Design Of Coded Structured Light Panoramic Measurement Device

The coded structured light three dimensional measurement technology has theadvantage of non-contact, high sensitivity, high measurement accuracy, high degreeof automation and so on. So far it has been widely used in the area of aerospace,model manufacture, reverse engineering, medical and face recognition and otherfields.System calibration plays a significant role in the three dimensionalmeasurement system for completing the measurement task. Because the calibrationprocedure of plane model calibration method is simple and the operation is flexible,this paper will use this method to accomplish the calibration of the camera. Theprojector can be seen as the reverse camera, the projector can only project the images,rather than shooting images. Therefore, this paper proposed a projector calibrationmethod which used the orthogonal phase shift coding and plane model calibrationmethod to calculate the two dimensional coordinate in the projector’s image planeand accomplished the calibration of the projector.Due to the measurement range limitation of the coded structured light threedimensional measurement system, the system could only measure one part data ofthe measured object surface. To acquire the whole data of the surface of the object,the object needs to be measured many times through rotation and translation fromdifferent perspective, and putting the point cloud data into the same coordinate, it isalso called as the registration of the point cloud data. For the registration problem,this paper proposes a point cloud registration method based on the FASTRAKelectro-magnetic registration, and researches the registration principle andregistration process.Build the system measurement and registration experiment platform, calibratethe camera and projector, use the measurement system to measure the plane andcurved surface, and analyzing the measurement error. Measure the object from different perspective, and accomplish the registration experiment using theFASTRAK electro-magnetic motion tracking system. The experiment results showthat after calibration of the system the error of the measured object surface is smalland the measurement accuracy is meeting the requirements. The surface of the objectafter registration is smooth and real, the registration accuracy is high and the speed ofthe registration is fast.