iRobot Corporation (NASDAQ:IRBT) badly wants a chance to mow the grass on your lawn. But first, it'll need to tackle a problem in the sky. Specifically, Scientists at West Virginia's National Radio Astronomy Observatory have objected to iRobot's recent request for permission from the FCC to sell robotic lawn mowers.
A challenge of galactic proportions
For perspective, FCC documents recently revealed that iRobot has asked for a waiver of rules prohibiting the unlicensed operation of certain fixed wideband wireless systems. If the FCC were to grant such an exception, iRobot says it would allow the company to market and receive certification for robotic lawn mowers guided by wireless beacons installed throughout the yard. iRobot further notes that while robotic lawn mowers are already "well accepted in Europe," the only models available in the U.S. require placement of underground electric fences -- a costly, burdensome process that has prevented wide-scale adoption here.
According to the NRAO, iRobot's wireless beacons could potentially interfere with sensitive radio telescopes it uses to study the stars. In this case, iRobot wants its lawn mowers to operate at frequencies in the range of 6240 to 6740 MHz. And the NRAO, for its part, uses a subset of that range to identify methanol in space "that is abundant in star-forming regions and serves as a galactic beacon of star-forming activity."
Keeping in mind that cell phones are already banned near such observatories, NRAO spectrum manager Harvey Liszt lamented: "We'll see the whole thing with our electronics. It's a distortion."
But it also appears iRobot saw this coming. Near the end of its initial request to the FCC, the company wrote:
iRobot recognizes that the Radio Astronomy Service ("RAS") uses 6650-6675.2 MHz for spectral line observations. Because this use is location specific, there is little risk of interference as homeowners will not be operating the [robotic lawn mowers] near observatories, especially those located in desert or mountainous regions. As well, the above ground attenuation of the RLM, ground clutter, and the curvature of the earth will combine to protect RAS.
iRobot further promised to further minimize the chances of interference by placing a notice in the user manual and on the robot stating, "Consumer use only; use must be limited to residential areas."
Back and forth
The NRAO disagreed in its response and outlined calculations indicating that it would require an 89 km line-of-sight separation distance between its equipment and iRobot's lawn mowers. For perspective, that would equate to an area of nearly 25,000 square km, or nearly 10,000 square miles surrounding each affected observatory.
iRobot argued back, "This radius is overstated," citing its own math stating the actual claimed radius should be "a maximum of 19.3 km, before considering other factors." iRobot also noted that 10 of the 13 potentially affected NRAO observatories are subject to a completely different interference threshold, "which reduces the radius of interference from an iRobot beacon to only 610 meters with perfect line of sight." The only residences that come close to fitting that criteria, iRobot says, are those at North Liberty, Iowa, "which is a heavily forested site."
iRobot also pointed out that granting this exception would be in the interest of the greater good. From 2010 through 2013, iRobot says, an average of 38,000 people per year were treated in hospital emergency rooms for walk-behind power-mower injuries. And over 1,500 people died in lawn mower accidents from 1997 to 2010.
"It is reasonable," iRobot elaborated, "to assume that many of these injuries and deaths would not occur if consumers used a robotic mower and were able to maintain a safe distance while their lawns are mowed."
But the NRAO responded, "There is already a competitive market for robotic lawn mowers using wire loops, which has somehow failed to stanch the stream of ghastly accidents and spilt gasoline that iRobot associates with the mundane practice of lawn-mowing." It went on: "Robotic lawn devices are expensive, typically several thousand dollars, and meant for situations where mowing is performed far more frequently than in the typical front yard."
However, that seems to miss the point and ignores iRobot's premise that its wireless system could significantly broaden adoption of robotic lawn mowers. This also discounts the possibility that iRobot could use its expertise in the robotics space to bring a more affordable alternative to the RLM market.
This, too, shall pass
To be fair, the NRAO admits that "iRobot's RLMs can certainly operate over most of this country without interfering with radio astronomy operations." But it also insists that those robots must be prevented from operating across the protected band in the rare cases it might cause interference. To ensure that happens, the NRAO suggests installing GPS devices to prevent operation in restricted bands -- something iRobot would almost certainly want to avoid to minimize both its hardware costs and the retail price of the commercialized machines.
Alternatively -- and keeping in mind that the NRAO's range doesn't completely encompass the one iRobot seeks -- iRobot could narrow its requested robotic lawn-mower operating frequency band to avoid the protected range altogether. That seems fair enough, though it remains to be seen whether doing so could have unexpected negative technical ramifications on iRobot's development of the new product.
In the end, the final decision will come down to who the FCC believes has the more persuasive case. While I'm not an expert in radio frequencies, it appears iRobot should have little trouble either persuading the FCC to side with its plight, or at the very least find an acceptable workaround to avoid infringing on the NRAO's turf.
Over the long term, that's why I'm still convinced it's only a matter of time before iRobot's wireless robotic lawn mowers arrive at a lawn near you.