Real-time 3-D shape measurement with composite phase-shifting fringes and multi-view system

Area of Science:

• Optical Metrology
• 3-D Imaging and Reconstruction
• Computer Vision

Background:

• Fringe projection is a key technique for dynamic 3-D shape measurement in industrial applications.
• Existing high-speed methods often require specialized hardware or reduced pattern sets.
• Accurate dynamic 3-D measurement of complex shapes at full resolution remains a challenge.

Purpose of the Study:

• To develop a high-speed 3-D shape measurement technique for dynamic, arbitrarily-shaped objects.
• To achieve full sensor resolution without additional pattern projections.
• To enhance accuracy and speed in 3-D measurement systems.

Main Methods:

• Utilizes composite phase-shifting fringes and a multi-view system for 3-D reconstruction.
• Employs geometry constraints for independent corresponding point searching, eliminating the need for extra images.
• Incorporates phase analysis, triangular wave correction, and left-right consistency checks to refine 3-D data and fringe orders.

Main Results:

• The proposed method achieves a measurement speed of 120 frames per second (fps).
• Demonstrates capability for fast, dense, and accurate 3-D measurements using 25-period fringe patterns.
• Successfully handles occlusions and refines period orders through consistency checks.

Conclusions:

• The novel technique effectively addresses the challenge of high-speed, high-resolution dynamic 3-D shape measurement.
• The composite fringe and multi-view approach offers a robust solution for complex object measurement.
• Validated through experiments on static and dynamic scenes, proving its practical applicability.