Linear Technology

We are proud to announce Linear Technology as a Gold Sponsor of CalSol.

Linear Technology are the designers and makers of the boards we are using to monitor our Li-Ion batteries. These boards are essential to both ensuring the safety of the driver and giving us real-time detailed feedback on the state of our batteries. Linear Technology has generously donated these boards, as well as offered advice on how to best use them.

Hexcel – Our New Sponsor!

Impulse’s shell is what gives it shape, and enHexcelsures optimal aerodynamics as we’re racing.  Making this shell as light as possible was crucial to making Impulse competitive, and it’s for that reason that we in CalSol would like to thank Hexcel Corporation for their generous discount of carbon fiber for our car’s shell.

Impulse Unveiling: April 16 at Cal Day

CalSol is proud to announce the unveiling of Impulse, our newest solar race vehicle. It will take place at Cal Day, UC Berkeley’s campus wide open house event.

We invite all CalSol supporters and anyone interested to see what we have been working so hard on.

Hello from the Data Team!

Hello CalSol supporters!

As the Data Lead of Electrical Team, I’d like to give you a little update on some amazing progress we have made recently and take the time to recognize the hardworking members of the team! As the name suggests, the Data Team is primarily responsible for anything data-related on the Electrical Team, although we are also in charge of the radio communication between the cars we are taking to the race. We consist of the Data Logger, Race Strategy and Telemetry Subteams, and we are totally awesome!

ESC’s continued support and E-Week

Without continued support, CalSol would not be able to achieve all that we do. That’s why it’s important to us to recognize our amazing supporters and sponsors! With that in mind, we would like to say a huge thank you to our bronze sponsors, Engineer’s Student Council (ESC)!

CalSol is a member of the ESC (formerly the Engineer’s Joint Council) at Berkeley, an organization dedicated to fostering and nurturing the engineering community at Berkeley. They do so through official events, informal socials and mixers, and also through allocating funding to member groups. Being a member of the ESC means interconnections between student groups, new friendships, and a lot of fun!

Adopt-A-Cell Program

CalSol would like to give everyone an update on our Adopt-A-Cell program!

This program is a fun way for individuals to help support our goals. Our current car, GoldRush, as well as our new car, Impulse, have 6 square metres of solar cells on them, as well as hundreds of batteries. As such, everyone has an opportunity to adopt a solar cell, a solar panel, or a battery.

When CalSol attends large events to showcase our vehicle and talk about the team, please drop by to ask about our program and adopt these cute electrical components of the car!

For more information and a list of current adopters, please check out our Adopt-A-Cell page at!

Telemetry meets Tritium

The test setup for the Tritium motor controller interfacing with the Telemetry board
The Telemetry board and Tritium controller test setup

This Sunday, the Telemetry team met with Rafael to test their new telemetry program with the Tritium motor controller. With the telemetry board connected to the motor controller’s CAN bus, we were able to see all of the packets on our laptop as they were sent, including a graph of the last thirty seconds of data. There are still some bugs to fix and features to implement, but overall we’re quite pleased with the program so far.

Check Us Out

Hello friends of CalSol!

As we work towards the ultimate completion deadline, we also work to keep you informed! There has been lots of amazing progress in the past couple of weeks, and there will only be more! Please check back at our website often for updates on Impulse, WSC, or anything in general.

Optimizing SD Card Writes

The Data Logger Board does not actually use BRAIN as its central processing unit.

Everyone’s heard of black boxes – they are devices that record data in the event that something happens to assist in determining why something happened. Did you know that we have a similar device too – the Datalogger board!

You may be wondering where the BRAIN is, and the answer is, we didn’t use one. Initial testing with SD libraries available on the Internet showed insufficient performance. Additionally, there were concerns about overflowing the MCP2515’s 3-level deep receive buffer while the processor is busy doing SD Card writes. So, we chose the dsPIC33FJ128MC802 chip, which has a higher clock speed, integrated CAN module (with a 32-level deep buffer), and direct memory access to allow SPI transfers in the background. However, a future project would be to try the optimized code on a BRAIN and see if it will yield the necessary performance.

Batch of CalSol PCBs

This Monday, CalSol received a second run of PCBs! We would like to thank Advanced Circuits for their continued generous support of the Impulse project.

The new boards are a revision of the system we successfully prototyped at end of last semester with numerous improvements, bug fixes and additions. We added PCBs for brake lights and turn signals, as well as finalized the design of our custom racking system. This will allow for hot-swapping of PCBs and as well as easy access to the boards for debugging purposes, something CalSol decided would be very useful after past experiences with GoldRush.