Accurate measurement positioning method based on calibration algorithm

Abstract

The invention discloses an accurate measurement positioning method based on a calibration algorithm, and the method comprises the steps: carrying out the conversion of any position and posture of a checkerboard calibration plate through a camera with a determined focal length, obtaining a plurality of images, converting the images into gray-scale images, carrying out the binarization processing, obtaining the angular points of the checkerboard calibration plate on the images, acquiring accurate sub-pixel coordinates of angular points of a checkerboard calibration plate of an image, calculating internal parameters of camera equipment for shooting a picture, acquiring external parameters such as rotation and translation matrixes of the camera equipment for shooting through a multi-point positioning method, and calculating and obtaining accurate positions of expected positioning points on the picture and world coordinate points corresponding to the expected positioning points. According to the method, the relative position of the real space corresponding to any pixel point on the image shot by the camera in any pose state can be obtained, accurate target position positioning is a very important link in precise instrument processing and daily measurement calculation, and improvement of the positioning and measurement precision and speed is a target and direction which are always effort in the industry.

Description

technical field [0001] The invention relates to the field of laser precision machining, in particular to an accurate measurement and positioning method based on a calibration algorithm. Background technique [0002] In the field of traditional image processing, it is very important to restore the precise position of the object itself through the image. For example, in the field of industrial measurement and positioning, accurate manual measurement is required to obtain actual parameters such as the length, width, and height of objects. The implementation of this online measurement method is cumbersome. For some large or small equipment that is difficult to measure or requires high precision It is difficult to obtain accurate parameters of objects through direct measurement. At present, there are many off-line measurement methods commonly used, such as microscope confocal scanning and other methods for measuring precision objects. Although this method has high precision, mos...

AI Technical Summary

Problems solved by technology

For example, in the field of industrial measurement and positioning, accurate manual measurement is required to obtain actual parameters such as the length, width, and height of objects. The implementation of this online measurement method is cumbersome. For some large or small equipment that is difficult to measure or requires high precision It is difficult to obtain the precise parameters of the object through direct measurement

At present, there are many off-line measurement methods commonly used, such as microscope confocal scanning and other methods for measuring precision objects. Although this method has high precision, most of the precision processing of objects requires coaxial measurement, and it is difficult for the processing platform and the microscope to perform simultaneous measurement. The axis is measured and processed at the same time, and the method of coaxial measurement has high requirements on hardware equipment and external conditions. It is necessary to accurately calibrate and match the processing platform and the object to be processed, and each time the processing platform or object to be processed needs to be reset. Both are calibrated and matched, so the coaxial method is not suitable for simultaneous accurate measurement during machining

[0003] Although paraxial measurement processing is also used, at present, methods such as image transformation or projection transformation are usually used. This image transformation method has low measurement accuracy and high requirements on external factors. The location is more accurate to take the ideal picture for subsequent measurement operations, the process is cumbersome and the cost is high

In the field of precise positioning, the relative position of the measured object can be obtained quickly and reliably through laser radar, but it requires related equipment and corresponding external conditions

Although the image can reflect the relative position and relative parameters of the actual object, due to the influence of shooting conditions and external factors, the actual parameters of the actual object cannot be accurately obtained through the image, and it is difficult to obtain the spatial position information

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