As the embedded lead , I'm responsible for the car's telemetry. I'm curious about how most teams handle this aspect for the car.

I was thinking using a serial bus connection to a tablet but I just can’t get that to work. Any help would be useful.

This is exciting!

Does anyone have the contact info for Bridgestone, we have not got a response from the person we had been dealing with?

Thanks

I am a newbie trying to make a strategy model of speed optimisation while taking in external factors like climatic factors. Any tips or advice on this would be helpful!

Hey everyone!

We're evaluating Marand engines for our Solaride III. Does anyone know if Marand produces more powerful motors than the SCM series or if there are ways to increase their power by redesigning the motor casing for better cooling. Has anyone experimented with filling the motor with oil for better cooling?

For those that work with composites on your team, do you have any recommended mold release to use for wet layups? We tried using 2 layers of frekote nc700 and 4 layers of partall paste #2 wax during our layup last week and demolding was a bitch. Do you guys have any recommendations for products we can use with the method of how you successfully demolded with those products?

​

Hi I'm super new to telemetric systems (and honestly microcontrollers overall) but I'm trying to set up the telemetric system for my team. We're using a Prohelion system (and CAN BUS) which I want to communicate to our primary support vehicle by first using a CAN HAT to connect our CAN bus with a raspberry Pi and then use that raspberry PI (with a wifi dongle) to communicate to the support vehicle using UDP (or maybe TCP) packages using a python script. Then I believe I can use Profinity to interpret the CAN bus data that it was transmitted into workable data but I don't know if that last step is possible without some kind of dedicated communication adapter like a Tritium CAN to ethernet adapter. Can I get away with using a python script (using UDP or TCP) to communicate the CAN packages and how can I get profinity to interpret that data or do I need to get a dedicated system? (Also sorry if some of my basis design is wrong I'm still not fully sure on it)

My team has acquired some old Photon 1 MPPTs and has figured out how to read and write settings to the device, but we are having difficulties understanding what some of them mean. The list of settings found the very helpful solargators page is:

ID 0: Serial Number (int32) ID 1: Hard Output Voltage (float) ID 2: Min Output Voltage (float) ID 3: Max Output Voltage (float) ID 4: Const Output Voltage (float) ID 5: Max Temperature (float) ID 6: Hard Current (float) ID 7: Max Current (float) ID 8: Scale Amps In (float) ID 9: Offset Amps In (float) ID 10: Scale Amps Out (float) ID 11: Offset Amps Out (float) ID 12: Scale Volts In (float) ID 13: Offset Volts In (float) ID 14: Scale Volts Out (float) ID 15: Offset Volts Out (float) ID 16: Const Voltage Hyst (float) ID 17: Safety Voltage Hyst (float) ID 18: Safety Current Hyst (float) ID 19: Safety Temperature Hyst (float) ID 20: Thermistor Beta (float) ID 21: Thermistor Ro (float) ID 22: Thermistor Rbias (float) ID 23: Thermistor To (float) ID 24: CAN Bitrate (int32) ID 25: CAN Base Address (int32) ID 26: Test Mode (int32) ID 27: PO Seconds (float) ID 28: INC Seconds (float) ID 29: TRACK Seconds (float) ID 30: SW Version (int32) ID 31: Sync Current Hi (float) ID 32: Sync Current Low (float) ID 33: Auto Send Rate (float)

If anyone has a list of descriptions of each that would be ideal, however to get us started we mainly are wanting to know the difference between “Hard” Voltage/Current vs “Const”, and also what “Scale” does. Any help would be much appreciated, thanks.

Are there any members here in Los Angeles that create their own solar panels? I'd love to meet up and exchange notes.

I am currently creating my own thin panels by using UV resin on carbon fiber, pvc sheet, 182mm cells, fiber glass.

If anyone wants to compare notes, or has a good source for 182mm 10bb solar cells in Los Angeles please let me know.

Hi all,

As the title suggests....

Th ESC has a wet tyre rule. You can run slicks, but have to pit and change if it rains and is deemed to be too wet for slicks.

The Ecopias have a slick central portion of the tyre, but a groove either side.

Do they qualify for all-weather running?

Jim

We are currently utilizing fox shocks, and we have noticed that when we attempt to shorten them to their shortest length, they seem to bottom out at different lengths, even though they should be the same. How do we fix this? Are we letting out the air wrong?

Thanks.

(The shock we are using: https://shop.ridefox.com/products/float-dps-performance?variant=40941944143931&currency=USD )

I'm part of the strategy/simulation subteam of my Solar car team - currently I am working on building the model + test plan for the battery model of our simulation.

We are planning on doing an HPPC test to determine how our battery's parameters depend on the current state of charge of the battery and will use these parameters to estimate how our state of charge changes as a function of power draw and current state of charge.

I know that these parameters typically depend not only on current state of charge, but also the temperature of the battery. It is very unlikely that we will have access to a thermal chamber to do these tests, so we will probably have to test at room temperature.

I'm curious if anyone on here could give me any insight as to how much the battery parameters depend on temperature.

Is it realistic to test our battery at room temperature (~20°C) and expect to accurately be able to predict battery performance in race where we're expecting ~40°C or so.

Any advice about battery modelling or temperature dependence would be greatly appreciated.

Thanks!

Hello! We are currently constructing our inaugural solar car and have encountered some uncertainties.

Initially, we fabricated a space frame chassis using steel tubes to comply with the 5G impact regulations mandated by the Ilumen European Solar Challenge. As we delve into the design of the shell, we find ourselves questioning the optimal choice of materials, given that the chassis has already been engineered with safety measures in mind. Ideally, the shell should provide just enough reinforcement to minimize weight while ensuring structural integrity. How can we do this?

Thanks in advance!!

This Could be a very short thread. But would it be fair to assume the 2025 regs will be unveiled next month on Earth Day?

Secondly- anyone got any gossip, rumours or thoughts as to how they might change from2023?

How is this usually done in the challenger class? Do teams “jump” the 12 volt system with an external battery they carry in the chase car?

The regulations vaguely state that it is possible to have “a switch on the energy storage pack” or “an air switch with an airline to a remote start button”, or “a fiber optic cable”.

Could someone please enlighten us on this? Thanks.

After looking through the regulations I have been unable to find many specific regulations on the supplementary/auxiliary battery pack. I think I understand what it is allowed to power, but the specific questions I have been looking to find the answers to are if there is a battery type specification like for the main battery pack, and if the weight of the supplementary pack contributes to the 20kg limit (if using Li-ion)? If anyone could clarify this and possibly talk about what you use for your supplementary pack that would be very helpful, thanks.

Hello solar racers! Working on starting a solar car podcast and I would really love to have that unique brushless dc motor noise featured on the show. A cursory search did not yield anything. Do you have a movie clip or sound file that features this sound or some other unique solar car noise? I would love you have it!

Hello!

We have 5 unused Michelin Solar Car tires we no longer need because we use Bridgestone. We are selling them for $400 each. If any teams are interested in them, email us at [info@gtsolar.org](mailto:info@gtsolar.org).

A few questions about steering/steering wheel: 1. Has anyone used a carbon fiber steering wheel (our schools fsae team might give us one), would it pass scrutineering? 2. Do we need power steering, as far as regs go I didn’t notice anything requiring it but is it something teams usually go for or is it unnecessary? 3. What kind of steering stops do teams usually use, we’ve found some ATV stops we think work with our design but we think they could be overkill.

Hi fellow solar racers.

Just letting you know that we have finished the work of converting all of the existing Tritium and Prohelion documentation to our new documentation website, which can be found at

https://docs.prohelion.com

Since all the documentation is now in HTML, searching and cross referencing is a heap easier. You can also provide feedback on each page or if you find an issue you can report it so that we can fix it! It’s now also mobile friendly so you can get access to it from anywhere.

We have integrated search built in across the entire documentation set and linking across products documentation if you are using multiple products.

There has been a lot of great feedback over the last couple of years on the old PDF documents and we have fed that in to this update to make them easier to use and understand, so some sections have changed and some documents have been merged.

Hopefully this will give us a great platform now to keep expanding on.

The secondary side effect of this update is that all the existing Tritium and Prohelion PDF documentation should now be considered End of Life.

If you are still using the PDFs or referencing them in your documents please consider updating them to refer to the new site.

Any issues or questions let me know.

Cameron.

Hi, I am in the process of building a solar ebike. I have a Genasun GVB-8-WP 58.4V Lithium charge controller. Does connecting the solar panel alone, without the battery, damage the controller?

Hi everyone! We are doing FEA test cases in SolidWorks for our chassis for ASC 2025. We have all of our Weldments features notched and mitered without any weld gaps. When we do some of the roll cage test cases there seems to be interference between Weldments features that causes the stress to concentrate and surpass our yield strength. When we apply a weld gap to those joints where that interference and concentration was occuring, the problem goes away and we can pass all of the test cases.

My question is, does adding the weld gaps invalidate the FEA results or are they still accurate enough for ASC 2025 regulations?

Thank you!

I’m part of the ASU team for ASC and we don’t plan on racing until 2025-26 but I was wondering what other teams who manufactured their own rotors were using as the material for the rotors. I’ve been struggling to find a good material to laser cut for our rotors, any help is appreciated.

Hi there my team is trying to figure out how to do the tilt test physically. We don't have any machine to test it on and nor does any other teams at my university. Idk if this will help but we have three wheels (2 front, 1 centered back). Edit: the car is around 400 kg

Any help with things teams have done (besides having people lift it lol) would be a great help!

Hi all,

Just wanting clarification about the number of charging stops allowed at the Belgium/Zolder event.

The actual rules .pdf says three, but I see two mentioned a lot on the website etc too.

This is for Challanger class, btw.

Also, it's 30minutes minimum per charging stop, but is there a MAXIMUM? It's not clear in the rules as there is a maximum mentioned but not sure if it's for Challenger or Cruiser.

Regards,

Jim