Abstract: A waveguide includes a grating structure with discontinuous regions of diffraction; regions of diffraction are interleaved with regions of no diffraction. The regions of diffraction and no diffraction may vary in size such that the width of each successive region of diffraction increases across the face of the waveguide. Neighboring regions of diffraction, separated by regions of non-diffraction, may define different periods.

Abstract: A system and method for controlling roll in a projectile. The novel system (56) includes first (52) and second (58) sections adapted to counter-rotate relative to each other and a mechanism (76) for inducing the counter-rotation to generate a roll torque on the projectile (50). In the preferred embodiment, the mechanism (76) is a motor comprised of a rotor (64) affixed to the first section (52), and the second section (58) which acts as a stator that rotates around the rotor (64) when a current is applied to the armature. In an alternative embodiment, the second section (58) is turned by a motor (80) attached to the first section (52) which drives a small gear engaging a full-diameter ring gear (82) on the second section (58). In the illustrative examples, the first (52) and second (58) sections are a missile forebody and a tail section of the projectile.

Abstract: A system and method for controlling roll in a projectile. The novel system (56) includes first (52) and second (58) sections adapted to counter-rotate relative to each other and a mechanism (76) for inducing the counter-rotation to generate a roll torque on the projectile (50). In the preferred embodiment, the mechanism (76) is a motor comprised of a rotor (64) affixed to the first section (52), and the second section (58) which acts as a stator that rotates around the rotor (64) when a current is applied to the armature. In an alternative embodiment, the second section (58) is turned by a motor (80) attached to the first section (52) which drives a small gear engaging a full-diameter ring gear (82) on the second section (58). In the illustrative examples, the first (52) and second (58) sections are a missile forebody and a tail section of the projectile.

Abstract: An externally powered electric vehicle with an on-board variable speed AC drive motor drawing power from an overhead trolley line. The vehicle may include an auxiliary power source in the form of a battery or internal combustion engine for powering the vehicle when the vehicle is disconnected from the trolley line.