大型收获机械发动机孔组位置度误差在线检测方法

Online Method for Large-scale Harvester Engine Punch Combination Position Accuracy Measurement

发动机是收获机械的动力源,其安装位置精度将直接影响整机装配质量,进而关系机器的作业效率和可靠性。由于收获机械底盘机架结构复杂、表面粗糙度大,现有测量方法及设备难以满足大跨距孔组位置度误差测量需求,针对收获机械发动机安装孔位置度的自动化测量需求,提出了基于机器视觉的大跨距孔组位置度误差在线检测方法,通过建立孔组位置度误差模型,使用多部工业相机获取安装孔二维图像,通过相机在线标定、图像增强处理、特征提取、坐标变换等手段,实时测取并计算安装孔组之间的位置度误差。在此基础上,基于Lab Windows/CVI平台,开发了自动检测软件,实现了发动机安装孔位置度的快速检测。以某型玉米收获机底盘机架发动机安装孔组为对象开展了试验研究,结果表明,利用该方法能够有效获取安装孔组的位置度关系,建立的孔组位置度误差模型能够进行误差分析与评定,在分辨率和测量精度上均优于传统测量方式,检测效率较高,能够满足生产线自动化检测需求。

The engine is primary power source of harvester,and its punch combination position has a direct impact on machine assembly quality and further affections on operating efficiency and reliability of the whole machine.At present,the engine punch combination position measurement is mainly performed manually with quite low precision and bad consistency.Focused on the automatic measurement of engine punch combination position,a machine vision based online measurement method for engine punch combination position of large-scale harvesters was proposed in this paper through establishing a punch combination position error model.A certain number of cameras were used to capture the two-dimensional images of each energy mounting hole,and the punch combination position error was measured and calculated real-timely through online calibration,image enhancement,feature extraction,coordinate transformation and so on.On this basis,a measurement and control software was developed based on Labwindows/CVI,and realized the rapid measurement of punch combination position.In this paper,engine punch combination position of a certain type of harvesting chassis of corn harvester was studied.The experiment results showed that the punch combination position relationships could be achieved effectively,and the error analysis and assessment could be fulfilled by the established punch combination position error model.Furthermore,its measuring results were superior to traditional calipers measuring tools readings in resolution and accuracy with a highly efficiency.This proposed online measurement method could meet the demand of automated production-line measurements.