Two-line type tube spirit level bubble offset quantity measurement method based on image processing technology

Abstract

The invention discloses a two-line type tube spirit level bubble offset quantity measurement method based on image processing technology. The method comprises steps of in a way of automatically determining an area-of-interest, carrying out operation on original two-line type tube spirit level gray scale images so as to acquire an area-of-interest image; finding a bubble center and each thick blackline profile center in the area-of-interest image; calculating the distance between the bubble center and two thick black line profile centers closest to the bubble center; and finally, according toa calibration result, achieving measurement of the deviation quantity of the bubble center and two thick black line profile centers closest to the bubble center. According to the invention, in a way of machine vision, problems that time and labor are consumed and errors are big by use of eye identification can be effectively solved; the vertical distance value between the bubble center and two thick black line profile centers closest to the bubble centers is used for representing the actual deviation quantity, so the algorithm is highly creative and robust; and meanwhile, the method is simple,practical and high in precision.

Description

technical field [0001] The invention relates to the technical field of machine vision measurement, and relates to a method for measuring the bubble offset of a multi-line tube level based on image processing technology. Background technique [0002] In many industrial manufacturing activities, people often need to check the flatness of the surface of the object to be measured. Therefore, some measuring instruments with a tube level (such as a spirit level, etc.) are usually used to complete this type of precision measurement. The most widely used method is to judge whether the surface of the measured object is level by measuring the bubble offset in the tube level. There are many measuring instruments with tube levels on the market today that are used to test the flatness of the surface of the measured object. Bubbles in the level are detected and calibrated. The general calibration method is to place the measuring instrument with a tube level on a standard level testing p...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the deficiencies of the prior art, the present invention provides a method for measuring the bubble offset of a two-line tube level based on image processing technology. The method adopts the method of automatically determining the region of interest, and enters the bubble center to calculate the bubble offset. When measuring the center of a fixed area, use the image outline to find the center coordinates of the bubble center and the two sets of thick black lines, and measure the offset of the bubble center between the areas surrounded by each set of thick black lines; improve the measurement accuracy, and can be used at the same time Because machines replace humans to detect measuring instruments with two-line tube levels, it solves the problem of time-consuming, labor-intensive and large errors in human-eye recognition

Images