The build cycle, as always, had ups and downs but we came out of the process with a car we were happy with and that performed competitively. One of the things we were most proud of was the car’s overall reliability thanks to the thorough engineering. The majority of our car was constructed in-house, which gave our team members a very good understanding of its capabilities and points of failure. Adding to this, we constructed our own array, doing both the modeling and physical assembly of the cells (including encapsulation). The skills learned were definitely important and came in handy when repairs were needed after a crash during testing.
Overall, Arctan was the quickest and most efficient car we’ve ever built. We finished 6th overall in the 2015 World Solar Challenge and even though we placed behind Luminos, we cut our time behind the winning team in half – a indication of the improvement from teams across the board.
We also continued to use the highly efficient and proprietary motors we had from Luminos and designed and built our own array in-house. A change in the encapsulation stack produced a visibly different finish of the solar cells. Luminos’ topshell was glossy while Arctan’s was more satin-like. We used more efficient solar cells and improved on our encapsulation methods as well.
The car had a total, unoccupied weight of 212.7kg, and ran on a 5kw hr battery. On average, it used about the same amount of energy required to power a toaster!
Prior to the race, during testing, strong sidewinds challenged the catamaran design. The car went in to an oscillating pattern before veering off the road, and sustaining damage to the array. Luckily, the team was able to make repairs before the actual race.
From a technical point of view, this required the replacement of sections of the array making it essential that we had constructed our array in-house. From a safety perspective, this led to even more thorough driver safety precautions, with all drivers taking an additional course on handing the car in the sometimes-windy conditions of of the outback. Moving forward, we maintained increased contact with the driver and relied on additional safety courses to allow the drivers to make even better judgments while driving.
The race itself went relatively smoothly, despite on the second day on of the accompanying vehicles driving off with the keys for the scout vehicles. A rolled up safety vest (for visibility) wrapped around the keys tossed out to the side of the highway and a few hundred meters of breathless running up the highway by another team member, and everyone was good to go. In another instance, we weren’t able to get gas at a control stop and all the support vehicles nearly ran out of gas. For a period of time there was no air conditioning, and one team member radioed about how nice it would be if the cars were solar powered instead. As these examples show, we took the race, safety of our team members, and proper protocol seriously, but still maintained a good humor that allowed for positive problem solving in tense situations.
The Team Assessing the Damage
Team Lead - Guillermo Gomez
Array Lead - Matthew Matera
Business/Logistics Lead - Rachel Abril
Financial Officer - Kelsey Josund
Co-Mechanical Lead - Anna Olson
Co-Mechanical Lead - Aravind Arun
Engineering Lead - Darren Chen
Composites Lead - Jamie Goldfield
Embedded Code Team Lead - Eric Thong
“Participating in the Stanford Solar Car Project was a wonderful experience for me that really taught me how to make an engineering design function in the real world in a way that classes never could. For me this was one of the best ways to learn these hands-on lessons that I am still using today.”
– JB Straubel, Chief Technical Officer, Tesla Motors, & SSCP Alumnus
