On the futuristic machine control in a STEP-compliant manufacturing scenario

STEP-NC (ISO 14649) provides a new data interface for computer numerical control (CNC) machine tools. However, replacing the current ISO 6983 with STEP-NC is not only a matter of change in NC programming language but it also has a far-reaching and profound effect on the future CNCs and even on manufacturing systems. The CNCs are destined to evolve from pure controllers into integrated systems with both decision-making and control abilities. In this paper, strategies for implementing the STEP-compliant CNC systems are discussed and a framework for the autonomous STEP-NC controller is proposed. The controller is organized into two agents: the planning agent and the machining agent. This paper also provides a general discussion on issues about the part program interpretation, the on-line process planning. In order to support dynamic planning as well as meet the real-time requirements in NC machining, it is proposed to solve the on-line planning issues in two stages, i.e. the shop-floor planning and the real-time planning. It is also proposed to extend the feature-based algorithm to the interpolation stage.