Thermal imaging for developing a Solar Car

Thermal imaging for developing a Solar Car

Students use thermal imaging for

Developing a Solar Car.

The 21Connect is the Solar car with which Solar Team Twente
reached the fifth place of the World Solar Challenge 2011

Application story

Every other year since 1987, teams from all over the world are participating at the World
Solar Challenge in Australia. In a friendly competition the teams depart Darwin with
their own designed and build solar cars aiming to be the first to arrive in Adelaide, about
3,000 km to the south.

Solar Team Twente, a group of 16 students from two Dutch Universities, the Saxion
University of applied sciences and the University of Twente, have put their studies on
hold for a year and a half to attempt a first victory as the 5th team from Saxion and the
University of Twente participating since 2005.

Solar Team Twente is functioning as a completely
independent student endeavor.
The team members design, build and test
the car themselves and are independently
looking for opportunities to cooperate with
businesses, educational institutions and the
media. However, there is more to it than just
a team of 16 students. A team of partners
and advisors, as well as a large group of college
and university students are involved in
the project to gain new experiences and win
the challenge together.

Technological progress and innovation are
absolutely vital for the team. The team
combines many techniques into a complex
system to form a solar car. One of the techniques
used for the development of the car
is thermal imaging.

Finding thermal imaging

One of the prior teams of Saxion and the
University of Twente found out about thermal
imaging when visiting a local trade
show. The team immediately saw an application
to utilize this technique for the
development of their solar car. Already
being in a final stage of the development
of their car for the World Solar Challenge,
they only used a thermal imaging camera
for inspecting the solar panels before and
during the race. With the experience of this
team, the current solar team was able to
use this technology from the beginning of
their solar car development. They therefore
approached FLIR Systems to support the
team by making a thermal imaging camera
available for this ambitious project.

Solar Team Twente used the FLIR T450sc portable thermal
imaging camera with a rotating optical block, touch
screen interface and with a 320 x 240 pixel resolution.
Caliper, after performing brake test
Brake, immediately after performing emergency stop

www.flir.com

Applications

The main reason for using thermal imaging
for the development of the solar car is for
the team to confirm that the different parts
of the solar car are working as calculated
and according to the specifications in the
regulations defined by the organizers of the
World Solar Challenge.

The brakes of the solar car were some of
the most important par ts that needed
to be tested and where thermal imaging
came into play. “Driving at an average
speed of 50 km/h, the car must be able to
undergo a braking test where it needs to
be in complete standstill within a certain
distance for safety reasons.”, says Chiel De
Wit, Chief Product of Solar Team Twente.
“ To test this, we took a mock-up of the
solar car to a nearby airport where we
could test the car in complete secrecy, as
we don’t want to take any risk in revealing
the technologies we use to finish first in
Adelaide.” With the thermal imaging camera
the increasing heat of the brake discs
was measured at different speeds so that
it could be confirmed that these met the
specification set in the regulations. Also
the engine of the solar car was inspected
with the thermal imaging camera when
testing its maximum capacity. “Although
the engine also has heat sensors installed, a
thermal image gives a lot more information
than the sensors.”

Saving power

Energy efficiency is key when it comes to
finishing the race first. “ The less power the
different parts of the car are using during
the race the better, as this will mean more
power will be available to drive the solar
car”, Jelle Wagenvoort, Technical Manager
and member of the management team
of Solar Team Twente, explains. “ We used
the thermal imaging camera to test the
electronics of the car to see which parts
consume the most power and to decide if
we could replace or modify these”.

Start-up circuit
Solar panels

The solar panels on the solar car, converting
the sun’s energy into the electricity thrusting
the solar car, are without a doubt the most
important parts. The photovoltaic cells, the
most important part of a solar panel, must
be reliable and able to continue producing
electricity for the duration of the race.
To ensure good quality, a thermal imaging
camera can play an important role. The
use of thermal imaging cameras for solar
panel evaluation offers several advantages.
Anomalies can clearly be seen on a
crisp thermal image and – unlike most other
methods – thermal imaging cameras can be
used to scan installed solar panels during
operation. “A nominal loss of the production
of electricity can occur when one or more
photovoltaic cells in a solar panel are damaged”,
De Wit says. “It is very important to
make sure the solar panels are in excellent
condition before starting the race, but also to
check the panels during the race so that we
can repair or replace defective solar panels.”

Handheld thermal imaging camera

FLIR thermal imaging cameras are widely
used around the world for a variety of
applications. Numerous new products have
been developed with the help of a thermal
imaging camera. Thermal imaging cameras
are used for capturing and recording thermal
distribution and variations in real-time,
allowing engineers and researchers to see
and accurately measure heat patterns, dissipation,
leakage, and other temperature factors
in equipment, products and processes.

Solar Team Twente used the FLIR T450sc
portable thermal imaging camera with a
rotating optical block, touch screen interface
and with a 320 x 240 pixel resolution.
Handheld thermal imaging cameras as the
FLIR T450sc are perfect for dynamic testing
in the field. “Using this thermal imaging
camera was very convenient as we have
used it for different tests at different locations”,
says Wagenvoort. “It was the first time
we worked with a thermal imaging camera

and are very pleased with the quality and accuracy of the thermal images.”

The FLIR T450sc thermal imaging camera can
distinguish temperature changes as subtle as
0.04°C. They feature state-of-the-art detector
technology and advanced mathematical
algorithms for high performance and precise
measurements from -20°C to +1,500°C.

Conclusion

“ The use of a thermal imaging camera has
helped us a lot during the development of
our solar car”, De Wit continues. “Without
the use of a thermal imaging camera we
would not have known for sure if some parts
are working in the way as we thought they
were working.” The use of a thermal imaging
camera is not only a valuable technological
addition in the development phase of
the solar car, but also during the race. “Our
goal is to finish and win the race within
four days”, Wagenvoort adds. “ There will be
several moments during the race where we
will need to service the solar car. Besides
inspecting the solar panels with a thermal
imaging camera, we will use it for identifying
electrical components that will need cooling.”
Cooling of components is only allowed
with water of the same temperature of the
environment. “As no artificial cooling methods
are allowed, it is very important to identify
overheated components as fast as possible
to prevent any damage that would slow
us down. With the help of thermal imaging
we are confident we have developed a solar
car that will give us a head start with respect
to the competition”, Wagenvoort concludes.