On The Digital Combination Forming Processes Of Three- Dimensional Resin Models

Models have been not only widely used in high-tech industry such as aerospace, automobile, shipbuilding, but also used in the field of architectural design, accommodation furniture, and cultural creativity. The traditional forming processes are of higher costs and longer cycle. The development of computer technology promotes the development of rapid prototyping technology which is based on digital information processing technology. As a new method of model-forming, rapid prototyping technology has achieved direct integration from design to manufacturing, but has some limitations such as limited available materials, forming size, prolonged forming time, etc. This paper propose two digital combination processes on the basis of rapid prototyping technology, in order to achieve digitization forming of resin models.This paper reviews the principles of forward engineering and reverse engineering, establishes 3D geometric sample models and makes data processing of the models. Taking the thumb model as an illustration, this paper explores different rapid prototyping processes such as SLA, DLP, FDM, SLS, PIRP, etc. The forming precision of these processes are compared, and the results show that, the error of DLP is small but with relative expensive photosensitive resin material; PIRP forming technology forming time is short; PIRP and SLS forming technology are suitable for the preparation of large-size models.This paper promotes two digital processes:One forming process is based on the silicone mold and digital technology, and it achieves the low-volume forming of simple geometry model, such as the Thumb models. The accuracy analysis shows that the average positive deviation is 0.876mm and the average negative deviation is -1.007mm. The other combination process is based on casting molding technology of polyurethane material. It implements digital forming of large and complex models, such as the impeller. The accuracy analysis shows that the average positive deviation is 1.175mm and the average negative deviation is -1.164mm.