Remember Bond’s Aston Martin sports car that could merge completely into the background, appearing invisible to his foes? The principle, as explained to Bond by his ever-patient technology advisor, was in fact very close to what has been developed by BAE Systems and revealed last September in London.
By using tiny closed-circuit video cameras spread around a vehicle, an image can be projected onto special material covering the vehicle, which can then replicate its surroundings, thus rendering the vehicle invisible. As the vehicle moves, so does the background projection.
In the complex and dynamic environment of the modern battlefield, the capabilities of the latest precision weapons make slow-moving or static targets easy prey for tanks, attack helicopters, and drones looking for a kill. Camouflage netting and disruptive paint schemes can confuse visual monitoring, but when IR seekers are employed, the target’s hot spots are a sure giveaway. But this is about to change.
The rapid increase in the use of advanced electro-optical sensors saw the need for some highly radical “out of the box” thinking to continue to ensure survivability in a battlefield environment. Warfighting in such military theaters of operation as Iraq and Afghanistan enabled the coalition forces to use overwhelming force and superior technical capabilities to overcome opposing hostile forces, but technical superiority and weight of numbers cannot be guaranteed for future campaigns, and it would be dangerous to assume that enemy forces will always be represented by primitively equipped adversaries.
Where such enemies may have access to more modern IR sensors, the tactical balance could be quickly reversed, with serious consequences for coalition forces. If friendly forces can remain hidden, or made more difficult to target, then a war-winning edge is easier to sustain. Some progress has been made in recent times in making vehicles more difficult to locate through sophisticated “passive” countermeasures, including radar and IR camouflage cloaks and even pixilated paint schemes that confuse some target-seeking sensors that cannot recognize the “library” signature of the target.
But these can only be effective with static objects, not vehicles or aircraft on the move.
BAE and Sweden’s Defence Materiel Administration (FMV) partnered to co-develop a practical invisibility cloak that will allow a target to blend into its surroundings. After several years of work so far, the electronic camouflage innovation has shown itself to be a practical solution, and now the technology is moving into the development phase following highly successful tests involving armored vehicles and target-seeking sensors. The future potential for the concept, Adaptiv, is enormous, and clearly has possible applications for ship and aircraft protection as well as surface vehicles.
The patented technology is based on sheets of hexagonal “pixels” that can be programmed to change temperature very quickly. Onboard cameras pick up the background scenery (urban or rural) and display that IR image on the platform, allowing even a fast-moving tank to match its immediate surroundings. As an alternative, the combined screens can mimic another vehicle, such as a civilian truck or a farm tractor. This level of camouflage flexibility has never been possible before.
“Earlier attempts at similar cloaking devices have hit problems because of cost, excessive power requirements, or because they were insufficiently robust for operational use in a battlefield environment,” said Peder Sjolund, Technologies Special Executive, Global Combat Systems Vehicles, BAE Systems. “Our panels can be made so strong that they also provide useful armor protection and consume relatively low levels of electricity, especially when the vehicle is at rest in a ‘stealth recce’ mode and generator output is low.
“We can resize the pixels to achieve stealth for different ranges. A warship or building might not need close-up stealth, so could be fitted with larger panels.”
With such panels fitted to a typical small coastal patrol ship, for example, its signature could be made to resemble that of a fishing boat or small car ferry. Helicopters are another obvious suitable platform for the Adaptiv technology, presenting a very effective stealth profile with a small weight penalty. Use on helicopters or all-terrain vehicles for Special Forces missions behind enemy lines would greatly reduce vulnerability to observers on the ground or in other helicopters, using IR sensors, and the ability to display identification tags, invisible to non-friendly forces, would minimize fratricide incidents.
“There are [several] modes to avoid detection," said Peder. "You can hide the vehicle, you can disguise it, and you can identify yourself to your own forces and communicate with them. By changing the IR shape of the object you are trying to hide or disguise, you in effect make it simply disappear. It can no longer be seen, but it is still there functioning as required. By making up ID tags that only friendly forces can see and identify, you can establish a pattern that allows covert communication without having to use a radio.”
Typically an armored vehicle might have 1500 Adaptiv tiles fitted, all linked to cameras and into an integrated display system and controlled automatically by an onboard computer. Heat can be transferred around the vehicle very fast, removing 70°C (126°F) from the surface in seconds, using semi-conducting technology. Wherever possible, the prototype systems have used as many commercially available components as possible to keep down costs and development risks. The transition time for switching the system on, or merging from one background to another, is almost instantaneous.
Over the last four years, the development work share between FMV and BAE Systems has been around 50% each. One useful side effect when using the tiles on a ground vehicle, such as a tank, is a reduction of 10 dB in noise levels and a similar reduction in internal vibration levels. The individually mounted tiles are very easy to remove and replace and are designed to be resilient enough to withstand typical cross-country movements.
BAE is working on alternative cloaking options that might allow the technology to be incorporated into molded shield sections that could include compound curves and other shapes that would maintain a streamlined form for high-speed platforms.