Study Of The Interpolation Of The Tool Path In Fast Tool Servo Turning

Free-form surface optics can achieve special optical properties,includingimproving the utilization rate of optics, reducing the amount of the components in thesystem and cutting short the size of the system.It has been widely used in civil, militaryand aerospace and other fields, and has a broad prospect. However, due to the nonrotational symmetry of the freeform surface microstructure and high surface qualityrequirement of free-form surface optics, the traditional machining method can't meet theneeds of processing. A Fast Tool Servo (FTS) ultra-precision turning technologywhich is provided with the rapid tool carrier with high frequency response is applied onthis occasion. Its diamond tool can move rapidly along the Z axis during the machiningprocess with high accuracy. Therefore, FTS can effectively process non rotationalsymmetry microstructure surface.This paper mainly focus on the study of the generation of tool path and theinterpolation technology in fast tool servo turning.In this paper, we planed the tool pathby using the equal scallop height method and proposed a method of acceleration anddeceleration control in a real-time NURBS curve interpolation. The main contentincludes the following several aspects.Based on the characteristics of the processing of fast tool servo turning, we discretetool contact points by using the equal angle method in the circumferentialdirection.Through comparing several commonly used tool path planning methods toexplain the advantage of the equal scallop height method,and generate tool path by thismethod in an example of typical free-form surface.In this paper,we analysised the drawback of the traditional linear and arcinterpolation method in free-form surface machining and stated the necessity ofadopting curve interpolation. We studied the interpolation speed planning method,according to this study, we put forward a new kind of real-time acceleration anddeceleration control method which is deep into the acceleration level, so as toeffectively improve the dynamic performance in the process of machining, and ensurethe quality of machining. Finally, the method is verified by a real-time NURBSinterpolation which is designed in this paper. The work has been done in this paper canhelp with the further study of the processing of the ultra-precision turning method offree-form surface.