Design And Realization Of Positioning Error Compensation System For Image Measuring Instrument

With the development of industry,factory product measurement has higher and higher requirements for measurement accuracy and efficiency.As a high-precision instrument,the image measuring instrument has been widely studied in the industry on how to reduce its error and improve its accuracy.The method of constructing mathematical model and using software to complete the error compensation of image measuring instrument is widely used in the industry due to its economic and high efficiency.A line ruler with high accuracy,strong stability,low thermal expansion coefficient,and good corrosion resistance,is often used in length measurement tools as a measurement and calibration optical component.The positioning error compensation method of the image measuring instrument using the line ruler,that is,the error compensation based on interaction,requires manual data acquisition,construction of mathematical models,and design software to correct the system.When manual data acquisition is performed,sometimes due to the line Problems such as incorrect placement of the ruler and deviation of manual readings have reduced the accuracy of the final error compensation.Automatic error compensation combines the line ruler error compensation method with image recognition,and there is no strict requirement for the line ruler's placement.First,preprocess the line ruler image,grayscale and bilateral filtering are used to reduce image noise,and select the binarization threshold through the maximum inter-class variance;then perform line rule image recognition,and use the contour tracking method to identify the numbers in the image.After segmentation,the linear detection algorithm is used to extract the scale information in the line ruler image.The number recognition uses the pixel point matching method to identify individual numbers,and then combines the individual numbers according to the digital proximity relationship;the movement control of the image measuring instrument platform uses an equal-spacing displacement strategy that simulates manual data collection,and an arbitrary-spacing displacement strategy is designed for the insufficient number of sampling points and insufficient flexibility;finally,the collected data is used to construct a mathematical model: linear compensation function and segmented compensation function to complete positioning error Compensation.The system finally realizes the error compensation method based on interaction and the automatic error compensation method,and completes the positioning error compensation system of the image measuring instrument.Compared with the error compensation method based on interaction,the automatic error compensation method has the advantages of no manual intervention,higher efficiency and more stability.