Model support algorithm in powder based three dimensional printer

Generally, rapid prototype system, it bases on the operation principle to process layer by layer, and has several kinds of hardware already. The input of STL file format has become the de facto standard in rapid prototyping. With the application of complex material, the variety of product-type using RP technology will be dramatically extended and, no more, be limited in model production. However under the structure of 3D printing, large item production will be possible only if specific support were applied. This study proposes the hardware and software integrated method with the subject of the three-dimensional printing. The hardware utilizes ink-jet of general two-dimensional printer and combines with the traversing mechanism and the process controls and model material, and piles up in accordance with default layer thickness. As the supporting structure in STL-file format is generated through the concepts of the 3D-printing support generating method which is carried out by performing projection and displacement of selected triangular surfaces and then the generated 3D model is further constructed by Open GL and saved in STL-file format. As STL file is read, and then builds adjacency to store into the topology data structure. After the operation of direct slicing rule, hundreds of contours in each layer are obtained by using Visual C ++ programming language and OpenGL library to implement the algorithm above. It can confirm exactness that the software output and systematic feasibility of integrating the hardware through the result of system integration test on the 3D printer.