Abstract: A method, apparatus, control system and computer program product are provided for controllably positioning the solar concentrator. The method, apparatus, control system and computer program product determine the respective errors generated by more and different error sources than prior techniques, including error sources selected from the group consisting of a gravitational residue error, an elevation transfer function error and an error attributable to atmospheric refraction. Based upon the respective errors, the method, apparatus, control system and computer program product determine an elevation command and an azimuth command to compensate for the vertical error and the horizontal error between the centerline of the solar concentrator and the sun reference vector such that the solar concentrator can be more precisely positioned, thereby improving the efficiency with which the solar concentrator collects solar energy.

Abstract: A method, apparatus, control system and computer program product are provided for controllably positioning the solar concentrator. The method, apparatus, control system and computer program product determine the respective errors generated by more and different error sources than prior techniques, including error sources selected from the group consisting of a gravitational residue error, an elevation transfer function error and an error attributable to atmospheric refraction. Based upon the respective errors, the method, apparatus, control system and computer program product determine an elevation command and an azimuth command to compensate for the vertical error and the horizontal error between the centerline of the solar concentrator and the sun reference vector such that the solar concentrator can be more precisely positioned, thereby improving the efficiency with which the solar concentrator collects solar energy.

Abstract: A missile intercept system using radiation sensors for guidance that can avoid intercept uncertainty due to unfavorable positions of intense radiation sources, like the sun, moon, or countermeasures flares. When the sensor viewing angle is close to such intense radiation sources, the optics on the kill vehicle may be substantially degraded or even destroyed. The potential for an "out of the sun" attack cannot be avoided when international treaties restrict each country to a single defense site while potential launch sites are proliferating about the globe. Therefore, two kill vehicles are launched when an intercept planner determines that the viewing angle from the kill vehicle to the target vehicle will be looking at or near the sun during the engagement. A surrogate kill vehicle is launched on a trajectory that will "fly-by" the target vehicle with viewing angles that will not "see" the sun.