Research On The Precision Optimization For The Monocular Structured Light 3D Measurement System

Optical 3D measurement has been widely applied to industry.The requirement of optical 3D measurement technology is much higher than before,especially in measurement accuracy.According to the 3D measurement system based on monocular optical structure,this paper researches deep into the system calibration,phase extraction and platform building and other aspects,to optimize the measurement accuracy.The main research contents are as follows:(1)The measurement principle and the mathematical model of the monocular structured light 3D measurement system are analyzed and the calibration and reconstruction model of the system are detailed in this paper.(2)A method of system calibration based on two-dimensional sinusoidal grating coding,and a method of 3D reconstruction based on one-dimensional sinusoidal gray coding are illustrated in this paper.On the basis of ensuring the measurement efficiency,the measurement error caused by the projector lens distortion is solved,and the measurement accuracy is improved.(3)The phase extraction technology is studied,and the gamma nonlinearity of the projector is proposed.The mathematical model about the influence of the gamma nonlinearity of the projector for the phase linearity is established,and the eight steps phase shifting method is proposed to eliminate the influence of the gamma nonlinearity on the phase calculation.(4)The analysis model of accuracy about the monocular structured light 3D measurement system is established.Based on the influence of the structural parameters and the focal length of the system on the measurement accuracy,an optimization scheme is proposed to select the structural parameters and focal length of the system.The simulation system is utilized to verify the feasibility of the analysis,which provides a theoretical guidance for the construction of the measurement platform.(5)Based on the above research results,the system measurement platform is set up,the actual measurement experiments are carried out,and the measurement accuracy of the system is analyzed.