High-speed and high-accuracy 3D surface measurement using a mechanical projector.

Area of Science:

• Optics and Photonics
• Computer Vision
• Metrology

Background:

• Accurate and high-speed 3D surface measurement is crucial for various industrial and scientific applications.
• Existing methods often face limitations in speed, accuracy, or complexity.
• Developing a system capable of real-time, sub-pixel accurate 3D reconstruction remains a significant challenge.

Purpose of the Study:

• To present a novel computational framework for high-speed and high-accuracy 3D surface measurement.
• To enable absolute shape measurement with sub-pixel accuracy.
• To achieve 3D reconstruction rates up to 10,000 Hz.

Main Methods:

• Development of a custom-designed mechanical projector and two synchronized high-speed cameras.
• Capturing precisely phase-shifted fringe patterns for accurate data acquisition.
• Employing a stereo-vision method with encoded statistical patterns to generate a rough disparity map.
• Utilizing wrapped phase as a constraint to refine the disparity map for enhanced accuracy.

Main Results:

• The system successfully achieves high-speed 3D surface measurement at rates up to 10,000 Hz.
• Sub-pixel accuracy in absolute shape measurement is demonstrated.
• The synchronization of the projector and cameras ensures precise fringe pattern capture.
• The computational framework effectively refines disparity maps for accurate 3D reconstruction.

Conclusions:

• The proposed method offers a significant advancement in high-speed, high-accuracy 3D surface measurement.
• The system's performance is validated through experimental results.
• This technique has the potential for broad applications in fields requiring rapid and precise 3D data acquisition.