Abstract: An adaptive control includes a digital error correction system (DECS) to reduce control system error to near zero by anticipating a problem and feeding forward in time a correction to deal with the problem before it happens. The adaptive control is used in a controlled system of the kind which is cyclical in operation and which operates in response to repetitive cycle commands so that the operation of the system is substantially predictable for a significant number of cycles of operation. The adaptive control is incorporated in a refrigerator system in which two Stirling cycle refrigerators are mounted in opposition to one another. The adaptive control permits accurate control of the command waveform frequency and shape, enables the refrigerator system to be more thermodynamically efficient, and enables the two refrigerators to exactly cancel each other's vibration.

Abstract: A non-pyrotechnic release system for use in satellites and other remote actuations applications is disclosed. This system employs shape memory rod assemblies to release a captive toggle that retains the item to be deployed. The shape memory rod assembly includes an internally installed resistance heating element for heating the rod to cause it to assume its memory shape.

Abstract: An optical signal propagated through a poled-polymer input channel waveguide can be switched to a selected one of a pair of poled-polymer output channel waveguides, while producing only very low cross-talk in the unselected one of the output channel waveguides. The input and output channel waveguides are located within a non-linear optical polymer structure so that an end portion of the input channel waveguide is disposed between end portions of the two output channel waveguides. A first pair of electrodes is positioned so as to apply an electric field across one of the output channel waveguides, and a second pair of electrodes is positioned so as to apply an electric field across the other of the output channel waveguides.

Abstract: The present invention is directed to a vessel that is hull stabilized. The stability is achieved by the particular orientation of the lower hulls. In one embodiment the lower hulls are inclined to the calm water or design waterline.

Abstract: A matrix of infrared generating cells is disclosed. Each cell includes a resistive element formed over and traversing a cavity formed on the surface of the supporting semiconductor substrate.

Abstract: The present invention is directed to a vessel that is form stabilized. The stability is achieved by the particular shape or orientation of the struts or both. In one embodiment the dihedral struts have a cambered cross-section area. In another embodiment the cross-section area of the struts are symetrical and the struts are mounted in a toe out position.

Abstract: The present invention is directed to maneuvering control systems for small waterplane-area twin hull design watercraft. The maneuvering control system of the present invention includes horizontal or dihedral foils mounted on the lower hulls of the watercraft. The foils may take the form of a one-piece rotatable foil or a foil that includes a plurality of movable sections.

Abstract: The disclosed heterodyne measurement apparatus utilizes a single coherent light source to simultaneously measure the location of a number of points on a surface. The coherent light is split into two parts by a Bragg Cell. One part, after being spatially split into a plurality of beams by a second Bragg Cell, fed to a plurality of reflectors on the surface, and recombined by the second Bragg Cell, is heterodyned with the second part. The heterodyned signal is fed to a photodetector and further processed to produce a signal representative to the distance to the points of interest on the surface.

Abstract: Apparatus is shown for substantially increasing the feed rate of pulverized material into a pressurized container. The apparatus includes a rotor that is mounted internal to the pressurized container. The pulverized material is fed into an annular chamber defined by the center of the rotor. A plurality of impellers are mounted within the annular chamber for imparting torque to the pulverized material.

Abstract: Pairs of input transducers are formed on the surface of a piezoelectric crystalline body. The input transducers in each pair produce adjacent parallel surface acoustic waves of opposite polarity and specific phase difference which are sensed by a corresponding output transducer. The input transducers of each pair are offset from one another by amounts related to the wavelength of the surface acoustic wave so that a maximum cancellation of the voltages induced in the output transducers by the acoustic waves can be used to indicate the relative delay or phase difference of signals applied to the input terminals and to do so in a manner which is insensitive to temperature variation from one point to another in the piezoelectric crystal.

Abstract: Apparatus is shown for feeding a slurry to a pressurized housing. An impeller that includes radial passages is mounted in the loose fitting housing. The impeller hub is connected to a drive means and a slurry supply means which extends through the housing. Pressured gas is fed into the housing for substantially enveloping the impeller in a bubble of gas.

Abstract: A device for pressurizing pulverized coal and circulating a carrier gas is disclosed. This device has utility in a coal gasification process and eliminates the need for a separate collection hopper and eliminates the separate compressor.

Abstract: Method and apparatus are shown for the continuous feeding of pulverized material to a high pressure container. A rotor is located within the high pressure container. The pulverized material is fed from a feed hopper through a stationary feed pipe to a vented spin-up chamber to a plurality of two-stage sprues mounted in the rotor. Control nozzles downstream from the sprues meter the flow of coal through the sprues.

Abstract: Method and apparatus are shown for control of continuous feeding of pulverized material to a high pressure container. A rotor is located within the high pressure container. The pulverized material is fed from a feed hopper through a stationary feed pipe to a vented spin-up zone chamber to a plurality of sprues mounted in the rotor. Control of the pressure within control nozzles downstream from the sprues adjusts the flow rate of coal through the sprues.

Abstract: A sensor formed on the surface of a body of piezoelectric material. Two input transducers disposed on the surface in parallel spaced apart relation produce surface acoustic waves in the body in response to the application of signals to the input transducers. A row of output transducers is disposed on the surface between the input transducers. Individual output transducers are offset from one another by amounts related to the wavelength of the surface acoustic wave so that at or near only one of the output transducers will the two surface acoustic waves from the input transducers cancel each other. An analog circuit and a digital circuit for ascertaining which output transducer experiences maximum cancellation to afford a determination of the delay difference between the two signals applied to the input transducers.

Abstract: Apparatus is shown for adjusting the feed rate of pulverized feed material into a pressurized container. The apparatus also has utility for compensating for variations in the permeability of the feed material. A rotor that includes sprues with provision for controlling the pressure distribution along the sprues is located within the pressurized container. The rotor hub is connected to a drive means and a material supply means which extend through the wall of the container. A line for controlling pressure along the sprues by gas injection is connected to a chamber between sections of the sprue for controlling gas pressure at that point. The gas pressure control line is connected to a pressurized gas source and a control system external to the rotor.

Abstract: A subsea drill-thru manifold center for petroleum well completion and production is disclosed. The manifold center is compartmented so each well is within its own gas tight compartment. A removable sleeve through which the well is completed is mounted in each compartment. After each well is completed its sleeve is removable so it can be put in production in the conventional manner.

Abstract: A gauge for measuring the distance and angle between two pipes is disclosed. The gauge consists of an elongated tubular body section adapted to be rigidly affixed to one of the pipes and including an extendable probe. A target plate is fitted over the other pipe and the extendable probe is brought into contact with the target plate. The angle between the target and the extendable probe, the eccentricity of the extendable probe and the target plate and the length of the combination of the tubular body and the extendable probe gives sufficient dimensions for cutting a curved section of pipe or pup.

Abstract: The analog bandwidth compressor of the present system preserves the actual frequencies of the detected signal. This is accomplished by feeding the detected signal to a bank of contiguous filters and feeding the outputs of each of these filters to an AM detector and a frequency divider. The output from each frequency divider is fed to a tunable filter bank. The outputs of the tunable filter bank are fed to multipliers where the outputs from the associated AM detectors are superimposed on the frequency signals from the tunable filter bank. The output of the plurality of multipliers is fed to a summing network which provides a reduced bandwidth signal. The output of the summing network is subsequently fed through a transmission system to a bandwidth restoration circuit which consists of a tunable contiguous filter bank, AM detector, frequency multiplier, tunable filter bank, multipliers and a summer similar to the bandwidth reduction circuit.

Abstract: A digital voice pitch extractor is disclosed that determines the pitch frequency of human speech in real-time or at the same rate as it is uttered. The invention does not need the full bandwidth of the speech signal in order to perform its function. It will accept band-limited signals lacking fundamental pitch energy such as those from telephone channels. The signal can be severely degraded by added noise and the pitch extractor will still reliably determine the pitch.The invention includes a bank of contiguous bandpass filters. The outputs of each of the filters are converted to pulse trains and are summed to form a bi-phase harmonic histogram. The fundamental period is derived from the histogram and is verified by an error correction circuit.The circuit stability and accuracy needed to perform this task is achieved through the use of digital, as opposed to analog, electrical circuits in the main portion of the voice pitch extractor and the use of noise minimizing techniques.