HTT’s first Hyperloop will use passive levitation

Earlier this week Southern California based start up Hyperloop Transportation Technologies, who's vying with other companies such as Hyperloop One to create the world's first Hyperloop network, a Mach 1.0 "Train in a pod" that was bought back to life from ancient innovations by the famous billionaire polymath Elon Musk, said that the forward motion of its subsonic, people carrying pods will provide the necessary magnetic levitation and lift to help it speed from A to B as a side effect.

Dirk Ahlborn, the CEO and founder of HTT, who was recently caught showing off their latest Hyperloop passenger pod concept, also said that this passive levitation saves energy and “trouble.”

“One of the biggest problems is the need for a high powered track and this [new development] allows us to achieve levitation without having power stations all along the track,” he said.

The passive levitation system that HTT are talking about, which is similar to the Maglev concept, is called Inductrack, and it was first developed in the 1990s at Lawrence Livermore National Labs, in California. It works by lining the bottom of the hyperloop cargo, or passenger pod, depending on the configuration the customer’s bought, with permanent magnets that are placed in a “Halbach Array” configuration that create a magnetic repelling field when they pass over shorted, that is, non-powered, electromagnetic coils on the rail bed or in this case track. And because the effect is passive any power cut would both slow the pod and cause it to settle down on the track.

“The levitating force becomes effective at very low vehicle speeds and remains constant at high speeds,” wrote the inventor, the late Richard F. Post, of Livermore, in a presentation at Stanford University in 2005. An accompanying slide shows that, at least in the non-vacuum packed maglev train envisaged at Livermore, half of the maximum lift force is achieved at a speed of just 1.2 km/h, or just 0.75 mph - about the speed of a racing turtle.

Do turtles race? Mmmm, anyway….

The high-speed HTT system would be tuned differently though, so its pods would levitate only at a higher speed, at about 10 meters per second, Ahlborn says. At that point the pod would be just a centimeter or two above the track but that’s enough.

“We licensed the technology exclusively for HTT,” he said, “Dr. Post passed away a year ago, but we met in the early days, and he was very excited about the technology.”

Meanwhile another California start up Hyperloop One is also developing the Hyperloop but they’re taking a different approach to levitation, using a cushion of air instead but Ahlborn argues that air cushioning would be harder to achieve given the low pressure inner environment of the tube.

Ahlborn also said it would also be less comfortable for the passengers, for instance by making it harder to bank on turns, although, as I sit write this article sitting next to the toilet on the floor of a crowded South West Trains service travelling back from London in sweltering heat as I’m smacked from side to side by the buffeting from the uneven tracks I’d just settle for a Hyperloop running over cobble stones. Ah the comfort.

Ahlborn, you know what to do – I want a ticket when you get your first service up and running, where ever that is - London perhaps? I’m off to rub my bruises and find an ice bath to sit in.