Research On The Key Technology Of The Vision Joint-type CMM

Reverse engineering as a new design method do a lot of things in absorption domestic and international advanced technique, shorten the product's development period and lower the production's cost. In reverse engineering, the vision joint-type coordinate measuring machines (CMM) put non-contact methods and tactile methods together perfectly, bring a new product to design, manufacturing and three dims measure mode. This paper based on the perfectly commercializing 3-D reverse engineering equipments HRE-I, HRE-II 3-D lasers scanning measure system, study the key technology in the vision joint-type CMM such as how to set up the joint-point mold, 3-D laser scanners work mode etc. Tactile methods are famous for its high accuracy in reverse engineering, On the basis of setting up mathematics mode of the pose and movement equation of probe end; we get the function of the measure precision analysis and adjustment model of the joint-type CMM. Describe the factors that influence the precision and how to decrease the error in theory. Be preparing for assembling the joint-type CMM that satisfy the request of accuracy in the given design precision. Study the key technology in the joint-type CMM. 3-D laser scanner takes advantage of acquiring data large, measure quickly and high precision. Which make up of one CCD camera and a semiconductor liner laser. Different from the double-CCD camera measure system, it establishes the mathematic model by the laser projection plane and the image that get by the one CCD camera. This paper present the digital image processing that get the one-pixel width laser stripe image from the image got by the CCD camera such as filtering waves, threshold image segmentation algorithm, throw the 2-D laser stripe project to 3-D scatter dots. Under the design condition of displaying the dots while get by the system on time. This paper predigests the digital image processing and proves it is true by test. We must display the data that acquired by the vision joint-type CMM on time, first of all, save the data on HDD as the ASC format, then use the 3-D soft of OpenGL to dispose of the data, such as lighting and texture; in this paper innovative present the buffer pool technique in the compute operator to assure the data display on time.