Mid-Summer Update – Powering Up and Strapping In for FSGP 2015!

Viswanath Chatterjee // // No Comments

It’s just three weeks until the Formula Sun Gran Prix at the Circuit of the Americas race track in Austin, Texas, and the CalSol team is looking forward to driving with and competing against the rest of the solar car community! We haven’t posted in a while, and there haven’t been core design changes lately, but the excellent state of this car and this team has us feeling optimistic for FSGP. Addressing potential bugs (mechanical, electrical, and code), implementing optimizations to squeeze out every watt we can, and testing the systems has kept us plenty busy lately, so check out some photos of the work!

 

Tidying up the wires and securing connections in the all-important battery box

Tidying up the wires and securing connections in the all-important battery box

Reinstalling sturdy enclosures to hold up and protect the various boards on the underside of the top shell

Reinstalling sturdy enclosures to hold up and protect the various boards on the underside of the top shell

Revising boards to include additional safeties (gotta love capacitors) and power routing optimizations

Revising boards to include additional safeties (gotta love capacitors) and power routing optimizations. Shout out to Bay Area Circuits for all their help with the PCB’s!

Building the solar array for an off-site "electrical test bed": a scaled-down version of the electrical system!

Building the solar array for an off-site “electrical test bed”: a scaled-down version of the electrical system!

And with a mini solar array comes an equally adorable mini battery box

And with a mini solar array comes an equally adorable mini battery box

Mechanical folks contemplating life. CalSol is life.

Mechanical folks contemplating life. CalSol is life.

Installing an improved hinged fairing door mechanism

Installing an improved hinged fairing door mechanism with a carbon-fiber axle

Road-testing Zephyr, which now has a few hundred miles on it, brings us admirers of all ages

Road-testing Zephyr, which now has a few hundred miles on it, brings us admirers of all ages

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We’ll be sending out updates during the race, or post another photo gallery at the very least. See you all then!

The Team’s Snapshots from FSGP 2014!

Viswanath Chatterjee // // No Comments

Although everything couldn’t quite come together this time, the team certainly had a memorable experience these past two weeks. The mechanical team put in a truly incredible amount of work into Zephyr (I am personally on the electrical team, so I think I can say this without bragging, haha). So much of the car you see is handmade, from the sleek carbon-fiber shell to the welded aluminum chassis, with little tolerance and deviation from the models. Even the current electrical issues are only a temporary speed bump for ¬†Zephyr; we simply didn’t have the resources and time to fix them when they arose unexpectedly last Friday. I am still very proud to be part of this team, and know how much work went into designing and building Zephyr. There will be races ahead for our latest vehicle, but until then, check out some photos from FSGP 2014!

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Zephyr and friends, ready to rayce (despite the clouds)!

The truck space was heavily optimized, significantly reducing mileage

The truck space was heavily optimized, significantly reducing mileage

resizing blargh

Getting ready to load Zephyr into the trailer, departing from Berkeley at sunset

The rather picturesque spot in the Mojave Desert where the trailer's wheel blew out

The rather picturesque spot in the Mojave Desert where the trailer’s wheel blew out

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Switching out the chewed up wheel and what remains of the tire rubber

Sunset in the desert with CalSol

Zephyr being rolled out at the Circuit of the America, not yet adorned with decals

Demonstrating the suspension system to the inspectors, naturally by standing on it

Demonstrating the suspension system to the inspectors, naturally by standing on it

You could say we all had a few bugs in our cars

You could say we all had a few bugs in our cars

 

A lot of mechanical fine-tuning and touch-ups were done at FSGP, to say the least

A lot of mechanical fine-tuning and touch-ups were done at FSGP, to say the least

 

The glorious prototype telemetry box deserved a spot here

The glorious prototype telemetry box deserved a spot here

 

Securing temperature sensors inside the battery box

Securing temperature sensors inside the battery box

 

Zephyr's drivers studying the race track via simulation, mentally noting the turns and optimal speeds

Zephyr’s drivers studying the race track via simulation, mentally noting the turns and optimal speeds

 

Adjusting the rear-view camera placement

Adjusting the rear-view camera placement

 

Doing some late-night work on the power distribution box, the night of a record thunderstorm

Doing some late-night work on the power distribution box, the night of a record thunderstorm

Zephyr showing off its handling during dynamic scrutineering, with an especially impressive slalom run

Zephyr showing off its handling during dynamic scrutineering, with an especially impressive slalom run

We hope you’ll continue to join us in Zephyr’s future adventures, and see you next time!

 

 

 

 

Independence Day and Celebrating the American Solar Challenge!

Viswanath Chatterjee // // No Comments

With only days until the race, CalSol has been working in overdrive, and the results are showing in the impressive performance of Zephyr. The team is working all hours of the day and night testing the various systems such as the power distribution box contactors, implementing final touches like the dashboard,  and checking off end-stage features such as the regulations-compliant DMV license (Zephyr will be sharing the highways with everyone else during the cross-country race).

On July 4th, teammates gathered at the Richmond Field Station to honor the American tradition of charcoal barbecues and fireworks (heard over the San Francisco Bay), as well as the CalSol tradition of working past midnight wiring bypass diodes, modifying wheel fairing doors, and fixing remaining bugs and issues with the vehicle. In the past few weeks, tremendous progress has been made as the vehicle materialized from its myriad components. New members have made names for themselves through the long hours, experienced members have kept the team on track, and alumni have taken time out of their already busy schedules to help out with their expertise.

The team working on all three of mechanical components, electrical boards and connectors, and controller board code! The bottom shell and chassis is on the left, and the top shell and solar array is on the right.

The team working on all three of mechanical components, electrical boards and connectors, and controller code! The bottom shell and chassis is on the left, and the top shell and solar array is on the right.

It’s likely that this will be the last update before the race, as just the logistics and finishing touches are being figured out now. The team is very happy with Zephyr, and we look forward to meeting our competitors soon!

Electrical Team Making Progress and Giving Thanks!

Viswanath Chatterjee // // No Comments
The Hackerspace has been kept heavily utilized by CalSol lately!

The Hackerspace has been kept heavily utilized by CalSol lately!

The electrical team has been making good headway lately, with new, experienced, and alumni members all working to finish the assembly, testing, and troubleshooting of Zephyr’s electrical system.

The HCI (Human Control Interface) sub-systems are able to communicate among themselves over the CAN bus, which stands for Controller Area Network and allows for communication without a central computer. These sub-systems include the dashboard, accelerator and brake, steering wheel and side panel, and the two motor controller controller (which controls the motor controller, and is dubbed the MC^2). The controllers are working, and the motors are able to spin.

Regarding the solar cells, the solar array is coming together, with the team ready to finish placing the cells. The MPPT’s (Maximum Power Point Trackers, which keep the solar array at an optimal power output by manipulating on the I-V curve) are able to communicate over CAN as well.

Additionally, the two power hubs (which distribute power to the various electrical systems, which need to be kept on lines of separate voltages) are ready, and the BMS (Battery Management System) seems to be operational. All the electrical boards have been soldered, populated with components, and tested. The battery box has been built, and the fuses, connectors, and peripherals are being mounted.

The HCI system, including the LCD readout for the driver

The HCI system, including the LCD readout for the driver

The little nickel strip on the bottom of the module with the hole punched out is used to help measure voltage across the battery banks

The little nickel strip on the bottom of the module with the hole punched out is used to help measure voltage across the battery banks

Careful alignment of the solar array is required, since the indentations on the carbon fiber shell allow for little tolerance

Careful alignment of the solar array is required, since the indentations on the carbon fiber shell allow for little tolerance

We couldn’t have done this without the financial and technical support of our sponsors:

Advanced Circuits, for producing many of Zephyr’s PCB’s!

Bay Area Circuits, also for producing many of Zephyr’s PCB’s!

LEMO, for donating connectors!

Phoenix Contact, also for donating connectors!

Linear Technology, for giving LT boards and chips, providing monetary donations, as well as technical support and guidance!

 

 

 

Thanks for catching up with us, and see you soon!

DC/DC Converter – Thanks, Vicor!

Viswanath Chatterjee // // No Comments

It’s been a while since our last blog update, but the intrepid CalSol crew has definitely been busy. Both Zephyr’s mechanical and electrical systems are nearing completion, and with all the work being put into making this our greatest vehicle yet, we’ve got plenty to report with new updates!

We would like to thank Vicor Corporation for their generous donation of the DC/DC converter and its appropriate mounting and connection accessories, as well as the assistance of their applications engineers in selecting the components! But first, what does a DC/DC converter do? (more…)