An intelligent NC program processor for CNC system of machine tool

Abstract

NC program interpreting is one of the most important tasks of CNC in machine tool system. The existing CNC systems only support vendor-specific NC program input, which restrict the applying of other similar functional NC programs with different program format. Especially for those users owning several machine tools with different CNC from the same provider, the diversity of NC programs dramatically increases their cost and time on operator training and machine tool maintenance. In order to deal with the variety of NC program, an intelligent NC program processor (NCPP) is proposed in this paper. The proposed NCPP has a novel structure with separated NC specification dictionary and processing engine, which ease the CNC system to adapt to a new NC program specification by only updating the NC specification dictionary (NCSD). This paper explains the NC specification dictionary structure by using EBNF representation, which is further implemented in TCL, an embedded script language tool. Meanwhile, the unchanged processing engine has been designed from a compiler's point of view to process the data dictionary. A NCPP prototype is built to evaluate the proposed design. Case study shows that the proposed NCPP handles different NC program inputs successfully.

A meta-model of computer numerical controlled part programming languages

“…Researchers (Liu et al 2007;Schroeder and Hoffmann 2006) have tried to translate part programs and reuse them on different machines. The disadvantage of these solutions is that they only focuse on interoperability between CNC machines, not between the CNC machine and the CAx chain.…”

“…In fact, there is such a neutral representation developed by NIST (Proctor et al 1997) called Canonical Machining Commands to represent various programming dialects. The aim of the canonical commands is to represent RS274 (US equivalent of ISO 6983) codes to realise one-to-one correspondences with commands employed by commercial motion control boards (Liu et al 2007;Guo et al 2011). However, this model is designed for the RS274 language dialects and it embraces more specific and low-level data.…”

“…A file containing G&M codes would comprise many lines of text that would be interpreted as moving instructions for the servomechanisms connected to various axes of the machines (Smid 2003). With the wide use of G&M codes, it became the de-facto standard for CNC programming and then was formalised as RS-274D (USA), ISO6983 (ISO) and DIN66025 (Europe) (Liu et al 2007).…”

Research on the data hungry problem in CNC system based on the architecture of Real-time multitask

“…From the current development trend of high-performance CNC system in the world, the main focuses of their research are: open CNC system architecture [1] [2]; high-speed and high precision technology [3]; intelligence [4], networked CNC system. With the continuous development of highperformance CNC system, in order to avoid that the NC-code interpretation and data transmission speed in CNC system can not keep up with the high feed rate, it must deal with the corresponding NC-code faster and send the decoding data information to the next level module opportunely when the system is running on high speed and high precision processing.…”

Open architecture of CNC system research based on CAD graph-driven technology

“…Li [2] studied the automatic NC programming technology based on the graphic feature principle to realize the integration of CAD/ CAM system. Liu et al [3] researched the application of an intelligent NC program processor for CNC system of machine tool. Kovacic and Brenzocnik [4] proposed a concept for programming of CNC machines based on genetic algorithms on the basis of CAD models of manufacturing environment.…”