| The measurement of three dimensional (3-D) object's surface is important in machine vision and on-line 3D measuring in industry locale. Three-dimensional structured light vision measurement system has the advantages of non-contact, high speed, on-line and develop fast. Every kind of measurement system needs calibration. Basing on the study of internal and international system measurement development situation and calibration methods, we put forward a new calibration method. We move special filament in system two-dimensional measure section with standard orthogonal grid mode, so that the whole measure section is divided as standard space grid interval. We handle every grid node with sub-pixel orientation method and find out subsection linearity equation between every space grid interval by standard difference contrasting method. We calibrate system measure coordinates of every grid area according to the linearity equation. In the whole system measurement section, the same group grid can calibrate every sub-system. From the conversion of coordinates, the whole system is calibrated. The main jobs are as follows: 1. According to the system principle, we construct system mathematics model. At the same time we design the whole system parameters. 2. According the need of system calibration, we study the technique of sub-pixel orientation including method of centroid and grey centroid moment, and other correlation method. 3. We put forward the calibration method and list the detailed calibration process and data, then acquire system measurement results. The system calibration results show: this method is simple and reliability, speed is high, needs no iterative. Under the condition of no precision experiment device the system measurement errors are less than 0.2 mm within 100 mm depth measurement. The research fruits have important application values and economic benefit in on-line measurement of cable core, optical fibre products and stamping steel ribbon.
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