Three-dimensional target and global unified calibration method for linear structured light profile sensor

Abstract

The invention discloses a three-dimensional target. The three-dimensional target adopts a three-dimensional square ring shape, 38 uniform sawtooth-shaped grooves are formed in each edge of the three-dimensional square ring, and a missing tooth is arranged in the middle of each side edge of the three-dimensional square ring; the cross section of each of the sawtooth-shaped grooves is isosceles triangle. The invention further discloses a global unified calibration method used for a linear structured light profile sensor and implemented through the three-dimensional target. The global unified calibration method for the linear structured light profile sensor comprises the following steps: the target meeting a field range is designed, and a corresponding two-dimensional precision translation stage is selected; then four sets of linear structured light profile sensor profile measurement systems are established and shoot light bar images on the target simultaneously from different positions in combination with the two-dimensional precision translation stage. According to the calibration method, acquired images are processed and calculated in the following process sequentially: feature point extraction, camera calibration and coordinate system unification, and calibration of the whole system can be completed.

Description

technical field [0001] The invention relates to a structured light three-dimensional vision detection technology, in particular to a global unified calibration method for a line structured light profile sensor. Background technique [0002] Structured light three-dimensional visual measurement technology has the advantages of non-contact visual measurement, high speed, high degree of automation, and good flexibility. Structured light 3D vision is based on the principle of optical triangulation, and calculates the surface profile of the measured object by calculating the offset information of various light mode feature points in the collected image. The optical projector projects a certain light pattern, which makes the structured light image information easy to extract, so the measurement accuracy is high, and it is widely used in the online detection of various industrial products. [0003] A typical line structured light vision sensor consists of a line structured light l...

AI Technical Summary

Problems solved by technology

However, it is difficult to process the three-dimensional target, the cost is high, and the accuracy is difficult to guarantee. If Zhang camera is used for calibration, the light plane equation needs to be calibrated at the same time.

The calibration process is more complicated, and the accuracy is difficult to achieve the expected effect

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