System Design Of Line-structured Light Monocular Vision Measuring Two Plane Height Difference

Vision measurement technology uses a camera to capture the image of the target area,after digital image processing and calculate the measured value,with non-contact,automated features.Line-structured monocular vision measurement,which uses the laser emitter to emit line structure light projected onto the object to be measured,using a single camera to take pictures for active measurement.The system design of the line-structure light monocular visual measurement of the difference in height between two planes is aimed at the measurement of the height difference of the two parallel planes of the housing after the cell phone charger is pressed.The cross-laser is projected horizontally along the 45 degree horizontal plane to the object to be measured,and a single camera captures the image in the positive vertical direction of the object to be measured.By performing image processing on the area of the line structure light bar in the image,the center coordinates of each area are extracted,and the height difference between the two planes is measured according to the isosceles triangle principle.However,there are noises collected by the camera,reflection and diffusion exist on the material surface of the object to be measured,and the quality of the laser projector affects the imaging effect of the picture,thereby affecting the central coordinate extraction of the region of the line structure light bar.Therefore,the rationality of the measurement scheme design and the algorithmic processing of the captured light bar image are the key.This thesis understands the current status of research on structured light vision measurement at home and abroad,analyzes existing image filtering and segmentation techniques,and extracts structured light bar image centers.Introduce the measurement principle and design the measurement plan,analyze and process the edge of the light bar image,and extract the center coordinate of the light bar.The main research contents of this article are:(1)Introduce the status quo of structural light vision measurement at home and abroad.Introduce the research status of filtering and segmentation technologies and the structure of light and light strips in structured light.(2)Design Line Structure The visual measurement of the two-plane height difference of the mobile phone charger housing is measured by the three-dimensional surface model.Designing a camera,lens,and line-structured light generator.(3)Inflate,sum and intersect the internal holes of the line structure light bar,and divide the main area by using 8 connected areas and gray area thresholding method.Design the circular structure element to open filter and deburr the light bar..Design a rectangular structure element to divide and modify the light bar.(4)Analysis of the extraction of the geometric center,the extraction method of the energy center,and the center extraction of the light bar direction.Aiming at the image noise of camera noise,material surface reflection diffusion and projector quality,a method combining the threshold and moment to extract the center of the light bar is proposed.Has a strong adaptability to meet the characteristics of the extraction effect.(5)Three samples randomly selected from the labeled samples are divided into one,two,and three groups.Each sample individually marks the position of the measured four corresponding line structure light projections.Each of the three groups of samples was subjected to 20 repeated measurements in the visual measurement system.The experimental data shows that the actual data of each measurement data and mark changes within 0.02 mm.The measurement system accuracy error is fine-tuned and a mean-value error compensation method is proposed.The measurement system reaches a measurement accuracy of 0.02 mm,and the measurement accuracy is stable.