Research On Generation Of Activity Model Oriented To Extrusion-type 3D Printer

As a new technology of rapid prototyping,3D printing is showing a trend of rapid development.3D printing is no longer the dedicated machines of designers and scientists. It has come out from the laboratory and factory, gradually to the ordinary consumers. The object of 3D printing is 3D model, now which can be downloaded from the web by ordinary consumers or general model library already exists. But those models are closed and the shape can not be changed. While in real life, there are many items such as the dolls of movement limbs, the lamp which can rotate. So how to generate model with movable joints is a problem that is worthy of study. It can add joints to the models by using the traditional 3D model software, which needs professional people to design joints for the specific model and adjust the various parameters. Thus efficient is low and is not easy to be accepted by the general person. On the other hand, because of low precision and fault tolerance of extrusion-type printer, if the parameters setting are not right,3D printing model with joints will not able to movable. So for the 3D printing requirement of the ordinary people, this thesis’s focus is that how to quickly generate a 3D model with an appropriate joint through a small amount of interaction, and which can be successfully printed as an activity model in the extrusion-type printer. With the help of interactive segmentation technology and the introduction of parametric design ideas, the research uses the method of solid modeling to generate the model with joints, in which mainly the work of following aspects has completed.(1) The design of common joint and the establishment of joint library. Based on investigating the joint type which appears frequently in the real life items, moveable joint models are designed by a method of solid modeling and be defined some associated parameters. At last, parametric joint library is constructed according to the degree of freedom of activity model.(2) Automatically adding the joints for the model. By specifying the position of the joint, after interactive segmenting the model which needs to add joints, the system selects the suitable joint according to division boundary and the moveable freedom which is selected by user, then it automatically calculates the parameters and generates the joint model which matches the segment model, at last the joint model is integrated seamlessly into the original model. (3) Model’s precision analysis oriented to extrusion-type printer. Aiming at the characteristics of extrusion-type printer, the parameters and attentions are summed up which impact the model’s precision. At last, a prototype system that includes segmentation, modeling and printing is constructed by integrating the generation algorithm of joint.