Design And Implementation Of The Tool Compensation In The CNC System Based On RS274/NGC

The tool compensation function in machine processing is the important module of CNC system. It includes the design of the tool path, the compensation of tool geometric parameters and the logic processing.The design and implementation of the tool compensation in the CNC system based on RS274/NGC language can provide convenient instructions, extend the scope of machine processing and it also relates to the accuracy of the system. On the basis of studing some related theoretics, this dissertation solve the following problems:1. Using the representation of the directed geometric elements, here are lines and circles, to solve the problems of the tool compensation of CNC system. This dissertation gives the storage formats of the directed line and circle and uses them to describe the tool path. In order to design and implement tool compensation expediently, it also gives the computing formulae of intersection between two directed geometric elements, such as two lines, line and circler and two circles.2. Designing and implementing the tool radius compensation in CNC system. The tool radius compensation capabilities of the system enable the programmer to specify that a tool should travel to the right or left of an open or closed contour in the composed plane of arcs and straight line segments. This dissertation analyses the common tool radius compensation algorithms of the CNC system and indicates the shortcomings of the algorithms, finally it improves them.3. Studing tool length compensation and tool offset algorithms. When discussing tool length compensation, according to whether considering tool radius compensation or not, this dissertation analyses the two situation in detail. And then unified formula is given. It also discusses the resemblance and difference between tool offset and tool radius compensation.