Selection of a Data Exchange Format for Industry 4.0 Manufacturing Systems Ricardo Silva Peres1, Mafalda Parreira-Rocha1, Andre Dionisio Rocha1, Jose´ Barbosa2, Paulo Leitao˜ 2, and Jose´ Barata1 1CTS - UNINOVA, Faculdade de Cienciasˆ e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal, Email: fricardo.peres, mafalda.rocha, andre.rocha, [email protected] 2Polytechnic Institute of Braganc¸a, Portugal, Email: fjbarbosa, [email protected] Abstract—With the emergence of the Industry 4.0 concept, or standard interfaces and common semantics as key enablers of the fourth industrial revolution, the industry is bearing witness interoperability within project itself. to the appearance of more and more complex systems, often requiring the integration of various new heterogeneous, modular A. The PERFoRM Project and intelligent elements with pre-existing legacy devices. This challenge of interoperability is one of the main concerns taken The PERFoRM project is aligned with the Industry 4.0 into account when designing such systems-of-systems, commonly vision aiming the conceptual transformation of existing indus- requiring the use of standard interfaces to ensure this seamless trial production systems towards plug and produce production integration. To aid in tackling this challenge, a common format systems to achieve flexible manufacturing environments based for data exchange should be adopted. Thus, a study to select the foundations for the development of such a format is hereby on rapid and seamless reconfiguration of machinery and robots presented, taking into account the specific needs of four different as response to operational or business events. An important use cases representing varied key European industry sectors. assumption, as an innovation action, is not to create a new system architecture from scratch but instead to use the best I. INTRODUCTION results of successful previous R&D projects, like SOCRADES Technological developments have always been the corner- [4], IMC-AESOP [5], GRACE [6], IDEAS [7] and PRIME [8]. stone of what is normally referred to as an ”Industrial Revolu- This consideration will help the industry adoption of these new tion”, be it the mechanization, electrification or digitalization and emergent solutions. of production [1]. These disruptions consist essentially in large The PERFoRM achievements will be validated in four paradigms shifts originating from the need to fulfil both varied different industrial use cases covering different industrial au- and varying market requirements. tomation systems, ranging from home appliances to aerospace Coincidentally, over the last few years there has been an and from green mobility to large compressor production. This increase in the demand for highly customised products, making diversity of use cases introduces different requirements in a clear change from a seller’s to a buyer’s market. This trend terms of data models, touching, amongst others, maintenance, of increasingly up-to-date, individualised products (i.e. batch logistics, sensorial data, Manufacturing Execution Systems size one) translates into a need for manufacturers to become (MES) and Enterprise Resource Planning (ERP) data. more and more agile in order to deal with these rapid market changes, as well as flexible [2], particularly in production, B. Standard Interfaces for Interoperability due to the sheer amount of variants and variables. These An important key issue to ensure the interoperability in real factors are once again fuelling such a revolution, albeit a industrial environments, interconnecting heterogeneous legacy planned one, which is being referred to as ”Industry 4.0”. hardware devices, e.g., robots and Programmable Logic Con- This vision revolves around six core design principles [3], trollers (PLCs), and software applications, e.g., Supervisory namely advocating decentralization, virtualization, real-time Control and Data Acquisition (SCADA), MES and databases, capability, service orientation, modularity and of particular is to adopt standard interfaces. These aim to define the inter- interest for the topic of data representation and harmonization, face between devices and applications in a unique, standard the principle of interoperability. and transparent manner, ensuring the transparent pluggability This movement has spiked the interest of researchers world- of these heterogeneous devices. For this purpose, a standard wide and in particular in Europe, given its German origins, data representation should be adopted by the interface that which has resulted in the emergence of several European should also define the list of services provided by it, and the funded projects focused on this topic. Such is the case of semantics data model handled by each service. In this defini- the H2020 Production harmonized Reconfiguration of Flexible tion, and particularly for industrial automation, several ISA 95 Robots and Machinery (PERFoRM), which will be introduced layers addressing different data scope and requirements should in I-A and to which this technology assessment pertains. be considered, namely the machinery level covering mainly L1 Afterwards, Subsection I-B contextualizes the importance of (automation control) and L2 (supervisory control) layers, and 978-1-5090-3474-1/16/$31.00 ©2016 IEEE 5723 the backbone level covering the L3 (manufacturing operations these standards have been developed. The list presented below management) and L4 (business planning and logistics) layers. has been selected from the pool of technologies currently The achievement of the complete interoperability and plugga- available and documented in the literature which stand out as bility requires to complement the use of standard interfaces potentially fulfilling some or most of PERFoRM’s semantic with adapters to transform the legacy data representation into needs. the native standard interface data representation. • IEC 61512 BatchML (T1) - An XML implementation The remainder of this paper is organised as follows: Section of the ANSI/ISA-88 Batch Control family of standards. II introduces some of the main standards (and their imple- It offers a variety of XML schemas written in XML mentations) for data representation and modelling, along with Schema Language (XSD) that implement the ISA-88 their coverage of relevant concepts which act as differentiation specifications. criteria. Subsequently, Section III describes the methodology • IEC 62264 B2MML (T2) - Implements the ANSI/ISA- to be used for the selection of the aforementioned technolo- 95 family of standards for Enterprise-Control system gies, detailing each step of the decision process. Consequently, integration via XML schemas written in XSD. The latest Section IV entails the application of this methodology for versions of BatchML’s schemas were integrated into the the technology assessment, along with a brief discussion of B2MML namespace, now using the B2MML common the results. Finally, Section V proposes a few underlining and extension files. Despite this fact, for the purpose of conclusions, followed by some acknowledgements. this study both implementations will still be considered II. TECHNOLOGIES FOR DATA REPRESENTATION AND separately. MODELLING • ISO 15926 XMplant (T3) - Provides access to process One of the main challenges presented for Industry 4.0 is plant information in a neutral form, following the ISO the representation and seamless exchange of data originating 15926 specifications, supporting structure, attributes and from heterogeneous elements, often from very different, albeit geometry of schematics and 3D models; related, action levels. A clear example using the ANSI/ISA- • IEC 62424 CAEX (T4) - Computer Aided Engineering 95 standard [9] terminology would be the harmonization of Exchange (CAEX) [19] is an object-oriented, neutral, data pertaining to the Enterprise Resource Planning (ERP), XML-based data format that allows the description of to the Manufacturing Execution System’s (MES) layer and to object information, such as the hierarchical structure of Supervisory Control And Data Acquisition (SCADA) systems. a plant or series of components. Its scope spans across Coincidentally, the subject of standardization is consistently a wide variety of static object types, such as plant, indicated by the industry as one of the major obstacles for the document and product topologies as well as petri nets; industrial acceptance of disruptive technologies [10]. In fact, • IEC 62714 AutomationML (T5) - AutomationML is several European funded projects have already made some an XML-based data format that builds upon other well efforts to push towards this goal. Some examples include established, open standards spanning several engineering the BatMAS [11] and FP7 PRIME [12] projects. The latter areas, aiming at interconnecting them. More specifically, highlights the importance of a common semantic language CAEX serves as the basis of hierarchical plant structures, and data representation in order for proper interoperability while COLLADA and PLCopen XML are the founda- and pluggability to be achieved, due to the plethora of tions for geometry/kinematics and control applications, heterogeneous entities involved in these intelligent, complex respectively [20]; manufacturing systems [13]. • OPC UA’s Data Model (T6) - OPC UA defines a very In fact, over the last few years several industrial standards generic object Data Model (DM) supporting relationships have emerged, each providing a set of semantic definitions between objects (references) and multiple inheritance.