Abstract:Gear tooth contact loss will occurs under heavy load condition,which causes the dynamic transmission error of the gear pair. The transmission error is the important factor cause the nonlinear vibration of cycloid bevel gear. It’s critical method to improve the vibration characteristics of gear system by prediction and calculation the dynamic transmission error of the cycloid bevel gear. In the paper, the dynamic response characteristic of cycloid bevel gear is researched under a range of operation speeds and torques condition. A new approach of surface integral and local FEM is proposed to solute the dynamic transmission error. And then, the strong nonlinear vibration characteristics of gear system are revealed. According to the approach, the nonlinear factors, such as the time-varied stiffness and meshing frequency variation, are no longer considered as the excitation. However, every time step of gear meshing is considered to calculate the dynamic mesh force and dynamic transmission error, and finally the nonlinear vibration characteristic of cycloid bevel gear is obtained. The approach can precisely present the key factors of the tooth, including the tooth geometry and tooth contact stress, which influences the dynamic characteristic of the cycloid bevel gear significantly and provides an effective method for the analysis of complex vibration characteristics of cycloid bevel gear transmission system.