Abstract: Apparatus for detecting high speed hits on a target is disclosed. A first set of detection lines are would in one direction around a target, and a second set of detection lines is wound orthogonal or diagonal to the first set of lines around a target. Where the detection lines are light-transmissive fibers, cutting of a fiber by a high-speed projectile or fragment causes a flash of photons that are detected by a detector attached to that line. Materials the lines are embedded in may also cause bursts of photons when pierced that is detected by detectors. The lines may be laid in prefabricated panels, or attached to an exterior or interior skin of a target. Moldings may be used to ensure that a bend radius of the light-transmissive fibers is not exceeded.

Abstract: An efficient thermal engine is disclosed. In some embodiments, a remainder of energy remaining after an expansion cycle is used to power a subsequent compression cycle. In other embodiments, novel configurations for a larger expansion volume than compression volume are provided. In addition, work of compression may be reduced in a compression cycle, and recovered in an expansion cycle.