Free vibration properties of rotate vector reducer

For RV reducer widely used in Robots, this work develops a lumped parameter model to investigate free vibration properties of general description. The dynamic model admits three planar degrees of freedom for each component and includes key factors affecting vibration such as involute and cycloid gear mesh stiffness, crankshaft bending stiffness and bearing stiffness. For the linear case, examine of the associated eigenvalue problem reveals the specific structure of vibration modes. The modes are classified into three types: rotational, translational, and planetary component modes. All vibration modes fall into one of these three categories. The unique properties of each type is examined which is analytically verified with candidate mode method. Furthermore, the work investigates effects of parameters, which include stiffness, mass, moment of inertia and crankshaft eccentricity, on natural frequencies of three vibration modes and crankshaft eccentricity is in particular scrutinized. It is helpful for understanding the relationship between parameters and vibration modes.