基于机器视觉的重复定位精度测量技术

Repeat positioning accuracy measurement technology based on machine vision

重复定位精度是机床、机械手、工件台等工业设备的重要指标之一,它直接影响零件加工的一致性以及生产设备工作的可靠性,为此对设备的重复定位精度进行测定是评估设备能否满足精密产品生产需求的首要工作。而目前重复定位精度的测量主要有千分尺和激光干涉仪,但千分尺具有测量、读取数值不方便以及测量精度不高的缺点,而用激光干涉仪测量成本又较高。在设备的实际生产过程中,为了能够方便且又能精确的测定其重复定位精度,提出一种基于机器视觉的重复定位精度测量方法,该方法测定方便,测量精度达到亚像素级且可控,其随着测定相机分辨率的提高而提高,可以用于精度要求在微米级以下的设备的重复定位精度测定。

Repeat positioning accuracy is an important indicator of machine tools, robots, workpiece table and other industry equipment, which directly affect the machining consistency of a number of parts and the reliability of production equipment. So, in order to evaluate equipment can meet the production requirements, measuring the repeat positioning accuracy is necessary. Currently, the measurement of repeat positioning accuracy is mainly by micrometer or laser interferometer, but micrometer is inconvenient and precision is not high, while with laser interferometer the cost is higher. This paper presents a repeat positioning accuracy measurement method based on machine vision, the measurement method is convenient and measurement precision reached sub pixel controllable, it increased along with the improvement of measuring camera resolution and can be used for measuring the repeat positioning accuracy which the requirement is under micron.