Read about what we have achieved throughout the year and how we faced our challenges as a team
The final days of the year are approaching, but the work within our team continues at full speed! Since receiving the new regulations for the Bridgestone World Solar Challenge 2025 this summer, we have embraced the challenge with great enthusiasm. The team has grown, and every member has found their role, laying the foundation for strong collaboration and a clear direction moving forward. The new regulations have truly pushed us to think outside the box, leading to exciting innovations and creative solutions. The planning and design of the new car have demanded significant effort and thought, but we are pleased to announce that the construction phase is now underway. We have a clear plan and are working step by step to bring our vision to life.
Over the past few months, we have focused on optimizing all aspects of the project – from design and production to strengthening team spirit and collaboration within the various sub-teams. We firmly believe that our strength as a team is one of our greatest assets and that our shared focus will propel us forward. Our goal is clear: not only to build a car capable of crossing Australia but also to showcase to the world what Swedish engineering and innovation are all about. We look forward to continuing this journey together and extend our gratitude to our partners for your invaluable support. Without you, this project would not have been possible.
The coming months will be crucial as we prepare to take significant steps in the production and testing of the car. We have also already begun planning the logistics and strategy for 2025. We know the competition will present tough challenges, but we are more than ready to face them with determination and team spirit.
In closing, we would like to express our gratitude to everyone who has supported us along the way – from partners and school leadership to friends and family. Together, we are building something we are incredibly proud of, and we look forward to sharing more successes with you in the future.
Thank you for your commitment and trust. Let’s continue working hard and aim for the stars!
Best regards,
Emma Christiansen
Team Manager
With the new regulations released last summer giving us the opportunity to have 6m2 of solar cells, Mechanical took the big decision of moving away from the Bullet design of the car. This meant that a lot of the work that was performed up until summer now was obsolete and we had to start over.
Now that Christmas is right around the corner, we are happy to report that even though the fall started with this big setback, we are well underway. We have already started manufacturing the molds for the carbon fiber, and as we write this, we are also producing a mockup for testing and verifying the wheel suspension and rear frame.
Monocoque:
The design of the monocoque is finished and optimized to improve the strength while also maintaining a low weight. The molds that we are going to bring to Marströms Composite AB for the carbon fiber casting are well on their way. We are extremely grateful for companies like Marströms Composite AB, DIAB and Dormer, which support us with materials, knowledge, and
access to machines and tools that we would otherwise struggle to acquire.
Aerobody:
As of today, the aerobody is finished. Simulations revealed that aerodynamics is the most important aspect of the car. Because of this, we chose to get help with the milling of the mold from Macromould and their special paste. This saved us approximately 500 hours of milling and sanding of the mold, allowing us to truly optimize the aerodynamics of the car.
Wheel Suspension and Rear Frame:
We have mostly completed the design and simulations of the rear frame. We are now investigating whether we can make it even lighter while maintaining the strength needed. We also started a collaboration with Hygap AB to further improve our ways
of production processes by utilizing their expertise in 3D laser cutting and bending steel tubes. To test and verify the front suspension, we decided to create a monocoque in wood. This will serve as a test rig until all the carbon fiber parts are finished.
Best regards,
Max Elofsson
Head of Mechanics
The past half year, we have worked towards gathering as many partners as possible.
New members have joined the team, and together with them, we have been trying
to optimize our work by having at least two people in every category of marketing
and collaboration. The design team has worked together with Jac Tryck to help us
get team clothes.
During the summer before the term started, we were in contact with Region
Halland and Invest in Halland regarding the Evertiq Expo in Gothenburg, where they
invited us to join them. At the start of the term, we drove to Falkenberg
Motorbana to gather data for Belgium together with JUST.
The Evertiq Expo coincided with the iLumen European Solar Challenge in Belgium.
While the team and Sven were in Belgium competing, the rest of the team in
Sweden joined the expo.
The process leading up to Belgium involved planning how many cars we would take,
including arranging for a suitable car to tow the trailer that was hired. While there,
the team discussed with other countries’ teams our differences and similarities,
which helped us learn from each other. Shortly after Belgium, we visited the Elmia
Subcontractor event, where we met some of our partners and sought new ones.
Not long after, we organized an event together with the Chalmers Solar Team,
where we exchanged knowledge and interests.
Best regards,
Josefin Saladdin & Yashar Asadzadeh
Head of Marketing & Head of Collarboration
Changes to the Electrical System Before Belgium
Before our trip to the competition in Belgium, several modifications were made to Sven, the car that competed in BWSC23.
LV (Low Voltage):
On the low-voltage side, an entirely new electrical system was developed, reducing standby power consumption by approximately 30%. To achieve this, new circuit boards were designed.
In this system, the entire car was controlled by a single microcontroller, which handled everything from saving and displaying data for the driver to controlling the motor and various lights. The microcontroller was mounted on a circuit board in the steering wheel and communicated with the rest of the car via I²C and CAN-bus. Additionally, a new telemetry system was required since, unlike in Australia, there was no follow car during the competition. However, mobile coverage was available, allowing us to develop a 4G solution which provided 24-hour live data transmission without any issues.
HV (High Voltage):
When Sven returned from Australia, it was evident that one of the battery cells didn’t have the capacity it should, as its voltage dropped faster than the others. This needed to be addressed immediately for both safety and performance reasons. We decided to rebuild the half of the battery pack containing the faulty cell. For cost reasons, the entire battery wasn’t replaced. This repair enabled us to run the car for 24 hours without any problems.
Best regards,
Oscar Pålsson
Head of Electrical
Belgium was a great experience and an excellent opportunity to introduce the
new members of the Mechanical team to the old car, allowing them to learn
more about its flaws and what they should improve for the new car.
Before the race, we decided to replace the front damping system used in
Australia with a monoshock system. This change was made to reduce weight
further and improve anti-roll effects during turns, which are more frequent
and sharper in the Belgian race compared to the Australian one. During the
race, Sven proved to be as reliable and sturdy as in Australia, with the only
required repair being a brake pad replacement.
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Since Sven’s return from Belgium, all focus has shifted to designing an entirely new electrical system for the next car.
LV (Low Voltage):
On the low-voltage side, each person has been assigned a specific part to take responsibility for. This approach allows
us to optimize each component individually and increase complexity to reduce power consumption.
Each circuit is simulated independently, with the goal of halving the idle power consumption of the car. This is being
achieved by replacing mechanical relays with more advanced semiconductor circuits and by lowering the voltage across
high-voltage contactors after they are initially closed. All these efforts aim to save as much energy as possible.
HV (High Voltage):
On the high-voltage side, the focus has primarily been on redesigning the solar array and battery. The new rules for the
2025 competition require an entirely new solar array and a battery with significantly less capacity.
The battery has been a challenge under the new regulations, as we aim to maintain a relatively high voltage for better
efficiency. This is difficult when the battery capacity has been reduced from 5 kWh to approximately 3 kWh. Final tests
and drawings are now in progress before the battery construction begins. Our partner MATTR Collective AB has, as
always, been of great assistance with design choices and expertise regarding the battery pack.
The placement of the solar cells has been developed through extensive collaboration between the Electrical and
Mechanical teams. The goal was to fit 6 square meters of solar cells in as small an area as possible, without
compromising the car’s aerodynamics. This work is now complete, and the cells, supplied by Sunpower, are ready to be
sent for lamination to our new partner Ensten, where the cell-surface and celinterconnections will be manufactured.
This surface not only protects the cells but also increases the power output under varying sun angles.
We’ve built a completely new test rig to evaluate our custom-built solar car motor. This has provided us with a wealth
of useful data that will guide our strategies for determining the most efficient speeds, giving our strategists significantly
more insights than before.
Best regards,
Oscar Pålsson
Head of Electrical
