| Summary: | A combination of environmental awareness, consumer demands and pressure from legislators
has led automotive manufacturers to seek for more environmentally friendly
alternatives while still meeting the quality, performance and price demands of their
customers. This has led to many complex powertrain designs being developed in
order to produce vehicles with reduced carbon emissions. In particular, within the
last decade most of the major automotive manufactures have either developed or announced
plans to develop one or more hybrid vehicle models. This means that to be
competitive and o er the best HEV solutions to customers, manufacturers have to
assess a multitude of complex design choices in the most e cient way possible. Even
though the automotive industry is adept at dealing with the many complexities of
modern vehicle development; the magnitude of design choices, the cross coupling of
multiple domains, the evolving technologies and the relative lack of experience with
respect to conventional vehicle development compounds the complexities within the
HEV design space.
In order to meet the needs of e cient and
exible HEV powertrain modelling within
this design space, a parallel is drawn with the development of complex software
systems. This parallel is both from a programmatic viewpoint where object-oriented
techniques can be used for physical model development with new equation oriented
modelling environments, and from a systems methodology perspective where the
development approach encourages incremental development in order to minimize
risk. This Thesis proposes a modelling method that makes use of these new tools to
apply OOM principles to the design and development of HEV powertrain models.
Furthermore, it is argued that together with an appropriate systems engineering
approach within which the model development activities will occur, the proposed
method can provide a more
exible and manageable manner of exploring the HEV
design space.The
exibility of the modelling method is shown by means of two separate case studies,
where a hierarchical library of extendable and replaceable models is developed in
order to model the di erent powertrains. Ultimately the proposed method leads to
an intuitive manner of developing a complex system model through abstraction and
incremental development of the abstracted subsystems. Having said this, the correct
management of such an e ort within the automotive industry is key for ensuring
the reusability of models through enforced procedures for structuring, maintaining,
controlling, documenting and protecting the model development. Further, in order
to integrate the new methodology into the existing systems and practices it is imperative
to develop an e cient means of sharing information between all stakeholders
involved. In this respect it is proposed that together with an overall systems modelling
activity for tracking stakeholder involvement and providing a central point for
sharing data, CAE methods can be employed in order to automate the integration
of data.
|
|---|
