Due to increased competition and customer demand, products must be more
and more functional, compact, innovative and cheap. To resolve these
conflicting requirements, a new way of design is needed that results in
products that provide the desired functions, but does not increase the
cost of the design (and hence of the product) or the time-to-market.
The mechatronic design approach puts various design activities in
parallel, thus reducing the time needed to complete the design, and
also exploits the interaction between different subsystems (different
domains) to optimize functionality and cost.
An integrated design approach like the mechatronic approach does not
allow for extensive prototyping since the dependencies between the
various domains would 'deadlock' the design process. Instead, more
rapid ways of model analysis, such as simulation, are used to judge the
design throughout the process. The model 'grows' with the increasing
amount of knowledge acquired in the design process.
To ensure optimal integration, a joint model of the overall design is
essential. For that purpose, a domain-independent description must be
used as the backbone of the modeling process. This backbone can be
augmented with additional descriptions to further illustrate or analyze
specific parts of the design.
Recognizing the fact that modeling and simulation are currently
scattered activities in many cases, the OLMECO project aims at
providing an integration between the modeling and simulation tools by
providing an open (paradigm- and tool-independent) environment for
storage and exchange of model data. Even more important than its role
in streamlining the modeling process, OLMECO provides a library of
pre-established models which are available for re-use. The combination
of re-use and rapid exchange leads to a substantial increase in
productivity.
The OLMECO project is carried out in the framework of the CEC program
ESPRIT-III. The project started 1 September 1992 and will be concluded
1 November 1995. The section below briefly describes the partners
forming the project consortium.
Project Partners
The project is performed by a consortium that has a unique structure
since three roles can be distinguished among the partners:
End Users
The requirements for a model library are best recorded from the
source of the modeling (for design and analysis), in other words,
the (prospective) end users. To avoid a bias towards a single
domain of application, two major application areas are represented
in the project.
The automotive domain is represented by PSA Peugeot-Citroen
(leading partner in the project) and by Imagine, both based in
Paris, France. PSA is a major car manufacturer in Europe and
closely cooperates with Imagine, a consulting company with a strong
background in hydraulics. The main interest of the automotive
partners is to investigate the dynamic behavior of automotive
components in multiple domains.
The machine tool domain is represented by machine tool manufacturer
Fagor and consulting and technology transfer company Ikerlan. Both
companies are based in Mondragon, Spain. The machine tool partners
are migrating from a typical mechanical engineering application to
a true mechatronic approach to the design of machine tools.
Modeling Specialists
Two project partners contribute their knowledge of the modeling and
design process and as such provide a theoretical basis for the
design of the library. The Control Laboratory of the University of
Twente (Enschede, Netherlands) has been involved in the development
of modeling and simulation software since the 1960's and
contributes this experience to the project; further they provide
some large-scale modeling examples based on lab setups. The
Netherlands Energy Research Foundation ECN (Petten, Netherlands)
has a similar role, but stresses the use of Artificial Intelligence
in modeling and design.
Software Engineers
The Belgian software company BIM Engineering Europe of Louvain-
la-Neuve is involved in all software development and provides a
solid background in database technology and software engineering.
This structure of the consortium ensures that a product results which
is both theoretically sound and practically useful in terms of
functionality and reliable and robust from a software product point of
view. Throughout the project, bilateral and multilateral discussions
take place to have a balance between the objectives and interests of
the project partners.
Results achieved so far
Library Structure
Based on discussions between all partners, the modeling specialists
and the software engineers designed a structure for the library
that enables the storage of all aspects of a model that are
relevant in a searching process. This structure is based on a
framework that can be used throughout the life of the models, and
is divided into a component level, a physical level and a
mathematical level.
The component level defines the functional relations between models
and provides a high-level description of the interaction between
subsystems. The physical level specifies the physical phenomena
that are relevant for the system and the context in which the model
is used. The energy-based bond graph approach is a useful paradigm
for this level. In the mathematical level, the actual equations
that describe the effects in detail are associated to the elements
of the physical level.
Library Content
To demonstrate the feasibility of the concept and to provide an
initial content of the library, all partners with modeling
activities have contributed a number of models to the library as it
will be demonstrated at the end of the project. The models range
from basic mathematical models via physical models to complete
component level models, including some sample simulations. The
models represent many engineering domains, for instance mechanics,
hydraulics, thermal models, electromechanical transducers, rigid
bodies, etc.
Even though the current content of the library is still small,
structuring the information is crucial for the rapid construction
of models and the quick assessment of alternatives. For this
purpose, the models in the library are classified in taxonomies,
which links models through a variety of associations. The
taxonomies provided by the project partners are compiled into a
single taxonomy by the modeling specialists.
Software
The library structure developed in the project is implemented on
top of a commercially available database system. The openness of
the library is guaranteed by a tool-independent storage format.
Various modeling and simulation tools can be used in conjunction
with the database, provided that an appropriate filter is
available.
The University of Twente has developed a prototype interface to the
library in the existing 20-SIM software, which is used for a first
evaluation of the library. In a separate project, PSA and BIM
cooperate to establish a link between the library and another
simulation package.
Future developments
The impact of the library in a practical situation is strongly related
to the amount of models present in it. Therefore, an important
development of the library will be filling it further with models and
model-related information. The information that is presently contained
in the library is not ideally accessible yet, so further classification
of models and the addition of new associations between models is
another important aspect of the further development of the library.
The software that is currently used to access the library has a
prototype status and is presumably insufficient for real-life
applications. Therefore, the software has to be made more robust, and
functionality has to be added, among others to fully exploit all
information that is available in the library. Further, the software
should be transformed into a competitive offer for use by mechatronic
engineers and be provided on a commercial basis.
Availability
OLMECO is a research project. This status is reflected in the
reliability of the software developed so far. For that reason, the
distribution is restricted to the project partners. However, the
software will be further developed and commercialized after the
project. You can monitor the latest developments of the product and
even influence the direction (to some extent) of further developments
by becoming a member of the OLMECO Extended User Group. Contact Jan
Broenink at the address below to join the Extended User Group.
Jan Broenink
Dept. of Electrical Engineering
University of Twente
PO Box 217
7500 AE Enschede
Netherlands
phone +31 53 4892793
fax +31 53 4892223
e-mail J.F.Broenink@utwente.nl
Associated Products
To use the models in the OLMECO library, a suitable modeling and
simulation package is needed. The 20-SIM package (formerly known as
CAMAS) developed at the University of Twente closely follows the
emerging capabilities of the OLMECO software, as the development team
has intimate links to the OLMECO project. 20-SIM is available through
ControlLab Products:
