Development of a feature-based open soft-CNC system

Modern computer numerical control (CNC) is intended to be more flexible, interoperable, adoptable, open, and intelligent. In realisation of such a CNC system, an ISO standard known as STEP for numeric control (STEP-NC) or ISO 14649 was developed in 2004 to alleviate a number of challenges associated with the widely used CNC standard (ISO 6983). Implementation of STEP-NC was initially carried out on some commercial CNC systems via an indirect STEP-NC programming approach. However, this approach failed to meet all the requirements of a modern CNC system, due to the translation of data from the high level to low level, which is vendor-specific and machine tool dependent, thus detrimental to the basic resource independent philosophy of STEP-NC. This paper presents a new generation of CNC systems, based on the Open Architecture Control (OAC) technology supported by STEP-NC data model to fundamentally solve these challenges. The developed system employs a new set of techniques for STEP-NC data interpretation, graphical verification, execution, monitoring, and report generation that supersede the exiting techniques in scope and capability. Using these techniques, the proposed system provides a flexible, intelligent, and adaptable manufacturing platform that can provide unprecedented levels of scalability and resource allocation agility in modern manufacturing enterprises. A prototype implementation of the proposed model is based on STEP-NC interpretation, 3D simulation, machine motion control, and live video monitoring with automatic document generation modules has been used to verify and validate the system in conjunction with industrially inspired test components.