Li Zeying, Liu Pengbo, Yan Peng
School of Mechanical & Automotive Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
Key Laboratory of High-Efficiency and Clean Mechanical Manufacturing, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China.
Micromachines (Basel). 2021 Feb 19;12(2):212. doi: 10.3390/mi12020212.
Various tools, such as biomedical manipulators, optical aligners, and ultraprecision manufacturing tools, implement nanopositioners that must be dynamically tunable to satisfy the requirements of different working conditions. In this paper, we present the design and analysis of a flexure-based nanopositioner with dynamically tunable characteristics for the implementation of a high-performance servomechanism. The nanopositioner is composed of four flexure beams that are positioned in parallel and symmetric configurations sandwiched between magnetorheological elastomers (MREs). The properties of MREs impart dynamicity to the nanopositioner, allowing the workspace, stiffness, and damping characteristics in particular to be tuned under the action of an external magnetic field. By utilizing elastic beam theory and electromagnetic field coupling analysis, kinetostatic and dynamic models of the proposed nanopositioner were established to predict the variable stiffness property and dynamically tunable characteristics. The models were validated by performing a finite element analysis. Herein, it is shown that the proposed nanopositioner model can actively adjust the trade-offs between the working range, speed, and sustained load capability by changing the magnetic field. The proposed dynamic tuning method offers new insight into the design of flexure-based nanopositioners for real applications.
各种工具，如生物医学操纵器、光学对准器和超精密制造工具，都采用了纳米定位器，这些纳米定位器必须能够动态调谐，以满足不同工作条件的要求。在本文中，我们提出了一种基于挠曲的具有动态可调特性的纳米定位器的设计与分析，用于实现高性能伺服机构。该纳米定位器由四个挠曲梁组成，它们以平行和对称的配置放置在磁流变弹性体（MRE）之间。磁流变弹性体的特性赋予了纳米定位器动态特性，使得特别是工作空间、刚度和阻尼特性能够在外部磁场的作用下进行调谐。通过利用弹性梁理论和电磁场耦合分析，建立了所提出的纳米定位器的静动力学和动力学模型，以预测其可变刚度特性和动态可调特性。通过进行有限元分析对模型进行了验证。在此表明，所提出的纳米定位器模型可以通过改变磁场来主动调整工作范围、速度和持续负载能力之间的权衡。所提出的动态调谐方法为实际应用中基于挠曲的纳米定位器的设计提供了新的思路。
