Since 1987, solar powered cars have been competing to cross Australia top to bottom in the World Solar Challenge. In this year’s event, engineering students from Halmstad have been assisted by Automotive Components Floby AB (AC Floby) in producing a specially adapted brake disc.
“We want to encourage students to get involved in future technology – and of course it sounded like a really exciting project,” says Anders Johansson, Design Engineer at AC Floby.
13 October sees the start of this year’s Bridgestone World Solar Challenge – a 3,000-kilometre car race across Australia, from Darwin in the north to Adelaide in the south. As the name suggests, it’s not only the long distance that distinguishes the race from conventional motor sports; the cars are only allowed to use the sun as their energy source. One of the competitors is HUST, the Halmstad University Solar Team, which comprises 27 development engineering students from Halmstad University in Sweden. They have spent two years developing the solar-powered car, which is already in Darwin. One of the biggest challenges was making the car as lightweight as possible, without compromising on safety. The students therefore turned to AC Floby and asked for help to develop a brake disc that did not weigh the car down unnecessarily, while also offering complete reliability in any situation.
“Many of the other contestants use bicycle brakes in their cars. They’ll probably work, but we wanted a brake system we can really rely on if anything should happen, like a kangaroo jumping out in front of us in the middle of the desert. Our car may not be the best looking one in the race, but I’m convinced it’s the most reliable,” says Adam Jisland, Project Manager for HUST.
Extremely lightweight brake disc
The brake disc in the HUST car is an evolution of AC Floby’s newly launched SiCa Light, developed to meet future needs for sustainability – both in terms of environmental impact and product life. With a basic matrix in aluminium reinforced with silicon carbides, the brake disc is extremely strong yet also very light. SiCa Light weights 30–50 per cent less than an equivalent conventional cast-iron brake disc, depending on the application.
. Since the HUST solar-powered car is far lighter than normal cars and will not be driven at such high speeds, the specially designed brake disc could be made very thin. Following comprehensive refinement, it ended up weighing just 600 grams. When the students tested the car before it was shipped to Australia the brake system had not been fully bled, but even then the brakes worked better than expected.
“They engaged just the way we wanted, so we can rest assured that the brake disc will bring the car to a stop. Having said that, we’re hoping to stop as little as possible. The race lasts seven days, but we’re hoping to reach the finish in five or six,” Adam Jisland concludes.