Computer-aided mould design modification and tool path regeneration for product change

Abstract

Due to the product design changes, a mould design will need to be modified many times and the affected tool paths also must be regenerated for the entire part. It is difficult to modify the mould design and regenerate tool paths automatically and efficiently with the existing CAD/CAM systems. To solve this problem, this research developed a mould design modification and tool path regeneration system. A new mould design modification algorithm, which is also applicable for non-parametric parts, has been proposed. With this algorithm, a mould design can be modified automatically based on the mould machining status. Novel tool path regeneration algorithms that can efficiently identify and replace the affected CL-points have been developed to minimize the NC re-programming errors and reduce scraped parts. With these algorithms, the unaffected CL-points can be reused to machine the modified mould directly without recalculation. It is proven that the affected CL-points are enclosed by the CL-points that are corresponding to the interference-free boundary of the mould modification region. The algorithms and prototype have been demonstrated through a few industry case studies and are found to be applicable.