Research On Denture Manufacturing Numerical Control System Based On PMAC

Dental defects are common and frequently-occurring diseases, people often use denture to repair them. Traditional denture manufacture process consists of contouring, embedding wax patterns, vacuum casting and porcelain veneering; all these work must be done manually, as a result, the manufacture process is time-consuming and depends on worker’s proficiency. By using CAD/CAM technology to manufacture denture can strongly shorten the course of the treatment, both improve the work efficiency and repair quality. In this way, CAD/CAM technology has deep affection on removable prosthodontics.According to the feature of prosthodontics, dental CAD/CAM technology mainly consists of three parts:data acquisition, data processing and CNC manufacture technology. This project establishes the numerical control system of the dental CAD/CAM system and reform the3D dental surface from scattered data cloud.Numerical control system uses PMAC(Programmable Multi-Axis Controller), which is the product of American Delta Tau Company, as the NC device and uses IPC(Industrial Personal Computer) as the upper computer. The project bases on VC++6.0develop environment and uses a dynamic link library which is called PComm32to complete the communication between NC device and upper computer, in this way, it establishes a "PMAC embedded in IPC pattern Open Architecture CNC System". Numerical control system mainly consists of two parts:hardware and software, in which hardware platform mainly includes servo control system, electrical control system and electrical component layout. Software development include NC device software and upper computer software, we write motion control programs and PLC programs in NC device, in which these programs can be executed in real time, in the same time, we develop multi-axis debugging interface and motion monitoring interface in upper computer, in which users can easily monitor and debug the numerical control system. This article uses multi-level uniform bicubic B-spline algorithm to computes a C2-continuous surface through a set of irregularly spaced points. Experimental results demonstrate that high-fidelity reconstruction is possible from a selected set of sparse and irregular scattered data cloud.Numerical control system is a very important part of dental CAD/CAM system. It is of significance to develop an Open Architecture CNC System which both has high reliability and superior cost-effective.