双足差动摩擦箝位混合式压电驱动新原理和设计方法的研究

The positioning and driving techniques with centimeter-level stroke and nanometer-scale accuracy are in urgent need in high technology fields such as biomedicine, nanotechnology, aerospace and et al. Specific to the contradictory issues between large stroke and high precision for existing piezoelectric actuator, the hybrid piezoelectric linear motors with bipedal differential friction driving and clamping is proposed utilizing the principle of differential friction in combination with non-resonant piezoelectric actuation technology. The theory and method of non-resonant differential friction driving would be established by researches on the contact dynamical behaviors of single driving at different tangential speed. The mechanical restraint rules and control methods of bipedal synergetic clamping-driving would be explored by investigations on the static equilibrium characteristics and the dynamical coupling behaviors. By establishing the contact dynamical model of unipedal driving and the restraint mechanics model of bipedal clamping-driving, the structural dynamic topology optimization of the motor stator would be conducted with finite element method and variable density method, which aims at high stability and high resolution in wide frequency domain. The influence of stator structure, friction interface，exciting signal and et al on the motor performance would be ascertained and methods of matching these aspects would be investigated to lay the foundation for the design and manufacture of the motor. The piezoelectric driving principle and design methods proposed in this project will lead to high stability, large stroke and nanometer scale displacement resolution, which can promote the application of piezoelectric driving technology and the development of related areas.

生物医学、纳米技术、航空航天等高科技领域的发展迫切需要具有厘米级行程和纳米级精度的定位和驱动技术。针对现有压电作动技术未能在大行程内稳定地实现纳米级精度的问题，提出将差动摩擦原理和非共振压电作动技术相结合，构建双足差动摩擦箝位混合式压电直线电机。研究不同切向速度下单足驱动的接触动力学行为，建立非共振差动摩擦驱动的理论和方法；研究双足驱动的静力学平衡特性和动力学耦合特性，探索双足协同箝位驱动的力学约束机制和控制方法。通过建立单足接触动力学模型和双足箝位驱动约束力学模型，以宽频域内电机的稳定性和分辨率为目标，利用有限元法和变密度法对电机定子进行结构动力学拓扑优化设计，探明定子结构、摩擦界面和激励信号等对电机性能的影响规律和匹配方法，为该型电机的设计和制造奠定基础。本项目提出的压电驱动原理和设计方法能实现高稳定性、大行程和纳米级位移分辨率，促进压电驱动技术的应用和相关领域的发展。

针对生物医学、精密仪器、空间技术等高科技领域的发展迫切需要具有大行程和高精度的定位和驱动技术，而现有压电作动技术较难在大行程内稳定地实现纳米级精度的问题，本课题研究了将差动摩擦原理和非共振压电作动技术相结合的压电作动机理，并进一步解决了双足差动摩擦箝位混合式压电直线电机的关键技术难题。研究不同切向速度下单足驱动的接触动力学行为，建立非共振差动摩擦驱动的理论和方法；研究双足驱动的静力学平衡特性，探索双足协同箝位驱动的力学约束机制和控制方法。通过建立单足接触动力学模型和双足箝位驱动约束力学模型，以宽频域内电机的稳定性和分辨率为目标，利用有限元法对电机定子进行结构动力学拓扑优化设计，探明定子结构和激励信号等对电机性能的影响规律和匹配方法，为该型电机的设计和制造奠定基础。针对精密致动领域存在的大行程和高分辨率这一矛盾，研究分析了压电双足差动摩擦箝位原理及其实现方法，提出了惯性冲击原理型差动摩擦箝位直线电机，并对该类型电机的工作机理进行了研究和验证。通过对本课题提出的电机样机性能测试，该类型电机样机的最大行程可达20mm以上，最高位移分辨率接近10nm，最大输出推力可达5.3N以上。已经发表和录用文章10篇，其中SCI/EI源期刊论文4篇，核心期刊3篇，授权专利2件，另有5件发明专利正在实审阶段。综上，研究团队较好地完成了项目提出的研究目标，本课题提出的压电驱动原理和设计方法能实现大行程和纳米级位移分辨率，能促进压电驱动技术的应用和相关领域的发展。