This post was written by Continuum Mechanical Engineer, Doug Lambert.
The first meeting I remember for Continuum was a small discussion at the end of August in 2005. I had just won a national championship with Momentum and other students were just starting to arrive on campus before we would leave for Australia. The attitude of the team in those days was that our main race was NASC and then if we were able we would race in WSC after, and though our hopes would rise as the race got nearer we knew we didn’t really have a chance to win. Team Mechanical, the mechanical engineers on Momentum’s race crew, had been discussing what we could do to improve our chances in the upcoming race and concluded that mechanically we couldn’t do much to win the race, that mechanical parts could only make us lose by being unreliable or by being too heavy. The way for us on Team Mechanical to influence the race would be to take on more challenging designs so we could allow aerodynamics to be better. It was too late for that to happen for Momentum in WSC, but we figured the next car could take advantage when we got back.
In that first meeting, Team Mechanical and Chris Churchill decided there would be an aerodynamic benefit to having a 3-wheeled car with the single wheel in the front, and that we would be up to designing suspension and steering that could allow it to work. Chris was a graduate student that had helped us the previous school year with design work and was a previous team leader for Principia’s solar car team, so when we asked him to help get the team going in the right direction while we were in Australia he nearly finished building a test vehicle by the time we got back.
I think the real significance of Continuum is that it was a transition point in the team’s history. As I mentioned earlier, the attitude of the previous project was to win NASC and then maybe compete in WSC if possible. As far as I’m aware that had always been the philosophy of the team, which made Continuum the first project to focus on winning a world championship from its beginning. The winner of WSC 2005, Nuna, had averaged over 100 kph, and so we figured we had to design a car to do 110 kph in order to have a shot of winning WSC 2007. In order to pursue that goal we changed every major system on the car, not just the aero and mechanical. We replaced our old motor and motor controlled with newer ones that would be a few percent more efficient. We replaced the power trackers for the array to try to optimize a little more. The battery pack was a different chemistry than we had used to try to increase our capacity.
The other major transition was on the kind of design cycle we used, and it wasn’t a change we had planned on making. Over the summer of 2006 we had a finished aero design and were looking for a sponsor to make the body molds for us. Luckily, we were slow to find one, because WSC announced major regulation changes that would have put our car in a non-competitive exhibition class. That same summer rumors started spreading that NASC would cancel the race in 2007 due to funding problems. Our project cycle suddenly changed from having two years to design, build, and test then racing in July and October of the same year to a compressed one-year design and then race every year.
We had some growing pains, to put it lightly, adapting to the quicker design cycle. It seems like the more recent teams have managed much better than we did that first year. When I was the engineering director in the first half of 2007, I sometimes wondered whether we would have a fully tested car to ship to Australia or if the first time the car drove would be on the left side of the road. The new regulations did open a door for us, though. They allowed more surface area than array area and removed regulations that prohibited mirrors and lenses from being used to focus light. We took advantage to create the concentrator system on Continuum, which was ambitious but created even more work and pushed us later. Even with the lack of extensive testing and underdeveloped strategy that caused, Continuum had a real chance of winning the first world championship for an American student team. I still think we would have won if not for our crash, but it’s impossible to know for sure.
Trying to start on the next project while modifying Continuum to race NASC in2008 was another new experience we struggled with. The initial plan was to kind of divide the team and run both projects in parallel, but it seemed like the focus was all on preparing for the race and not designing a new car. As a result, Infinium was forced into something more along the one-year design schedule Continuum had rather than the longer schedule allowed on earlier programs. On the bright side, racing Continuum in NASC allowed new team members to get experience quickly and carry it through to the design of the next car.
Is it possible to consider the past 5 years and 3 cars an era? If so, I’d like to say that the significance of Continuum was in creating the modern era of the team. We changed the ambitions of the team, and the process of getting there. Frequently we suffered from those changes, but the end result was a good car and a stronger team to carry on our legacy. Now all we need is a car to finally fulfill our goal of winning a world championship. Hopefully we won’t have to wait past October 19.