotorcraft, Short Take-off and Vertical Landing (STOVL) aircraft, land, and marine propulsion systems. These components are susceptible to degradation and failure caused by extreme loads and temperatures, misalignment, and other secondary effects. Due to the critical nature of these components, regular and frequent inspections are often used to compliment statistical time based removal and offset risk. This results in large life cycle costs and reduced system availability. An on-board, real-time prognostic and health management (PHM) approach is proposed that will enable continuous monitoring of mechanical couplings and shafts to offset the shortcomings of traditional health management approaches. The proposed approach will utilize existing on-board PHM sensors (primarily accelerometers) to facilitate transition and enable easy integration of coupling PHM with other vibration monitored drive train components, such as gears and bearings, and reduce hardware complexity, signal processing and computational needs. These algorithms will be packaged as an embedded software module that can be fused with gear and bearing modules to provide a comprehensive PHM system for helicopter, STOVL and marine propulsion drive trains.