Coordinate Measuring 2.0 Research And Development, Data Pre-processing System

Generally, in the CAD technology of reverse engineering, data come from the three coordinates measuring machine (CMM) are the source of original information, and the modeling and the manufacture of the products are based on them. However, CMM data can not be used directly in the modeling because of the orientation, dimension, obstruction handling, superficial physical property and distortion of the products be measured. So, pre-handling of the CMM data is one of the most important steps in reverse engineering.The present popular CAD systems can deal with CMM data to some extent, such as: delete noisy points, rebuild symmetrical benchmark, data combination. But, since the softwares which have such functions are not be developed for reverse engineering specially, they cannot meet with the needs of reverse modeling nicely. The main reasons lie as: first, lack of special module and is hard to operate; second, module functions are incomplete and its capabilities are limited; third, rely on workers too much, cannot ensure the precisions.So, we have developed a special pre-handling system for CMM data based on deep study. Follows are the main functions of our system:(1) Data Transform. Implement bilateral data exchange between several kinds of CMM and CAD/CAM systems.(2) Data Combination. Combinate the data which are in the different coordinate systems into one coordinate system.(3) Data Processing. Automatic find the symmetrical benchmarks of the products; Software rectification of the distortions of the products.(4) Data Saving. At the data saving step, the scan data also can be saved after being processed in line with the process of outline data.Practice shows that the efficiency and the quality of pre-handling of CMM data are improved obviously by using our system.