基于图像技术的钢球精确计数与尺寸识别系统

Accurate Count and Size Recognition System of Steel Balls Based on Image Technology

为解决轴承钢球生产过程中,人工称重计数不准确,容易造成球面擦伤、混球等问题,提出了基于图像技术的钢球精确计数与尺寸识别系统。该系统采用CCD(Charge Coupled Device)工业相机连续拍摄计数盘中钢球的图像以计算钢球的数量,并识别钢球的尺寸。整个系统由进料通道、预计数盘、精确计数盘、CCD工业相机、单球补偿装置和计算机等组成。首先,钢球通过进料通道滚动至预计数盘,并且在预计数盘上呈单层排列。预计数盘的面积根据钢球的尺寸和数量可以调整,通过面积调整使预计数盘中的钢球数量小于等于所需要的钢球数量。预计数之后钢球进入精确计数盘,通过精确计数盘上方的CCD相机采集钢球图像,经过图像二值化处理及双灰度阈值算法精确计算钢球数量。根据精确计数的钢球数量与预定数的差值,采用单球补偿装置进行补偿,以准确获得钢球的预定数量。通过在划定的区域内进行相邻钢球的球心距离对比识别异常尺寸的钢球。经过样机试验证明,所设计的钢球自动计数与尺寸识别系统,可以覆盖直径为4.763~25.4 mm的钢球计数,其计数准确率和尺寸识别混球判断率均达到100%。LI Yanqing,HE Shaoxin,ZHAO Junxiao,LIU Shuangyu,REN Tao2(College of Mechanical and Electric Engineering,Changchun University of Science and Technology,Changchun 130022,China;College of Computer Science and Technology,Changchun University of Science and Technology,Changchun 130022,China)

An accurate count and size recognition system of steel balls is developed in order to solve the problems of inaccuracy of steel balls weighting and counting,steel balls spherical bruises,mixed balls during bearing steel balls production process. A CCD( Charge Coupled Device) camera is used in this system to get the images of the steel balls in the counting-plate,to calculate the quantity of the steel balls and recognize the steel balls of abnormal size. The system is composed of a feeding channel,an estimated count plate,an accurate count plate,a CCD camera,a single ball compensating device and a computer etc. The steel balls scroll to the estimated count plate through the feeding channel and they are arranged in one layer. The area of the estimated count plate can be adjusted according to the dimension and quantity of the steel balls. The aim of the adjustment is to ensure that the number of the steel balls on the estimated count plate is less than that of required. The steel balls will enter the accurate count plate after estimated counting. The steel balls images are captured by the CCD camera which is set above the accurate count plate. Then binarization is performed to get the binary images of the steel balls,and the double gray threshold algorithm is adopted to calculate the number of the steel balls. The single ball compensating device is used to compensate the number difference between the accurate counting and the number of being needed. The steel balls of abnormal size are recognized through comparing the distances between the center of two neighboring steel balls in a defined district of the accurate count plate one by one. According to the experiments of the prototype,the system can be used to count steel balls whose diameter are between 4. 763 mm and 25. 4 mm,the accuracy of counting and the determine rate of the abnormal size steel balls of this system are all up to 100%.