Abstract: A dual stage vehicle attitude control system includes a first attitude control module having at least two momentum wheels arranged to provide zero momentum vehicle attitude control, each momentum wheel comprises a limited travel two axis gimbal that pivots the momentum wheel along two of the three axes of the vehicle, a second attitude control module having reaction wheels arranged in a pyramid configuration to provide vehicle attitude control along at least one control axis that is common with a control axis of the at least two momentum wheels, and a controller connected to the first attitude control module and the second attitude control module, the controller being configured to coordinate actuation of the first attitude control module and the second attitude control module to rotate the vehicle in at least one of three axes of a vehicle.

Abstract: A dual stage vehicle attitude control system includes a first attitude control module having at least two momentum wheels arranged to provide zero momentum vehicle attitude control, each momentum wheel comprises a limited travel two axis gimbal that pivots the momentum wheel along two of the three axes of the vehicle, a second attitude control module having reaction wheels arranged in a pyramid configuration to provide vehicle attitude control along at least one control axis that is common with a control axis of the at least two momentum wheels, and a controller connected to the first attitude control module and the second attitude control module, the controller being configured to coordinate actuation of the first attitude control module and the second attitude control module to rotate the vehicle in at least one of three axes of a vehicle.

Abstract: Systems and techniques for laser metrology. Two or more fanned probe beams are scanned relative to a surface including one or more targets. A position detection module receives return beam information from the fanned probe beams, and determines a position of at least a first target of the one or more targets based on the return beam information.

Abstract: One or more fixed-orientation fanned laser beams and one or more displacement measurement devices to precisely measure the orientation of a payload platform are disclosed in a metrology system and method. The measurement devices may be distributed at locations across a payload platform such that displacement changes of these devices can be used to accurately determine platform pointing. Laser beam transmitters may be fixed in the same reference block to which a spacecraft attitude sensor is mounted. Fanned laser beams are transmitted from these sources to the measurement devices so that their displacements can be determined with respect to the plane of the fanned beams and thereby with respect to the spacecraft attitude sensor. Only a small number of fixed laser beams are needed to achieve precision measurements at a reduced cost, weight and power, and with increased system reliability and simplified system integration.

Abstract: Systems and techniques for laser metrology. A system may include a laser source and a fanning apparatus configured to generate a fanned laser beam. The fanned laser beam may be scanned across the surface of an object, and may reflect off a plurality of targets positioned on the surface. A position detection module may determine a position of the metrology targets based on the reflected beam.

Abstract: Various embodiments of the present invention are directed to precision control system for spacecraft gimbaled payloads. Embodiments of the invention provide an innovative technique of calibrating gimbals disturbances to directly canceling gimbal control disturbances. Such a calibration system includes a receiver for receiving telemetry data for pointing a payload, a processor for calculating a disturbance parameter vector for a gimbal disturbance model with the telemetry data and a transmitter for transmitting the disturbance parameter vector to compensate for pointing error when applied in pointing the payload. The gimbal disturbance model comprises a harness stiffness term, a disturbance harmonics term and at least one friction hysteresis term. The telemetry data may be time matched prior to calculating the disturbance parameter vector.

Abstract: A photodefineable mixture comprising oligomeric divinyltetramethyldisiloxane bisbenzocyclobutene as its major resin component dissolved in mesitylene and at least 2,6-bis(4-azidobenzylidene)-4-ethylcyclohexanone as a photosensitive agent in an amount sufficient to convert the mixture to an organic-insoluble solid upon exposing the mixture to photon radiation is disclosed. These polymer compositions are useful as thin film dielectrics in electronic applications such as multichip modules, integrated circuits and printed circuit boards.