Fig. 1. Classifications and typical applications of 3D shape measurement technique based on structured light projection. (a) Dot matrix structured light projection^[15]; (b) line structured light projection^[16]; (c) planar structured light projection^[17]; (d) medically assisted diagnosis^[18]; (e) industrial component testing^[19]; (f) digitization of cultural relics^[20]

Fig. 2. Measurement requirements of complex dynamic scenes. (a) Swing of the pocket watch; (b) vibration of the drum membrane; (c) rotation detection of engine blades; (d) vibration of the loudspeaker; (e) impacting experiment; (f) vehicle crash test; (g) collision experiment under force; (h) transient deformation analysis

Fig. 3. Analysis of material mechanical properties based on three-dimensional shape information of complex structures. (a) Structural mechanics, force analysis of honeycomb structures^[30]; (b) mechanics of materials, performance test of composite braided materials^[31], rotational stress test of alloy materials ^[32]; (c) Bionics, strain analysis of insect wing flapping^[29] and its numerical simulation^[28]

Fig. 4. Principle and progresses of dynamic 3D shape measurement technology based on fringe projection^[35-45]

Fig. 5. Typical high-speed imaging devices and techniques. (a) CUP^[54]; (b) STAMP^[59]; (c) 3D imaging based on event camera^[61]; (d) 3D imaging based on SPAD^[62]; (e) 3D imaging based on SPD^[63]

Fig. 6. Typical ultrafast structured light projection system. (a) Binary defocusing projection system^[88]; (b) array projection system^[35]; (c) rotary grating projection system^[89]; (d) time-encoded projection system ^[90]

Fig. 7. Flowchart of dynamic 3D shape measurement based on Fourier transform profilometry

Fig. 8. Typical dynamic measurement results based on FTP. (a) Liquid vortex^[116]; (b) vibrating loudspeaker^[117]; (c) rotating fan blade^[119]; (d) vibrating drum membrane^[38]; (e) flapping wing of microaircraft^[37]

Fig. 9. Dynamic measurement method based on temporal Fourier transform profilometry^[89]. (a) Rotating grating structured light projection device; (b) dynamic 3D shape reconstruction process

Fig. 10. Dynamic measurement method of improved temporal Fourier transform profilometry. (a) Measurement results of reference plane assisted TFTP method^[89]; (b) measurement results of three-frequency fringe assisted TFTP method^[124]

Fig. 11. Dynamic measurement method based on micro Fourier transform profilometry (μFTP)^[39]. (a) Measurement flow chart of μFTP method; (b) results obtained by temporal phase unwrapping method based on minimum projection distance

Fig. 12. High-speed 3D shape measurement results based on μFTP method^[39]. (a) Pistol shot on plates; (b) busted balloon

Fig. 13. Measurement example of three-step phase-shifting method. (a)-(c) Three-step phase-shifting fringe patterns; (d) wrapped phase diagram; (e) mean value of the fringe; (f) modulation of the fringe

Fig. 14. Schematic of binocular fringe projection measurement system

Fig. 15. Measurement results of typical dynamic scenes based on binocular fringe projection measurement system. (a) Glass resonance^[137]; (b) broken glass^[137]; (c) teared paper^[138]

Fig. 16. Binocular structured light system based on aperiodic fringe projection and typical reconstruction results. (a) Array projection system^[35]; (b) rotary grating projection system^[41]; (c) brick collapse^[35]; (d) airbag ejection^[41]

Fig. 17. Typical temporal phase unwrapping approaches based on two-frequency phase shifting. (a) Two-frequency method; (b) number-theoretical method; (c) two-wavelength method

Fig. 18. Typical measurement results of the multi-frequency phase-shifting method. (a) Simple pendulum swing^[152]; (b) beating of the isolated rabbit's heart^[40]; (c) dynamic and static isolated objects^[153]; (d) measurement of human motion posture^[154]

Fig. 19. Gray-coded-assisted phase-shifting measurement technology. (a) Measurement principle; (b) source of phase unwrapping error

Fig. 20. Phase unwrapping error correction method of Gray-coded-assisted phase-shifting technique. (a) Post-correction method; (b) complementary Gray code method^[156]; (c) tripartite phase unwrapping method^[157]

Fig. 21. Typical methods to improve the coding efficiency of Gray-coded-assisted phase-shifting technology

Fig. 22. Typical measurement results for dynamic scenes of Gray-coded-assisted phase-shifting technology. (a) Newton's pendulum impact^[166]; (b) block collapse^[157]; (c) blade rotation^[157]; (d) falling snowflake^[167]; (e) water balloons hitting iron mesh^[167]

Fig. 23. Fringe projection measurement method based on deep learning. (a) Single frame phase reconstruction ^[170]; (b) one-step phase unwrapping ^[178]; (c) temporal phase unwrapping ^[173]; (d) end-to-end 3D reconstruction ^[175]; (e) single-frame composited fringe 3D reconstruction ^[176]

Fig. 24. High-speed 3D shape reconstruction based on deep learning^[43]. (a) Flow chart of the method; (b) captured fringes and reconstruction results based on μFTP method; (c) captured fringes and reconstruction results based on μDLP method

Fig. 25. Large depth-of-field projection measurement systems based on improved projection mode. (a) Band-limited projection system^[192]; (b) multifocal projection system^[193]

Fig. 26. Parallel single pixel 3D measurement system^[200]

Fig. 27. Results of three-dimensional deformation measurement and strain analysis based on fringe projection measurement system. (a) Honeycomb structure^[202]; (b) multi-zone deformed structure; (c) laminated structure