Adaptive Binocular Fringe Dynamic Projection Method for High Dynamic Range Measurement

Sensors (Basel). 2019 Sep 18;19(18):4023. doi: 10.3390/s19184023.

Abstract

Three-dimensional measurement with fringe projection sensor has been commonly researched. However, the measurement accuracy and efficiency of most fringe projection sensors are still seriously affected by image saturation and the non-linear effects of the projector. In order to solve the challenge, in conjunction with the advantages of stereo vision technology and fringe projection technology, an adaptive binocular fringe dynamic projection method is proposed. The proposed method can avoid image saturation by adaptively adjusting the projection intensity. Firstly, the flowchart of the proposed method is explained. Then, an adaptive optimal projection intensity method based on multi-threshold segmentation is introduced to adjust the projection illumination. Finally, the mapping relationship of binocular saturation point and projection point is established by binocular transformation and left camera-projector mapping. Experiments demonstrate that the proposed method can achieve higher accuracy for high dynamic range measurement.

Keywords: adaptive binocular fringe dynamic projection; binocular calibration; high dynamic range; structured light sensor; three-dimensional measurement.