SUPPLIER INTERVIEW: CLAYTEX
A safe future
As vehicle complexity increases, the need for more physical testing can
be negated by the use of careful and e cient modelling and simulation
WORDS: KARL VADASZFFY
One of the objectives for automotive
OEMs over the past decade has
been to try to reduce the number
of prototypes and the amount
of physical testing required. Yet
as system complexity has increased, so the
number of diff erent types of tests that need
to be carried out has risen substantially.
Through careful use of simulation, however,
it is now possible to use virtual testing to
replace many physical tests.
As a developer and distributor of modelling
and simulation tools for systems engineers,
Claytex has been working on the development
of tools and methods to enable the use of
physics based models in virtual test
environments for more than 20 years.
The company uses DYMOLA to model all
the vehicle systems, from the battery, power
electronics and motors to the mechanics of the
suspension and fl uids in the cooling systems.
Mike Dempsey, the company’s founder and
MD, explains, “We take the physics models and
embed them in another simulation tool, rFpro,
which enables users to drive vehicles around
diff erent locations and scenarios. This can be
used as a driver-in-the-loop or autonomous AI
system-in-the-loop to see how the complete
vehicle – its sensors, control systems and
physics – work and operate together.”
140 // January 2020 // www.electrichybridvehicletechnology.com
“gives users complete control over everything,
making it possible to repeat the same test time
and again while exploring how changes made
to the system will improve the response,”
Dempsey says.
The introduction of simulation has not
been responsible for reducing the amount of
physical testing that is needed, but Dempsey
says it prevents far more testing from being
required. “In reality, what simulation means
is that you’re not necessarily having to increase
the level of testing, despite the extra complexity
of everything that is being put into vehicles.”
Hot topic
Developing electric vehicles brought
along new challenges. In the early days
of EV development, these centered around
thermal management and how to manage
the temperatures not only of the electric
systems, but also in keeping occupants
comfortable, Dempsey says.
“Without an internal combustion engine
producing lots of waste heat that can be
harnessed, we’ve had to explore heat pump
technologies, looking at how to capture the
available heat and transfer it e ciently around
the system so that we can optimize the energy
usage,” he adds. “Using our solutions, we can
objectively measure human comfort in the
vehicle cabin and adjust the behavior of the
HVAC system to keep the occupants feeling
comfortable, while keeping all the systems in
the car within their preferred operating ranges
and minimizing the overall energy usage.”
1. Claytex has developed an
rFpro simulation with Lidar
sensor model for testing
autonomous vehicles
2. Simulating an entire
autonomous vehicle allows
Claytex to test for scenarios
such as pedestrians
stepping into the road
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Using models that are based on physics is
particularly important, Dempsey says, because
they mean “we are using predictive models
rather than models that are characterized from
data that’s been already measured, so we can
do a lot more simulation up front, early in the
design cycle, to work out if the system is going
to do what is expected and required.”
As the complexity of modern vehicles
continues to increase, he suggests that
“physical testing alone is not enough because
there are so many variables that can’t be
controlled in the real world, which makes
it hard to repeatedly do the same test.” The
opposite is true with simulation, which
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