Abstract: New crosslinked 1,2,4-oxadiazole elastomers have been prepared by thermally condensing (a) monomer having the formula H.sub.2 N(HON)C--R--Q, wherein Q is a triazine rig-forming group such as nitrile or amidine or a mixture of such group with amidoxime, or (b) a mixture of said monomer with R[C(NOH)NH.sub.2 ].sub.2, with R in these formulas standing for a bivalent organic radical having the formula--(CX.sub.2).sub.p --, or --CFY(OCF.sub.2 CFY).sub.m O(CX.sub.2).sub.p O(CFYCF.sub.2 O).sub.n CFY--wherein X is fluorine or hydrogen, Y is fluorine or trifluoromethyl, p ranges from 1 to 18, and m+n ranges from 2 to 7. In the monomer charge, the overall proportions of amidoxime groups to triazine ring-forming groups varies depending on the extent of crosslinking desired in the final polymer.

Abstract: The object of this invention is to provide the method of altering the size of tetrafluoroethylene tubing which is only available in limited combination of wall thicknesses and diameter. The method includes the steps of sliding the tetrafluoroethylene tubing (12) onto an aluminum mandrel (20) and clamping the ends of the tubing to the mandrel by means of clamps (24). The tetrafluoroethylene tubing and mandrel are then placed in a supporting coil (25). The supporting coil with the mandrel and tetrafluoroethylene tubing are then positioned in a insulated steel pipe (28). The steel pipe is normally covered with a fiber glass insulator to smooth out temperature distribution therein. The entire structure is then placed in an oven which heats the tetrafluorethylene tubing which is then shrunk by the heat to the outer dimension of the aluminum mandrel. After cooling the aluminum mandrel is removed from the newly sized tetrafluoroethylene tubing by a conventional chemical milling process.

Abstract: A broadband adaptively controlled polarization separation network. Two transmitted signals vertically and horizontally polarized are received as elleptically polarized signals. One of the two received elliptically polarized signals is automatically adjusted to make it linear and thereafter automatically adjusted to make it vertical. If the other signal does not have any vertical polarization on it then the two signals are easily separated and nothing else is needed. However, if there is any vertical polarization on the other signal this invention provides for separating the resulting crosstalk between the two signals. This is done automatically by the use of two sets of crosscouplers which couple a single line to the other line to complete the polarization decoupling operation.

Abstract: A correlated quadruple sampling processor for improved signal-to-noise ratio in the output of a charge-coupled device (CCD) is comprised of: switching means for momentarily clamping a CCD signal line at a first reference level A before a CCD data pulse and then obtaining a first data sample B with respect to the reference A during a CCD data pulse, and storing the positive sample B-A; switching means for momentarily clamping the CCD signal line a second time at the level C during the presence of the CCD data pulse and then obtaining a second data sample D with respect to the reference level C after the CCD data pulse, and storing the negative sample D-C; and means for obtaining the difference between the stored samples +(B-A) and -(D-C), thus increasing the net signal amplitude by a factor of about 2 while the noise would be increased by only a factor of .sqroot.2 since there will be no correlation in the noise between the double samples +(B-A) and -(D-C) effectively added.

Abstract: A magnetic amplifier having two saturable reactor cores with a separate excitation winding on each connected in series opposition, a common control winding and a common output winding, is adapted for use as a low level signal transducer by exciting the separate excitation windings in push-pull mode through a center tapped transformer, and including at least one diode in series with a load resistor connected to the output winding. A resistor in series with the output winding and load resistor is connected between the center tap of the excitation transformer and the connection between the two excitation windings of the saturable cores. This series resistor provides a return current path for the output winding and allows the excitation windings of the saturable cores to operate as primary windings of transformers.

Abstract: A new and improved method for applying photographic resists to otherwise incompatible substrates, such as, for example, a baking enamel paint surface, is described wherein the uncured enamel paint surface is coated with a non-curing lacquer which is, in turn, coated with a partially cured lacquer. The non-curing lacquer adheres to the enamel and a photo resist material will satisfactorily adhere to the partially cured lacquer. Once normal photo etching techniques are employed the lacquer coats can be easily removed from the enamel leaving the photo etched image. This invention is particularly applicable to preparation of edge-lighted instrument panels. In such case a coat of uncured enamel is placed over the cured enamel followed by the lacquer coats and the photo resists which is exposed and developed in the normal way. Once the uncured enamel, now having had the image etched upon it, is cured, the lacquer coats are removed leaving an etched panel.

Abstract: A spine immobilization method and apparatus are provided which make use of a normally flat, flexible bladder filled with beads or micro-balloons that form a rigid mass when the pressure within the bladder is decreased below ambient through the use of a suction pump so that the bladder can be conformed to the torso of the victim and provide the desired restraint. The bladder is strapped to the victim prior to being rigidified by an arrangement of straps which avoid the stomach area. The bladder is adapted to be secured to a rigid support, i.e., a rescue chair, so as to enable removal of a victim after the bladder has been made rigid. A double sealing connector is used to connect the bladder to the suction pump and a control valve is employed to vary the pressure within the bladder so as to soften and harden the bladder as desired.

Abstract: A pilot controlled stability control system that employs direct lift control (spoiler control) with elevator control to control the flight path angle of an aircraft. A computer on the aircraft generates an elevator control signal and a spoiler control signal, using a pilot-controlled pitch control signal and pitch rate, vertical velocity, roll angle, groundspeed, engine pressure ratio and vertical acceleration signals which are generated on the aircraft. The direct lift control by the aircraft spoilers improves the response of the aircraft flight path angle and provides short term flight path stabilization against environmental disturbances.

Abstract: A system is described for guiding a claw to the proper distance and into the proper orientation in yaw and pitch, to engage a grappling fixture. The system includes four proximity sensors on the claw, that are arranged at the corners of an imaginary square, which sense the distance to the top surface of the grappling fixture. If a pair of sensors at opposite corners of the square sense a different distance to the top surface of the grappling fixture, then it is known that the claw is rotated about a corresponding axis with respect to the plane of the grappling fixture.

Abstract: The present invention is in the field of collapsible structural members. It discloses a foldable beam possessing superior qualities of: light weight, compactness for transportation, quick deployment with minimum use of force, and high strength. These qualities are achieved through the use of a series of longitudinally rigid segments, hinged along one side and threaded by one or two cables along the opposite side. Tightening the cables holds the beam extended. Loosening the cables permits the segments to fold away from the threaded side. In one embodiment the segments are connected by canted hinges with the result that the beam may be folded in a helix-like configuration around a cylinder. In another embodiment the segments themselves may be hinged to fold flat laterally as the beam is folded, resulting in a configuration that may be helixed around a shorter cylinder.

Abstract: A self-stabilizing radial face seal comprising an axial member, a primary seal ring juxtapositioned to a seal seat, at least one of said primary seal ring and seal seat being affixed to said axial member so as to rotate therewith, said primary seal ring having a front face which opposes a face of said seal seat, said seal having both high-pressure and low-pressure regions of fluid, said seal seat being provided with a porous ring-like circumferential structure in the face of said seal seat opposite said front face of said primary seal ring.

Abstract: A multifrequency, broadband, dual-polarized corrugated conical horn antenna is simultaneously fed a multiplicity of signals, two for each of five frequencies, with each of a pair of signals fed in each of two orthogonal planes for excitation of a desired spherical hybrid mode (HE.sub.11). The lowest frequency is fed into the horn through orthogonal pairs of colinear slots, each pair being fed by coaxial tee power dividers. Other signals are fed through a circular waveguide connected to the vertex. Band reject cavities block the next higher frequency from passing through the low frequency feed slots. The highest frequency signals are fed through orthogonal ports near the far end of the circular waveguide. The intermediate frequency signals are fed through orthogonal ports spaced along the waveguide.

Abstract: A hot gas engine, such as a Stirling engine, which comprises a displacer portion and an expander portion with a heat exchanger connected therebetween. The expander portion has an expander piston which is operatively connected to and rotates an expander crankshaft. In like manner, the displacer portion is provided with a displacer piston which is also operatively connected to and rotates with a separate displacer crankshaft. The two crankshafts are synchronized with respect to each other, preferably by means of an idler gear. Banks of displacer pistons can also be provided for operation on a common displacer crankshaft and banks of cooperating expander pistons also can be provided for operation on a common expander crankshaft.

Abstract: A Stark effect spectrophone is provided using a pulsed or continuous wave laser (33) having a beam with one or more absorption lines of a constituent of an unknown gas. The laser beam is directed through windows (31,032) of a closed cell (30) while the unknown gas to be monitored is caused to flow continuously through the cell between electric field plates (34, 35) disposed in the cell on opposite sides of the beam path through the cell. The plates are so disposed as to be divergent, e.g., flat plates at an oblique angle relative to each other, or plates shaped according to a mathematical function so that, with constant voltage applied across the plates, there is a linear variation in electric field strength along the beam path. Discrete pressure transducers (37) are positioned at field strength points of interest.

Abstract: Light absorbing ultra-thin films mounted under a fixed strain exhibit the behavior of an optomechanicalor photomechanical transducer. The transducer responds to light in a quick and reversible manner converting a time-variable light source into a time-variable mechanical stress easily monitored by a device such as a strain gage.

Abstract: An improved motor speed and torque controller for brushless DC motors which provides an unusually smooth torque control arrangement. The controller provides a means for controlling a current waveform in each winding of a brushless DC motor by synchronization of an excitation pulse train from a programmable oscillator. Sensing of torque for synchronization is provided by a light beam chopper mounted on the motor rotor shaft. Speed and duty cycle are independently controlled by controlling the frequency and pulse width output of the programmable oscillator. A means is also provided so that current transitions from one motor winding to another is effected without abrupt changes in output torque.

Abstract: Disclosed is a urine collection device for females comprising a collection element defining a urine collection chamber and an inlet opening into the chamber and adapted to be disposed in surrounding relation to the urethral opening of the user. A drainage conduit is connected to the collection element in communication with the chamber whereby the chamber and conduit together comprise a urine flow pathway for carrying urine generally away from the inlet. A first body of wicking material is mounted adjacent the collection element and extends at least partially into the flow pathway. The device preferably also comprises a vaginal insert element including a seal portion for preventing the entry of urine into the vagina in contact therewith.

Abstract: A compensating linkage for the rotor control system on rotary wing aircraft is disclosed. The main rotor and transmission are isolated from the airframe structure by elastic suspension. The compensating linkage prevents unwanted signal inputs to the rotor control system caused by relative motion of the airframe structure and the main rotor and transmission.

Abstract: Current spikes in a buck power converter due to commutating diode turn-off time is eliminated by using a tapped inductor in the converter with the tap connected to the switching transistor, without the commutating diode in the usual place, and instead connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistor is not conducting. In the case of a converter having a center-tapped (primary and secondary) transformer between two switching power transistors operated in a push-pull mode and two rectifying diodes in the secondary circuit, current spikes due to transformer saturation are also eliminated by using a tapped inductor in the converter with the tap connected to the rectifying diodes and a diode connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistors are not conducting.

Abstract: New crosslinked 1,2,4-oxadiazole elastomers have been prepared by thermally condensing (a) monomer having the formula H.sub.2 N(HON)C-R-Q, wherein Q is a triazine ring-forming group such as nitrile or amidine, or (b) a mixture of said monomer with R[C(NOH)NH.sub.2 ].sub.2, with R in these formulas standing for a bivalent organic radical having the formula--(CX.sub.2).sub.p --, or --CFY(OCF.sub.2 CFY).sub.m O(CX.sub.2).sub.p O(CFYCF.sub.2 O).sub.n CFY--wherein X is fluorine or hydrogen, Y is fluorine or trifluoromethyl, p ranges from 1 to 18, and m+n ranges from 2 to 7. In the monomer charge, the overall proportions of amidoxime groups to triazine ring-forming groups varies depending on the extent of crosslinking desired in the final polymer.The heat and chemical resistant elastomers disclosed can serve, for instance, as adhesives, caulking compounds, channel sealants, fuel tank liners.