Important properties for camouflage materials can be summarized in six criteria: (1) spectrally selective reflectance, (2) low gloss, (3) low degree of polarization, (4) low infrared emissivity, (5) non-destructive effect on radar properties and (6) color adaptivity. We have studied a collection of natural materials for potential use as camouflage surfaces for the arctic region. The four first camouflage criteria are analyzed using spectrometry, scatterometry and spectroscopic ellipsometry techniques. The materials involved in the study are diffuse white nature-inspired surfaces: Cuticles of the beetle Cyphochilus insulanus, and foams of freeze-casted cellulose nanofibrils.

We present data that partly fulfills the addressed camouflage criteria. An adequate reflectance is achieved in the spectral range of 400–1600 nm for both samples. Scattering data show that near-Lambertian properties are achieved at 633 nm for both surfaces but at 1550 nm for only the beetle cuticle. The degree of polarization is low for unpolarized light incident near the surface normal for both surfaces.

With the increased threat from advanced sensor systems using several wavelength bands and sensor fusion, the requirements on camouflage increase. Consequently, in order to reduce the risk of EU soldiers being detected, identified and engaged, adaptive camouflage prototypes have been developed, implemented and demonstrated.

Several active and passive adaptation mechanisms were integrated into a textile-based soldier camouflage system. The prototypes address several wavelength bands, including visual, thermal infrared and radar. Military needs on sensing, fire power, mobility, compatibility with other equipment and wearing endurance were considered.

The demonstration, at TRL5, took place in a relevant environment, an area adjacent to vegetation and buildings close to Paris, France. The reduction in detection range and hence the increase in survivability, as established in field trials previously conducted in Portugal and France, was made clear during the demonstration. The demonstrated technology comprised actively controlled light emitting diodes and thermochromic materials for visible signature adaptation, phase change materials and biologically degradable insulating cellulose cells (cork) for thermal camouflage and radar absorbing coatings with conjugated polymer compositions. Two suits were shown with soldiers walking along a treeline and in front of buildings.

Prior to the public demonstration laboratory tests of the materials and components had been performed as well as ergonomic tests, signature measurements in different backgrounds and light conditions and radar cross section measurements at an outdoor test range.

Production technologies were studied and production cost estimated. It was concluded that a similar system can be produced at a reasonable cost and the production scaled up to larger volumes.

Throughout the project, dialogue with military end-users was upheld concerning requirements and applicable environments and tactical situations in order to ensure relevance. Military end-users from Sweden, Portugal, Germany, France, Lithuania and the Netherlands were invited to the final workshop and technical demonstration.