How do military aircraft helmets track where a pilot is looking?
- By Joe Pappalardo
- AirSpaceMag.com, August 01, 2007
The Lightning II helmet being developed for the F-35.
Rockwell Collins
These days, fighter pilots' helmets are nearly as complex as their airplanes. And with good reason: If the helmets can't tell where the pilot is looking, many of the airplane's systems, including weapon targeting, are useless.
The folks at San Jose, California, who have designed advanced U.S. military helmets for the F-15, F-16, and F/A-18, make their living at the nexus between man and machine. VSI's flagship program is the Joint Helmet Mounted Cueing System. It uses a magnetic field in the cockpit to sense the orientation of the helmet, then feeds information on the current line-of-sight to the aircraft's flight computer. VSI's helmet has an accuracy of about four milliradians, an angular measure commonly used in the world of shooting and targeting. One milliradian equates to one one-thousandth the distance to the target. So if the target is 1,000 feet away, you'd be accurate to within a foot.
Determining where a pilot is looking by tracking eye movement is a much taller order. "You would not believe some of the human factor issues you have to overcome to have a successful eye tracker," says Louis Taddeo, VSI marketing director. "Although we have research projects into eye tracking, it is a very difficult task both from a technical [standpoint] and the physiology."
So for now, VSI uses helmet position to achieve that four-milliradian accuracy. Pilots need only turn their heads to aim their weapons, even during high-G maneuvers, freeing their hands for other tasks.
The head-up displays (HUDs) currently used in fighter aircraft are sophisticated, but they have a single, fixed point of view. Future helmets will include virtual displays projected across the visor, where the pilot can see information and targeting prompts. The F-35 Lightning II helmets due to enter service in 2012 will offer what Taddeo calls "extreme off-axis targeting." Instead of having to turn the airplane toward the target to frame it in a fixed-view HUD, the pilot will be able to see targets that are off-axis, or not in the direction of flight. Like its predecessors, the Lighting II helmet will use magnetic head tracking, but VSI says the accuracy will be greater, courtesy of software upgrades that combine head position with eye location and data from the HUD.
Lockheed Martin test pilot Jon Beesley took the new helmet for a test drive last April in the first pre-production F-35. It was the first time a pilot in a tactical fighter had flown without a HUD in at least three decades. Expect more flights if the reviews are good.
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Comments (3)
Could you tell me how the ROC/VSI instrument is affected by altitude.
Thank you,
John Lawton
PS
I understand that the basic ROC/VSI obtains its input by the rate at which pressure in a reference chamber changes due to the flow through a calibrated orifice which is connected to the aircrafts static line. It would seem to me that the
indication of such an instrument would depend on the altitude of the aircraft because the rate of change of atmospheric pressure with altitude changes with altitude.
Posted by John G. Lawton on July 29,2009 | 09:33 PM
Dear John,
we are some German students working on a project about Eye-Tracking. One part of our presentation is the creation of Use Case characteristics. For this characteristics we would like to use the photo at the beginning of your article. Is this possible? EDITORS' REPLY: You need to contact Rockwell Collins, who supplied the photo. They hold the rights to it. email: brand@rockwellcollins.com
Posted by Mona on May 14,2010 | 03:31 AM
Hello,
I'm an airline pilot who wears glasses (no contacts), and I'm looking for Flight sunglasses. I was wondering if any device exists that attaches to the headset, and holds a "shield" type sunglass, just like a helmet would do. Goal is to avoid any side pressure from the earcups (even though my Zulus ANR is a big improvement over my previous headset).
Posted by Patrice on June 12,2010 | 04:43 AM