Abstract: A passive ranging system is disclosed wherein the transducer array has its eam pattern modulated so as to match the arrival angles of the different wave fronts arriving at the array from various target distances. The beams are formed by orientating a multiplicity of readout arms at appropriate angles with respect to a recording medium which has the individual signals detected by each transducer of the array recorded thereon in different horizontal tracks. The readout arms thus simultaneously scan all of the signals associated with the arrival angles for a particular range and produce a signal whose amplitude is a measure of the probability of a target at this range.

Abstract: A blade control method and means for helicopter rotors which increases heopter speed by mixing two/rev. control motion with one/rev. cyclic and collective motion through mechanical summation is provided. Both rotary and vertical motions are imparted to an inner control shaft and these motions are combined to impart vertical oscillatory motions to the rotor head which motions increase the thrust developed by the helicopter rotor.

Abstract: High power, phase coherent pulses are generated by superconducting appara which includes a superconducting cavity resonator that is pumped by a low power microwave source while being isolated from a load. Switching of the cavity to an emitting mode is accomplished in 5 to 10 nanoseconds by firing a gas discharge tube that acts to couple the activity to the load while decoupling it from the pumping source.

Abstract: A flexible, low-density piezoelectric transducer utilizing a PZT-polymer posite that is formed with the two phases three-dimensionally interpenetrant. The ceramic PZT microstructure, which is produced by a replication process that in one embodiment reproduces the structure of a coral species, is filled with silicone rubber and thereafter its transverse connectivity is broken by a light shearing deformation to give it flexibility.

Abstract: A method and means for continuously returning degassed and de-emulsified uid metal to the collector sites of high speed acyclic generators is provided. Hydrodynamic pressures developed by the high speed rotating discs are employed to pump liquid current-carrying metal through a plurality of stationary passageways into an interiorly positioned rotating cup or channel where centrifugal forces return purified metal to the collector sites and retain the impure liquid metal.

Abstract: A device for generating an air jet without the use of moving parts is proed. High voltage is used to create a corona discharge electric wind in a ducted, compact, portable generator that can be used for augmentation cooling applications where high voltage is available.

Abstract: A wide bandwidth interferometer which may be employed in a guidance system or a rolling missile delays the radar signals detected by one of the antennas by a fixed amount and the signals detected by the other antenna by a variable amount prior to their multiplication in a device which first advances the phase of one of the signals by 90.degree.. The product signal, which is proportional to the sine of the angle between the rolling axis and the line-of-sight to the target, is integrated in a limited-integrator whose output is summed with a pick-off signal from an onboard gyroscope. The sum signal determines the amount of the variable delay, while the output of the integrator controls the gyroscope to align it with the radar signal direction and the missile steering apparatus to home it on target.

Abstract: A means for interfacing between low pressure, low flow fluidic circuits and he high pressure, high flow input requirements of fluidic digital thrusters to control the roll, pitch or yaw rate of missiles is provided. Input pressures from the fluidic circuitry cause a fluidic digital amplifier to go to one of its two stable states. The output from the digital amplifier operates one piston in the interface means, causing it to close off a digital thruster control port. The same output is ported to the opposite side of the other interface means piston, causing it to unblock the other digital thruster control port. Blocking of the first control port causes the digital thruster to switch to either a left or right output leg to initiate a corrective thrust. The pistons are interlocked so that only one piston can be extended to cover a given control port at any time.

Abstract: A process for producing a bond at the interface between an encapsulant and he object to be encapsulated is provided. A selected resin with curing agent is coated and oven cured on the object to be encapsulated and thereafter a copolymer coating is applied to the assembly in a fluidized bed and the assembly is oven cured. The resulting product is then injection molded with a suitable polyethylene material.

Abstract: A CO.sub.2 -powered system for cooling garments by conduction cooling when he wearer is subjected to heat stress is provided. A dry ice refrigerant source provides the cooling and the CO.sub.2 gas given off during sublimation of the dry ice provides the motive power for a diaphragm type pump which transports heat transfer liquid between the heat source and the refrigerant or heat sink. The system may be interfaced with brine type cooling systems used for food preservation to maintain food temperatures under emergency conditions such as power outages due to its non-electrical energy source.

Abstract: A method of and means for introducing a heated liquid into a cold liquid the purpose of improving the pumping rate of the cold viscous liquid is provided. The heated liquid is directed upward into the suction inlet of the cold liquid pump through an orifice or a multiplicity of small orifices which are disposed a selected distance below the suction inlet.

Abstract: 1. A system for coding optical images comprising, in combination, first and second geometric arrays of light-conducting elements, similar elements of each array being scrambled in a random fashion such that the respective ends of these conductors occupy different relative positions at both ends of the array, said arrays being coupled end to end, and means for varying the position of one of said arrays with respect to the other whereby an image passing through said arrays is subjected to different coding in each of said arrays.

Abstract: An optical homodyne microscope is disclosed which detects phase modulation of the optical radiation that is reflected from an object under study which is in a state of periodic motion. The dimensions of the object may be smaller than the optical wavelength with this technique. By analyzing the resultant phase modulation spectrum, information concerning the shape of the object can be obtained.

Abstract: A picosecond pulse generator for producing pulses having widths in the or of 10.sup.-12 seconds utilizes a Josephson junction that has an external load resistor connected in shunt therewith by a balanced transmission line. The Josephson junction is driven by a high frequency oscillator, and the AC current, I.sub.1, flowing through it is adapted to have its amplitude varied with respect to I.sub.c, the critical current of the junction. As the value of I.sub.1 /I.sub.c exceeds one and increases, first a single and then an increasing number of picosecond pulses are produced during each half cycle of the high frequency oscillator.

Abstract: An offset or asymmetrical self-contained liquid metal current collector for cyclic or homopolar electrical generators or motors is provided which includes a narrow annular volume on one side and a wide annular volume on the other side of the collector disc. Selectively positioned circular troughs effectively communicate with each other so that the liquid metal is trapped and retained when the rotating speed of the disc is too low to centrifugally maintain the liquid metal at the outer periphery of the disc.

Abstract: Radar wave energy entering aircraft engine cavities is substantially disped by providing within such cavities surfaces having perturbations or dipoles which interact with the electromagnetic energy within the cavity interior, causing the reflected energy to be defocused or scattered over a broad range of angles thereby substantially lowering the radar cross section of the cavities.

Abstract: A simply constructed low input power cyclic cryogenic refrigerator suitable or cooling superconducting quantum interfering devices (SQUID) and similar instruments is provided. A Stirling machine having a multistage displacer and a piston as its only essential moving parts, with helium gas as the working fluid, achieves and maintains a temperature of substantially 8.5.degree. K. The working cylinder and displacer are separated by a tube and are fitted together precisely at steady-state operation rather than at room temperature. The displacer preferably is made of nylon and its cylinder of an epoxy-glass composite to provide the nearly optimum clearance required to maintain the 8.5.degree. K. temperature for continuous periods on the order of several weeks.

Abstract: An arrangement for determining the temperature gradient within a fluid mem, which is used to ascertain the magnitude of vertical water movement, utilizes a pair of thermistors connected in a differential Wheatstone bridge that senses the temperature at two locations. The DC bridge driving voltage has its polarity periodically reversed for equal time intervals by a logic signal. The bridge output signal is converted to a variable frequency and counted during each of these different intervals in opposite directions. This subtraction process, which yields the temperature difference at the two locations, also, among other things, eliminates the effects of drift from the temperature measurement. The system also contains provisions for minimizing any offset caused by changes in the bridge driving voltage, amplifier offset instabilities and variations in other circuit components.

Abstract: A beamformer for wideband signals wherein the elemental signals available the sensors of a receiving array are subjected to Fast Fourier Transformations which decompose them into a plurality of narrowband signals. The narrowband signals, which consist of signals having the same Fourier coefficients, are subjected to appropriate phase shifts to form a plurality of narrowband beams having the directional characteristics desired. Reconstruction of the wideband signal is accomplished by subjecting the narrowband beams to an inverse Fast Fourier Transform. The beamforming is thus performed with narrowband signals, and only phase shift circuits are required.

Abstract: The linearity of a field-effect transistor's logarithmic transconductance extended over an increased range by having its channel non-uniformly doped in a direction along the width of the gate electrode and perpendicular to that of current flow.