ABERDEEN PROVING GROUND, Md. -- Whether you see it from a boat or car, do you ever wonder what the white dome structure is on Aberdeen Proving Ground? It's called the Moving Target Simulator, or MTS, and it's one of the U.S. Army Aberdeen Test Center's, or ATC, testing facilities.

Originated in 1984, the completely air-supported facility, also known as the "Bubble", was designed to test any system with a fire control component.

Fire control is the part of a system that allows it to track and engage targets, whether they are stationary or moving. The MTS is "designed as a hardware-in-the-loop Modeling and Simulation facility that has performed extensive tests on combat vehicles such as Abrams tanks, Bradley Fighting Vehicles, and the Stryker Mobile Gun System. There have also been helicopters and hand-held weapons tested in the facility," said Wayne Strine, chief of the Combat Vehicles Division at ATC.

"Additionally, with the rapid advancements in cyber technology, the capabilities of the MTS will continue to expand with applications to ensure potential cyber threats do not inhibit a combat vehicle's ability to hit the target. Likewise, the increased development of unmanned and autonomous systems will require robust test and evaluation to assess the find-engage-kill capabilities of these systems."

Compared to other testing facilities at ATC, the entrance and exit are a little different because the MTS is completely supported by pressurized air. Before entering and exiting the Bubble, a system must pass through a "garage," called an airlock, which allows the pressure to equalize. After the system proceeds to the inside, it moves to the center of the facility for positioning, leveling, and addition of the instrumentation packs to the system.

"Once all instrumentation is added to the vehicle, the sensors and instrumentation are aligned and calibrated. Effectively, the alignment and calibration ensures that everything is looking at the same point in a static, close-distance environment," Neal Rhea, chief of the Fire Control Operations Branch at ATC, explained. "The difference in the sensors is used to calculate the test results once the vehicle is subjected to input such as range to target, horizontal and vertical movement, or ammunition type selected."

Directly in front of the test system is a projection system that displays a particular environment scenario on the actual wall of the structure, which can display multiple targets simultaneously and even simulate different atmospheric conditions.

"When a gunner is actively tracking or utilizing an auto-tracker, the projection system is a vital part of the test. It can evaluate the system performance with and without the individual variances of multiple gunners," Rhea said.

Strine and Rhea agree the two big advantages of the MTS are time savings and cost avoidance, because the mission to investigate and evaluate the ability of a fire control system to track and hit a moving target can be accomplished using hardware-in-the-loop simulation.

"We want to be able to do that in a controlled environment as much as we can to eliminate some of the variables that would occur outside. You're not able to control the exact same conditions in an outside environment, but in the MTS, you can," Strine said. "It's a laboratory setting that allows you to do some pretty intensive investigations and evaluations without the outside effects. It allows us to dig into the hardware and software of a fire control system."

According to Strine, calculations on testing performed since the Bubble's inception have demonstrated over $300 million in cost avoidance. Based on the calculations of future testing, ATC predicts in the next seven years to have $50 to $60 million more in cost avoidance.

"As an example of this cost avoidance, take a typical 1,000-round Abrams test where we would be examining a specific improvement to the tank. If we were to do that 1,000-round test on the range with live ammunition, it would cost a couple million dollars and take several months," Strine said. "When we were perform that test in the Bubble using Modeling & Simulation, we do it in about three weeks for about $50,000 to $60,000."

However, testing still has to be conducted on the range.

"You still have to shoot from moving vehicles and shoot at moving targets, all while the vehicle is being shaken left to right, up and down, back and forth, etc. and in different types of weather," Strine said. "We have to confirm what we've seen in the MTS with actual firing on ATC's open-air ranges."

Rhea added another advantage of the MTS is risk mitigation for the customer.

"If we start with the crawl, walk, run approach using the MTS as the crawl stage, we identify any failures or anomalies early in the acquisition cycle. Then the customer can have the contractor easily remedy the issue before they are putting rounds down range," Rhea stated. This becomes increasingly important as combat systems become increasingly complex and more autonomous.

Recently, the Bubble was given new "skin," also known as the outer layer of the facility. The original skin was only made for a 10-year lifespan, but ended up reaching over 33 years of life.

Rhea stated that over the last couple of years, there was a lot of patching involved to keep the skin functioning to complete the testing mission. That was an indicator it was time for new skin.

The Bubble was deflated for approximately one month to have the new skin installed and then required approximately three to four months to reinstall and recalibrate the test equipment. It is now completely operational, continues its mission, and looks to the future.