Abstract: Apparatus, and a corresponding method for its operation, for precisely moving a movable rotor by urging a motor, such as a piezoelectric motor, into operative engagement with a circumferential rim-like portion of the rotor, with a radial preload force great enough to produce tangential motion in the rim-like portion and thereby to move the rotor in any desired manner and with very high precision. Possible damaging effects of the radial preload force are canceled by the introduction of an oppositely directed radial resistive force, such as by means of one or more pinch rollers positioned opposite the motor and also engaging the rim-like member. The motor is mounted in an assembly that permits limited sliding and pivoting movements of the motor and thereby allows the motor to adapt to any physical irregularities in the driven rim-like member.

Abstract: Apparatus, and a corresponding method for its operation, for precisely moving a movable rotor by urging a motor, such as a piezoelectric motor, into operative engagement with a circumferential rim-like portion of the rotor, with a radial preload force great enough to produce tangential motion in the rim-like portion and thereby to move the rotor in any desired manner and with very high precision. Possible damaging effects of the radial preload force are canceled by the introduction of an oppositely directed radial resistive force, such as by means of one or more pinch rollers positioned opposite the motor and also engaging the rim-like member. The motor is mounted in an assembly that permits limited sliding and pivoting movements of the motor and thereby allows the motor to adapt to any physical irregularities in the driven rim-like member.

Abstract: A space telescope having a primary mirror for focusing and reflecting electromagnetic radiation, multiple secondary mirrors and, optionally, multiple tertiary mirrors, for receiving the focused and reflected electromagnetic radiation from the primary mirror and reflecting the electromagnetic radiation, and multiple focal plane arrays for receiving the focused and reflected electromagnetic radiation from the secondary mirrors or tertiary mirrors. The use of a multiple secondary mirrors and multiple focal plane arrays allows the telescope to observe multiple fields of regard simultaneously in selected celestial regions or on an orbited celestial body, such as the Earth.

Abstract: A pressure vessel and method for producing a pressure vessel is disclosed. The pressure vessel comprises a liner shell fabricated from composite material applied to a soluble mandrel having a body shaped to pattern an interior of the pressure vessel, the liner shell having an opening, a boss having an aperture therethrough, the boss sealingly bonded to the liner shell with the aperture adjacent the opening, and an outer shell fabricated from plies of composite material filament impregnated with matrix material wound over the liner shell and the boss, but not over the aperture.

Abstract: A structureless space telescope is disclosed. The structureless primary mirror includes a plurality of mirror elements for focusing and reflecting electromagnetic radiation, and the telescope further includes at least one secondary mirror and possibly a tertiary mirror for receiving the focused and reflected electromagnetic radiation from the structureless primary mirror and reflecting the electromagnetic radiation, and at least one focal plane array for receiving the focused and reflected electromagnetic radiation from the secondary mirror or tertiary mirror, wherein the plurality of mirror elements, the secondary mirror and the focal plane array are coordinated and controlled without a physical structure connecting the plurality of mirror elements.

Abstract: A pressure vessel (10) and a process for its fabrication, the vessel (10) having a liner shell (16) formed from composite materials cured out-of-autoclave, and an outer structure (18) formed by winding or laying up additional layers of composite material over the liner shell. The liner shell (16) is formed as two halves, each with an opening into which a boss fitting (20) is installed. The two halves may be separately formed by a lay-up process, or first formed as a whole liner shell by filament winding, the whole liner shell then being cut in half to permit installation of the boss fittings (20). After curing, the halves are assembled and the outer structure (18) is wrapped over the liner shell (16) and also cured out-of-autoclave. The resulting pressure vessel (10) can be used for reliable storage of cryogenic or other materials, yet is light in weight and not costly.

Abstract: The method uses a physical phenomenon of dispersion of the optical rotation for identification of the spectral characteristics of light Polychromatic linearly polarized radiation passes through the environment that rotates a polarization plane of its spectral components, depending on their wavelength. After a subsequent passage through the analyzing polarizer, a dependence of the light intensity S(&phgr;) on the angle &phgr;, that the analyzing polarizer forms with the polarization plane of the analyzed light, is measured. S(&phgr;) is in a mathematical relationship with the spectrum of the analyzed radiation I(&lgr;), where &lgr; is a wavelength. S(&phgr;) allows for the determination of the spectral characteristics of the analyzed radiation. In devices based on the above principle, the collimated polarized beam of the analyzed radiation passes first through the optical element that exhibits a dispersion of the optical rotation, i.e.

Abstract: A magnetic torquer (10) for spacecraft attitude control, providing a torque that is controllable over an extended range greater than a normally used linear range, and thereby providing a higher ratio of maximum torque to device weight. In one form of the torquer, a feedback loop including a sensor (20), a signal subtraction circuit (24), a controller (28) and an adjustable power supply (16), continuously determines a corrected command signal that results in the generation of a desired magnetic moment and a corresponding torque, over the extended range, regardless of non-linearity across the extended range. In an alternate form of the torquer, the corrected command signal is generated from a mathematical model (56) of the magnetic torquer (10). Use of the invention also minimizes the effect of any residual magnetic moment that might by present when the actuating current is reduced to zero.

Abstract: A method for increasing the payload that can be delivered by a given launch vehicle to a selected target in an interplanetary space mission, without increasing the transfer time to reach the target. In accordance with the disclosed method, a conventional multi-stage launch vehicle is used to accelerate a payload spacecraft to near earth's escape velocity. Then the spacecraft is separated from the upper stage of the launch vehicle and is further accelerated by applying a velocity impulse with an onboard propulsion system into a transfer trajectory that takes the spacecraft to the target planet. Because the upper stage of the launch vehicle is not accelerated into the same transfer trajectory, a larger payload mass can be delivered to the target planet without increasing the transfer time. Alternatively, the transfer time can be reduced without decreasing the payload mass or changing the launch vehicle configuration.

Abstract: Three folded Maksutov/Bouwers telescopes formed in a single housing to provide focused images from three angularly spaced fields of view. The fields of view are positioned 30.degree. from a central axis and are spaced 120.degree. apart in azimuth. Light enters the telescopes through a common upper aperture, in which a concentric corrector is installed, is reflected from a common lower plane mirror and from one of three inclined mirrors into one of three spherical primary mirrors. The spherical mirrors focus the respective beams onto three focal planes located outside the housing, through openings in the respective inclined mirrors. The concentric corrector compensates for spherical aberration in the spherical primary mirrors, without the need for holographic optical elements, resulting in a simple, compact, lightweight and low-cost device.

Abstract: A low-cost, liquid-propellant rocket launch vehicle having a central pod that carries an optional final-stage rocket engine cluster, and having additional engine clusters arranged in diametrically opposed pairs of clusters. The pairs of clusters are burned and separated in a staging sequence until the final stage is reached. In the presently preferred embodiment, there are three pairs of engine clusters arranged in a hexagonal configuration about the central pod and each engine cluster contains seven identical engines. The engines are made from light-weight, low-cost materials, without gimbals or other moving parts. Steering of the vehicle is effected by differential control of the engine thrusts of selected engines, using duty-cycle modulation of a plurality of on/off propellant supply valves and, additionally, control of other on/off valves controlling the supply of an inert cryogenic fluid to secondary injection ports on the engine.

Abstract: A technique for maintaining a satellite in an assigned orbit without control or intervention from the ground. Autonomously obtained navigational data provide a measurement of the actual orbit in which the satellite is traveling. So long as the measured orbit conforms to a desired orbit to within a preselected tolerance, periodic corrections of equal magnitude are made to the satellite's velocity, based on a prediction of the effect of atmospheric drag on the orbit. Measurement of the orbit is made by observation of the time that the satellite passes a reference point in the orbit, such as by crossing the ascending node. If the measured orbit departs from the desired orbit by more than the preselected tolerance, a velocity correction of a magnitude different from the one based on prediction is applied to the satellite. For a decaying orbit, the magnitude of the velocity correction is increased above the correction value based on prediction.

Abstract: A technique for maintaining a satellite in an assigned orbit without control or intervention from the ground. Autonomously obtained navigational data provide a measurement of the actual orbit in which the satellite is traveling. So long as the measured orbit conforms to a desired orbit to within a preselected tolerance, periodic corrections of equal magnitude are made to the satellite's velocity, based on a prediction of the effect of atmospheric drag on the orbit. Measurement of the orbit is made by observation of the time that the satellite passes a reference point in the orbit, such as by crossing the ascending node. If the measured orbit departs from the desired orbit by more than the preselected tolerance, a velocity correction of a magnitude different from the one based on prediction is applied to the satellite. For a decaying orbit, the magnitude of the velocity correction is increased above the correction value based on prediction.

Abstract: A method and corresponding apparatus for providing spacecraft attitude, position and orbit data without the need for externally supplied data. Using onboard observations of the earth, sun and moon, the system determines spacecraft attitude, instantaneous position, and the orbit based on multiple position estimates. Position and orbit data are derived by multiple deterministic solutions, including some that employ star sensors and gyros, and the multiple solutions are accumulated in a Kalman filter, to provide continuous estimates of position and orbit for use when the sun or moon is not visible. The best estimate of position is selected from the multiple deterministic solutions and the Kalman filter solution, and can be used to control the spacecraft in various ways, without having to rely on ground-based equipment or other spacecraft for the determination of position and orbit.