Rapid calibration method of line-structured light vision sensor based on space plane restriction

Abstract

The invention discloses a calibration method of a line-structured light vision measuring sensor based on the space plane restriction, comprising the following calibrating steps: placing a two-dimensional planar target in a camera field range; collecting a group of images of multiple characteristic circles at the different positions on a two-dimensional target panel; determining the target topological relation; and synchronously completing the internal parameter calibration and the light planar calibration of a camera. In the process of the light planar calibration, substantial quantity of line-structured light planar three-dimensional points can be easily extracted by utilizing a camera imaging model and the restraining provided by the space plane formed by each position target; and planar fitting is carried out on the three-dimensional point set based on a principal element analytical method, so as to obtain an equation of the light plane in the coordinate system. The calibration method of the invention has simple operation and reliable result, is suitable for field calibration, and can satisfy the requirements of the line-structured light vision high-precision detecting tasks.

Description

technical field [0001] The invention relates to a line structured light vision measurement system, in particular to a fast calibration method for a line structured light vision sensor based on spatial plane constraints. Background technique [0002] Line structured light vision measurement technology is a non-contact active sensing measurement technology, which has the advantages of simple structure, good flexibility, strong anti-interference, rapid measurement, and easy extraction of light strip image information. It has important significance and broad application prospects in high-speed visual measurement, industrial inspection, reverse engineering and other fields. [0003] The calibration of line structured light vision sensor is a key technology in the field of line structured light vision measurement technology. At present, the main commonly used calibration methods are: wire-drawing method and sawtooth target method. The calibration points obtained by these two cali...

AI Technical Summary

Problems solved by technology

At present, the main commonly used calibration methods are: wire drawing method and sawtooth target method. The calibration points obtained by these two calibration methods often have low accuracy and a small number, which limits the improvement of calibration accuracy.

There is another calibration method based on the mechanical adjustment method of the target surface. The realization of this method requires a precision mobile platform, which is expensive, inconvenient to operate, and time-consuming to calibrate. Although high-precision calibration points can be obtained through this method, it is not suitable for On-site calibration

Another calibration method is to use the cross-ratio invariance to extract the fixed point of the structural cursor. This method can obtain high-precision calibration points through high-precision three-dimensional calibration targets, and is suitable for on-site measurement. However, the three-dimensional processing accuracy of the target requires higher

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