Research On The Measurement System Of The Characteristic Parameters On The Surface Of The Spliced Blackbody

As an important part of the optical subsystem in the guidance system,blackbody plays an important role in the acquisition performance and tracking characteristics of missile weapons.As a new structural blackbody,the splicing blackbody is installed in the seeker by splicing two semicircle blackbody.There will be a small gap at the splicing place of blackbody,and the angle and surface irregularity caused by splicing.In this paper,the gap width,included angle and flatness of stitched blackbody are studied deeply,and a measurement system based on machine vision and laser technology is simulated.In this paper,the current research status of gap width,plane angle and flatness measurement is analyzed at home and abroad,and the non-contact measurement method combined with machine vision technology and laser technology to measure characteristic parameters on the surface of the spliced blackbody is determined.At the same time,the overall scheme of the measurement system is designed,and the principle of key measurement methods is studied.For the measurement of the gap width,digital image processing technology combined with the frame selection average method is adopted to measure;for the measurement of the angle and flatness of the plane,the laser displacement sensor and the two-dimensional motion platform are adopted to record the coordinate data of the measurement point on the spliced blackbody.And the measured plane is fitted through least-square method to calculate the angle between the plane and flatness value.Secondly,the processing method of the gap image is studied in this paper,including the conversion of color and space,threshold segmentation,and filter denoising.In order to convert the gap image size to the actual size,two calibration methods of pixel size are studied.In order to improve the limitation of the measurement of the gap under multiple angles by the frame selection average method,an improved algorithm is proposed,and the accuracy and stability of the improved algorithm are verified through multiple experiments.In order to conform to the actual measurement,the gap images simulated by Auto CAD are printed,captured by camera and grouped to verify the reliability of the improved algorithm.Finally,after the functions of the measurement system software and other requirements are analyzed,the hardware simulation model and the simulation experiment scene are designed according to the selection of key hardware.And the measurement system master control software is developed to control the simulation experiment scene with information interaction.In order to conduct measurement experiments,the overall flow of the experiment is designed,and then the gap width,included angle and flatness parameters are measured through the simulation test scenarios and the developed control software,and the uncertainty of the measurement results is estimated to determine the final Measurement results.The results show that the error requirements under the simulation conditions are met,and that the measurement efficiency is high,and the operation is convenient.