织物表面导电线路喷射打印中微滴关键参数的视觉测量

针对织物表面打印导电线路中微滴的几何尺寸、速度等参数测量过程自动化程度低的问题,将视觉测量与微滴喷射技术相结合。利用高速相机对微滴喷射过程进行拍摄得到连续微滴图像。基于像素的阈值选取方法对微滴图像进行分割,得到微滴的二值图像,采用阶梯型边缘检测算法提取液滴边缘轮廓,获得单个微滴的面积、直径参数,根据面积和直径的关系计算出单个微滴的圆度参数,根据2帧微滴图像间的位移量计算出微滴的瞬时速度。实验结果表明:采用视觉测量法测得到的结果精度可达像素级,整个测量过程耗时短,可实现实时测量,为后续织物表面导电线路的精确成形提供了必要监测手段。

Visual measurement of key geometric parameters of droplet in circuit jet printing on fabric surface

This research was carried out targeting on the low degree of automation in the process of measuring the geometric size and speed of the droplets in the conductive circuit printed on the fabric surface by combing the technology of visual measurement and droplet injection. A high-speed camera was used to record the droplet ejection process capturing continuous droplet images. The pixel-based threshold selection method was used to segment the droplet images to obtain binary image of the droplets. The edge contour of the droplet was extracted by the step-edge detection algorithm, and the area and diameter parameters of a single droplet were obtained according to the relationship between the area and the diameter. The roundness parameter of a single droplet was measured, and the instantaneous velocity of the droplet was calculated based on the displacement between two frames of droplet images. The experimental results show that the accuracy of the measurement results obtained by the visual measurement method can reach the pixel level, the entire measurement process is not time-consuming, and real-time measurement is achievable, which would provide the necessary monitoring means for the subsequent precise formation of the circuit on the fabric surface.