基于机器视觉的定向播种用玉米种粒精选装置研究

摘要

根据玉米定向播种对种粒的要求,设计了一种基于机器视觉的玉米种粒实时精选装置.阐述了装置的组成和工作原理,设计了不合格种粒吹除装置及吹除方案,提出了种粒图像动态检测方法,根据种粒图像RGB颜色特征,提取出种粒区域及其各颜色区域,结合种粒形态特征建立了周长、面积等20个检测指标,并通过测试统计确定了其合格范围,最终据此分析和完成了尖端露黑色胚部、小型、圆形、虫蚀破损、霉变等不符合定向播种种粒的判断.依据种粒粘连处两分界点沿轮廓线较近一侧的距离与两分界点间直线距离之比,大于单一种粒轮廓线上任意两点的对应值,来判断种粒粘连性.试验表明,合格性检测准确率为96％,粘连性判断准确率为99％,不合格种粒有效吹除率为98％.%In order to meet the requirements for corn seed from directional seeding,a kind of corn seed dynamic selection machine was developed based on image processing technology.Firstly,the composition and working principle of this machine were introduced,and the device of blowing unqualified corn seed as well as its method of completing the blowing was designed.Also the dynamic detection method of corn seed images was developed.And then through the analysis of RGB color feature of these images,the extracting solution of the whole seed area and different color areas of seed in a corn seed image was obtained successively.Meanwhile,combined with the analysis of corn seed morphological characteristics,totally 20 detection indicators were set up to describe the eligibility of corn seed,such as perimeter,area,long axis,short axis.And the acceptable range of above indicators was determined through test statistics.In view of the above,the eligibility judgment methods of the following types of seed were analyzed respectively and executed successfully:seed with black embryo exposed in the tip,small seed,round seed,worm-eaten and damaged seed,moldy seed and other seed which did not conform to directional seeding.Furthermore,two points on contour line near two joints of adhesive seed were obtained,and it can be found that the ratio of the shorter distance of them along the contour line to the linear distance of them was larger than the corresponding value of any two points on the contour line of a single seed,which according to the adhesive seed can be detected.In the experiment,the results showed that the eligibility detection accuracy of corn seed was 96％,the judgment accuracy of adhesive seed was 99％,and the efficiency of blowing unqualified corn seed was 98％.