Optical Target Projector: Principle of Functioning and Basic Performance Test

Area of Science:

• Metrology
• Optical Engineering
• Industrial Photogrammetry

Background:

• Harsh industrial environments (high temperature, contamination, toxicity) necessitate advanced metrology solutions.
• Optical projectors offer a novel approach to photogrammetric target identification.
• Traditional photogrammetry targets face limitations in demanding industrial settings.

Purpose of the Study:

• To analyze the principles, optical characteristics, and advantages of optical projectors in industrial photogrammetry.
• To establish performance test methods for optical projectors as photogrammetric targets.
• To evaluate the accuracy and reliability of using optical projector points in industrial measurements.

Main Methods:

• Analysis of optical projector principles and optical characteristics.
• Conducting basic property tests (brightness, roundness).
• Developing and implementing performance tests including coincidence accuracy, measurement repeatability, surface precision, and laser tracker comparison.

Main Results:

• Coordinate measurement repeatability of 0.010 mm and surface measurement precision of 0.007 mm achieved with optical projector targets.
• Performance comparable to retro-reflective targets, demonstrating high reliability.
• Measurement accuracy is influenced by object color, particularly for black surfaces.

Conclusions:

• Optical projector points are a viable and reliable alternative to traditional targets for industrial photogrammetry.
• The technology is applicable in challenging environments where conventional methods falter.
• Further research should consider object surface properties for optimal application.