Reviewing of STEP-NC Standards Related to Manufacturing Industries

INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 9, ISSUE 04, APRIL 2020 ISSN 2277-8616 Reviewing Of STEP-NC Standards Related To Manufacturing Industries

Noor Hatem, Yusri Yusof, Aini Zuhra A.Kadir, Mohammed M.A

Abstract: Modern programming for computer numerical control (CNC) Machine tools, which is advancing as a replacement to G code, is STEP- NC (Standard for Product Model Data Exchange for Numerical Control). STEP-NC is a current model for computer numerical control. It gives rich information about CNC machine tools. This paper reviews a chain of STEP-NC standards related to manufacturing industries across the globe. The Standards for STEP NC and STEP ISO14649 and ISO10303 have been sophisticated to insert interoperability into manufacturing projects to meet the defy of reacting to production on request. This paper highlighted reviews of the research been performed by different countries and researchers for the last 20 years. The authors believed that STEP-NC is one enabler in the eventuality that will be reached. In the future, the feedback part and online control for the CNC system should be included to achieve a smart and global manufacturing system.

Index Terms: STEP-NC, G&M code, ISO 14649, ISO 10303, CNC, data models. ——————————  —————————— 1. INTRODCUTION several difficulties that hinder CNC technology’s development. Over the last 50 years, there has been a significant It should be noted that the ISO 6983 can be considered as a development in machine tools, from basic machines that had low-level international standard that refers to switching controllers without memory and were operated with punching commands and an axis motion control. Several CNC tape to the currently improved CNC multi-processor manufacturers have attempted to address this problem by workstations [1]. Such workstations can perform various merging the existing ISO 6983 standards with their standards functions such as versatile control, multi-axis control, mistaken if high-level command code. In addition, this design enabled payments as well as multi-process produce including pounding the CNC machine manufacturer to create a programming machine and joined plant/turn/laser. Such capacities have language that helped prevent interoperability between resulted in responsible programming becoming increasingly manufacture and design [3]. When discussing information complicated while also making it necessary in the productive models that can improve CAD/CAM information sharing, it is age to develop disconnected programming devices in terms of important to examine STEP-NC. To ensure that the data flow CAD/CAM that can verify NC code. Although machines and between CNC and CAM was seamless, a new standard called tools have fundamentally changed, there has been no ISO 14649, commonly referred to as STEP-Compliant significant change in the programming dialect that has G- Numerical Control or STEP-NC was introduced. This standard code.Moreover, the “how to make” refers to instructions enabled applications’ data integration to be seamless from concerning which path to move to and where and how. G-code design to manufacturing [4]. At present, ISO focuses on is a form of CNC programming and refers to the language that developing the STEP manufacturing environment that is implemented for controlling CNC machines. CNC encompasses STEP in STEP throughout, as well as STEP out programmers often use G-code for programming apart from [5]. STEP-NC intends to rectify ISO 6983’s limitations through CAM programming. G-code is quite commonly executed in a machining processes and not tool motion. For this, object- typical machine’s CNC controller. Presently, post-processors oriented and feature-oriented concepts concerning working are used to develop G-code naturally in the majority of steps are implemented that create a seamless connection in computer-aided design/CAM programming frameworks. CAx so that CNC becomes more portable, open, adaptable, Further, G-code is committed to enhancing the present interoperable, intelligent, and flexible. In particular, STEP-NC manufacturing technology. The program form that G-code uses ISO 10303’s existing data models to create seamless defines typically refers to ISO 6983, which specifies the control and smooth information exchange regarding CAx. Moreover, program’s format that is used for the machine’s numerical there are numerous information sets included in ISO 14649 controls (NC). On the other hand, ISO 6983 is also useful in such as “How-to-make” (process plan) and “What-to-make” various geometric designations as well as to communicate (geometry). with machines [2]. Although G-codes are used in all CNC machines for controlling their operations, there continue to be 2 OVERVIEW OF THE CURRENT DATA MODEL STEP-NC STANDARD AND STEP ———————————————— At present, two versions of STEP-NC, which are ISO 10303- 238 and ISO 14649, are being worked on by the Technical  Noor Hatem is currently pursuing Ph.D. degree program in Committee’s two sub- committees [6]. It can be said that ISO mechanical engineering, Universiti Tun Hussein Onn Malaysia, 10303-238 and ISO 14649 are the STEP-NC standard’s two Malaysia. E-mail: [email protected] and she is a lecturer in University of Basrah. distinct implementation methods. There is a high possibility  Yusri Yusof (Corresponding Author) is currently a professor in that the ISO 14649 standard will be implemented when the Universiti Tun Hussein Onn Malaysia, Malaysia. E-mail: shop floor provides precise information to the CAM systems. [email protected] On the other hand, STEP AP 238, which is included in the STE  Aini Zuhra A.Kadir is currently a lecturer in Universiti Teknologi standard, is better suited for the thorough integration of design Malaysia. E-mail: [email protected] and manufacturing. Moreover, STEP-NC can offer CNC  Mohammed M.A is currently a lecturer in University of Basrah. E-mail: [email protected] machine tools direct input involving product information, including features, geometry, tool path, and machining steps

[7]. Presently, G-codes have used for programming CNC capabilities of NC systems’ particular CAM Shop Floor machines, and thus, they can only explain the precise tool Programming (SFP). movements and not provide information concerning the processed part. Unlike G-codes, STEP-NC does not explain to the machine how to perform a task but tells it what to do. STEP-NC refers to a feature-oriented, as well as an object- oriented data model that offers unique possibilities for supporting standardized and high-level information from the design to manufacturing process [8]. STEP-NC’s development and use can aid the manufacturing field in several aspects, some of which are explored in this section, as highlighted in [6], [7], [9]–[13].

3 BENEFITS OF STEP-NC: i) In the present CAx, it is possible for the information to get lost in the process as the CAD to CAM data transfer may be incomplete. In such cases, the geometry fixes are done in Fig. 2: STEP-NC CAx data flow CAM and not communicated with CAD, thus resulting in the data flow to the post to be restricted. Using diverse standards iii) As STEP-NC is independent of vendor and specifies is also a reason for information loss, as depicted in Fig. 1. fixtures’ safety areas as included in the setup, it ensures the STEP NC resolves such problems by offering a structured machine tools’ complete safety as well as adaptability. and complete data model that is connected to technical and geometrical information. Further, it puts forth one standard for iv) STEP-NC uses XML (ISO 14649-28) information different systems’ data integration, and thus, there is no transfer for ensuring e-manufacturing or web-based information lost from the design to the manufacturing cycle, as manufacturing. STEP-NC has many other benefits over ISO illustrated in Fig. 2. 6983, some of them are listed in Table1 G-code programming Versus STEP-NC standard [14]–[20]. Table1: G-code programming Versus STEP-NC standard [14]– [20].

Table 1: Comparisons between 14649 and 10303 model [21].

Fig. 1: Current CAx data flow

The information flow in the present systems is uni-directional. As Fig. 1 shows, CAx does not have any information feedback. Moreover, it is almost impossible to make any exigency changes, considering the present CAx’s uni- directional data flow. Also, as STEP-NC model structure, as well as standard feature description, coincides with ISO 10303, it can maintain CAx’s bi-directional information, as presented in Fig. 2

ii) The present CNC machines have been working as Table 2 presents the first Reference Model ISO 14649 along per the ISO 6983 data interface model that has low-level with Interpreted Model (ISO 10303), with the AIM and ARM information, according to “how-to-make” instructions. STEP- models considered as the STEP-NC models’ two distinct NC standard, on the other hand, includes high-level execution frameworks. However, it is also appropriate to use information asper “how-to-make” and “whatto-make” ISO 14649 standard when the shop floor provides precise instructions that can aid facilities such as simulation, information to CAM frameworks, while STEP AP-238, included optimization, and inspection in CNC controller. It can thus be in the STEP standard, is more suited for assembling joining said that STEP-NC’s data elements can sufficiently describe and a complete outline. Moreover, while the AIM is entirely NC data that is task-oriented. agreeable to STEP, the ARM included data that is assumed

will program a CNC machine [21], [22]. (iv) The STEP-NC data model can be applied to other technologies, and CCs can be used to scale it for matching the 100 IJSTR©2020 www.ijstr.org INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 9, ISSUE 04, APRIL 2020 ISSN 2277-8616

Table 2: Comparisons between 14649 and 10303 model. strategies based on the implementation of STEP-NC on the CNC system, and these approaches can be categorized into several development levels in the future, as present in Table 3.

5 PREVIOUS RESEARCH RELATED TO INTERPRETED STEP-NC APPROACH Several efforts have been made from the late 1990s to use the STEP concept as a data interface between CNC and CAD/CAM. It is important to note that STEP-NC was developed following numerous research projects being conducted by educational institutions (universities) and companies across the world. To reduce decrease the time lag

between a product being conceptualized to it being produced, 4 IMPLEMENTATION STRATEGIES FOR STEP- there have been several studies on using information NC CONTROLLER technology in design, analysis, as well as manufacturing Using STEP-NC for CNC was continued from years of practice [33]. At a STEP meeting in 2007 in Ibusuki, Japan, a numerous previous studies. Of these studies, few important STEP-enabled on-machine inspection demonstration was projects were funded by institutes, companies, and industries conducted. This meeting was attended by various major including Intelligent Manufacturing System (IMS) STEP-NC industry companies such as NIST, Boeing, STEP Tools Inc., [23]), Rapid Acquisition of Manufactured Parts (RAMP), STEP and Airbus. At this meeting, an on-machine inspection was Manufacturing Suite (SMS), Implementation of the STEP-NC conducted on a workpiece shaped like a fish-head. Though and MT Connect Standards for Additive Manufacturing [24], this demonstration did not take into account measurement European Strategic Program on Research in Information points optimization and inspection path planning, it was the Technology (ESPRIT) STEP-[25] Super Model [21], Intelligent first time STEP-enabled on-machine inspection was physically Manufacture for STEP-NC Compliant Machining and demonstrated [34]. Moreover, a High-level Inspection Planning Inspection [21], Architecture and implementation of closed- (HIPP) system was also proposed to execute STEP-enabled loop machining system based on open STEP-NC controller inspection tasks. [20], and Rapid Prototyping Project Description in STEP-NC Model [26]. Different approaches have adopted different

Table 3: Researchers work related to enabled intelligent STEP-NC controller

As per particular countries, in Germany, the study focused on involved significantly Moreover, [35] and [36] explored the developing and using STEP-compliant CAPP/CAM systems as necessity of a new ISO 14649 machining schema particularly well as NC controllers. In the STEP-NC project in Europe, in terms of asymmetric rotational parts, and they devised a Siemens, which is the CNC system vendor, and two German system known as STEP-TM CAPP System as a practical institutes, ISW in Stuttgart and WZL (Laboratory for Machine solution for implementing the ISO 14649 data model regarding Tools and Production Engineering) RWTH in Aachen that were turn/mill machining. In addition, the STEP Compliant System

101 IJSTR©2020 www.ijstr.org INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 9, ISSUE 04, APRIL 2020 ISSN 2277-8616 for Turning Operations (SCSTO) is another software that was researchers. Fig. 3 presents their different projects and created in the UK. As suggested by the term, SCSTO was research that has been performed by different country and developed as per the STEP-NC Turning features [37] and was researchers, all which were presented through international created using the JDataStore database and JBuilder 2005. collaboration between government, academic research The cutting-tools database in SCSTO included milling as well agencies, and industry. as turning tools. In this process, first, a file is created, then integration is conducted, and test query and database developed [38]. A study on STEP-NC was also conducted in Spain by [39], focusing on STEP-NC hardware approach and not software development, Furthermore, in Italy, [40] developed a unique data structure called SKEM–STEP compliant Knowledge Engine for Manufacturing. [41] from France Institute Recherche Communications et Cybernetique Nantes (IRCCyN) being one of them. He merged two complementary manufacturing platforms, one from New Zealand Intelligent and Interoperable Manufacturing Platform (IIMP) and another from France STEP-NC Platform for Advanced and Intelligent Manufacturing (SPAIM) for enhancing the integration as well as supervision of the Fig. 3: Publication on step-NC at different countries machining systems that have STEP-NC standard, In addition, the US National Institute of Standards and Technology, expanded [42] and developed a Feature-Based Inspection and 6 CONCLUSION Control System (FBICS) concerning examining and machining mechanical parts. In the past few years, numerous studies in This paper analyzed a concept for the current process of China have focused on STEP-NC. In [43] and [44], a STEP- programming using the STEP -NC Standard. STEP-NC NC Controller framework having OMI as per the ISO 14649 currently a globally advanced industrial standard for data was suggested. Further, Martin Gizaw who is from Malaysia interchange in the process of output configuration and worked on a system for creating ISO 14649 code concerning manufacturing. The models AIM and ARM (ISO 10303 and feature-based process plans to mill and turn operations as per ISO 14649) have been improved to achieve the Improvement STEP-compliant environment. Thus, It can be noted that the of CNC technology in the Manufacturing organization. The United States, Germany, New Zealand, Australia, Japan, authors believed that STEP-NC Is one enabler in the Korea, and the United Kingdom are actively developing based eventuality that will be reached. In the future, the feedback on STEP NC software are Edge CAM, CAD-CAM CNC part and online control for the CNC system should be included modeling technology. Table 4 as shows a review of the to achieve a smart and global manufacturing system. research that has been performed by different countries and

Table 4: shows a summary of the research that has been performed by different countries and researchers

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