Generally, in planetary gearbox diagnostics, transducers are placed on the gearbox case near the ring gear. The relative angular position of the planet gears with respect to the transducer is a pivotal information for the evaluation of vibration signals related to planet/sun gears. This angular position is usually unknown, or it is known with a large tolerance. The present work seeks to propose two alternative methods for the identification of the angular position of the planet gears with respect to the transducer. The first one is based on the study of how the power flows inside the Time Synchronous average of the ring gear, whilst the second method is based on a modified statistical parameter such as the Crest Factor. The effectiveness of these methods is assessed on the basis of actual vibration signals acquired from a faulty planetary gearbox.
On the time synchronous average in planetary gearboxes / D'Elia, Gianluca; Mucchi, Emiliano; Dalpiaz, Giorgio. - (2013), pp. 1-11. (Intervento presentato al convegno nternational Conference - Surveillance 7 tenutosi a Chartres nel October 29-30, 2013).