基于亚像素图像块匹配方法的压电陶瓷驱动特性测量

Sub-pixel Image Block Matching Based Measurement on Driving Characteristic of a Piezoelectric Actuator

为了高精度地测量压电陶瓷的驱动特性,提出一种基于计算机视觉的亚像素图像块匹配位移测量方法。对困扰亚像素图像块匹配方法的三个重要因素:搜索区域大小、模板图像大小、亚像素拟合精度进行详细分析和试验,提出根据试验结果和微纳米图像序列的测量特点选择最佳的搜索区域、模板大小、匹配准则函数和亚像素拟合方法的原则;使用高精度纳米平台、高倍显微镜以及标准栅格所组成的试验系统对该方法进行位移测量精度的验证试验;使用改进的亚像素图像块匹配方法对实际的压电陶瓷驱动器的驱动特性曲线进行测量。结果表明,该方法得到的压电陶瓷驱动特性曲线符合物理分析结果;并且方法本身操作简单、测量结果可靠,能够满足高精度的微纳米测量要求。

In order to measure the driving characteristic of a piezoelectric actuator with high precision,a sub-pixel image block matching method of displacement measurement based on computer vision is proposed. Three important factors,including the searching region,the model size,and the fitting precision of sub-pixel,are analyzed and researched,and the most appropriate parameters are chosen with respect to both the experiment results and the measurement characteristic of micro/nano image sequences. The high-precision nano platform,the high power microscope and the standard grid are used together to validate the measurement precision of this method. The proposed method is used to measure the driving characteristic curve of a piezoelectric actuator practically. The experimental results of the piezoelectric actuator driving characteristic measurement are consistent with the physics analysis. Also,the proposed method,which is simple in manipulation and credible in measurement results,satisfies the requirement of high-precision micro/nano measurement.