行星滚柱丝杠动力学特性分析及试验研究

Theoretical Investigation and Experimental Study onPlanetary Roller Screw Dynamics

关键词:  行星滚柱丝杠  动力学特性  接触分析  试验研究  固有特性分析

Key words:  Planetary roller screw  Dynamic characteristics  Contact analysis  Experiment study  Natural frequency analysis

摘要:

准确的舵机模型是舵机系统控制及颤振分析的关键，为实现舵机模型快速而准确的控制，需要建立高精度的行星滚柱丝杠动力学模型。依据赫兹接触理论建立了考虑螺纹啮合刚度的行星滚柱丝杠动力学力学模型，搭建行星滚柱丝杠动力学特性试验台。试验结果表明:行星滚柱丝杠前两阶固有频率试验结果分别为195Hz和747Hz，与仿真结果误差小于6.7%，验证了模型准确性。研究了螺纹接触角和滚柱半径对行星滚柱丝杠啮合刚度以及行星滚柱丝杠的前两阶固有频率的影响。结果表明:螺纹接触角增加，会导致行星滚柱丝杠的螺纹啮合刚度及其第一、二阶固有频率增加；而滚柱半径的增加同样会使行星滚柱丝杠的螺纹啮合刚度增加，但其第一、二阶固有频率会在半径为某特定值时达到最大。

Abstract:

An accurate dynamic model of planetary roller screw (PRS) is a key point in actuator system flutter analysis and aeroelasticity. In order to control the actuator system rapidly and accurately， a high precision dynamic model of PRS is needed. A dynamic model of PRS considering thread meshing stiffness through Hertz contact theory was established. A PRS dynamic experiment was set up to verify the dynamic model. The results showed that the first two order natural frequencies were 195Hz and 747Hz. The error between simulation results and experiment results of the first and second natural frequency are all less than 6.7%. The performance about the thread contact angle and roller radius effect on meshing stiffness and the first two order natural frequencies were investigated. The results show that the thread meshing stiffness and the first two order natural frequencies increase with thread contact angle. The meshing stiffness also increases with roller radius but the maximum values of the first two order natural frequencies appear when the radius approaches some value.