Powered only by lasers, hovering drone flies for twelve hours straight

Ground-based lasers could soon keep UAVs aloft indefinitely.

Twelve hours after it rose from the floor, the sprightly, toylike Pelican quadrocopter gently lowered itself back down, bathed in a warm, multicolored glow. What it had done--hovered in place for half of a day--was unremarkable. But how it did that--with the equivalent of 250,000 laser pointers worth of focused light power--represents a broad step forward for the fledgling field.

LaserMotive's technology is fundamentally like a typical solar panel system. The laser beam is captured and focused onto a photovoltaic panel by a series of mirrors. As with many other solar devices, the Pelican has a small reserve battery, just in case the laser is obstructed for a short time. The main difference? This solar power is concentrated and directed, and has a massive potential range.

As it exists, the Pelican drone is distinctly experimental. A super-light, quad-rotor hobby craft that runs off of a purpose-built laser, the Pelican is merely a starting point for extrapolation--something its maker, LaserMotive, is glad to engage in:

Laser power links enable two types of operation.  One is near-continual powering of the UAV, which would therefore need only a very small energy storage device on board. The other is intermittent recharging when the UAV returns to a designated area within reach of the base station; in this case the UAV would need larger onboard energy storage.  In both cases, the laser power link improves on-station time and reduces personnel requirements during UAV mission cycles.

The most compelling of the above possibilities seems to be the intermittent recharging scenario: A drone that could be "refueled" simply by entering a five-mile charge radius for a few hours has obvious and immediate applications.

The Pelican is the second high-profile breakthrough for LaserMotive, which won a $900,000 prize from NASA for the successful demonstration of a laser-powered space elevator device. (Their robot was able to climb to a height of nearly half a mile, at a rate of 3.73 meters per second.)

Before LaserMotive's technology can be built into battle-ready (or space-ready) drones or elevators, they'l need to overcome a few hurdles--most pressingly, that the transfer of power from source to craft is extremely inefficient. Using arrays of near infrared laser diodes, about 50% of the energy is lost in the DC-to-light phase, only to diminish much, much further as it travels through the craft's solar cell and into its motors or batteries. This could be particularly problematic for mobile, truck-mounted charging stations, as they'd need to carry a tremendous amount of energy in the form of fuel or batteries.

Once the technology is mature--and this will likely be more than a few years--LaserMotive has big plans for the technology. UAVs and space elevators are fine and good, co-founder Jordin Kare told MSNBC, but laser power gets truly exciting when you consider its outermost potential. "I've actually done a design for powering a lunar base from Earth."

Here's a video of the Pelican in action:

This post was originally published on Smartplanet.com


You have been successfully signed up. To sign up for more newsletters or to manage your account, visit the Newsletter Subscription Center.
See All
See All