基于多层分布式电极的微小机器人静电薄膜电机驱动机理研究

Microrobots, with the dimension of several millimeters, are widely applied in, e.g., medical operation, industrial inspection, search and rescue, attracting a large number of researchers. However, conventional actuators--electromagnetic motors, if shrink to the small scale, are not adequate to support the microrobots, suffering from poor energy density, while other actuators in this size mostly are based on induced-strain mechanism, suffering from short-stroke, great nonlinearity, and control difficulties, and hence actuation is one of the primary challenges for microrobots. Electrostatic actuators do not have those problems, since the stator and slider of an electrostatic actuator are coupled by electrostatic field instead of material deformation. While shrink, electrostatic film actuators, nevertheless, are subject to nonlinearly decreasing effective actuation area ratio, and weak output force. To circumvent this problem, this work proposes a novel electrode structure (multiple-layer distributed electrodes) to avoid the difficulties and costs in the manufacturing of the components inside the ineffective area, increase the effective actuation area, and enable the scalability of the actuators. This project studies on the millimeter-scale electrostatic film actuators integrating multiple-layer electrodes, by focusing on the actuation mechanism. By systematically exploring the three key scientific problems in the novel actuators: the mechanism among electrical potential, electrostatic field, and electrostatic force, the kinematic model of the actuator’s electrical-mechanical system, and the transfer mechanism of errors of shape, position, and electric circuits in the actuation system, this project shows a new approach for long-stroke, high-precision, easy-control actuation of microrobots, and provides scientific proofs and fundamental theories for the basic core techniques of microrobot actuators.

毫米尺度的微小型机器人广泛应用于医疗、检测、救援等领域，是近年来机器人领域的研究热点之一。然而，传统的电磁型电机在该尺度下能量密度不足，其他大多数新型驱动方式存在行程短、运动非线性、控制较难等问题，故微型机器人的驱动是该领域首要难题之一。基于静电场耦合驱动的静电薄膜电机可解决以上问题，但其微型化过程中存在有效驱动面积占比急剧减小，无法满足微型机器人的驱动需求等问题。本研究提出一种新的电极构型（多层分布式电极构型）以大幅减小非有效面积，提升电机跨尺度性能，降低加工难度和成本。以多电极层微型静电薄膜电机为研究对象，围绕多电极层静电薄膜电机驱动机理，探索其基于静电场的电-场-力耦合机制、电机系统机-电耦合机制、非理想条件参数与其驱动性能耦合机制等关键科学问题，为微型机器人的大行程、高精度、易控制的驱动提供一条新思路，同时为微型驱动器关键共性技术提供科学依据和基础理论支撑。

静电薄膜电机是近年来的一个研究热点。但其微型化过程中存在有效驱动面积占比急剧减小，无法满足微型机器人的驱动需求等问题。本研究以多电极层微型静电薄膜电机为研究对象，围绕多电极层静电薄膜电机驱动机理，本项目已完成建立多电极层静电薄膜电机的电-力学耦合模型、面向微型静电驱动的多层级设计与动力学分析、非理想参数对微型静电驱动的影响研究等研究内容，并进行了实验验证。研究团队已发期刊论文10篇，会议论文1篇，其中包括International Journal of Robotics Research、IEEE Transactions on Robotics、Nature Communications、Soft Robotics（2篇）、IEEE/ASME Transaction on Mechatronics、IEEE Robotics and Automation Letters机器人领域顶级期刊论文7篇。申请专利6项。培养在新型电机、微型驱动以及微型机器人领域具有深入研究经验的博士生1名、硕士生5名。项目组已经完成了任务书中的全部研究内容。为驱动器这一机器人领域关键共性技术提供了新的理论分析方法和技术路径。