Together with Germany and Canada the Netherlands Army has developed a prototype adaptive camouflage system. The Dutch part of this research project, coined CAMELEON, was performed by TNO and the Holst Centre. CAMELEON focused on developing and implementing new materials and methods to create adaptive camouflage patterns. The idea is to render objects or persons invisible by covering them with a material displaying a camouflage pattern that dynamically adapts its shape, color and brightness to the local background.
The current prototype demonstrates adaptive camouflage for the naked eye. We also extended the technique to other spectral wavebands, to provide adaptive camouflage against night vision devices and thermal sensors.
TNO Holst Centre has developed new Polymer L.E.D. (or PLED) elements with a high light output, which makes them especially suited for daytime adaptive camouflage. PLEDs can be made on lightweight flexible substrates that can cover large areas. Additional benefits of PLEDs are their low power consumption and light weight. Furthermore, smart PLED designs enable the production of light sources that can be bended over arbitrary curved surfaces. Other promising materials that were investigated are electrochrome materials, that act like tunable colour filters. These can be used to create reflective elements that behave like paint with a variable color. Combined with PLEDs electrochrome materials enable camouflage with varying color and brightness.
The prototype system consists of an active pixel array of PLEDs, covered with color filters, a digital camera, and a laptop. The laptop computes an adaptive camouflage pattern from the scene registered by the camera, and displays this pattern on the PLED array by controlling the light output of each individual PLED.
The adaptation process is performed automatically and is controlled by the laptop. First, a picture is taken of the adaptive panel in its local background, and an area around the panel is adopted as a characteristic background sample. Next, a series of test patterns is generated, presented on the array, and registered by the camera. These images are used to derive the relationship between the input value to the PLEDs and their output color for the four different filter types used. Initial analyses show that four filter colors are sufficient to represent the colors that characterize a typical woodland environment. Finally, the TNO algorithm calculates and generates a camouflage pattern that is adapted to the background of the array.
In the future flexible PLEDs will become available that can for instance be applied in fabrics. Dynamic adaptive camouflage will become possible by integrating sensing elements into the array. Larger flexibility in color adaptation will be achieved by the use of electrochrome materials.
The use of materials that can dynamically adjust their near and far infrared spectral signatures will extend the deployment of adaptive camouflage systems into night time conditions. The CAMELEON project has successfully demonstrated that adaptive camouflage is no longer an illusion but will become available in the near future.