A couple of startup companies set a world aviation record last night.
But they were pretty low-key about it. As I walked into the Future of Flight Aviation Center in Mukilteo, WA, a half hour north of Seattle, I saw little activity. It was after hours, and the hangar-like building was nearly deserted except for the futuristic planes suspended from the ceiling—Burt Rutan’s “Quickie” and a Beechcraft Starship—and part of a Boeing 787 Dreamliner fuselage on the display floor. It was a bit like “Star Wars” meets “Night at the Museum.”
Tom Nugent, the co-founder and president of Kent, WA-based LaserMotive, greeted me and said they were almost ready for showtime. A small team of engineers divided its attention between the back of a command truck and the adjacent trailer that held the laser optics equipment that would make the show possible. Two German guys who hadn’t slept in days (and were still on Munich time) were sprawled out on deck chairs in front of computer monitors like they were playing a video game. One held a remote controller that he used to guide a “quadrocopter”—a small, 1-kilogram, square-shaped flying contraption with blinking lights and four spinning rotors—made by their company, Ascending Technologies.
Jan Stumpf and Michael Achtelik, the co-CEOs of Ascending Technologies, partnered with LaserMotive to perform this feat last night. The goal: to use a laser to power an aircraft in continuous flight for about 12 hours (far longer than its battery would last without recharging, which is only about five minutes). That would be a world record, by a long shot, for the longest free flight of an electric vehicle.
Indeed, this demonstration is a big deal for the future of electric planes, said Barry Smith, the executive director of the Future of Flight facility. Imagine putting a laser on top of every cellular tower, he said, so that certain types of unmanned aerial vehicles (UAVs) would never need to land to recharge or refuel. That could potentially revolutionize communications, surveillance, and security and defense applications. Longer term, it could even impact the long-held dream of powering manned aircraft with electricity instead of jet fuel—though that is very far off.
For now, Nugent says, “The significance is we’re going to show this quadrocopter, and any aerial vehicle [of this size], will be able to fly effectively forever. It’s no longer limited by battery capacity.”
LaserMotive has done smaller flight tests before, but not on a free-flying vehicle like this. The company is best known for winning the $900,000 NASA Power Beaming Challenge last year, in one of the levels of the “Space Elevator Games.” That involved using a laser to power a climbing robot up a cable to a certain height (1 kilometer) at a certain speed (about 9 mph). But lately the company has been targeting UAVs as a big commercial application of its wireless power technology. (The next level of the NASA challenge, which was supposed to happen later this year, is still up in the air, so to speak.)
“Goggles on!” someone shouted, and we all complied. That meant the infrared laser, which puts out about 200 watts of light power, was switching on. The beam was directed using a series of mirrors and optics and shot out the top of the trailer. You couldn’t see it with the naked eye except for a reddish halo on the 50-foot ceiling. At the same time, the quadrocopter lifted off (under its own battery power), guided by Stumpf, and floated up to meet the beam, about 30 feet off the ground (see left).
“Not centered,” Nugent said. Then the computer vision system of LaserMotive’s setup kicked in. Software and cameras aligned with the path of the laser beam tracked the vehicle’s position, and positioned the beam so it hit the photovoltaic cells on the underside of the craft; those solar cells transformed the laser’s energy into electricity to continuously charge the quadrocopter’s battery.
With that, all human corrections fell away, and it was just a drone hovering eerily in space, rotors humming quietly. It swayed a few feet from side to side, and the laser tracked it. It was about 7:40 pm.
This is the boring part, Nugent said. And boring is good. Exciting is bad. For the next 12 hours, if all went well, nothing more would happen. The craft would stay up all night (as would the crew),
