Li Zheng, Zhao Liang, Guo Peng, Wang Zhe
School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, China.
Sci Prog. 2021 Jan-Mar;104(1):368504211002356. doi: 10.1177/00368504211002356.
This paper proposes a new research method in view of the rare research on the contact state of hybrid drive multi-degree-of-freedom motor. Firstly, the basic principle and structure of hybrid drive motor are introduced. The air gap magnetic field model and electromagnetic torque model of permanent magnet rotor are obtained by analytical method. Static analysis of piezoelectric stators are carried out by stress-strain relationship. According to the analytical method and the spatial geometric relationship, the piezoelectric driving torque under different driving conditions is obtained. Introducing Hertz contact theory and Mindlin theory, combined with piezoelectric driving torque, electromagnetic driving torque and load torque to analyze the friction situation. A friction interface model considering the dynamic nonlinearity of friction coefficient and the nonlinear change of friction force distribution is established. Finally, using Matlab software, the friction distribution diagram of the contact surface of the hybrid drive three-degree-of-freedom motor under different driving and motion states is obtained. The analysis results verify the rationality of the electromagnetic piezoelectric hybrid driven three-degree-of-freedom motor. It shows that the contact state of the three sets of piezoelectric stators are determined according to the driving condition and load, the relative speed of the piezoelectric stators and the spherical rotor is proportional to the frictional force. It provides an idea for the research of contact state of hybrid drive multi-degree-of-freedom motor, and also lays a basis for further optimizing the friction interface of this kind of motors or actuators.
针对混合驱动多自由度电机接触状态研究较少的情况，本文提出一种新的研究方法。首先介绍了混合驱动电机的基本原理和结构。通过解析法得到了永磁转子的气隙磁场模型和电磁转矩模型。利用应力 - 应变关系对压电定子进行了静态分析。根据解析法和空间几何关系，得到了不同驱动条件下的压电驱动转矩。引入赫兹接触理论和明德林理论，结合压电驱动转矩、电磁驱动转矩和负载转矩来分析摩擦情况。建立了考虑摩擦系数动态非线性和摩擦力分布非线性变化的摩擦界面模型。最后，利用Matlab软件得到了混合驱动三自由度电机在不同驱动和运动状态下接触表面的摩擦分布图。分析结果验证了电磁 - 压电混合驱动三自由度电机的合理性。结果表明，三组压电定子的接触状态根据驱动条件和负载确定，压电定子与球形转子的相对速度与摩擦力成正比。这为混合驱动多自由度电机接触状态的研究提供了思路，也为进一步优化此类电机或执行器的摩擦界面奠定了基础。
