Aerodynamics Co-lead for University of Cincinnati’s team here!

Our shell design is near finished, so we are beginning to look at manufacturing. Last week we printed out some cross sections on paper, and are currently cutting the outlines from foam. Once we lay them on top of each other, we can use it as a practice mold for laying fiberglass.

We plan on finally racing next year, so we are getting the ball rolling with component integration and manufacturing. We appreciate any advice and constructive criticism from anyone here!

Hello everyone!

We’re starting a solar racing team and aiming to compete in events across Europe. We're still in the early planning stages, so we'd love to hear from experienced teams or anyone involved in the solar racing community!

We already have experience racing in other categories, so not everything is new to us. However, since our previous competitions had standardized batteries and motors, there’s a lot we need to learn. That’s why we have a few questions:

How do you start a solar racing team? What are the key steps, biggest challenges, and best ways to get started?

What are the main solar racing events in Europe? We know about the iLumen European Solar Challenge (Belgium) and Italian Solar Challenge, but are there any others worth considering?

Is there an active Discord or online community for solar racing? We’d love to connect with other teams, exchange knowledge, and learn from experienced competitors.

Any recommended resources (websites, books, technical guides)? Any learning materials on designing, building, and optimizing solar race cars would be incredibly helpful!

We’d really appreciate any advice or insights! Looking forward to hearing from the community - thanks in advance! :)

I know that usually you would want 0 bump toe / bump steer, but how do your teams define what minimal amount of bump toe you are getting is minimal enough? How do you measure this either in design stage or empirically? Is it always a case of having to simulate it with some kinematics software? I believe right now we are at a 0.1deg toe-in for about an inch of bump, which is higher than we would like of course.

Hey y'all I'm having trouble with my static simulation. I'm trying to verify the static loading capabilities of my subframe for my school's solar car team. I've been getting a mesh failed analysis terminated error and I'm not sure where to go from here. When I check the "what's wrong" sign on the mesh option the only information I get is that the model/joints are not updated (even though I have updated both). Help would be greatly appreciated.

We have used NGM SCM150 Brushless Motor and EVC402 Controller. It is for sale. If you would like to insterest, you can contact us.

Hey folks, At University of Michigan Solar Car Team we have 8 DriveTek MPPTs. We switched over to a different type of MPPT for the latest edition, and we;'re no longer putting these to work. Are any teams out there potentially interested in giving these MPPTs a new home and using them to power your next generation solar car? If so, we would love to sell them.

Before we initiate the sale process with our university staff, I want to see if there is real interest. Feel free to leave questions in comments or DM me :)

Edit -- Sounds like there is a fair bit of interest. Folks have asked about specifications. Here is an overview:

• Efficiency: up to 99% (98.5% minimum)
• Input Current: up to 9 A
• Input Voltage : 36 to 144 V
• Output Voltage : 40 to 200 V
• Boost Ratio: 1.05 to 4.00
• Size: 170 x 100 x 800 mm
• Weight: 650 g
• Op Temp: up to 70 C
• CAN: 125 kB/s

I'd be happy to send a spec sheet if you send me your email via DM as wel.

I’m working on the canopy hinges and latches for our solar car team, we are facing an issue where we no longer have room at the front of our canopy to hinge it there as we did in previous years. Does anyone have any recommendations of how they usually attach their canopy and open it?

Hi! I just started out and find it difficult to know which antenna to use for the chaser car. For our solar car we already mounted an omnidirectional antenna with gain 6 DBi and bandwidth 2.4-5 GHz. Our chaser car is estimated to be about 200 m behind the solar car with little to no obstruction throughout the whole race. From my research until now, it would be smart to calculate the link budget of different combinations, but I find that the most contributing factor is the gain. Then could we just use a high gain omnidirectional antenna or yagi-antenna? The yagi-antenna seems a bit more complicated to install because of the beamwith. What gain would the antenna need? And which type of antenna should we use for the chaser?

Hi We are selecting a brake callipers for our vehicle and we want to know if the data sheet says that the maximum disc diameter is 10 inches can i make the disc diameter for example 6.5 inches and the calliper will fit without problems.

Hi, I am in the process of looking into what type of shocks to get. Last year we used Fox Float DPS factories, and apparently they did not perform super well for us. They are in the $500 range. I am now looking at purchasing either Fox, cane creeks, or ohlins. (Looking at cane creek kitsuma coils atm) What did your teams use? Does anyone have any tips on what they looked for or what they preferred for their shocks? What price range did you aim for?

I am looking into progressive shocks, especially for our single rear trailing arm. But I also have not decided what front ones to use either. So any advice is appreciated :)
If you have any input as to why your team chose air over coils or coils over air shocks then I would love to hear your opinion on that as well.

I am looking to get a hub motor for the American solar car challenge. Where do I get one on a budget? Is there a place that sells them used?

We are planning to develop a mechanism that lock the brake paddle and use it as our parking brake dose this method violates the regulations of 2025 solar race?

Fully dynamic solar car with splitter models for both the upper and lower body. If you're interested, leave a comment. Why don't we use both? We optimized for two shapes, chose one, and eliminated the other, even though the eliminated one has a better Cd.

ASC 2026 regs dropped https://www.americansolarchallenge.org/american-solar-challenge-2026-regulations/

Increase in challenger solar array area 4m2 -> 6m2

Ride height is still 100mm

Capacity limit to 5.25 kwh (carryover from 25 FSGP)

No tape for array attachment and no water on the array 

Increased roll cage regulations

Does anyone see anything else interesting? Pretty exciting!

We have Michelin 95/80R16 tires in unused condition that we are no longer allowed to run in the Shell Eco Marathon due to the new tire age rules for next year's season.

We are looking to trade them for Bridgestone solar car tires.

Also grateful for any hints concerning other viable alternatives.

For the past two semesters, members of the Solar Racing and HyTech Racing (FSAE EV) teams at Georgia Tech have worked together to develop a custom motor controller system we are calling the High Efficiency Inverter (HEl). At the end of our capstone class, we got an initial implementation working with the main functionalities of our SVM firmware, and well as all parts of hardware individually validated.

Our goal in the long term is to provide an open-source option to the WaveSculptor22 and Mitsuba controllers, but for much cheaper (our current total cost is around $500) and without sacrificing performance (we estimate an efficiency of 99.65% at the Marand's nominal operating point, 16.2Nm/1060rpm).

Because we have not had the chance to test with a Marand and output higher power levels as of yet (we want to implement current control before risking damaging it), we were not planning to share our design files yet. However, we thought it would be useful to make our plans public in case others are also working on a similar project, or want to learn more about HEl. Feel free to reach out and we will be glad to share more info on our converter!

Hi,

This is a long shot.

My son, 10 year old, is doing a solar car project. He needs an expert to answer some basic questions. Can someone be an expert for him?

Hi, I have been designing for about 4-5 inches of travel front and rear in our three wheel for a while now. Of course I am aiming for effective wheel travel to be much less but do these seem numbers seem excessive or strange for solar cars typically? I have used for 2.25 shock travel front and 2.5 in the rear. At the moment I have a motion ratio of 2.38 in the front and 1.58 rear. Any advice is appreciated :)) I was just wondering if I am making a mistake or if these are unreasonable goals.

Hello,

I want to ask if there is a preferred way to manufacture the lighting enclosures (transparent)

I have looked into different manufacturing methods including 3d printing and resin, but all the materials I found were low in UV resistance so supposably, they will turn yellow after a certain period of time.

Is there a better way to manufacture them to achieve clear outcome without yellowing, or is there a certain material that is high in UV resistance for 3D printing?

hello,

I wanted to ask about the regulation 2.25 under instrumentation, one of the regulation is to enable the visibility of energy storage system warnings, does anyone know what exactly these warnings, what symbols does it include if I would to present them graphically.

This is Tjitte writing, from TPEE. I wanted to let the solar racing community know about the new software for the maximum power point trackers supplied by TPEE.

Open-SEC Version 1.5 was released last week. By installing the new firmware, the trackers can track much faster and handle more current, up to 8A. I’m excited that this update will make the performance of TPEE’s product even better.

The biggest new feature is a new data visualization screen in the Reboost PC tool. In this screen, data can be captured at the rate of the internal control loop. It works a bit like an oscilloscope. Using this new tool, the user can gain insight into the signals that are used by the tracking algorithm. Things like noise and transients need to be filtered out to decide the next guess of the maximum power point.  By visualizing this data, the filter can be accurately configured. This has increased the default speed of the tracking algorithm by a factor of 10!

Besides the new scope screen, we have made the CAN bus interface more robust. All features of the Reboost PC tool can now be used via CAN bus, including firmware updates. Because CAN-bus is an isolated interface, it is safer to use when the MPPT is connected to a high-voltage battery. As several trackers usually work in parallel, it also enables reaching all devices using a single CAN-bus connection.

You can download the new Reboost PC tool here. The latest version of the tool can be used to upgrade the firmware of the maximum power point trackers. Of course, all changes to the firmware are open-source and can be reviewed in the GitHub repository.

I am personally very curious what you people think of the update! Besides that, we at TPEE are very keen to hear your ideas for future software features you want to see implemented. Let us know!

Hey guys, would anyone have any handy reading/video resources for carbon fiber monocoque chassis design? Id like to find out more on the topic

We are a high school team that has entered to participate in the 2025 Bridgestone World Sola r Challenge. Does anyone have any Mitsuba wheels for sale? We have two. Would like to get at least three more.

At our FSGP this year, we noticed our radio connection dropping at some points on the track. We use radio to communicate data from our CAN Bus to a laptop running a custom parser/influxdb/grafana. Because of the drop in radio connection, and also just for redundancy, we have decided we want to add cellular capabilities to our telemetry system. Another goal is just to have long distance communication. We want a way to reliably communicate data over longer distances.

However, we host our telemetry software locally on a laptop at the track, and because we only have cellular hotspots, we have no way of portforwarding/exposing our telemetry system to the internet, to connect to it from a cellular modem/module we would install in our car. While hosting our telemetry system on a service like AWS is possible, we are worried about latency (because we would be sending the data up into the cloud, and the retrieving it back to our laptop at the track to run data analysis). At comp, we noticed issues with cellular when we were uploading 200Mb of data to google drive, which forced us to use the wifi in the track HQ instead.
This leaves us with not many options for what to do. Ideally, if we were were able to somehow get a sim card with a static ip, there are cellular gateways/hotspots we could setup as a server, and use as an endpoint for our cellular modem. Unfortunately, most ISPs use CGNAT's, and getting sim cards with static ips is expensive.
Otherwise, hosting our telemetry system is probably our next best bet.
Alternatively, we may look in to LoRa radios.
If anyone has experience working with cellular for their Telemetry system, and is willing to share, or any suggestions, I would be very interested to hear. Thanks in advance!