FPGA-assisted high-precision, high-speed 3D shape measurement

Abstract

In order to achieve three dimensional (3D) shape measurement, improve measurement accuracy, a high-speed and high-precision FPGA architecture for phase measurement profilometry (PMP) algorithm is proposed. The system uses 12 sinusoidal fringes to achieve 3D shape measurement and corrects the inverse-phase of the projector to improve measurement accuracy. In addition, the coordinate rotation digital computer (CORDIC) algorithm is used to realize the arctangent function calculation, which not only improves the calculation speed, but also improves the phase calculation accuracy. The system utilizes the parallelism of FPGA and the superior performance of pipeline processing. It also redesigns the modules to greatly improve the speed of 3D reconstruction such as data buffer, phase wrapping, phase unwrapping, and point cloud. The results of experiments show that the method we proposed is faster than conventional methods.