Kleanthis Thramboulidis

Kleanthis Thramboulidis, Danai C. Vachtsevanou, Ioanna Kontou

Today's customers are characterized by individual requirements that lead the manufacturing industry to increased product variety and volume reduction. Manufacturing systems and more specifically assembly systems (ASs) should allow quick adaptation of manufacturing assets so as to respond to the evolving market requirements that lead to mass customization. Meanwhile, the manufacturing era is changing due to the fourth industrial revolution, i.e., Industry 4.0, that will change the traditional manufacturing environment to an IoT-based one. In this context, this paper introduces the concept of cyber-physical microservice in the Manufacturing and the ASs domain and presents the Cyber-Physical microservice and IoT-based (CPuS-IoT) framework. The CPuS-IoT framework exploits the benefits of the microservice architectural style and the IoT technologies, but also utilizes the existing in this domain huge investment based on traditional technologies, to support the life cycle of evolvable ASs in the age of Industry 4.0. It provides a solid basis to capture domain knowledge that is used by a model-driven engineering (MDE) approach to semi-automate the development, evolution and operation of ASs, as well as, to establish a common vocabulary for assembly system experts and IoT ones. The CPuS-IoT approach and framework effectively combines MDE with IoT and the microservice architectural paradigm. A case study for the assembly of an everyday life product is adopted to demonstrate the approach even to non-experts of this domain.

Kleanthis Thramboulidis, Danai C. Vachtsevanou, Alexandros Solanos

Recent advances in ICT enable the evolution of the manufacturing industry to meet the new requirements of the society. Cyber-physical systems, Internet-of-Things (IoT), and Cloud computing, play a key role in the fourth industrial revolution known as Industry 4.0. The microservice architecture has evolved as an alternative to SOA and promises to address many of the challenges in software development. In this paper, we adopt the concept of microservice and describe a framework for manufacturing systems that has the cyber-physical microservice as the key construct. The manufacturing plant processes are defined as compositions of primitive cyber-physical microservices adopting either the orchestration or the choreography pattern. IoT technologies are used for system integration and model-driven engineering is utilized to semi-automate the development process for the industrial engineer, who is not familiar with microservices and IoT. Two case studies demonstrate the feasibility of the proposed approach.

Kleanthis Thramboulidis

In the paper by D. Regulin et al. (IEEE Trans. On Automation Science and Engineering, vol. 13, no. 4, 1422-1432, October 2016) authors claim that they present a meta-model for the modeling of the Automated Material Flow Module (aMFM) and a model-driven design approach for aMFMs. In this letter we comment on the presented meta-model and the proposed model-driven approach regarding their potential for exploitation. We present specific arguments and make cases that call the authors design decision into question.

Kleanthis Thramboulidis, Theodoros Foradis

IoT is considered as one of the key enabling technologies for the fourth industrial revolution, that is known as Industry 4.0. In this paper, we consider the mechatronic component as the lowest level in the system composition hierarchy that tightly integrates mechanics with the electronics and software required to convert the mechanics to intelligent (smart) object offering well defined services to its environment. For this mechatronic component to be integrated in the IoT-based industrial automation environment, a software layer is required on top of it to convert its conventional interface to an IoT compliant one. This layer, that we call IoTwrapper, transforms the conventional mechatronic component to an Industrial Automation Thing (IAT). The IAT is the key element of an IoT model specifically developed in the context of this work for the manufacturing domain. The model is compared to existing IoT models and its main differences are discussed. A model-to-model transformer is presented to automatically transform the legacy mechatronic component to an IAT ready to be integrated in the IoT-based industrial automation environment. The UML4IoT profile is used in the form of a Domain Specific Modeling Language to automate this transformation. A prototype implementation of an Industrial Automation Thing using C and the Contiki operating system demonstrates the effectiveness of the proposed approach.

Kleanthis Thramboulidis, Foivos Christoulakis

Internet of Things is changing the world. The manufacturing industry has already identified that the IoT brings great opportunities to retain its leading position in economy and society. However, the adoption of this new technology changes the development process of the manufacturing system and raises many challenges. In this paper the modern manufacturing system is considered as a composition of cyber-physical, cyber and human components and IoT is used as a glue for their integration as far as it regards their cyber interfaces. The key idea is a UML profile for the IoT with an alternative to apply the approach also at the source code level specification of the component in case that a UML design specification is not available. The proposed approach, namely UML4IoT, fully automates the generation process of the IoT-compliant layer that is required for the cyber-physical component to be integrated in the modern IoT manufacturing environment. A prototype implementation of the myLiqueur laboratory system has been developed to demonstrate the applicability and effectiveness of the UML4IoT approach.

Kleanthis Thramboulidis

In the paper by W. Dai et al. (IEEE Trans. On Industrial Informatics, vol. 11, no. 3, pp. 771-781, June 2015), a formal mapping between IEC 61499 and SOA is presented and a SOA-based execution environment architecture is described. In this letter, the proposed in the above paper mapping and the execution environment architecture are discussed and their potential for the exploitation is disputed.

Kleanthis Thramboulidis

In the paper by W. Dai et al. (IEEE Trans. On Industrial Informatics, vol. 11, no. 3, pp. 771-781, June 2015), a formal model is described for the application of SOA in the distributed automation domain in order to achieve flexible automation systems. A service-based execution environment architecture based on the IEC 61499 Function Block model is proposed and a case study is used to demonstrate dynamic reconfiguration. In this letter, a review of the literature related to the use of SOA in Industrial Automation Systems is given to set up a context for the discussion of the proposed in the above paper SOA IEC61499 formal model. The presented, in the above paper, formal model and execution environment architecture are commented towards a better understanding of the potentials for the exploitation of the SOA paradigm in the industrial automation domain.

Kleanthis Thramboulidis

Assembly systems constitute one of the most important fields in today industry. In this paper we propose an open distributed architecture for the engineering of evolvable flexible hybrid assembly systems. The proposed architecture is based on the model driven development paradigm. Models are used to represent structure and behavior and a domain specific engineering tool is defined to facilitate the assembly system engineer in the engineering process of the assembly system. Specific meta models are defined to capture domain knowledge to guide the engineer in the construction of the models required to construct the assembly system. This work is a specialization of our previous work that defined a SOA based framework for embedded industrial automation systems. It adapts and extends, in the assembly systems domain, the 3+1 SysML-view model architecture defined for the engineering of mechatronics Manufacturing systems. The proposed architecture can be used to develop a framework for evolvable flexible and reconfigurable assembly systems that would exploit the benefits the Cyber Physical paradigm utilizing web technologies, the IoT, the Cloud computing and Big Data.

Kleanthis Thramboulidis

Industrial automation systems (IASs) are commonly developed using the languages defined by the IEC 61131 standard and are executed on PLCs. In this paper, a system-based approach for the development of IASs is adopted. A framework is described to refine the UML model of the software part, which is extracted from the SysML system model, and get the implementation code. Two implementation alternatives are considered to exploit PLCs but also the recent deluge of embedded boards in the market. For PLC targets, the new version of IEC 61131 that supports Object-Orientation is adopted, while Java is used for embedded boards. The case study was developed as a lab exercise for teaching the various technologies that address challenges in the domain of cyber-physical systems where Internet of Things (IoT) would be the glue regarding their cyber interfaces.

Kleanthis Thramboulidis

In the paper by G. Barbieri et al. (Mechatronics (2014), http://dx.doi.org/10.1016/j.mechatronics. 2013.12.004), a design methodology, based on the W life cycle process model, is presented and SysML is proposed as a tool to support the whole development process. In this letter, we discuss the presented approach, we point out technical errors and raise additional issues that might help in making the proposed approach applicable.

Kleanthis Thramboulidis

Industrial automation systems (IASs) are traditionally developed using a sequential approach where the automation software, which is commonly based on the IEC 61131 languages, is developed when the design and in many cases the implementation of mechanical parts have been completed. However, it is claimed that this approach does not lead to the optimal system design and that the IEC 61131 does not meet new challenges in this domain. In this paper, a system engineering process based on the new version of IEC 61131, which supports Object Orientation, is presented. SysML and UML are utilized to introduce a higher layer of abstraction in the design space of IAS and Internet of Things (IoT) is considered as an enabling technology for the integration of Cyber and Cyber-physical components of the system, bringing into the industrial automation domain the benefits of these technologies.

Kleanthis Thramboulidis

IEC 61131 has been widely accepted in the industrial automation domain. However, it is claimed that the standard does not address today the new requirements of complex industrial systems, which include among others, portability, interoperability, increased reusability and distribution. To address these restrictions, IEC has initiated the task of developing IEC 61499, which is presented as a mature technology to enable intelligent automation in various domains. This standard was not accepted by industry even though it is highly promoted by the academic community. In this paper, a comparison between the two standards is presented. We argue that IEC 61499 has been promoted by academy based on unsubstantiated claims on its main features, i.e., reusability, portability, interoperability, event-driven execution. A number of misperceptions are presented and discussed. Based on this, it is claimed that IEC 61499 does not provide a solid framework for the next generation of industrial automation systems.