Survey of Process Planning Techniques for Layered Manufacturing

This paper focuses on process planning for LM and provides a survey of techniques developed to date. Process planning is performed to generate the tool paths and process parameters for an object that is to be built by a particular LM process. The steps required are: part orientation, support structure generation, slicing, path planning, and process parameter selection. STL files, solid models, and image and reverse engineering data are all considered as possible input to the process planning system. The techniques reviewed can be used for a variety of LM systems.

Efficient Algorithm for Automatic Support Structure Generation in Layered Manufacturing

Stereolithography is a process used to rapidly produce polymer components directly from a computer representation of a part. There are several considerations to be made for the efficient use of the process. Especially, the necessity of support structures, which prevent the part from warping, sagging, or parachuting and toppling as the elevator moves up and down in the resin, is one concern. After solidification, the support structures must be removed in the end. Thus the more the support structures, the more it increases the finishing operations. Especially for a complicated part, the removal operations may be difficult, take so much time, and even reduce the accuracy of the product. It is, therefore, important to efficiently generate the support structure for each part geometry. This paper proposes a algorithm to automatically generate the support structure focused on accuracy, efficiency, convenience, and generation speed. Besides, we can exactly determine an optimal build-up direction for the minimum volume of support structures.