超声电机直驱的电动物镜控制方法

针对超声电机直接驱动的显微镜物镜为满足系统整体结构紧凑、快速和准确定位的需求,采用小型光电耦合器设计了位置检测传感器,配合遮挡片实现了物镜位置和物镜转换器运动方向的检测。采用传统比例-积分-微分控制(proportion-integral-derivative control,简称PID)和模糊控制提出了并行切换控制策略,将两者结合建立了宏微相融合的预测控制方法,实现了物镜转换器的高精度、快速切换控制。在嵌入式控制系统中实现了所设计的控制算法和策略,并进行了物镜自动切换控制实验。实验结果显示,采用笔者提出的定位结构和控制方法,电动物镜转换器的重复定位误差小于0.015°,定位时间小于3s,满足自动显微镜系统中对电动物镜转换器重复定位精度的要求。

The Control Method of Ultrasonic Motor Direct Driving Motorized Revolving Nosepiece

The motorized nosepiece objective of a microscope objective lens driven by an ultrasonic motor needs to quickly and accurately switch with compact structure. In light of ultrasonic motor direct driving, a sensor of structure with two parallel photo-couplers was proposed. Based on the structure, a combination of predictive control methods was proposed to achieve high accuracy and detect direction of rotation. Based on the classical proportion, integration and differentiation(PID) control and fuzzy control strategies, a predictive control method combining macro-control and micro-control was proposed to quickly and accurately realize switch revolving nosepiece. The control algorithms and strategies implemented in embedded control systems were used in the switch experiment. Experimental results show that with the proposed structure and control method, repeat positioning accuracy of the motorized nosepiece was less than 0.015° and positioning time was less than 3 s, which meets the requirement of motorized nosepiece repeat positioning accuracy of the automated microscope system.