FSGP/ASC2014: We Have Withdrawn

Saturday July 19th was CalSol’s first and last day participating in the Formula Sun Grand Prix 2014 at the Circuit of the Americas. CalSol successfully got Zephyr on the track on Saturday morning. We were able to get a few laps around the track but soon discovered an electrical problem that caused the car to turn itself off after exceeding speeds around 30mph. To provide some context, it was necessary for Zephyr to reliably drive with a speed upwards of 60mph in order for us to take Zephyr on public roads. On the Circuit of the Americas track, one of the very first hurdles was getting past a steep hill before going around the first corner. After a few laps around the track, Zephyr started to cut off its power while climbing the hill.

Zephyr at the starting line of FSGP

Zephyr at the starting line of FSGP

We discovered that the electrical current limit of one of our systems was set too low, thus triggering a safety feature to shut down the car.  This is an anomaly, as we have been able to take the car to speeds upwards of 50mph. We examined every connector, board, wire, and piece of software that we could get our hands on. We were at a constant hustle to get the car running on the track again—but each time it would stall after ten seconds of acceleration. Members frantically ran to and fro along the track with tools, computers, and debuggers.

This went on for six hours. Unfortunately, by the end of the day we had only completed five laps out of the required forty-eight. Though ASC can grant provisional qualification to teams that have a high potential, CalSol decided to withdraw from the race simply because racing a car with an unreliable electrical system on public highways posed a safety risk for the team.

We are very disappointed. We had come out to Texas to race to Minnesota and our FSGP/ASC2014 experience was cut short.

Without a doubt, forfeiting ASC2014 was one of the team’s lowest and the most humbling moments. We learned that the importance of extensive testing wasn’t just some rookie comment, but rather it was an absolute necessity for any team who wants to ensure a reliable vehicle. We experienced first-hand what it meant to push ourselves even when we thought we could not be pushed any further. And the most encouraging part is, we got to interact with the kind and intelligent solar car community who worked across team affiliations to get every car up and running.

In ASC 2012, CalSol reached a respectable 4th place finish on a simple but well-tested vehicle. After ASC 2012, CalSol went great lengths to build a solar vehicle with the most efficient aerodynamics and solar cells, lightest body and chassis, and the most advanced manufacturing techniques that the team had ever undertaken. Despite the measures taken to create the most advanced solar car, we fell short in producing a reliable vehicle.

Like every car, Zephyr succeeded in some aspects and failed in others.

Before packing up, there was one more thing we were able to do in order to help the solar car community. Polytechnique Montréal turned sharply on a tight corner on the track and snapped one of their car’s two Mitsuba motors. The team ingeniously found a way to power the car with a single motor in mere hours, and conditionally qualified for ASC2014. However, being short one motor without a spare was not a comfortable situation for the Montréal team. Since CalSol’s Zephyr uses the same equipment, we let Montréal borrow two Mitsuba motors for the race.

In 2003, CalSol had motor issues and ended up racing with University of Kentucky’s motor. This week we were able to pay that kindness forward. I like to call it solar car karma. Even though we will not be able to race, we are still honored to participate in such an amazing community. We hope that our competitors are able to reach their fullest potential.

CalSol and Montreal collaborating to provide Montreal functional motors for ASC2014

CalSol and Montreal collaborating to provide Montreal functional motors for ASC2014

Montreal's damaged motor

Montreal’s damaged motor

With a great deal of dedication, perseverance, and solar car karma, we are making great progress in solar car innovation. We are using this experience as a stepping-stone for accelerated progress with Zephyr. We’ve identified key issues with over-eager safety systems and are developing a better testing strategy. The best days of this car have yet to be seen, and we are excited to see where we go next.

Min Ju Lee

CalSol team lead

CalSol 2014 team photo

CalSol 2014 team photo

 

Thank you GM for providing us with two Yukons for the race! While Zephyr will not make the trip up to Minnesota, several team members will travel with other teams up north to get the ASC 2014 experience

Thank you GM for providing us with two Yukons for the race! While Zephyr will not make the trip up to Minnesota, several team members will travel with other teams up north to partake in the ASC 2014 racing experience.

FSGP/ASC2014 Update: Scrutineering

Hello everyone! Sorry to keep you in the dark during this past week… if you kept up with our facebook posts, you’d know that this past week was filled with a whole lotta fixing for our team.

The team arrived in Austin, TX with Zephyr that needed a lot of fixing. First of all, Scrutineering was set to start on Monday. Due to our need to fix our defective braking system as described in our previous blog post in addition to an exploded trailer tire, we arrived in Austin on late Monday afternoon to start scrutineering on Tuesday. We added new lights, replaced enclosures, designed temperature sensing system, made new boards, soldered a whole lotta everything, cut here and taped there. We re-did them twice, thrice, four times, as many times until we were ensured that faulty systems were fixed and that we can ensure the driver’s safety.

List of to-do on Wednesday afternoon

List of to-do on Wednesday afternoon

FSGP (Formula Sun Grand Prix) was set to start on Thursday, but we could not get on the track on Thursday because we still had consequential problems that needed to be debugged. In order to qualify for ASC, we must complete 60 laps in 1 day or 90 in two consecutive days. We decided to take our time to ensure that the problems were fixed for good before putting the car and the driver on a track race, to ensure the safety and performance of Zephyr and its driver.

CalSol members busily fixing up Zephyr's mechanical issues

CalSol members busily fixing up Zephyr’s electrical / mechanical issues

Finally on Friday, we were able to get a good to go “green” sticker on all scrutineering stations– solar (modified our array size), body & sizing (installed new lights, modified enclosures, added rear view camera, added paddings), BPS (redesigned and implemented a new temperature sensing system), mechanical (added crumple zones), electrical (added electrical hazard labels), drivers (qualified Ellande, Nick, Aditya, and Aly to be our drivers), and dynamic testing.

Despite the troubles we went through fixing up Zephyr, it performed exquisitely well in dynamic testing. Aditya shocked the team when he zipped through slalom and figure 8 test in record time.

Figure 8 test during Dynamic Scrutineering

Figure 8 test during Dynamic Scrutineering

The team is so excited to get some time on the track race tomorrow. CalSol is team #6– wish us luck & abundant sunshines!

Crazy thunderstorm on Thursday evening + unforeseen fire alarm == rain dance from the teams

Crazy thunderstorm on Thursday evening + unforeseen fire alarm == rain dance from the teams

FSGP/ASC2014: Pre-Departure, Day 0

What a rough week it’s been. The team had planned on departing to Austin, TX on Thursday morning. But as luck would have it, we blew out our braking system on Zephyr while testing on Wednesday evening.

There were several fatal faults in both the design and implementation of the original brakes. ASC regulation states so that we must have a balanced, co-reactive, dual-braking system, in addition to a parking brake. The braking failure was simple– none of the brakes supplied enough braking power, and eventually blew out our master cylinders. However, the problems were complex– not only did we have to find a way to increase the braking power, we had to redesign and manufacture a system that fit in our incredibly cramped space at the foot of the driver. We faced severe time and design limitations. Since a faulty braking system was capable of causing serious damage to the car and the driver, our only option was to postpone our departure and fix the brakes if we wanted a shot at safely racing Zephyr.

Our members Jake, Sam, Tristan, Chris, and Kyle worked day and night, to design and implement a working braking system by Friday afternoon. It was incredibly stressful and tiring for everyone, especially the aforementioned designer / manufacturers of the new braking system. We bought out relevant components off of every nearby auto parts store we could find; worked in two machine shops for 48 consecutive hours; flew out a member to LA on a very short notice to optimize our modified journey from Berkeley to Texas; cancelled all reservations and made new ones; and many of us even left our full-time industry jobs early and commuted to Berkeley to help.

But as teamwork and resilience would have it, we successfully tested a braking test, stopping 65kmph-Zephyr with 5.1 m/s^2 deceleration. With the new brakes, Zephyr is projected to pass scrutineering, but members will continue to make adjustments to improve the braking performance for safety reasons.

Sam literally lived in the Richmond Field Station from Wednesday to Friday, to help design and manufacture the new brakes.

Sam literally lived in the Richmond Field Station from Wednesday to Friday, to help design and manufacture the new brakes.

Jake and his blackened hands!

Jake and his blackened hands!

As stressful as this week was, in retrospect it was good that we identified the problem prior to the race. This is why there is so much emphasis on testing— often times, it is the well-traveled solar car that will win the SunRayce instead of the flashiest solar car loaded with features. Had we encountered this problem during the race, we would have lost a lot of time to troubleshoot this on the road.

The crew is now on the road to Texas. Wish them safe travels!

Pre-departure photo!

Pre-departure photo!

Independence Day and Celebrating the American Solar Challenge!

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!

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!

CalSol PCBs – Thank You, Bay Area Circuits!


Even as CalSol is working hard for the upcoming American Solar Challenge, we continue to get sponsors for our projects. Bay Area Circuits graciously donated to us the service of fabricating our in-house designed circuit boards, which will make up our dashboard, pedals, motor interface, lights, and battery monitoring systems. Thank you for the boards, Bay Area Circuits! We’ll make good use of them.

SAMSUNG

 

Bay Area Circuits