| Optical measurement have been widely used in reverse engineering, product quality control and testing, biology, medical engineering, heritage repair and other fields,because of its high efficiency, high precision, non-contact, large field of view, visualization, intelligence which traditional measurement can not match.Since light measurement only samples the surface of an object which is visible from a given viewpoint, in order to measurement the entire object, it is necessary to merge the multi-view cloud data. At present, the efficiency of the multi-view cloud data merging is low. In this paper, a new 2-Axis rotary three-dimensional measuring system based on structured light was proposed. And the multi-view cloud data merging was completed automatically, while using viewpoint planning strategy for the measurement process to improve measuring efficiency.Firstly, the applications and development of the optical measurement were described. The measurement method based on Gray Code, Phase Shift and their combination was described. The two major questions in this paper were presented which were 2-axis turntable calibration and view planning. And the current status of the research related to these two questions was analyzed.Second, the experimental platform of a 2-axis turntable structured light three-dimensional measuring system was developed and the whole control system was completed. The experimental platform includes projection shooting module and 2-aixs turntable module. The task of control system development includes control program selection, control process design, PLC coding and communications development. PLC was selected to control the entire system precisely and stably. And MSComm was choosed to complete the serial communication between PLC and PC.Thirdly, a new method to calibrate the axes of the turntable automatically was presented based on the measurement data in the structured light measurement system. Two balls were mounted on the turntable by a given mode. The two balls rotated around the swing axis and were measured at different angles. Each ball's data was acquired and used to calculate its center. Each ball's center could define a circle. The two circles'centers defined the swing axis. The rolling axis at the origin position could be decided in the same way. Then the rolling axis at any position could be calculated easily. So the multi-view cloud data could be integrated automatically. Experiments show that this method is simple, efficient and could be used in other measuring system with a turntable. The experiment of calibration accuracy assessment was presented.Fourthly, view planning for an unknown object in the 2-axis turntable structured light three-dimensional measuring system was completed. Pre-scan view planning algorithm was presented and most cloud data of the object was aquired quickly. And then final-scan view planning algorithm based on estimation the location of cloud hole was presented.Finally, a 2-axis turntable structured light 3D scanner was developed. And the engineering applications such as tooth model measurement, nose model measurement and rabbit model measurement were given to verify the property of the scanner and satisfactory result was achieved.
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