Binomial Self-compensation for Motion Error in Dynamic 3D Scanning
Geyou Zhang Ce Zhu Kai Liu
Phase shifting profilometry (PSP) is favored in high-precision 3D scanning
due to its high accuracy, robustness, and pixel-wise property. However, a
fundamental assumption of PSP that the object should remain static is violated
in dynamic measurement, making PSP susceptible to object moving, resulting in
ripple-like errors in the point clouds. We propose a pixel-wise and frame-wise
loopable binomial self-compensation (BSC) algorithm to effectively and flexibly
eliminate motion error in the four-step PSP. Our mathematical model
demonstrates that by summing successive motion-affected phase frames weighted
by binomial coefficients, motion error exponentially diminishes as the binomial
order increases, accomplishing automatic error compensation through the
motion-affected phase sequence, without the assistance of any intermediate
variable. Extensive experiments show that our BSC outperforms the existing
methods in reducing motion error, while achieving a depth map frame rate equal
to the camera's acquisition rate (90 fps), enabling high-accuracy 3D
reconstruction with a quasi-single-shot frame rate.