Design and Error Calibration of a Machine Vision-Based Laser 2D Tracking System.

Area of Science:

• Metrology and Precision Engineering
• Optical Measurement Systems
• Machine Vision Applications

Background:

• Laser trackers are crucial for precise geometric measurements, offering range, accuracy, and real-time performance.
• Traditional laser trackers face challenges with low beam recovery efficiency.
• Existing systems often rely heavily on optical coaxiality and mechanical precision.

Purpose of the Study:

• To develop a novel two-dimensional laser tracking system to overcome the limitations of conventional designs.
• To improve beam recovery efficiency in laser tracking applications.
• To enhance the precision and reliability of geometric measurements.

Main Methods:

• Integration of a machine vision module into a two-dimensional laser tracking system.
• Implementation of a unique off-axis optical design separating distance measurement and laser tracking paths.
• Development of a tracking head error calibration method using singular value decomposition (SVD) and experimental point cloud data.

Main Results:

• The proposed system demonstrates significantly improved beam recovery efficiency.
• The off-axis design reduces dependency on optical coaxiality and mechanical processing precision.
• Experimental testing confirmed a relative positioning accuracy of less than 0.2 mm (RMSE = 0.189 mm) at 1.5 m.

Conclusions:

• The developed two-dimensional laser tracking system offers an effective solution for high-precision geometric measurement.
• The integration of machine vision and an off-axis optical design enhances system performance.
• The SVD-based calibration method contributes to improved accuracy and reliability.