HAWTHORNE, CA—On a sweltering day in Southern California, 20 groups of student engineers gathered on a side street near the SpaceX headquarters to show off the Hyperloop pods that they had spent the better part of a year putting together.
The teams had spent the previous days showing SpaceX engineers their designs and testing them in vacuum chambers and on open-air tracks.
The SpaceX engineers voted on their favorite teams, and the top three were awarded time on the three-quarter-mile low-pressure test track that SpaceX has built next to its headquarters. Delft University of Technology, École Polytechnique Fédérale de Lausanne (EPF), and WARR (a student group within Munich Technical University) were the three teams to win the coveted tube time.
WARR defended its two previous wins again: this time with an average speed of 284 miles per hour and a top speed of 290mph, according to SpaceX announcements during the competition.
The pods had to be self-propelled (no “pusher” vehicle to get them started, per a test in January 2017), and they had to brake safely (no crashing). The objective of this competition was speed; previous competitions have awarded design, innovation, levitation, and other attributes.
Speed has been a limiting factor for commercial Hyperloop companies, too. One startup, Virgin Hyperloop One, has built a test track similar to Tesla’s in the Nevada desert. The fastest time the company has made public has been 194mph. Last August, WARR won SpaceX’s second test track competition with a speed of a little over 200mph. The year-over-year improvement on the team’s pod has been significant, and a SpaceX employee at the competition said that, this year, WARR’s pod was more powerful but actually lighter than its pod last year.
The idea of a Hyperloop—a form of mass transit that would push levitating pods through a low-pressure tube at speeds of 760mph—was made popular by Tesla, SpaceX, and Boring Company CEO Elon Musk when he released a white paper describing his idea. Musk declined to start a Hyperloop company, but SpaceX has sponsored several competitions to get students to design pods.
Musk himself showed up midway through the competition on Sunday. He took the podium, made out of Boring Company bricks, which are formed from mud dredged out of the Los Angeles tunnel that Musk’s tunnel-digging company is building.
“This is like the best opportunity to create something that’s fundamentally a new form of transport,” Musk told the crowd. “What this competition is about is encouraging people to think about new modes of transport.”
“This is something that will encourage people to study engineering, technology, science,” he added. “That was one of the great things about the Apollo—sort of, the Moon program. It got people to say, ‘that’s a great goal.’ It was something for people to get excited about.”
Musk and several members of his family spent the next hour or so meeting with the top-scoring teams. WARR’s winning pod, with eight small motors and custom telemetry and control boards, got special attention from the CEO.
“We are ready for launch! Are you guys ready?” A member of Delft Hyperloop announced to the crowd.
The crowd cheered.
“All right, 5…4…3…2…1!”
Nothing. Sounds of shuffling from the crowd.
“All right, we need to reset some parameters.”
The crowd chuckled.
Ultimately, Delft got its pod to work, but the pod only hit a top speed of 88mph before stopping midway through the tube. The team used a 200kW battery and opted for a system on wheels rather than magnetic levitation. A team member told Ars that they realized that the energy needed to both push the pod up for levitation and forward was equivalent to sending the pod up a 10 percent grade. Although a levitation system would theoretically reduce friction on a relatively short track, there’s not much to be gained from it.
EPFLoop also had a frustrating afternoon. After an hour and a half of system checks in the vacuum-sealed tube, the pod’s communication system stopped working. The tube was opened and the pod was pushed forward, and then the tube was resealed. Still, the communication system wouldn’t work. The competition leaders decided that EPF would have to open the tube again and run the test without a vacuum. But the pod still wouldn’t work. Finally, it was discovered that the battery system had died, so EPFLoop was given 10 minutes to swap out a battery. The pod was then able to run, although it only hit 53 miles per hour, according to the official timers run by SpaceX.
Texas Guadaloop had a fun Hyperloop pod design. It was one of the few teams that designed its pod with air bearings—as Elon Musk had specified in his original white paper on the Hyperloop. Team member Patryk Radyjowski told Ars that the team partnered with a company called Airfloat, which makes wide air bearings for moving heavy objects, like locomotives, slowly across a warehouse floor. The team’s objective has been to optimize the pod design to use the air bearings at higher speeds.
Radyjowski said that part of the reason most other student teams design pods with magnetic levitation rather than air bearings is that air bearings require high-pressure air tanks, which make running the pod at high speed more dangerous. Texas Guadaloop outfitted its prototype pod with two scuba tanks at 4,500psi.
“One of the things I’m proud of is how simplified this is,” Radyjowski said, pointing to his pod’s central board. He noted that the first iteration of the pod was three times as large as the current one.
Another team, Hyperloop UPV (short for Universitat Politècnica de València), showed off its hyper-custom pod at the competition. The team members spent a considerable amount of time designing their own battery management system for a couple of stacks of lithium polymer batteries on the pod. A team member admitted that, by the end of the project, Hyperloop UPV had spent far more time and money trying to self-design its battery management system than it would have spent if it had purchased an existing battery management system, but the point was getting the experience.
DiggerLoop, the team from the Colorado School of Mines, had a giant central wheel attached to an electric motor that powered the pod forward, with an array of 10 50-volt batteries that connect to create a 500-volt, 500-amp system. (Full disclosure, I’m currently attending a Colorado School of Mines master’s program.)
University of Washington came in fourth, with a pod that used polyurethane wheels and a cold-gas propulsion system. It was the only team to use such a propulsion system, and the SpaceX engineers commended the team at the end of the competition for being able to prove that the propulsion system would be safe to run in the low-pressure tube. The pod weighed about 200lbs and had an air-actuated braking system.
Although gains from these pod races are usually incremental, the point is not to make a perfect Hyperloop pod—or to prove the technical possibility of a Hyperloop—but to show off how talented the world’s next generation of engineers is. With that in mind, Sunday was very successful indeed.