Modeling And Calibration Of Structured-light-based 3D Measurement System

The 3D measurement technology based on structured light is the most practical non-contact 3D measurement technology. It is important in temporary measurement, and is attached importance to, is an effective approach to solve non-contact 3D measurement problems. Traditional contact measuring will damage object surface and can not measure object with soft surface, but 3D digital measurement technology based on line structured light makes up the limitation and can realize 3D measurement of any object surface shape.An improved modeling method is proposed for structured-light-based 3D measurement, thinking intrinsic and extrinsic parameters of a projector, and on this condition a novel systematic method is proposed for projector calibration. In this paper 3ds MAX and Matlab are applied to the computer simulation study. The main research contents are as follows:1. According to basic principle on 3D measurement system based on structured light, in the quite typical in at present and application quite widespread trigonometry mathematical model foundation, considered the camera lens distortion and the image Skew deformation influence, made the improvement to the model.2. In above camera mathematical model foundation, projector regarding as the reversion camera model, obtains the spatial point and the projecting apparatus DMD correspondence relations using the phase-shift method, then improved camera and projector calibration method in two steps and in the plane calibration method.3. Establishes the structure light 3D survey simulation system in 3ds MAX, and calibrated in the simulation system to known intrinsic and extrinsic parameters of camera and projector. After using the calibrated simulation system carried on the object 3D survey and the restructuring experiments.4. Using CCD camera and DLP projector established measurement system, and completed to the camera and the projector calibration, after the use calibrated system carried on the survey and the restructuring experiments.The experiment results indicated, the simulation calibration parameters relative error is smaller than 0.25%; The simulation system measuring error is smaller than 0.2mm; Physics experiment focal length calibration error is less than 0.1 mm; imaging center calibration error is less than 0.5 pixels; The actual system plane measurement error is less than 0.4mm; obtained the good visual effect to complex 3D superficial restructuring.