Slashdot Mirror
Military Robots to Gain Advanced Sight
coondoggie brings us a NetworkWorld report discussing iRobot's plans to include Laser Radar technology in their military robots. Quoting:
"Specifically the robot-maker is licensing Advanced Scientific Concepts' 3-D flash Ladar which uses laser beams to scan and process targets. The system has the ability to create a virtual 3D picture of an entire area. IRobot ... believes the technology will provide new navigation and mapping capabilities for future generations of robots and unmanned ground vehicles and pave the way for autonomous vehicles to lead convoys into dangerous territory, search contaminated buildings for casualties, or enable bomb squads to safely investigate suspicious objects."
Maybe iRobot will put this into their Roombas and allow us to get rid of some of the IR gates that they use now. I don't know how many times I've stepped on one of them after they migrate to the center of the room in the dead of night.
Also, does anyone else find it disturbing that they also make military robots?
I'd figure there also are a lot of civil applications for this technology? Contracting, driver-less cars, game-development? Oh, the fun we'd have.
This is a big step forward. I know this technology. Back in 2004, when we were putting our DARPA Grand Challenge vehicle together, I went down to Advanced Scientific Concepts in Santa Barbara to see the thing. Back then, they had a prototype that worked, but it was on an optical bench (one of those big plates with screw holes to which you attach optical components), nowhere near ready to go on a vehicle. It was just too early. We had to go with SICK rotating-mirror line scanners, like everybody else. But I was convinced it was the right direction to go, and I dragged a venture capitalist who had some underperforming photonics companies down there to see the thing. He didn't want to fund them, because they were too far from a consumer product; the near term market was DoD-only.
ASC kept working, and by 2006 they had working portable prototypes. By 2007, you could buy a LIDAR about the size of a large-format camera for about $100,000. Now they've downsized it further.
Unlike the laser scanners with spinning mirrors or sensors, which is what everyone else uses, this technology has no moving parts. The system has two main components - a pulse laser with diffusing optics, and a detection and timing IC with one LIDAR receiver per pixel. Neither of these is inherently expensive in quantity. It may take a while to get this down to webcam prices, but $1000 is a reasonable near-term target.
It's amazing that this can be done in an eye-safe way, since this approach is subject to the radar equation - returned power decreases as the fourth power of the distance. But the detectors can be made good enough. Some of their more sensitive detectors use a photomultiplier tube technology, like a night vision system. Night vision systems use a photoelectric detector plate - when a photon hits it, an electron pops out. Electric fields are used to accelerate the electron, which then hits one of the electron detectors on a specially designed IC. Photomultipliers have been around for decades, and can detect single photons. The neat thing about the photoelectric effect is that it's at the atomic level, and happens in picoseconds. So it can be used as a light amplifier for a time-of-flight LIDAR.
The current generation of compact sensor is 128x128 pixels at 30Hz. The sensors are currently smaller than the lasers, but for smaller robots where you need only 10m of range or so, a smaller laser can be used.
This is the sensor that will make automatic driving commercially feasible.
I'd have to question your "returned power decreases as the fourth power of the distance" claim.
:P
This is true with radar, yes, because your radar beam increases spatially in two dimensions on the way to the target, ping at a point source, then diffuses again in two dimensions from there.
With lidar, you have a coherent focused beam on the way there. Lasers are generally considered to not lose any significant power over distance in a vacuum. You still have the ping, or reflection event, at which point you'll no longer have coherent, focused light, and the return trip will indeed be subject to the two-dimensional decrease in power.
Hence lidar is subject to the inverse square law, not the inverse fourth-power law.
and as a brief aside, I did some research with nasa in what seems to be a similar field. We were evaluating commercial off the shelf "range imager units", which are effectively the same thing as described here, only with an array of phased-intensity IR led's instead of a laser, as with a laser, you actually have to scan a scene. That's the difference between lidar and range imaging. judging from the extremely light details in the article and being too asleep to do any further research of my own, i say this seems exactly like what they're doing. using COTS stuff that's been around for years (and quite small, and available commercially, since at least 2005), only they claim to be using a laser light source. I don't get it. they claim there is no moving parts, there is no scanning mechanism to flood the scene with a single laser beam, one point at a time. they allege that a single laser beam paints an entire scene with no moving parts. i call bs, unless that's one wide, wide laser beam. perhap's it's just laser diodes, and then the whole idea is -exactly- like the range imagers like i worked with years ago.
also, wtf is Ladar? it's Lidar, idiots
The US didn't become successful because it won the 2WW. It won the 2WW because it was already on the way to become successful. Oh, and the russians helped a lot, too.
Fleur de Sel
If a job's not worth doing, it's not worth doing right.