Manufacturing Systems in PLM Environments

Transcription

1 Concurrent Development of Products, Processes and Manufacturing Systems in PLM Environments a a,1 JanDuda and Janusz Pobożniak a Institute of Production Engineering, Cracow University of Technology Abstract. The paper presents the trends in the development of methods and systems for manufacturing and assembly process planning on the background of Concurrent Engineering strategies. The solutions for the functional integration of design/manufacturing and production preparation phases and the IT infrastructure including PDM systems for the storage of product structure data, design and manufacturing process documentation are presented. The concept and the example of integrated process and manufacturing system planning in PLM (Product Lifecycle Management) environment are presented. Keywords. Concurrent Engineering, design/manufacturing integration, PLM 1 Introduction In computer integrated development of products, processes and manufacturing systems, different methods are used to aid the engineers. The most important outcomes of the implementation of modern product development strategies are the shorter product start-up cycles and the faster completion of orders. The magnitude of benefits depends on the degree of information integration between the technical production preparation phase and the production planning activities. To speed-up the design and planning activities, the computer systems for product and manufacturing systems development featuring the growing degree of automation are widely used, while the information integration is achieved by using the integrated IT systems. The Digital Manufacturing portfolio comprises of multiple solution components such as process planning, process simulation and manufacturing process management solution framework for data management, change management, web enabled collaboration etc. So the challenge lies in identifying and integrating the areas to meet the objectives of Digital Manufacturing initiatives with PLM/ IT initiatives. The papers presents the methodological approach linking CE techniques with capabilities of nowadays manufacturing process management solutions. 1 Institute of Production Enigneering, Cracow University of Technology, Al. Jana Pawla II 37, Cracow, Poland, Tel: ; Fax: ; duda@mech.pk.edu.pl; J. Pokojski et al. (eds.), New World Situation: New Directions in Concurrent Engineering, DOI: / _5, Ó Springer-Verlag London Limited

2 38 J. Duda and J. Pobożniak 2 Trends in strategies and computer systems for concurrent product development According to the new development strategies, the product development focuses on: as much as possible parallel execution of all development related product life cycle phases, thus creating CE (Concurrent Engineering) environment. CE strategy assumes the development of resources and production facilities at the early product design phases to shorten the production start-up time. incorporation of the relations between business and engineering activities CEE (Cross Enterprise Engineering), securing also the access to the resources of cooperating enterprises. The parallel execution and the integration of products and processes starts on the early product development stages and covers suppliers, clients, as well as internal and external IT solutions. CEE means that product components, parts, assemblies, systems and functional sub-systems are designed and developed across the local business and engineering boundaries. Intranet and internet are here used as the means for the communications and the information exchange. Concurrent engineering is the computer integrated environment for design and manufacturing the common platform for computer aided systems used in the product development. The key condition for the effective concurrent engineering and cross enterprise engineering is the computer integrated environment of design and manufacturing the common platform for computer aided systems for the product development. Effectiveness of the CE and CEE strategies results from the better management of information in production process. The efficiency of activities depends on the provision of right information, to right places, for right peoples in the right time. PDM (Product Data Management) systems play the coordination role in the synchronization of the flow of information. PDM systems manage the data about the product services, product structure, its documentations and processes with the ability of processing data in the electronic form. PDM systems allow for modelling, storage and transformation of all data related to the product. Development of the integrated systems evolves toward the PLM (Product Lifecycle Management) solutions. PLM strategy increases the integration and automation of realized functions [1, 2, 4, 5, 6]. PLM environment includes the following applications for the product development: PPM ( Product and Portfolio Management), CAx ( Product Design), MPM ( Manufacturing Process Management), PDM ( Product Data Management). 3 Integrated process and systems development in PLM environment Features of modern development strategies indicate the need for product development phase integration.

3 Concurrent Development of Products, Processes and Manufacturing 39 Integration and parallel execution of activities were received through the separation of the conceptual design stages, allowing for the creation of the variant solutions. Variants are then evaluated in the view of the requirements of the next development phase [3]. The selected variant fulfilling the established criteria is next further developed in the detail design stage (Fig. 1). Figure 1. Parallel execution of product development phases

4 40 J. Duda and J. Pobożniak 3.1 Conceptual process planning stage The assembly process is created on the basis of the digital product model prepared with CATIA system. The process planning activities includes: the development of the product assembly structure separation of the assembly units (assemblies, subassemblies and parts), development of the assembly process plan including the basic parts for separated assembly units, methods and hierarchical order of assembly of these units to receive the design features of the product, mounting of subassemblies, assembles and parts prepared with Part Design module in Assembly Design module based on the developed assembly plan. The results of the above actions are necessary to make the assembleability analysis of the product and for iterative improvement of the design form in view of the assembly requirements. The product design resulting form the subsequent iterations and its assembly plan form the base for defining the graph of the assembly activities, representing the admissible variants of the execution of product assembly. 3.2 Conceptual production organization planning stage The conceptual manufacturing organization stage is used to select the appropriate form of the production organization, production pace, and the initial calculation of the number and type of functional subsystems. On this stage, also the type and organizational form of assembly system are selected. 3.3 Detailed process planning stage The selected type, organizational form of the assembly and the graphical product assembly plan verified with DMU Kinematics module of CATIA are the basis for the assembly process planning. The assembly process planning includes the selection of the operations and activities, selection of the assembly equipment, conceptual design of the assembly stations as well as the decisions on the concept and the selection or design of the transport system components. Based on the above process, the digital model of the assembly system and work places is created. The data required for the detailed production organization calculation and for the calculation of the duration of assembly activities are gathered from the components of the digital model of the system. The duration times of the assembly activities were determined using the MTM methods. 3.4 Detailed production organization planning stage The selected structure of the assembly process and the determined duration times of assembly activities covered by the operations are the base for the synchronization within the isolated assembly subsystem. For analysed production organization forms, for example production lines, these steps include the calculation of the number of stands and line balancing.

5 Concurrent Development of Products, Processes and Manufacturing 41 The activities for the selected organization forms (assembly stations) include ergonomic analysis. The outcome of the detailed production organization stage is the digital model of the manufacturing system linking all the components of the assembly system with assembly process plan stored in library and process schedule. The further test on simulation model are used to analyze and improve the system being developed. 4 Verification The verification was done with PLM solutions offered by Dassault Systemes. These solutions include the following systems (Fig. 2, 3): CAD/CAM CATIA for product, manufacturing process and resource design, PDM SMARTEAM and ENOWIA for the development process management, MPM DELMIA for process and manufacturing system design. 1. Design 2. Manage 3. Manufacture Figure 2. Areas covered by PLM Delmia solution The projects of gear reducer and car water pump were used to verify the presented concept and CATIA/DELMIA software deployed at Institute of Production Engineering.

6 42 J. Duda and J. Pobożniak Layout studies Time analysis (MTM) Process description and management Line Capacity Cost Estimation Production variants Studies Workplace Ergonomy Figure 3. Process Engineer functions The tests included the following: creation of the digital product model, creation of the process flow and manufacturing concept, creation of the manufacturing concept including the definition of process and assembly system library, and the preparation of the digital models of assembly system, creation of the assembly documentation, creation of the process simulation and the ergonomic analysis of work stands. Several computer systems were used during the development, including the software for MTM analysis, line balancing, and assembly process simulation. Fig. 4 shows the graph of manufacturing concept. The nodes of these graphs represents the manufacturing stands, while the relations between nodes represents the flow of the production process (Fig. 4a). Each manufacturing stand has assigned product elements being processed on it. It has also assigned process activities like manufacturing, assembly, testing and non-value adding operations. The manufacturing resources including the transport means and workers are also assigned to nodes of manufacturing concept. The fragmentary layout of resources used in manufacturing concept is presented on Fig. 4b. The initial versions of manufacturing concepts were continuously improved by using results of computer analysis available in PLM system in an iterative manner, as described previously. For example, the ergonomy was examined in details (Fig. 4c).

7 Concurrent Development of Products, Processes and Manufacturing 43 a) b) c) Figure 4. Verification steps: a) Manufacturing concept, b) Line layout, c) Ergonomic analysis 5 Conclusion The proposed methodology using PLM components like DELMIA CATIA and Process Engineer allows to increase the integration level of the process planning and assembly system design. It covers various design aspects including: normalization of the duration times of assembly activities, balancing of production line.

8 44 J. Duda and J. Pobożniak On the current level of implementation of integrated process design, MTM, MOST and BLP methods are used together with associated systems. Further actions are needed to include the following design aspects: analysis of manufacturing variants, throughput analysis, cost estimation, layout design. Nevertheless it should be noted the PLM solutions are only the tools speeding up the organizational and process planning stages of production preparation. The key condition to receive the good results are high qualifications of designer, process planners and manufacturing organization engineers developing the system components. 6 References [1] Chlebus, E. (2000), Techniki komputerowe CAx w inżynierii produkcji, Warszawa. [2] Chlebus, E., K. Oczoś, B. Dybała and T. Boratyński, (2000), Nowoczesne technologie w rozwoju wyrobu, Prace Naukowe Instytutu Technologii Maszyn i Automatyzacji Politechniki Wrocławskiej, Nr 78/2000. [3] Duda, J. (2004), Wspomagane komputerowo generowanie procesów wytwarzania obecny stan i perspektywy rozwoju, III Forum Integracyjne Polskiego Stowarzyszenia Upowszechniania Komputerowych Systemów Inżynierskich ProCax, Jedlnia. [4] Eversheim, W., H. Rozenfeld, W. Bochtler and R. Graessler (1995), A Methodology for Integrated Design and Process Planning on a Concurrent Engineering Reference Model, Annals of the CIRP [5] Eigner, M. (2004), Product Lifecycle Management The Backbone for Engineering, First International Conference, Virtual Design and Automation, Poznań. [6] Kahlert, T. (2004), From PDM to PLM from a workgroup tool to on enterprise wide strategy, First International Conference, Virtual Design and Automotion, Poznań.