Abstract: A broadband flared slot notch antenna combined with an overhead metal plate resulting in an improved front-to-back ratio and a reduced response to crossed polarized radiation. The antenna is provided by a metal layer deposited on a dielectric substrate which is etched to form a pair of symmetrical slot sections having facing edges which increasingly curve away from each other to a maximum spacing point which is the antenna aperture. A linking slot interconnects the slot sections at a feed point spaced from the aperture. High frequency electrical voltage applied at the feed point achieves launch of an electromagnetic wave from the aperture. The overhead metal plate is parallel and closely spaced above and shorted to the antenna thereby reducing radiation emissions that are not in the direction of that launched from the aperture.

Abstract: Microgravity sensitive payloads placed on a platform are isolated from external acceleration forces over extended periods of time in the weightless environment inside an orbiting space vehicle by canceling acceleration on the platform. Wide gap dual axis magnetic actuators and accelerometer pairs are spaced about the platform with the magnetic actuators providing a non-contacting magnetic position control, wherein physical contact with the platform is avoided. Position sensors sense platform positioning and the control system, containing both digital and analog computers, controls the magnetic actuators to ensure proper positioning and neutralize any transient acceleration forces applied to the platform.

Abstract: A piezoelectric actuator includes a plurality of linearly axially expandable hard piezoelectric rods located between two plates and are distributed about a central twistable core fastened between the plates, with the axis of the rod skew to the axis of the core, resembling a squirrel cage. The actuator produces a twisting movement between the plates, responsive to voltage induced expansion of those piezoelectric rods. Fly by Wire aircraft control is realized with the actuator in various systems providing all electric control of aerodynamic surfaces, including an electronic helicopter swashplate by which the effective pitch of the main rotor blade is controlled.

Abstract: A solid rocket fuel is formed by mixing a liquid hydroxyl terminated prepolymer such as polybutadiene, with hexamethylenetetramine, and adding a cross-linking agent, particularly a multifunctional isocyanate. The mixture is poured or cast into a mold, cartrige, or insulated motor case and cured, preferably at ambient temperature. The hexamethylenetetramine is employed as the major fuel component in an amount in the range of about 60 to about 83% based on the total weight of the fuel. The preferred curing or cross-linking agent is a liquid multifunctional isocyanate. Processing aids and/or mechanical property modifiers can be added in minor amounts.

Abstract: Microwave devices incorporate at least one photosensitive baffle that is selectively illuminated changing the baffle's electronic characteristic from being transparent to being reflective of microwave energy. The baffle serves as a gate, tuning element, reflector and the like. Various forms of photosensitive baffles and microwave devices are presented.

Abstract: A perforated sheet is diffusion bonded to a thin solid sheet. Each of the perforations of the perforated sheet is tapered, having a maximum diameter at the surface that is not bonded to the thin sheet and a smaller diameter at the surface that is bonded to the thin sheet. The bonded perforated sheet and thin sheet are included with other solid metallic sheets in a forming pack to be superplastically deformed into a structure. The bonded perforated sheet and thin sheet are placed on the top of the forming pack so that the thin sheet will face outwards after the structure is formed. After the superplastic deformation process is completed, the thin sheet is removed by machining to expose the perforated sheet and provide a structure for controlling laminar flow over the perforated sheet. The exposed surface of the perforated sheet includes the smaller diameter of each tapered perforation, while the inner-facing or blind surface of the sheet includes the maximum diameter.

Abstract: A power system provides various levels of electrical power at various radio frequencies to specific input locations of a neutral particle beam accelerator system. Both the power system and the accelerator system are mounted on a space platform. The power system includes separate modules mounted on two hinged members of the platform. The modules utilize turbines, generators and fuel cells to provide the needed electrical power which is amplified to the desired levels required by the accelerator system. In addition, a fuel cell is utilized to power a pulse drive motor to drive the generators during turbine start up in order to provide high voltage output power during the start up. A regenerator produces hydrogen and oxygen from the water effluent produced by the fuel cells and the combustors which powers the turbines thereby recycling the fuel and working fluid and consequently making the power system generally non-contaminating and fuel efficient.

Abstract: A robot comprised of a platform, tendons and a control system. The platform contains proximal reels for the storage, retraction and extension of the tendons, with each tendon having a reel. The distal ends of the tendons are anchored at separate locations. The work space of the robot is primarily determined by the location of the tendon anchors, although it can be expanded by having pairs of tendons cross each other in between the platform and their distal anchor points. The platform is translated and rotated in the work space by controlling the lengths of the tendons extending from their respective reels. A master computer located on the platform controls each reel and coordinates their actuation. When used with at least six tendons and reels, the platform has six degrees of freedom: translation in three axes and rotation about each of the foregoing three axes. Numerous types of end effectors can be mounted on the platform, thus enabling the robot to perform a wide variety of tasks.

Abstract: A relatively impervious mechanical seal is formed between the outer surface of a tube and the inside surface of a mechanical fitting of a high pressure fluid or hydraulic system by applying a very thin soft metal layer onto the outer surface of the hard metal tube and/or inner surface of the hard metal fitting. The thickness of such thin metal layer is independent of the size of the tube and/or fittings. Many metals and alloys of those metals exhibit the requisite softness, including silver, gold, tin, platinum, indium, rhodium and cadmium. Suitably, the coating is about 0.0025 millimeters (0.10 mils) in thickness. After compression, the tube and fitting combination exhibits very low leak rates on the order or 10.sup.-8 cubic centimeters per second or less as measured using the Helium leak test.

Abstract: Placed in electrical circuit in shunt of the electrodes that supply current to a protected device and optically coupled to the location in the protected device where an electric arc is most likely to occur, a photosensitive device, responsive to illumination created by such an electric arc, switches to a conductive state, thereby short circuiting the electrodes feeding current to the arc and the arc is quickly extinguished.

Abstract: A solid rocket fuel formed by mixing a liquid hydroxyl terminated prepolymer such as polybutadiene, with hexamethylenetetramine, and adding a cross-linking agent, particularly a multifunctional isocyanate. The mixture is poured or cast into a mold, cartrige, or insulated motor case and cured, preferably at ambient temperature. The hexamethylenetetramine is employed as the major fuel component in an amount in the range of about 60 to about 83% based on the total weight of the fuel. The preferred curing or cross-linking agent is a liquid multifunctional isocyanate. Processing aids and/or mechanical property modifiers can be added in minor amounts.

Abstract: Single expansion ramp to extend from the exhaust opening of a fluid nozzle. A surface of the ramp lying adjacent to fluid flow exhausting the nozzle is porous. The ramp of the present invention reduces the shock wave noise resulting from supersonic flow exhausting the nozzle by causing the formation of weak compression waves in the exhaust plume, which in turn weaken the strength of the standing shock waves in the plume.

Abstract: The disclosed invention is a digitally configurable sequential logic circuit which produces serial binary data patterns. The circuit is configured by specifying two non-negative integers A and B. For given values of A and B, the circuit produces a serial binary data pattern with the following properties: 1) in every consecutive (A+B) bits of the pattern, there are A ones and B zeros, 2) the ones in the pattern are maximally spread apart from one another, and 3) the zeros in the pattern are maximally spread apart from one another. The patterns so produced are useful in a variety of applications.

Abstract: This invention discloses a process by which a silicon bipolar transistor can be fabricated having a polysilicon emitter region and a polysilicon base region by a single polysilicon deposition step. After conventional fabrication of the substrate, collector and base layers, a first dielectric layer is deposited over the developing wafer structure. The first dielectric layer is then etched in order to define polysilicon emitter, base and collector regions. Next, a polysilicon layer is deposited over the first dielectric layer and the etched regions. A planarization layer is deposited over the polysilicon layer, and the planarization layer and the polysilicon layer are etched so that polysilicon only remains in the defined polysilicon emitter, base and collector regions. The polysilicon emitter, base and collector regions are then implanted with dopants to provide the appropriate interfaces.

Abstract: A multifunction antenna system is provided which has adaptive beam forming capabilities for transmitting and receiving signals having various beam patterns over a hemispherical field of view. The antenna system includes a beamformer having an array of N spiral arm elements for transmitting and receiving a radiating beam. N analytic voltage signals are produced by the N cylindrically symmetric spiral arm elements in relation to the radiating beam. A beam processor is further provided for selecting the appropriate combination of vector weight coefficients in response to input data. The beam processor loads the selected N vector weights into a vector weighter. In the transmit mode, the vector weighter multiplies the selected vector weights by an input signal to produce the N analytic signals which are then applied to the multiple arm spiral antenna and transmitted therefrom.

Abstract: An N-bit asynchronous successive approximation analog-to-digital converter is provided for converting an analog signal to a binary coded representation thereof. The analog-to-digital converter employs N inverting amplifiers. Each of the inverting amplifiers receives a scaled analog input signal and provides a one bit output of the binary coded output. The scaled analog input signal applied to each inverting amplifier includes an analog input signal and feedback signals from each of the inverting amplifiers which provide a more significant output bit of the binary coded output. Each inverting amplifier thereby provides an output dependent upon the amplifier's threshold voltage which output provides one bit of the binary coded representation. In addition, each inverting amplifier may further be adapted to receive a reference signal.

Abstract: Apparatus, and a related method for its operation, for integrating selected multiple assembly and repair operations of electronic component packages, such as printed wiring board assemblies (PWBAs), at a single multi-function workstation. Each PWBA product is uniquely identified by a bar code or similar inscription, and the identification permits product data to be retrieved from a factory or depot database. The retrieved product data controls the various operations to be performed, such as positioning and soldering of surface-mounted components, inspection for defects, desoldering of defective components, and reinstallation of replacement components.

Abstract: A switching system comprised of input, intermediate and output switch matrices. There are r n.times.m input matrices, r m.times.n output matrices with m r.times.r intermediate switching matrices. Signals are switched from inputs at the input matrices through the intermediate switch matrices and are output through the output matrices.

Abstract: A thin film resistor with an insulating layer disposed between a substrate material and a resistor material is disclosed. Also, disclosed is a technique for fabricating this thin film resistor. In accordance with the preferred embodiment, the thin film resistor employs an insulating layer of silicon nitride with a thickness of 2000 .ANG.. The insulating layer prevents the resistor layer from diffusing into the substrate material which, in turn, significantly reduces variations in the resistor value during accelerated life testing. Compared to thin film resistors with a resistor layer evaporated directly upon a substrate material, reliability is increased from a few hundred hours up to thousands of hours. Also, the maximum current handling capability is increased by greater than one order of magnitude, which results in a thin film resistor which requires less surface area of a wafer.

Abstract: A small, high performance MMIC compatible filter having a suspended dielectric substrate transmission medium to achieve superior Q. The substrate is suspended within an opening formed in a surrounding housing and has a plurality of conductive paths disposed thereon. An elliptical function response provides optimum filter size and insertion loss for a given required out-of-band rejection by making use of finite transmission zeroes on each side of the passband.