NATIONAL AERONAUTICS AND SPACE ADMINISTRATIONCONTRACT NO. NAS 7-918

TECHNICAL SUPPORT PACKAGE

On

ADAPTIVE CAMOUFLAGE

Inventor(s):

Philip I MoynihanMaurice L Langevin

for August 00

NASA TECH BRIEF Vol. 24, No. 8, Item #

from

JPL NEW TECHNOLOGY REPORT NPO-20706

NOTICE

Neither the United States Government, norNASA, nor any person acting on behalf ofNASA:

a. Makes any warranty or representation,express or implied, with respect of theaccuracy, completeness, or usefulness of theinformation contained in this document, or thatthe use of any information, apparatus,method, or process disclosed in thisdocument may not infringe privately owned

b. Assumes any liabilities with respect to theuse of, or for damages resulting from the useof, any information, apparatus, method orprocess disclosed in this document.

TSP assembled bv:JPL Technology Reporting Office

pp. i, l-5

J E T P R O P U L S I O N L A B O R A T O R YC A L I F O R N I A I N S T I T U T E O F T E C H N O L O G Y

P A S A D E N A , C A L I F O R N I A

August 00

Lightweight optoelectronic systemsbuilt around advanced image sensors anddisplay panels have been proposed formaking selected objects appear nearlytransparent and thus effectively invisible.These systems are denoted “adaptivecamouflage” because unlike traditionalcamouflage, they would generate displaysthat would change in response to chang-ing scenes and lighting conditions.

The basic overall function of an adaptivecamouflage system would be to project, onthe near side of an object, the scene fromthe far side of the object. Although adaptivecamouflage was conceived for use in bat-tlefield settings (see figure), there are alsopotential commercial uses — for example,as an electronic “window” that would dis-play a nearby outdoor scene in an officethat lacks a real window, or as a homesecurity system in place of a door peephole.

A typical adaptive camouflage systemwould likely include a network of flexibleelectronic flat-panel display units arrayed inthe form of a blanket that would cover allobservable surfaces of an object that oneseeks to cloak. Each display panel wouldcontain an active-pixel sensor (APS) [orpossibly another advanced image sensor]that would look outward from the panelthrough an aperture that would occupy onlya small fraction of the area of the panel. Theblanket would also contain a wiring harnessthat would include a cross-connected fiber-optic network, through which the imagefrom each APS would be transferred to acomplementary display panel on the oppo-site side of the cloaked object.

The positions and orientations of all theimage sensors would be slaved to the posi-tion and orientation of one image sensorthat would be designated a master imager.The orientations would be determined by alevelling instrument sensed by the masterimager. A central controller connected to an

external light meter would automaticallyadjust the brightness levels of all the displaypanels to make them conform to the toambient lighting conditions. The undersideof the cloaked object would be illuminatedartificially so that the display from the top ofthe cloaked object would show the groundas though in ambient light; if this were notdone, then an obvious shadow-induceddiscontinuity would be seen by an observerlooking down from above.

The display panels could be sized andconfigured so that a common inventory ofsuch panels could be used to cloak a vari-ety of objects, without need to modify theobjects. Sizes and weights of representa-tive adaptive camouflage systems and

subsystems have been estimated: Thevolume of a typical image sensor would beless than about 1 in.3 (≈16 cm3). A systemto completely cloak an object 10 m longby 3 m high by 5 m wide would weigh lessthan about 100 lb (≈45 kg). If the object tobe cloaked were a vehicle, then the adap-tive camouflage system could readily beoperated on power provided by the vehi-cle electrical system, without adverselyaffecting the operation of the vehicle.

This work was done by PhilipMoynihan of Caltech and MauriceLangevin of Tracer Round Associates,Ltd., for NASA’s Jet PropulsionLaboratory.NPO-20706

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Adaptive CamouflageSensor-and-display systems would create illusions of transparency.

NASA’s Jet Propulsion Laboratory, Pasadena, California

UNCLOAKED CLOAKED

Panels of Adaptive Camouflage Displayingthe Scene From Behind the Vehicle

The Scene From Behind an Object would be displayed on panels on the front of the object.The effect of cloaking is illustrated in this simulated image of an armored vehicle with adap-tive camouflage on one side only.

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Adaptive Camouflage

1. Novelty - Describe what is new and different about your work and its improvementsover the prior art.

This innovation is a dynamic, adaptive camouflage technology which projects the scenefkom the far side of an asset to a display on its near side, and vice versa, as a means of renderingthe asset essentially invisible. This art takes advantage of the recent developments of the verylow power, miniaturized focal-plane array imagers (e.g., the Active Pixel Sensor or APS, CCD,or CID) and light-weight, “rollable” flat-screen displays. There is no camouflage systemavailable that presents a %ee-through” illusion and actively adapts to changing lightingcoIlditiolls~

2. Technical Disclosure

A. Problem - Motivation that led to development or problem that was solved

The DOD is continuously seeking improved camouflage for large assets such as tanks,personnel carriers, and artillery pieces. This need is especially important when an armoredvehicle is stationary and conducting surveillance. The ultimate camouflage is that which rendersthe asset invisible.

B. Solution

An adaptive camouflage system that displays the scenery from behind an asset onto itsfront while continually adapting to changing lighting conditions would render an asset essentiallyinvisible.

C. Detailed Description and Explanation

This innovation is a technique to link electronic viewing devices with conformal displaysfor the purpose of transferring scenery imaged on one side of a vehicle or object to the oppositeside, thereby rendering it essentially invisible to a remote optical viewer as shown in the attachedFigure. Such a device could be applied in a 360 degree con@ura$ion where the small view portsfor the imagers would be interspersed among the large display panels around the vehicle. Thiseffect would essentially give a 360 degree sensing and viewing of the scenery ‘around the asset,thus rendering it invisible from any horizontal or overhead optical observation.

One embodiment of this innovation would involve a network of flexible electronic flat-screen display panels which are arrayed in the form of a blanket designed and configured to fit

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over a given asset. Each rollable flat-screen panel is equipped with, for example, an APS imagerwhich looks outward from the panel. Designed into the blanket is a wiring harness which is across-connected fiber-optic network that transfers the image from an APS imager located on oneside of the asset to a complementary display screen on its opposite side, such that there is anequal number of imagers and screens. The APS imager on each panel is connected with thefiber-optic cable which carries its image to its counterpart on the opposite side. In addition, thepositioning of each APS imager is slaved to a master imager which determines the horizontal andvertical orientations for the entire system. Orientation determination is made with a levelinginstrument sensed by the master imager. A central controller sensing an external light meter isused to autonomously adjust the screen brightness of all panels so that they conform to theconditions of the general environment. To avoid obvious discontinuity, the underside of theasset is lit artificially so that the ground is displayed from its top. When the system is activated,it gives the illusion of invisibility. This effect is shown in Figure 1.

The envisioned system would benefit from the following technical features:,

1. Imaging sensors. The imaging sensors would be small and inexpensive, and hence requiringlow power. An imager’s total volume would be on the order of a cubic inch and would haveapproximately a 30 degree field of view.

2. Fiber-optic connection cable. The fiber-optic connection cable would be light-weight, low-cost, easily repaired, low power requirement, and flexible and would permit high-resolutiontransfer of imaged scenery to the opposite side of the vehicle for display.

3. Conformal “flat panel displays.” These displays would be sized and configured so that acommon inventory of such panels (e.g., commercial off the sheEor COTS) would suit theadaptive camouflage needs of many different systems to include vehicles, humans, and others asappliques not requiring modification of the systems being protected. These too would be lightweight, low cost, and flexible and could be arranged in a mosaic B&ion so as to either render aobject essentially invisible or merely interrupt or modify the objects outline and other distinctiveoptical features.

4. Control system. A control system which would consist of a small, light-weight, CPU whichcould either serve as a mosaic tile coordination center to present high-resolution, coherent scenesor as a repository for storage and play-back of shape altering or scene modifying images forproposes of deceiving and confusing enemy observers.

One embodiment of the envisioned system, as an example, when used to completelycloak an object 10 meters long by 3 meters high by 5 meters wide would weigh less than 100pounds and be easily powered without detriment to vehicle operation using existing 28 Vdcvehicular power. A similar system could also be used to cloak a human. Such a system wouldweigh approximately three pounds and could be powered using existing NICAD batteries for upto three hours of continuous operation.

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The innovation is further envisioned as having the following operational f-s:

1. It requires positive on-off control of the cloaking device which would include the ability toshut down selective display panels so that friendly forces adjacent to or behind the cloakedvehicle would be able to see it while still maintaining invisibility on the side facing the enemy.

2. It would possess cloaking mode selectable control. This future would permit the selection ofcloaking options dependmg upon the requirements of the tactical situation. Selection wouldinclude total invisibility, shape modification to represent a~diEerent type vehicle or object, orshape morphing to obscure identifkble asset shapes or optical characteristics.

The flexibility of this innovation is demonstrated in another embodimentwhere a smallerversion of the envisioned system can be used to cloak personnel. An example of this applicationis depicted in Figure 2.

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“Reference herein to any specific commercial product, process or service by tradename, trademark manufacturer or otherwise, does not constitute or imply itsendorsement by the United States Government or the Jet Propulsion Laboratory,California Institute of Technology.”

“The work described here was carried out at the Jet Propulsion Laboratory,California Institute of Technology under contract with the National Aeronauticsand Space Administration.”