Abstract: An Impact sensor for detecting strain or strain rate in a composite having one or more sensor nodes using a fracto-mechanoluminescent (FML) material, such as EuD4TEA crystals, encased in an optically transparent material such as PDMS. Optical fibers transmit light emitted by the FML material due to strain experienced by the composite. For honeycomb composites, the transparent material is disposed within cells of the honeycomb composite. A reflective material such as Mylar either surrounds the optically transparent material or lines the cell. The intensity of the light emitted by the FML material is related to the magnitude of strain or strain rate experienced by the composite as well as the distance of the FML material from the surface of the composite that receives the impact. Multiple sensor nodes disposed at different distances from the impact surface can provide a three-dimensional map of damage experienced by the composite.