Abstract: Cryogenic foam insulation 20 is adhesively bonded to the outer wall of the fuel tank structure 10. The cryogenic insulation 20 includes square sheets 12 fabricated from an array of abutting blocks 14. Each block 14 includes a sheet of glass cloth 18 adhesively bonded between two layers of polymethacrylimide foam 16. Each block is wrapped in a vapor impermeable membrane 24, such as a polyimide-aluminum-polyimide composite laminate, to provide a vapor barrier. Very beneficial results are obtained by employing the present invention in conjunction with fibrous insulation 28 and an outer aeroshell 30, which is a hot fuselage structure having an internal thermal protection system.

Abstract: Methods are described for rapidly damping oscillation of an acoustically levitated object or for causing and maintaining such oscillations, and a method is provided for determining the restoring force constant K on the levitated object by measuring its frequency of oscillation. Oscillations of a levitated object are damped by applying levitating acoustic energy at a frequency slightly less than the center resonant frequency. Oscillations are maintained by applying acoustic energy slightly greater than the center resonant frequency. The restoring force constant of the levitation force is proportional to square of the frequency of oscillation of the object.

Abstract: The synthesis and characterization of several polyenamine ketones are discussed wherein conjugated diacetylenic diketones and aromatic diamines are used as a route to the formation of high molecular weight polyenamine ketones which exhibit good mechanical properties and can be cast into creasible films. Typical polymerization conditions involved the reaction of stoichiometric amounts of 1,4- or 1,3-PPPO and a diamine at 60.degree.-130.degree. C. in m-cresol at (w/w) solids content of 8-26% for a specified period of time under a nitrogen atmosphere. Novel polyenamine ketones were prepared with inherent viscosities as high as 1.99 dl/g and tough, clear amber films with tensile strengths of 12,400 psi and tensile moduli of 397,000 psi were cast from solutions of the polymers in chloroform. The polymers exhibited T.sub.g s as high as 235.degree. C. and weight losses of 14% after aging at 232.degree. C. in circulating air for sixty hours.

Abstract: A zero-leak cryogenic coupling includes a polymeric seal clamped to a male bayonet member with two pairs of tightening rings. The tightening rings threadably engage each other in respective pairs around tapered ends of the inflatable seal member so that a wedging action tightens the seal member about the male bayonet. Once in place, the seal may be inflated via an inflation port so that its expansion provides a pressure contact with the inside surface of a coaxial female member.

Abstract: An optical processor is provided which facilitates selection of any of a variety of patterns or images which are to be compared with a Fourier transform of a template image, wherein the processor can be constructed at low cost. One of the two images that are to be compared is formed by generating video signals representing the image and using those signals to drive a liquid crystal array through which light passes.

Abstract: A dual refrigeration system for cooling a sink device is described, which automatically thermally couples the cold refrigerator to the sink device while thermally isolating the warm refrigerator from the sink device. The system includes two gas gap heat switches that each thermally couples one of the refrigerators to the sink device, and a pair of sorption pumps that are coupled through tubes to the heat switches. When the first refrigerator (18) is operated and therfore cold, the first pump (50) which is thermally coupled thereto is also cooled and adsorbs gas to withdraw it from the second heat switch (44), to thereby thermally isolate the sink device (12) from the warm second refrigerator (26). With the second refrigerator being warm, the second pump (52) is also warm and desorbs gas, so the gas lies in the first switch (38), to close that switch and therefore thermally couple the cold first refrigerator (18) to the sink device.

Abstract: An erectable manipulator placement system for use on a space station and comprising an elongate lattice-like boom having dual guide tracks attached to parallel chords thereof, a carriage-like dolly movable along said tracks, and a segmented maneuvering arm-like assembly pivotally mounted on and extending from said dolly. The system further includes a turntable base pivotally interconnected with the proximal end of the boom and positioned either on a part of a transferring vehicle, or on another payload component being carried by said transferring vehicle, or on the space station.

Abstract: A steerable multibeam five element cross-feed cluster antenna (16) system. The feed power is divided into five branches. Each branch includes a switching network (12A-12E) comprised of a plurality of time delay elements (90A; 92A) each individually controlled by a respective electromagnetic latching switch (56A,B; 58A,B; 60A,B; 62A,B; 46A,B). Frequency independent individual two-dimensional beam steering at IF scanning frequencies is thereby provided wherein discrete incremental time delays are introduced by the switching networks into each branch and the signals recombined thereafter to form each beam. The electromagnetic latched switching reduces power consumption and permits higher power switching and reciprocal coincident transmit and receive operation. Frequency independence due to incremental time delay switching permits coincident reciprocal operation and steering for transmit-receive signal paths carrying different transmit-receive frequencies.

Abstract: Apparatus is provided which greatly reduces the intensity of bright portions of an image while only moderately reducing the brightness of dimmer portions of the image, to thereby compress the range of light intensities to facilitate detection of the image. The apparatus includes a light detector device formed by a chip of photorefractive material. A two-dimensional array of light beams from an object to be detected, passes through a beam splitter to form two arrays of light beams. The two arrays of light beams are directed at different angles against a surface of the chip of photorefractive material, the two arrays of light beams forming coincident images on the surface. One of the two-dimensional arrays of beams emerging from an opposite surface of the chip has a lower range of intensities, to facilitate detection of the object despite very bright spots on its image. The other array of light beams energing from the chip has a greater range of intensities than the unprocessed image of the object.

Abstract: A tapered tubular polyester sleeve as set forth. It has a large end 12 and a small end 14 with a length to be determined. The ratio of taper is also determined by scale factors. All the warp yarns extend to the large end 12. A requisite number of warp yarns 16 extend the full length of the sleeve. Other warp yarns exemplified at 18, 22, 26, 28, 30 and 32 extend from the large end but are terminated along the length of the sleeve. It is then woven with a filling yarn 40 which extends in a full circle along the full length of the sleeve to thereby define the tapered sleeve. The sleeve after fabrication is then placed on a mandrel 42, heated in an oven 44 and is thereafter placed on the arm or other limb of a space suit exemplified at 50.

Abstract: A corrugated panel structure for supporting compressive loads includes curved cap strips 22 separated by truss-core web segments 30. The truss-core web segments 30 are formed from first and second flat panels 32 and 34 with a corrugated filler 36 therebetween. The corrugated filler 36 extends in the direction of the compressive load, thereby providing load carrying capability for the compressive load. As a result, all components of the panel structure have a compressive load carrying capability resulting in a high strength-to-weight ratio when the compressive load is limiting.

Abstract: An isolator is provided which has an inlet at ground electrical potential which receives gas, and which has an outlet at a high electrical potential through which gas is discharged, the isolator being compactly and simply constructed while providing a long narrow path that minimizes the possibility of electrical breakdown through the gas. The isolator includes a first element forming a cylindrical core and a cup-shaped second element forming a sleeve portion that closely receives the core. The core has a helical groove on its outside to form a passage between the groove and the inner walls of the sleeve. The core also has a vertical hole extending to the bottom of the core and a radial groove in the bottom of the core that extends between the hole and the bottom of the helical groove.

Abstract: A gas particle radiator adapted to operate in a microgravity space environment having a transparent boundary which transmits energy in the infrared spectrum, and a gas particle mixture that yields high absorption and emittances.

Abstract: A common hydraulic reservoir holds one or more rows of slidable pistons or "fingers" in a base, or "hand". The individual fingers in each row expose graduated cross-sectional fluid application areas to the hydraulic fluid in the reservoir, with the smallest fluid application area in the center of the row and graduating to progressive larger fluid areas towards both ends of each row. The fingers are elongated pistons. Exposed outer ends of each piston extending away from the reservoir, house a transverse pad to contact an object to be held. The transverse pads are universally ball-joint and spring-center mounted in a longitudinally located opening at the outer tapered end of each finger. Simple and effective capacitance metering in the reservoir is provided for each finger.

Abstract: A digital phase-lock loop (DPLL) which generates a signal with a phase that approximates the phase of a received signal with a linear estimator. The effect of a complication associated with non-zero transport delays related to DPLL mechanization is then compensated by a predictor. The estimator provides recursive estimates of phase, frequency, and higher order derivatives, while the predictor compensates for transport lag inherent in the loop.

Abstract: A porous plug (10) is provided for the reduction or elimination of positive error caused by orifice (20) during static pressure measurements of airfoil (14). The porous plug (10) is press fitted into orifice (20), thereby preventing error caused either by fluid flow (30) turning into the exposed orifice (20) or by fluid flow (30) stagnating at the downstream edge (21) of orifice (20). In addition, porous plug (10) is flushed with the outer surface of airfoil (14), as by filing and polishing, to provide a smooth surface which alleviates error caused by imperfections in orifice (20). Porous plug (10) is preferably made of sintered metal, which allows air to pass through the pores, so that static pressure measurements can be made by remote transducers (not shown).

Abstract: An ultrasonic depth gauge 20 for liquids under high pressure is comprised of a transducer assembly 21 and a supporting electronics unit 22. The transducer assembly is mounted into the bottom wall of a storage vessel 12 with its resonating surface directly exposed to the highly pressurized liquid 13 in the vessel. The transducer assembly consists of a conventional transducer element 38 rigidly bonded to the inside wall of a bored out conventional high-pressure plug 30 thereby forming a composite resonator 50. The element and the plug wall resonate as one upon electrical excitation of the element while the transducer element is completely shielded from any exposure to the liquid under high pressure. The composite resonator sends a vibration up to the surface of the liquid where it is reflected back to the composite resonator. The supporting electronics unit measures the vibration round-trip transit time which is proportional to the depth 15 of the liquid.

Abstract: A passive heat transporting and fluid management apparatus including a housing in the form of an extruded body member having flat upper and lower surfaces is disclosed. A main liquid channel and at least two vapor channels extend longitudinally through the housing from a heat input end to a heat output end. The vapor channels have sintered powdered metal fused about the peripheries to form a porous capillary wick structure. A substantial number of liquid arteries extend transversely through the wicks adjacent the respective upper and lower surfaces of the housing, the arteries extending through walls of the housing between the vapor channels and the main liquid channel and open into the main liquid channel. Liquid from the main channel enters the artery at the heat input end, wets the wick and is vaporized. When the vapor is cooled at the heat output end, the condensed vapor refills the wick and the liquid reenters the main liquid channel.

Abstract: A dc power supply for spacecraft arcjet thrusters has an integral automatic starting circuit and an output averaging inductor. The output averaging inductor, in series with the load, provides instantaneous current control, and ignition pulse and an isolated signal proportional to the arc voltage. A pulse width modulated converter, close loop configured, is also incorporated to give fast response output current control.

Abstract: A method is provided to bond strain gauges 6 to various materials. First, a tape 9 with an adhesive backing 10 is placed across the inside of fixture frame 8. Strain gauge 6 is flatly placed against adhesive backing 10 and coated with a thin, uniform layer of adhesive 5. Tape 9 is then removed from fixture frame 8 and placed, strain gauge side down, on the material to be tested. If the material is a high reluctance material 12, induction heating source 20 is placed upon tape 9. If the material is a low reluctance material 13, a plate 23 with a ferric side 21 and a rubber side 22 is placed, ferric side down, onto tape 9. Induction heating source 20 is then placed upon rubber side 22. If the material is an insulator material 14, a ferric plate 7 is placed on tape 9. Induction heating source 20 is then placed on ferric plate 7.