Case Study: University of Toronto Blue Sky Solar RacingOthers
Since 1996 the University of Toronto Blue Sky Solar Racing team has been designing, building, and racing solar powered cars. Over their 20-year history, the team has built nine unique cars and competed in the bi-annual Bridgestone World Solar Challenge six times. The team, consisting entirely of undergraduate students, strives for top efficiency for the 1,877-mile (3,000+ km) race across Australia’s Outback. An integral part of the car is the carbon fiber aerobody, which contains all the internal components of the car, and is essential to reducing the power consumption of the car by keeping drag to an absolute minimum. The team is constantly striving for a smoother and more aerodynamic outer shell to guide the team to the finish line.
For most of their history, the team has utilized the industry standard plug-mold process to construct the aerobody. This process gives the team the required control and finish needed for the high-quality work needed to maximize the aerodynamic stability during the race. The early models of solar cars mainly used wood as a support structure for a Renshape polyurethane foam mold. Recently the team made the switch to a 100% wood plug for the last two generations of cars, as it is more easily workable and can more consistently provide the desired results.
The team starts by designing the plug from which the mold will be made, using Computer-Aided Design (CAD) software. Once the mold is designed, the team hand cuts most of the pieces and sends the more complex ones to be professionally machined. When the roughly 200 pieces of medium density fiberboard (MDF) engineered wood are all cut, the team then stacks them together and sends the assembled plug to be precision-machined using Computer Numerical Control (CNC) processes to achieve the precise aerobody pattern.
The finished product is a positive plug that is then used to create a fiberglass negative mold. This fiberglass is used as a contact layer for the carbon fiber sheets used for the actual body of the car.
The team chose to use MDF engineered wood because of its easy machinability and the high surface quality it can yield. When the plug is made from MDF, the students primarily use the tools at their on-campus workshop to cut and shape it, making the machining process more efficient. Once resin is applied, the high-quality MDF wood also yields a superior surface finish compared to other materials.
For the Blue Sky team to conduct the plug and mold process, they require lots of MDF panels. In addition, a large amount of plywood is required throughout the process for the structures that support the plug and mold.
When construction started on Polaris, the 9th generation vehicle, ARAUCO North America donated both the MDF panels, as well as the plywood used to support the molds. The team at ARAUCO, including a few University of Toronto Alumni, embraced the Blue Sky Team and became great fans, as they prepared for the highly-anticipated Bridgestone World Solar Challenge, held in Australia October 8-15, 2017.
Update: 2017 Bridgestone World Solar Challenge Results
The university of Toronto’s Blue Sky Solar Racing team crossed the Official Finish Line in Victoria Square, Adelaide, on October 14th, finishing 11th in a very adventurous race – even withstanding the worst thunderstorm in the Outback in 20 years. Edged out by the Nuon Solar team, from The Netherlands, who claimed their seventh title in the Bridgestone World Solar Challenge, the Blue Sky Racing team vows to return in 2019.
The Blue Sky Solar Racing team at the unveiling ceremony of Polaris, the 9th generation solar car