Stepwise volume decomposition for the modification of B-rep models

During product design, the modification of computer-aided design (CAD) models is frequently required. However, modifying a boundary representation (B-rep) model, which is a typical type of CAD model, is difficult and time consuming. To address this problem, we propose a method for modifying B-rep models. In the proposed method, a B-rep model is decomposed into simple volumes by stepwise volume decomposition. A pseudo feature tree called the composition tree is generated with the decomposed simple volumes. A user can modify the B-rep model by transforming or deleting constituents of the composition tree and then replaying the updated composition tree. To demonstrate the proposed method, a prototype system was implemented, and experiments with test cases are performed. Based on the experimental results, we verified that B-rep models could be easily modified using the proposed method.