SYSTEM ENGINEERING FRAMEWORK FOR MANUFACTURING SYSTEMS

Transcription

1 SYSTEM ENGINEERING FRAMEWORK FOR MANUFACTURING SYSTEMS M.Messaadia 1,2, M. Djeghaba 2, AEK. Sahraoui 1,3 (1) LAAS-CNRS, 7 Av colonel Roch 31077Toulouse, cedex04 (2) LASA-Université Badji mokhtar Annaba (3) IUT-B Université Toulouse le Mirail {sahraoui, messaadia}@laas.fr, djeghaba_mes@yahoo.com ABSTRACT The paper deals with the developing of systems engineering framework for manufacturing systems. In order to attain such objective, we propose an approach on deploying systems engineering processes and to map the structural view of systems engineering to a manufacturing systems. A linkage between the final product, the manufactured product, and the product systems, and the manufacturing systems, is carried out through PLM processes. For the paper, only a partial set of processes will be discussed. The approach makes use of the s engineering standard. Keywords: processes, manufacturing systems, systems engineering, deployment 1. INTRODUCTION AND PROBLEM ATATEMENT 1.1. Introduction The purpose of the requirement process is to develop requirements to satisfy needs, analyze the system, to derive a more detailed and precise set of requirements and to manage those requirements throughout the development cycle. The SE framework may vary either with respect to the system developed or/also depending of company policy; for such principle we propose that any SE framework must be defined; we resume our approach for such item as illustrated by the following figure 1.2. Problem statement The s Engineering (SE) methodology was conceived in the 1960 s to solve issues resulting from the increasing complexity of products developed in the space industry. At the present the industry which adapting and introducing SE, which describes an example of a SE integrated development framework. In this case, focusing on components development, SE has been chosen to remedy the lacunas of the current Concurrent Engineering environment within the company. Our approach is similar, focusing the manufacturing systems engineering. The SE applied to the new product development, but design was always neglected: The earlier practices on co-ordination between products and related manufacturing systems engineering have to evolve, in order to build on the previous efforts aiming to improve the product development. 2. MANUFACTURING SYSTEMS DESIGN AND SYSTEMS ENGINEERING system is a system. Designing a manufacturing is based on high level requirements as business and strategic requirements and also technical and systems requirements. This part is on the necessity for a novel approach for manufacturing design ; such approach as discussed in the remaining of the paper is highly based on systems engineering approaches in terms of processes, methods, tools and associated standards systems design requirements The vision for future manufacturing is that more and more organisations will have to adopt an agile mindset in managing relationships to find world-class customer and supplier partners. In this context, manufacturing businesses will have to make continuous reassessments of their core strengths and competencies. Companies will need to increase their focus on high-added-value products and technologies, yet at the same time broaden the total service spectrum within which these are brought to market. Such objectives are based on initial requirements that are linked to the type of processes and the flexibility of product to be manufactured. The aim is to set up a comprehensive consolidation of requirements related to the computational infrastructure. Requirements involve both functional specifications the system is expected to meet, as well as technological requirements. Technological requirements combined with a state of the art investigation will clarify which technological framework is best suited for the area of virtual manufacturing. State of the art technologies are going to be investigated and evaluated for their appropriateness, including agent technologies, workflow management systems, workflow specification languages and Web Services standards. The objective is to identify the benefits from adopting each technology studied and assess its effectiveness and relevance in the context of virtual manufacturing. The notion of a workflow, defined as a partially ordered sequence of tasks or activities, seems to fit nicely into the manufacturing process. The relevance of workflow

2 technology in the manufacturing area will be carefully considered, as well as the requirement for a workflow management system, and if deemed necessary, a framework for the execution of workflows will be developed The need for comprehensive approach for manufacturing design Such approach has been potential viewed as a way to map for a systems engineering approach 3. TAYLORING SYSTEMS ENGINEERING TO MANUFACTURING SYSTEMS 3.1. s engineering issues and concepts engineering is the application of scientific and engineering efforts to: -Transform an operational need into a description of system performance parameters and a system configuration through an iterative process of definition, synthesis, analysis, design, test, and evaluation. -Integrate reliability, maintainability, expandability, safety, survivability, human engineering and other factors into the total engineering effort to meet cost, schedule, supportability, and technical performance objectives. Engineering is an interdisciplinary approach that: Encompasses the scientific and engineering efforts related to the development, manufacturing, verification, deployment, operations, support, and disposal of systems products and processes. Develops needed user training, equipment, procedures, and data. Establishes and maintains configuration management of the system. Develops work breakdown structures and statements of work and provides information for management decision making. [10] Operational s Enabling Sets 2.3. The systems approach Figure1:ES approach for work packages A project to be carried out (named MANABLE) proposes the following approach, illustrated by the figure 2 Consists of Subsystem Subsystem s ion s Test s s s s s Fig3: product and enabling products structuring Figure2: systems In SE practice, it is made use for such difference; this is illustrated by the following (figure 3). In this paradigm system is decomposed initially into the end product (the operating system itself and the enabling product) all product that enable the production testing the deployment the support of the end product. The end product is at this time decomposed into subsystems, then each subsystems are decomposed into end product and enabling products and such refinement process will follow until we obtain elementary parts or component on the shelf (COTS); this is illustrated in (figure 4).

3 s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s s s s s ion s s s Project A User or Customer Desired Off-The-Shelf/Reuse s Build/Code s Building Block s Project B s Top-Layer Building Block Project B Technical management processes (three processes): these processes monitors the hall process ranging from the initial idea to build a system till the system delivering. [10] Acquisition and supply processes (two processes): these processes ensure the supply and acquisition (and are very close to logistics) design processes (two processes): these processes are on the elicitation and acquisition of requirements and their modelling, the definition of the solution and its logical design. realization processes (two processes): theses processes deal with implementation issues of system design and its use. Technical evaluation processes (four processes): theses processes deal with verification, validation and testing issues From SE to manufacturing: the framework is seen as a system via systems engineering view, we can see how to built system Figure4: s development structure We can see in the above figure (figure5) that some subsystems or and products are refined and some others are not refined as they exist all ready or available, for instance a PC computer is an end product that don t need to be refined since it is a cots system [7] es In SE good practice we have the following chain es Methods Tools The processes are best described by the following EIA standards figure (fig 5); there are thirteen processes covering the management issues, the supply/acquisition, design and requirement and verification validation processes.[9] S/system S/system Test s system Test s s s s s s s Planning Technical Management Assessment Control machines piloting ion s s s Plans, Directives & Status Acquisition & Supply Supply Acquisition Outcomes & Feedback Figure6: systems via SE 3.3. Linking the final product and enabling product Acquisition Request s Analysis Design Requirements Definition Solution Definition Technical Evaluation Requirements Validation Realization Implementation Transition to Use Requirements Designs s Verification s Validation Figure5: s Engineering es s These links enable planning and control of the engineering, through connections between systems and his manufacturing system. The manufacturing mission of the production system is the source of the connection. The date and the type of unvalued deliverable (information or product) can characterize this link. This link is refined when the engineering of the product or the manufacturing system is performed. As soon as the architectures are found, this link becomes a relation between defined systems and targeted deliverable exchange (still not valued) could be planned. [11] This link enables to optimize concretely the simultaneous engineering of product and related manufacturing systems. Exchange of valued information must occur between the

4 distinct technical tasks of each system. For instance, solutions of product design are taken as constraints for the manufacturing system requirements analysis. Solutions of manufacturing system design are taken as constraints for product Requirements Analysis. Concrete values must be considered here, because they induce feasibility and delay constraints. Essential contribution of enabling product design for the design of the end product is located in requirements engineering, as described in (EIA ). We can confirm this point of view: requirements analysis of the end product brings the source of information acquired from each enabling products. However, description of engineering, as architectural design of the enabling products was not clear in the standard (EIA ). For example consider the enabling product, the support system; we take specifically the maintenance system which is a part of the PLM in our taxonomy. The maintenance system monitors the product behaviour; some observation will be introduced to improve the reliability of the final product. Welding Welding (Y) (Y+1) Enabling 3.4. Relations between product and related manufacturing systems The processes for engineering a system are divided in four types. We have identified these four types by their ability to be applied distinctly or commonly to the s and/or the ion s: Technical and Agreement processes provide a generic description and can be distinctly applied to and ion s. Enterprise and Project processes bring coordination to the development of s and ion s needed to produce them. It is necessary to specify, among all the technical tasks realized by a development team, those belonging or contributing to and/or ion. Four of the nine Knowledge Areas in (PMBOK 2000) and the description of the Project Management Context are directly concerned with establishing a link between and ion s (manufacturing systems): Table1. Management Links between products and ion s Knowledge Area Link between products and production systems Project coordination (in Project Multi-Projects and Team Management Context) Coordination Through Enterprise Organization Project Integration Management Project Plan Project Time Management Activity Sequencing, Schedule and Control Project Communication Management Information Distribution Project Risk Management Risk Identification and Risk Quantification Actually SE offers the possibility to link the development of product and the development of enabling product in a unified framework. Hence the PLM offers such possibilities to materialise the linkage approach and the implementation approach. This work is a part of a project in deploying systems engineering; we address two issues; the first one is on maintenance and the second is on PLM which is the subject in this paper; our PLM is seen as sub product in the manufacturing structure and also as a tool for the linkage concept in systems engineering PLM: lifecycle management Fig 7: Bicycle frame manufacturing process We see in this example that only PLM ensures that the linkage is carried out between the enabling product and final product. Of course this can be applied only in the case of applying system engineering concept: distinction between final and enabling product. This can be illustrated by the (figure 7). More commonly referred to as PLM is emerging as the new method for industrial companies to better manage product development and in-service processes from beginning to end in the product cycle. lifecycle management (PLM) is a systematic, controlled method for managing and developing industrially manufactured products and related information. PLM offers management and control of the product ( and marketing) process and the order-delivery process, the control of product related data throughout the product life cycle, from the initial idea to the scrap yard. Almost without

5 exception, the PDM and PLM abbreviations also refer to a data system developed to manage product data [2]. In basic terms, product life cycle management involves the use of digital software to eliminate much of the costly trial and error that has plagued manufacturers since the industry took a step beyond the industrial revolution. Engineering And production (Engineering Change Request) which will be validated in order to establish the new bicycle (Y+1) with spring and its new manufacturing processes for a new framework addition of new part reprogramming of the machines... Requirement Initialisation Evaluation Realisation Welding (Y+1) Engineering Concept engineering And prototyping Info Sales And distribution Maintenance And repair validation P L M ES (Link) ECR ECO Create & Submit Inform Re Work - Accept alize Flow View E R P Requirement analysis And planning And recycling Figure 8: PLM information system context Welding (Y) PLM is seen as an information system; Lifecycle Management (PLM) systems control critical product information that must be shared with other enterprise 4. A CASE STUDY We adopt the linking approach for bicycle production and focus on PLM. The bicycle is the final product in SE taxonomy we try to apply such framework for a bicycle manufacturing project by enhancing PLM processes as an information system. The manufacturing is a part of the life cycle of the product which is cover by the PLM which contains the processes of manufacturing of the product. In our exemplar of the bicycle, the final end product (or system) would be the finished and complete bicycle. The end products of subsystems would include things like the wheels, the handlebars, and the frame. Each association between product and production systems can be managed as a connection between systems of each hierarchical system structure. In the example of the bicycle (Fig 9) we can see the process of manufacturing, which defines the manufacturing of all parts of the bike until the end product. When the new requirement is emitted which is for example add a spring in the frame of the bicycle this decision is managed by the PLM system. When the requirement is emitted it is transferred via the PLM towards the team from engineering which will take into account about the link established before between the bicycle and its system of manufacture (via ES) in order to define the impact of the addition of the spring on the bicycle and the system from manufacture which results in the change in the manufacturing processes. The PLM is given the responsibility to convey the emission of the ECR Figure 9: Bicycle The PLM will be also given the responsibility to safeguard and bring up to date the new product and its manufacturing process (Fig 10). Well Bicycle (Y) (Y) ion Chain Pedals PLM Chain Well Adding Bicycle (Y+1) Pedals Test (Y+1) Figure 10: Bicycle ion Test

6 5. CONCLUSION AND PERSPECTIVES A preliminary approach for PLM used as a tool for linking both the development of the product and the development of enabling products, has been presented. Such approach is highly based on a systems engineering framework for manufacturing systems. Perspectives forward are planned to refine the approach for maintenance process as enabling support product and the development of the tool. Such tool will be experimented for aeronautic applications. Annual International Symposium INCOSE 2003, INCOSE, Washington, DC, USA [12] PMBOK, "A Guide to the Project Management Body of Knowledge." PMBOK Guide, Project Management Institute, Newtown Square, Pennsylvania USA, AKNOWLEGEMENT The authors would like to acknowledge their colleagues Hani El-Jamal and Chad Coulin for their stimulating discussions on some aspects of the presented work and also the anonymous referees for the remarks for improvements on an earlier version of the work presented at conference on PLM. 6. REFERENCES [1] A.E.K.Sahraoui, D.M.Buede, A.P.Sages, Issues for systems engineering research, 14th Annual International Symposium INCOSE 2004, Toulouse (France), 11p, Juin 2004,. [2] A. Saaksvuori and A. Immonen lifecycle Management, er-verlag Berlin. Heidelberg [3] Geoff Hall The internet PDM and shared engineering the future of product realisation. [4] Mathias Bauer and al AgentSurvey: Assessing the state of the art of Industrial Applications Using Agent technology and AI Mathias Bauer and AI. [5] Rob. Bodington and al, Data Sharing in Virtual enterprise [6] H.X.G. Ming, W.F. Lu and C.F. Zhu, Technology Challenges for Lifecycle Management, STR/04/058/SP. [7] M.H. Jamal AEK. Sahraoui, Customising systems engineering concepts: case study on concurrent engineering Context. ESEC, European symposium on concurrent engineering systems, Toulouse April [8] Sergio. Terzi, Elements of Lifecycle Management Definitions, Open Issues and reference Models. PhD thesis politecnico di milano, Italia [9] EIA Standard processes for Engineering a 1998: EIA [10] M. Messaadia, M.H. Jamal, AEK. Sahraoui, s Engineering es Deployement for PLM. International Conference on Lifecycle Management (PLM'05), pp , Juillet [11] E. Lardeur, C. Auzet, of SE including s development: Practical Aspects. The 13th