Modelling, Simulation and Defect Diagnosis of an Epi-cyclic Gear

Gears are important part of rotating machineries for power transmissions. Faults in gear of machineries can lead to failure of machineries. It is thus important to monitor the conditions of gears to prevent break down of machineries. Modelling of machine is a virtual prototype which can be used to generate a large amount of data and can easily replace the expensive part of analysis of the system by using experiments. In this article, a model of epi-cyclic gear train is developed using multibody simulation software to study the effects of fault in its vibration responce. Here, missing tooth is created in the sun gear of epi-cyclic gear train. Design of gears is done using Catia V5. Different design and constraints between different subsystems is modelled using a multibody dynamics simulation software (MBS ADAMS). The simulated signal is then processed by Hilbert transform to obtain its envelope to remove the structural noise. Finally, FFT is done to get an inference of the condition of gear. The system’s Gear Mesh Frequency (GMF) is determined from the gear kinematics. In the envelope spectrum, high amplitude of peaks at GMF is observed in faulty as compared to healthy epi-cyclic gear train which manifests its health.