Volume decomposition of CAD models for rapid prototyping technology

Purpose - This paper reports on the work done to decompose a large sized solid model into smaller solid components for rapid prototyping technology. The target geometric domain of the solid model includes quadrics and free form surfaces. Design/methodology/approach - The decomposition criteria are based on the manufacturability of the model against a user-defined manufacturing chamber size and the maintenance of geometrical information of the model. In the proposed algorithm, two types of manufacturing chamber are considered: cylindrical shape and rectangular shape. These two types of chamber shape are commonly implemented in rapid prototyping machines. Findings - The proposed method uses a combination of the regular decomposition (RD)-method and irregular decomposition (ID)-method to split a non-producible solid model into smaller producible subparts. In the ID-method, the producible feature group decomposition (PFGD)-method focuses on the decomposition by recognising producible feature groups. In the decomposition process, less additional geometrical and topological information are created. The RD-method focuses on the splitting of non-producible sub-parts, which cannot be further decomposed by the PFGD-method. Different types of regular split tool surface are studied. Originality/value - Combination of the RD-method and the ID-method makes up the proposed volume decomposition process. The user can also define the sequence and priority of using these methods manually to achieve different decomposition patterns. The proposed idea is also applicable to other decomposition algorithm. Some implementation details and the corresponding problems of the proposed methods are also discussed.