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of software development and application motor sport is the use of a driving simula- times can be evaluated with greater accu-
is gaining importance. However, this does tor with a motion platform. Simulator racy through offline simulations as the
not eliminate the need for comprehensive specific hardware and software are not variance of a human driver does not
hardware development. Chassis and drive regarded as core competencies and are apply in this case.
control systems help tap into all the therefore procured from a system supplier In-house development of tools has sev-
potential offered by the overall system. (VI-grade). However, the same vehicle eral advantages:
In the LMP1 racing car, new software model developed in-house and used in – Models and evaluation software serve
versions can also be developed and the remaining simulation tools is used as as an executable knowledge database
introduced between races. In contrast the vehicle model and integrated into the and communication platform for all
to hardware development, this brings simulator environment. The use of the users, allowing for a lively exchange
improvements to the vehicle without simulation models can therefore also be between all the departments involved
involving major lead times. For road extended to the area of subjective evalua- as well as between motor sport and
vehicles, it is also already technically tion by the driver. The driver is essen- series production developers. Custom-
feasible to retrospectively load new soft- tially serving as an evaluation tool, ised integration into the processes
ware versions into the customer vehicle. whereby subjective impressions are used ensures that they can be used effi-
However, new functions can only be in addition to objective key figures in ciently and with ease.
tested using model-based variant studies order to evaluate handling. The vehicle – In-house development significantly
due to the high number of vehicle, model model delivers reproducible, deterministic improves understanding of both tools
and software variants. behaviour in a safe but still sufficiently and vehicle handling. It provides the
realistic environment. This permits rapid opportunity for quantitative evaluation
SIMULATION AS AN development and meaningful preliminary and creation of objective and authori-
EXCHANGE PLATFORM synchronisation of connected functions tative key figures.
that are relevant for handling. A positive – Using methods, models and evaluation
One of the core competencies at Porsche side effect of using the same vehicle programmes jointly across projects and
during vehicle development is objective model for this type of application is the departments automatically creates the
evaluation of vehicle dynamics. Although increase in model quality across the mod- need for close collaboration and com-
commercial software packages are availa- el’s entire application area. Evaluating lap munication and therefore ensures a
ble for this task, Porsche prefers to use times on the driving simulator is particu- constant exchange of knowledge
tools developed in-house for simulation larly useful for issues relating to vehicle between the different areas in the
of vehicle dynamics and objectification stability limits. In contrast to offline sim- development centre. It also results in
of vehicle handling. All models and pro- ulation, a human driver cannot tap into common metrics and a common lan-
grammes developed in-house are pro- the entire theoretical potential of a vehi- guage for describing driving physics. In
vided centrally for motor sport and series cle. Vehicle handling close to the individ- addition, tool extensions and improve-
production applications. In areas where ual stability limit has a significant influ- ments will benefit all users, FIGURE 2.
competition is less relevant, it makes ence on the lap times a human driver – In-house models and evaluation tools
more sense from a strategic perspective can achieve. On the other hand, there make it possible to work in a very quick,
to use commercially available products. are questions that are better answered flexible and efficient way and to quickly
An enhancement for tools developed through offline simulation. The influence adapt to new requirements, different
in-house that is particularly helpful in of changed driving resistance on lap vehicle concepts and new systems.

2.0-l V4 turbo petrol engine

Li-ion battery

Exhaust energy recovery system

Electric machine at the front axle
FIGURE 1 Technical details of
Porsche 919 Hybrid (© Porsche)
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