A MEMS-based real-time structured light 3-D measuring architecture on FPGA

• Published in: Journal of real-time image processing Vol. 21; no. 3; p. 98
• Main Authors: Zhou, Wenbiao, Jia, Yunfei, Fan, Luyao, Fan, Gongyu, Lu, Fengchi
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2024; Springer Nature B.V
• Subjects: Accuracy; Algorithms; Cameras; Computer Graphics; Computer Science; Confined spaces; Design; Digital signal processors; Field programmable gate arrays; Fourier transforms; Image Processing and Computer Vision; Light; Methods; Multimedia Information Systems; Pattern Recognition; Phase unwrapping; Polynomials; Real time; Signal,Image and Speech Processing; Wavelet transforms; MEMS-based structured light; 3-D measurement; Fringe projection profilometry; FPGA
• ISSN: 1861-8200; 1861-8219
• DOI: 10.1007/s11554-024-01477-x

With its its ability to non-contact measure three-dimensional information of objects and its extremely high accuracy advantage in close range, structured light 3-D measurement is widely used in various fields. However, some application scenarios, such as measuring moving objects and performing measurements in confined spaces, impose requirements for high speed and miniaturization in structured light 3-D measurement. Therefore, we propose a real-time structured light 3-D measurement system on FPGA. This system employs a four-step phase-shifting method to compute wrapped phases, complemented Gray code for phase unwrapping, and a cubic polynomial fitting approach for calculating the 3-D coordinates of points. We have proposed the optimized pipeline structure for each module. We have also proposed an optimized on-chip buffer structure to further improve throughput. The 3-D measurement speed of the proposed method can reach 76.9 fps, when the clock frequency is 100 MHz, and the image size is 2448 × 2048.