An open architecture motion controller for CNC machine tools

In this paper, a motion controller for computerized numerical control (CNC) machining is developed in accordance with open modular architecture controllers (OMAC) agreement and industry standards. The motion controller is a software package running on personal computer. It is developed based on modular structure adopting hierarchic organization mode. After analysis of software and hardware structure of common CNC machine tools, the motion controller is divided into series of module units. Dynamical behaviors of the controller are described using hierarchic finite state machine (FSM). Reconfigurable controller is realized through setting customizable parameters, appointing rules in module units naming, designing communication interfaces between modules and prescribing format of configuration file. The open architecture motion controller developed has characteristics of user-oriented modules and reconfigurable software, compared with the traditional CNC system of close structure. Besides increasing the degree of reusability and openness, application of above-mentioned open architecture motion controller leads to significant decrease of development time and maintenance cost.