For Tankers, The Eyes Have It

For Tankers, The Eyes Have It

See-through ocular computer display delivers situational awareness to men in armor.

U.S. Army tank commanders now are looking up at information the same way fighter pilots do: through a helmet-mounted ocular. The head-up device allows tank crew members situated outside of the hatch to view the same information that is displayed on computers inside the tank. The equipment was introduced with troops in operation Iraqi Freedom.

Many of the tanks deployed in operations today feature the Force XXI Battle Command Brigade and Below (FBCB2) system that provides situational awareness information to tank personnel. However, because the computer displays are located inside the vehicle, the information cannot be viewed from the hatch. As a result, commanders have had to return to the inside of the tank each time they wanted to see updated data. At times, a commander would have to yo-yo between the hatch and the inside of the tank up to 80 times each hour, sometimes when the vehicle would be moving as fast as 60 miles per hour.

Today, a new lightweight helmet-mounted display is delivering this critical data right to the commander while head-up in the hatch. The Nomad Augmented Vision System, developed by Microvision Incorporated, Bothell, Washington, allows tank commanders to view information from computer displays inside the armored vehicle while at the same time continuing to monitor the immediate tactical situation with their own eyes. The system can operate for up to 8 hours on a battery, but it also is hardwired into the vehicle for power.

The Nomad helmet-mounted display consists of a display module attached to a helmet, a video control module mounted to the vehicle and a cable connected to the tank’s FBCB2 computer system. Weighing approximately 1 pound, Nomad features a display resolution of 800 pixels x 600 pixels and a field of view equal to a 17-inch computer monitor at arm’s length. The focus depth can be adjusted from 1 foot to an unlimited distance, and the image refreshes at a rate of 60 hertz.

Bruce Westcoat, aerospace and defense market manager, Microvision, explains that the technology was developed in response to a request from the Army for a capability that would allow tank commanders to relate FBCB2 situational awareness data to what was actually occurring on the battlefield. “Nomad allows the commander to see friendly and enemy positions from the FBCB2 while still looking out on the horizon. This is real-time situational awareness they didn’t have before,” he offers. Capt. Brian Vile, USA, brigade assistant operations officer, 1st Brigade, 25th Infantry Division, Fort Lewis, Washington, emphasizes that viewports and monitors cannot replace an individual taking a firsthand look at the situation.

During the past two years, the system has undergone field trials with the 3rd Brigade, 2nd Infantry Division, and the 1st Brigade, 25th Infantry Division, at the National Training Center, Barstow, California, and the Joint Readiness Training Center, Fort Polk, Louisiana. Since November 2003, 100 Nomad helmet-mounted displays have been deployed in operations in Iraq with the 3rd Brigade, 2nd Infantry Division.

In response to evaluation from testing with the 1st Brigade, 25th Infantry Division, the equipment has been improved. The commander can view information from three different computer displays on the see-through ocular. He can switch from one display screen to another with the flip of a handheld toggle.

The enhanced version still features FBCB2 data, which provides a common operating picture (COP) to all users so they can see the location of all FBCB2-equipped vehicles. In addition, the COP can be populated with the known location of enemy troops.

The second information screen is the gunner’s display. Capt. Vile explains that this is the gunner’s view from the Stryker armored vehicle’s weapon system, generally an M2 .50 caliber machine gun or an Mk-19. “This is important so the commander can confirm targets or direct the gunner to areas where he needs him to engage,” the captain relates.

The driver’s vision enhancer is the third data screen a tank commander has access to using the Nomad system. This thermal viewer allows the vehicle’s driver to see in both dark and dusty environments without relying on light-intensifiers or headlights. With this capability, the vehicle commander can know the terrain features that lie ahead. The electronic information is visible under all lighting conditions, and a filter prevents the display from being detected at night.

Westcoat relates that the initial version was upgraded in additional ways based on input from users. The new version features an automatic brightness control, has two-thirds the volume and weighs less than half a pound. In addition, the cable connecting the ocular to the control module was lengthened and water-proofing was improved so that a commander could use the system in a driving rain. The 1st Brigade, 25th Infantry Division, which recently deployed to Iraq, is using the original version as well as an additional 10 sets of the newer version.

One feature that sets Microvision’s equipment apart from other products is the daylight-readable see-through display, Westcoat explains. This is accomplished by employing a high-intensity light source modulated onto a microelectromechanical systems mirror. The high-resolution image is then scanned onto an ocular in line with the retina. “The advantage is that it’s a single light source; we can control the light source so that it’s very bright or very dim; and we put a filter on the front so that it can’t be detected at night with night-vision goggles,” he says.

Tactical FBCB2 information is viewed through Nomad’s see-through ocular. The data can be projected from 1 foot to an infinite distance, including on the horizon.
Capt. Vile acknowledges that the new version includes improvements but relates that users have identified other disadvantages when using the equipment. “The display is currently monochrome, which makes some icons hard to discern, and it has a cord that the vehicle commander must deal with as he moves in and out of the hatch. Development technology should eliminate these concerns,” he states.

As the troops trained with the Nomad system, one additional obstacle was identified: proper physical adjustment of the ocular. “It takes time and training to get the Nomad properly mounted so the commander can take advantage of it. If poorly mounted, the commander will quickly dismiss the device as useless. Training and experience will quickly ease these concerns,” Capt. Vile maintains.

Although the information is displayed in front of only one eye, the captain explains that this is not an issue for most soldiers. “The user quickly adapts to focusing with either his dominant or nondominant eye as required. This is not a new concept; the AN/PVS-14 night-vision monocular [device] has been in use for a few years,” he notes.

Although Microvision released its newest version of the Nomad just this summer, Westcoat reveals that ideas already are being considered for additional enhancements to the equipment, and programs such as the mounted and dismounted warrior efforts will drive enhancements. From a technology standpoint, form factors, such as a smaller size and three-color displays, will change, he says.

Looking further into the future, Westcoat predicts that the amount of information delivered to the user will greatly increase. Data on the horizon will be indexed so that, for example, when a user looks toward the north, he will see the enemy’s position on the horizon in the north instead of just seeing it on a map. “That technology is available today; it’s just a matter of developing the capability to get it out there. We’ve actually demonstrated a rough version of that capability, but in the future, that’s where it has to go, and it’s not that far off,” Westcoat says.

Capt. Vile offers that ultimately the device should be wireless, and he agrees with Westcoat that color displays are required. In addition, he believes a larger perceived image is needed to make reading messages easier. He also suggests that a quick-disconnect fastener be attached to the cable connector so the device can remain mounted on the headgear when the commander exits the vehicle.