基于高频压电驱动/微视觉反馈的柔顺定位平台动力学与控制研究

A compliant positioning stage based on high-frequency piezoelectric drive and micro-vision feedback is a novel precision positioning stage. It has broad application prospects in engineering fields such as cell arrangement and dispensing, micro-nano fabrication and optical element manufacturing. Compared with the traditional piezo-driven compliant positioning stage, it has the following two advantages：one is that high-frequency voltage input can be applied for high-frequency piezoelectric drive; the other is that non-contact measurement with multiple degrees of freedom eliminates the need to arrange sensors at every degree of freedom of the stage, simplifying the structure of stage. The project always focuses on the application requirements of the new stage and the following contents are studied: the relationship between input frequency (input rate), voltage and output displacement is analyzed and the rate-dependent hysteresis model is established; a dynamical model of the novel stage based on rate-dependent hysteresis model is presented by considering the influences of pre-loading device and voltage amplifier; a full closed-loop control is designed based on micro-vision feedback; software and hardware experimental platforms are build to verify and improve the proposed dynamical model and control. This project aims to solve the problems of dynamic modeling and control in the practical applications of the novel stage, and to develop and establish new technologies and methods for the visual feedback electromechanical system.

基于高频压电驱动/微视觉反馈的柔顺定位平台是一种新型精密定位平台，在细胞排列和分装、微纳米加工、光学元件制造等工程领域具有广阔的应用前景。与传统的柔顺定位平台不同，新型平台具有以下两个优点：采用高频压电驱动，能够适用于更高频率的电压输入；采用多自由度非接触式测量，无需在平台的各个自由度布置传感器，简化了结构。本项目始终围绕新型平台的应用需求，研究以下内容：分析压电陶瓷输入频率（输入速率）、输入电压和输出位移之间的关系，建立其动态迟滞模型；基于压电陶瓷动态迟滞模型，综合考虑预紧装置和电压放大器的影响，描述柔顺定位平台的综合动力学特性；基于计算机微视觉反馈，设计新型柔顺定位平台的全闭环运动控制；搭建软硬件实验平台，验证并改进所提出的动力学建模与控制方法。本项目旨在解决新型柔顺定位平台实际应用中的动力学建模与控制问题，发展并建立适用于视觉反馈机电系统的新技术与新方法。

本项目围绕着基于高频压电驱动的柔顺定位平台在细胞排列和分装、微纳米加工、光学元件制造等工程领域的应用需求，开展了以下研究工作：针对高频激励下压电陶瓷复杂迟滞非线性，在经典迟滞模型的基础上，优化建立了多种高精度动态迟滞非线性模型，包括改进型Duhem模型和通用型Bouc-wen模型。针对传统伪刚体模型无法直接精确地描述圆梁型铰链的末端运动轨迹，通过引入互相垂直的线性弹簧，提出了一种通用型的PPRR伪刚体模型。该模型能够实现对圆梁型和直梁型两种铰链末端运动轨迹高精度描述，为后续圆梁型铰链的应用奠定了理论基础。大转角和运动解耦是柔顺机构优化设计两大难点，针对这一问题，通过引入曲柄滑块设计理念，创新性提出了一种双行程高精度的纯转动柔顺定位平台，该平台由上中下三层机构嵌套组成，包含大行程和小行程两种结构，实现了大行程、高分辨率，运动解耦功能。Z型铰链作为一种新型柔顺铰链，具有高放大比和改变运动方向的优点，将其与桥式机构相结合，设计了一种XYZ三自由度双向移动柔顺定位平台。该平台具有结构紧凑、大行程、双向移动的优点。针对精密运动控制研究，本项目首先设计一种带有扰动补偿的离散滑模控制策略，然后其与数据驱动控制相结合，提出了一种无模型的离散滑模控制策略。本项目的研究成果将会为基于高频压电陶瓷驱动的柔顺定位平台设计与控制研究提供新理论和新方法。