MIT’s design wins SpaceX challenge
Hyperloop pod named ‘best overall design,’ recognized for its feasibility
A team of 25 MIT students took the Best Overall Design award in the first stage of SpaceX’s Hyperloop Pod competition this weekend. Their design for a pod that will shuttle between San Francisco and LA at prodigious speeds beat those of over 120 teams at the competition’s Design Weekend, held at Texas A&M University.
Hyperloop is a high-speed transportation system that connects cities with low-pressure tubes housing pods that ride on an air cushion. It was first conceptualized by Elon Musk and SpaceX in 2013 and was motivated by what they see as a need for alternative methods of inter-city transportation.
Instead of building the Hyperloop himself, Musk outsourced it. Last June, he announced a competition to solicit designs for the Hyperloop pod, targeted at university students as well as independent groups.
John Mayo G, project manager of the MIT Hyperloop Team, was drawn to the engineering challenge of the Hyperloop pod and its potential. “We’re developing something that doesn’t even exist yet — there’s nothing to base it off of,” he told The Tech in an interview. “We want to work on new technologies that help shape the world for the better … and Hyperloop is one of those, so of course we were gonna do this competition.”
The team, which has 25 graduate students, collects members from aeronautics, mechanical engineering, electrical engineering. The team even recruited several MBA students from Sloan business school. “It’s almost like a startup,” Mayo said.
Mayo, chief engineer Chris Merian G, and team captain Philippe Kirschen G formed the core leadership of the group. The trio made the driving decisions and came up with ideas that captured what the whole team was thinking. Mayo estimates he spent up to 25 hours a week working on Hyperloop. “Everybody was putting in 15 to 20 hours a week, on top of all their research as graduate students or their classes.”
The MIT squad had four subteams, in addition to business — vehicle dynamics, electronics and software, aerodynamics, and levitation. While the idea for a train in a vacuum tube has been around for a hundred years, the components haven’t been combined until now.
“The defining things of our pod are the aerodynamic shell, the frame, the levitation skis, the suspension, the lateral control modules, and the braking modules — along with the electronics and software, which is the nervous system,” Mayo said.
The basic science behind the levitation system has been tested, but it hasn’t been applied in quite the same way.
“Our levitation skis are a magnet array, which uses the Halbach effect ... The pod is being propelled, and that causes the magnets to move over the track ... and that makes our pod float,” said Mayo.
After the initial propulsion, which can be as low as 5 to 10 meters per second, the pod needs no energy to stay afloat. “The actual act of levitation takes no power,” claimed Mayo. For the final competition, which is an actual test of a half-scale prototype, SpaceX will provide a propulsion system that will rocket the pod off at 240 miles per hour.
“We were focusing on innovating in a couple areas here. We wanted to build a system that could scale up to a full hyperloop system, but we also wanted to be sure that it was feasible enough and small enough that we could build this in the spring semester to test it this summer.”
“If it’s too complex, it’s not buildable in that short amount of time,” Mayo said.
With the speeds that the Hyperloop is expected to reach, braking safely is a huge issue that the team had to tackle. “In the actual competition, the track is only a mile long, so we’re accelerated 2.4Gs. And if you stay at that speed, your run is about 10 seconds, and you need to stop at a similar 2.4Gs to be able to not hit the end of the tube and crash,” said Mayo.
“Another big thing is ... a braking system that is hydraulic and spring-powered,” Mayo said. “It’s able to clamp down on the center rail on the SpaceX track and stop us at 2.4 Gs of deceleration. The hydraulic cylinders hold the brakes open, and then springs clamp it shut. If we have any power loss ... it just clamps shut automatically.”
So, how did they beat out over 120 other teams, representing 27 states and 20 countries?
Mayo notes that they won Best Overall Design, not Most Innovative. “I think the best thing that stood out about our design is the fact that it is feasible and buildable. One of our main focuses was something we could build and physically test in this competition scope.”
They will now begin building a prototype of their pod to be tested this summer on a one-mile track under construction at SpaceX headquarters.
“This week, we’re recapping, we’re looking at our designs, being sure that all the nuts and bolts fit,” said Mayo. “We’re gonna start building some parts, getting a lot parts outsourced and machined ... After that, we will start assembling the pod and testing the individual subsystems — doing things like being sure our brakes apply the correct force, being sure the frame can handle the loads it’ll see, building a small model of the levitation system.”
Ideally, they’d like to put their pod together by the first week of May, and possibly go out the Hyperloop track in California and test it. Twenty-two other teams that qualified from the design stage will also be testing their prototypes.