Gear Pitting Diagnostics Under Various Operating Conditions by Exploiting Torque Signals

Condition monitoring of gears is crucial for early damage detection to prevent unexpected breakdowns in rotating machinery. Plenty of approaches have been developed for detecting faults in geared systems using signals acquired from accelerometers, acoustic emissions sensors, and oil debris sensors. However, the complicated working environment and constrained spaces within modern industrial drivetrains often pose challenges to sensor installation. In contrast, torque signals provide an alternative solution as torque transducers are integrated in some electromechanical systems. Despite their importance, research on gear fault diagnostics using torque signals is still limited. This paper explores using torque signals for gear pitting diagnostics. A signal processing method is proposed for torque signals, focusing on extracting residual signals from Time Synchronous Averaging (TSA) signals. Measurements are collected from a gear test rig at KU Leuven, where the speed signals, torque signals, and vibration signals are acquired via encoders, a torque transducer, and accelerometers, respectively. Both a healthy gear and a faulty gear (artificially induced pitting damage) are tested under different speed and load conditions. Furthermore, a comparative study on gear pitting diagnostics using torque and vibration measurements is investigated. The results highlight the potential benefits of using torque signals for gear pitting diagnostics via advanced signal processing tools.