Abstract: A honeycomb structure having high levels of recoverable energy absorption is provided. The honeycomb structure achieves high levels of recoverable energy absorption by incorporating cells that exhibit negative stiffness. In one embodiment, the cells exhibit negative stiffness via curved beam members configured to snap through to a second position upon experiencing a sufficient force. The cells may also be configured to snap back to their original position when the force is removed. Therefore, the honeycomb structure may be capable of repeatedly achieving a high level of recoverable energy absorption.

Abstract: A honeycomb structure having high levels of recoverable energy absorption is provided. The honeycomb structure achieves high levels of recoverable energy absorption by incorporating cells that exhibit negative stiffness. In one embodiment, the cells exhibit negative stiffness via curved beam members configured to snap through to a second position upon experiencing a sufficient force. The cells may also be configured to snap back to their original position when the force is removed. Therefore, the honeycomb structure may be capable of repeatedly achieving a high level of recoverable energy absorption.

Abstract: A sensor assembly that replaces a single focal plane array detector with two focal plane array detectors orientated with respect to each other such that a power splitter divides an incoming light source equally between each detector. The two detectors are selected such that the locations of poorly-operating pixels in each detector do not overlay. The output signals of each detector are then electronically or analytically combined to yield 100 percent operability. Separate switchable wavelength filter wheels having one or more different wavelength filters may be positioned between the power splitter and each of the detectors. The power splitter may be replaced by a polarization splitter. One detector can be translated perpendicular to the incoming light source relative to the second detector to compensate for new poorly-operating pixels and/or to improve the spatial resolution.