TECHNOLOGY

Competing to Create Elon Musk's Hyperloop

As the world tries to cut back on emissions, new means of transport are essential.
25 August, 2016
Nearly everyone in the developed world knows what it means to be stuck in traffic on a congested roadway.
Not everyone in the world is Elon Musk, the high-impact thinker behind the SpaceX competitions whose annoying commute inspired a global competition to design a fast, environmentally friendly solution for train travel instead.

That's how the ambitious Hyperloop project was born, with funding partners and technology teams all over the world invested in a new vision of rail that relies on passive magnetic levitation. The race to bring Hyperloop to market includes places like Slovakia, where the Musk-backed American Hyperloop Transportation Technologies team has an agreement to place its end product in several cities; to the European partners in France, Germany and Switzerland at Hyperloop One – the California business that's built a test track for trains that float above the rails in pods that may travel at up to 700 mph (1,127 km/h).
Image: Wikipedia
Hyperloop has attracted the attention of university teams, too, and it was the design submitted by the Massachusetts Institute of Technology that took the top spot in Musk's SpaceX train competition.

The task of the SpaceX contestants was to create a vehicle concept within the known technology framework of the Hyperloop, taking the train one step closer to reality. The first iteration of the MIT design, submitted last year by a multidisciplinary team of 28 students from aeronautics, mechanical engineering, electrical engineering, and business, delivered a passenger pod that relies on two arrays of 20 neodymium magnets that hold the pod just 15 mm above the track at cruising speed.
The pod is designed with aluminium support rails and mounting brackets in a ladder frame, while the pod shell is composed of woven carbon fiber. The braking system uses magnets. The Hyperloop's power of levitation is based on an understanding of the Halbach array, a special configuration of magnets that "bends" the power of the magnetic field. It applies the same principle invented by the late physicist Klaus Halbach, originally used to help focus the beams used in particle accelerators and achieve otherwise unattainable speeds, to create the Hyperloop's propulsion along and above the track.
An existing model called Inductrack uses the magnets to induce currents in track circuits that, as the train moves along, repel the magnetic arrays on the train and cause the levitation lift. The magnets don't require power to create their magnetic field, but a source is used when the train starts moving so it can overcome the existing aerodynamic drag to achieve its levitation state. With magnets this powerful, one of many questions is how passengers with pacemakers, for example, will be protected from its forces.

Other questions, according to the U.S. Department of Energy, center on how to use the technology in other applications. They include space exploration, to reduce fuel costs at rocket liftoff, or safe mining cars that don't produce sparks. One intriguing possibility is the potential for intercity freight shipping that's based on packages levitating in underground tubes, much the way drive-in bank tubes still look.

But for the MIT team – and other entities focused on Musk's concept – the train itself takes priority. The MIT passenger pod, hovering above its aluminium track, continues its design journey as scientists refine its performance when speeds change, vibrations occur, and countless other factors make themselves felt. They are also working to make the concept affordable in ways that deliver real-world rail improvements to cities.
Banner image: Numerama