Superimposed fringe projection for three-dimensional shape acquisition by image analysis.

Area of Science:

• Optics and Photonics
• Computer Vision
• Metrology

Background:

• Traditional fringe projection techniques struggle with complex geometries, requiring multiple acquisitions or projector repositioning.
• Shadow areas and undercuts on surfaces pose challenges for accurate 3D shape acquisition.
• Sequential or alternate projector use in fringe projection can lead to time-consuming processes and postprocessing difficulties.

Purpose of the Study:

• To develop an advanced image analysis technique for 3D shape acquisition.
• To overcome limitations of conventional fringe projection methods for complex surfaces.
• To improve the efficiency and accuracy of 3D scanning processes.

Main Methods:

• Simultaneous projection of luminous fringes from multiple projectors.
• Development of a phase calculation and unwrapping algorithm for continuous phase maps.
• Strategic orientation of projectors to ensure full surface coverage.

Main Results:

• Achieved faster acquisition speeds compared to traditional methods.
• Successfully addressed challenges posed by undercuts and shadow areas.
• Eliminated postprocessing issues related to matching disparate point clouds.

Conclusions:

• Simultaneous fringe projection offers a robust solution for 3D shape acquisition of complex objects.
• The developed technique enhances efficiency and simplifies the 3D scanning workflow.
• This method provides accurate and continuous 3D surface data, even for challenging geometries.