Research An Optimization Algorithm For Tool Path Generation Of Dental Restoration Based On Feature

Discrete surface and CNC machining technology has been the hot topics in the study of domesticand foreign scholars, and is widely used in some fields, such as aviation, spaceflight, shipbuilding,automobile, biomedical field and so on. This paper study an optimization algorithm for CNCmachining tool path based on dental restoration features, which is sustatined by the national scienceand technology support projects and based on the background of the system development for dentalCAD/CAM. The main work and results as follows:(1) In order to solve the problem of frequent retraction of direction parallel tool path innon-convex machining of dental restoration, a generation algorithm of guide lines planning ontwo-dimension plane is presented. First of all, topology relationship between the boundary ofmachining region and intersections should be established, and then the intersections and points in theboundary should be linked to form continuous guide lines with less retraction, according tocorresponding relationship. The tool retraction of the resulting tool path generated by the proposedalgorithm is equal to number of guide lines. It can significantly reduce the frequency of tool retractionand improve the processing efficiency.(2) In order to solve the problems of frequent machine vibration and large overcut in theprocessing, this paper proposes a connection optimization algorithm for tool path and the modeloptimization algorithm based on accuracy. The transition space of three circular arc at the connectionmakes smooth transition in order to reduce the vibration of the machine, which can influence thequality of dental restoration. The approximate intersection on the contours of the teeth is calculated byfinding the end and the first cutter location points, which retains more characteristics. It cansignificantly reduce the amount of the over-cutting areas.(3) This paper develops the translation module of NC file based on machine translation, whichcan fully guarantee the numerical control operation in conformity with NC program. To verify thecorrectness of the tool path calculated by this paper, virtual machine of the special machine for oralrestoration is established by using VERICUT, which realizes double-sided process simulation of toolpath.