SVOC – FST - Západočeská univerzita v Plzni

PRODUCT LIFE CYCLE IN DIGITAL FACTORY
SVOČ – FST 2011
Ondřej Kurkin,
West Bohemia University,
Univerzitni 8, 306 14 Pilsen
Czech Republic
ABSTRACT
This paper is focused to the usage of digital factory concept in the design of the product and its production system. It is
similar to PLM and includes product design, its engineering and technological design, the proposal of the production
system for the product and its validation using ergonomic analysis, and the final section is the simulation of production.
From a global perspective, one can conclude that the production system is considered a product.
KEYWORDS
Digital Factory, PLM, Simulation, Ergonomic
INTRODUCTION
New Product Development in the Digital Factory can be divided into several stages:
Concept of product
The design concept of designer engineer
Production technology
Designing of a workplaces
Designing of a production system
Ergonomic analysis of workplaces
Simulation of the production
Implementation of the project
DESIGN OF THE CONCEPT
Designer creates the products to meet customers’ needs according to the demand suggested by research. It is an idea of
appearance and function rather than the products capability and appearance. This proposal is designed for engineers in
their work. In our case, we chose RC model of car as our product.
Fig. 1. Design of the concept
ENGINEERING DESIGN
Engineering designer makes documentation for the technology. His aim is to design individual parts of the assembly
that the total product meets all the required functions. There are a design tools (CAD systems) which are part of a
package of digital factory for this purpose. There are only two companies which are providing full package of Digital
Factory.
Dassault systems (with CAD system Catia)
SIEMENS (with CAD system NX)

These engineering tools allows designer to:
Design of individual components of the product
Static and dynamic analysis
Virtual simulation and report completion of its functionality
Creation of technical documentation for technology
In our case, we chose a suspension arm for the stress analysis and analysis of the technology.
Fig. 2. Examples of work in design tool NX
TECHNOLOGICAL SOLUTIONS
After that the designer creates drawings, process engineer begins with designing of the manufacturing process for
individual components and their subsequent assembly into a complete assembly. The manufacturing process means:
Choosing of working machines and tools for the production of individual components
Determination of working conditions
Generation of CNC programs (if there are used CNC machines in the production)
We can use of technological modules which are parts of the CAD systems (CATIA and NX). These modules allow
engineers to virtually simulate a manufacturing process. Technologist can choose:
Method of machining
Cutting machining conditions
The control system of CNC machine
Analyze a precision after machining
On Fig.3 you can see a design of injection head for production suspension. There is example of machining of the main
board of the injection head. When control system is defined (in our case SINUMERINK) technologist can simulate a
progress of machining. It can simulate only a cutting tool or whole machine. The biggest advantage of this
technological module (in case of NX) is that we can simulate that the machine runs directly according to the CNC
program. In many other technological tools, the simulation is run only by the CL data, which are not gone through the
post-processor.
Injection Head
Simulating of the
cutting tool
Simulating of the
machine
Analysis of a precision
after machining
Generated NC
program
Fig. 3. Examples of technological operations in NX

DEFINING OF THE PRODUCTION PROCESS
When technology is ready for production, according type of a production industrial engineer has to design production
process. Industrial engineer has to:
Design a production processes
Set the tact of the production line
Design a individual workplaces
Design a manufacturing system
Design a supplies
Ergonomic analysis of workers
We will use package digital factory for this purposes again. In our case, the production system is modeled in product
Tecnomatix.
Design of the processes is divided to several steps:
Rough planning
Fine planning
Simulation and verification of the fine planning
Ergonomic analysis of the workplaces
Discrete event simulations of the manufacturing system
ROUGH PLANNING
There are defined resources, products and processes of individual operations in rough planning. We use the Process
Designer for these tasks.
Resources
Resources encompass everything needed to ensure the process eg workbench, tools and workers themselves. The Fig.4
shows the layout of resources.
Fig. 4. layout of resources for production of RC car
Products
Products are components of the input and output sub-assemblies of components or assemblies. In our case, Products are
parts of a RC car. On Fig.5 You can see tree of parts and assemblies of our mode
Part of RC car
Fig. 5. Product tree
Product tree

Process
The process changes inputs to outputs using resources. We split an operation to sub-operations in rough planning eg:
vice a part to mounting device or move the box with the material. The big advantage of the Process Designer, are time
tables with the MTM codes. You can simply define an operation eg: fixing a part to mounting device and Process
Designer automatically calculates according a MTM codes operation times.
FINE PLANNING
Process Simulate serves to verify of assigned times from Process Designer. Process Simulate is a simulation tool for
real simulations such as human motion in the assembly operations. Operations are defined to the sub-tasks such as
finger grips for gripping parts, etc. After running the simulation, we have a new (simulated) times of operations. This
new times will be compared with times from Process Designer. We can decide which time we will use in project.
The Fig.6 shows the difference in the times from Process Designer and Process Simulate. Process Simulate is also used
for verifying collisions in automated robotic manufacturing. Simulations of robot motions can help with organizing of
workplaces. On Fig.6 the lower picture shows more detailed planning of operations. There you can see a difference in
time of first sub-operation. Difference in time is 0.3 seconds compared to rough planning
Fig. 6. Rough and Fine Planning
ERGONOMIC ANALYSIS
We are testing an individual workplace after defining the operations, resources and products. There is a ergonomic tool
JACK for this tasks. This tool contains a realistic model of a man with ties to the bones, muscles, joints, etc. You can
set a male of human, weight, height. All these proportions affect a human at work.
According to the results of each analysis, it is necessary to modify the workplace for the worker. After this we can again
simulate a production process in Process Simulate. This cycle is repeated until we achieve the best results.
Fig. 7. Ergonomic tool JACK

DISCRETE EVENT SIMULATION
The last part of the package of Digital Factory is a simulation tool Plant Simulation for discrete simulations of
manufacturing processes. After ergonomic analysis in JACK, we can export a data from Process Designer to Plant
Simulation. We can simulate different situations which can occur in production process. We can define cost time,
number of scrap, machine failures, etc. and in the report we can see eg costs per period, investment per period number
scrap etc.
Fig. 8. Discrete event simulation, in Plant simulation 9
CONCLUSION
In today's globalized era, Ahead of the competition means a distinct advantage in the market in today's globalized era.
Every investment should be very well considered. The biggest advantage of the Digital Factory is that everything
happens in the virtual world. It is possible to test numerous scenarios and problems that might arise in real business.
When a problem occurs in the virtual model is not difficult to remove it, but in real company are these solutions of any
problems very expensive. Another big advantage is the data consistency. We have a data format which can work with
all of the tools of the package.
The cost of the digital factory is only the cost of time spent preparing the virtual model and the cost of software. Each
enterprise must consider whether it is advantageous to him the whole package or just some debris from the instruments.
In our example is shown in virtually all life-cycle of the product to distribution of the product (not included here to
return the product). Each tool can be used separately.
ACKNOWLEDGMENT
This paper was created with the subsidy of the project 402/08/H051 under the Grant Academy of the Czech Republic.
The name of this project is “Optimization of multidisciplinary design and modelling of virtual firm’s production
systems”.
REFERENCES
[1] TUPA, J.; KAŠPAR, P.; BASL, J. Process Performance Management Application for Technological Process Control. In
Proceedings of the 17th International Conference on Flexible Automation and Intelligent Manufacturing. Beijing : Hongde
Tongda, 2007. s. 460-467. ISBN 978-1-4276-2092-7
[2] VOTAVA, V. – ULRYCH, Z. – EDL, M. - KORECKÝ, M. – TRKOVSKÝ, V. Analysis and Optimization of Complex Small -
Lot Production in New Manufacturing Facilities Based on Discrete Simulation. In: 20th European Modeling & Simulation
Symposium (EMSS 2008), Campora San Giovanni, Amantea (CS), Italy, September 17-19, 2008. ISBN 978-88-903724-0-7.
[3] Saaty L. T. & Vargas G. L. (2006). Decision making with the analytic network process: economic, political, social
and technological applications with benefits, opportunities costs and risks, Springer Science + Business Media,
LLC, ISBN 978-0387-33859-0, New York, USA
[4] Internal materials and manuals from SIEMNS PLM Software
[5] BANKS, J., CARSON, S J., NELSON L B., NICOL, M D. (2005) Discrete-Event System Simulation, Pearson Prentice Hall,
New Jersey ISBN 0-13-088702-1
[6] Votava, Václav. Simulace ve strojírenství. 1. vyd. Plzeň : Západočeská univerzita, 2008. ISBN 978-80-7043-659-2.
[7] ŠIMON, M. and ČERNÝ, Z.(2009): Strategic planning of joint logistics at the level of horizontal cooperation, In Annals of
DAAAM for 2009 & Proceedings of the 20th international DAAAM symposium, 2009, str. 657-658, ISBN 978-3-901509-70-4
[8] Internal materials and manuals from SIEMNS PLM Software