Abstract: The invention relates to a method and apparatus for frequency spectrum analysis of an unknown signal in real time based upon integration of 1-bit samples of signal voltage amplitude corresponding to sine or cosine phases of a controlled center frequency clock used to time the samples taken, but preferably corresponding to both sine and cosine phases of the center frequency clock which is changed after each integration interval to sweep the frequency range of interest in steps. Integration of samples during each interval is carried out over a number of cycles of the center frequency clock spanning a number of cycles of an input signal to be analyzed. The invention may be used to detect the frequency of at least two signals simultaneously.

Abstract: A remote maintenance monitoring system retrofits to a given hardware device with a sensor implant which gathers and captures failure data from the hardware device, without interfering with its operation. Failure data is continuously obtained from predetermined critical points within the hardware device, and is analyzed with a diagnostic expert system, which isolates failure origin to a particular component within the hardware device. For example, monitoring of a computer-based device may include monitoring of parity error data therefrom, as well as monitoring power supply fluctuations therein, so that parity error and power supply anomaly data may be used to trace the failure origin to a particular plane or power supply within the computer-based device. A plurality of sensor implants may be rerofit to corresponding plural devices comprising a distributed large-scale system. Transparent interface of the sensors to the devices precludes operative interference with the distributed network.

Abstract: A Joule-Thomson cryogenic refrigeration system capable of achieving high temperature stabilities in the presence of varying temperature, atmospheric pressure, and heat load is provided. The Joule-Thomson cryogenic refrigeration system includes a demand-flow Joule-Thomson expansion valve disposed in a cryostat of the refrigeration system. The expansion valve has an adjustable orifice that controls the flow of compressed gas therethrough and induces cooling and partial liquefaction of the gas. A recuperative heat exchanger is disposed in the cryostat and coupled to the expansion valve. A thermostatically self-regulating mechanism is disposed in the cryostat and coupled to the J-T expansion valve. The thermostatically self-regulating mechanism automatically adjusts the cross-sectional area of the adjustable valve orifice in response to environmental temperature changes and changes in power dissipated at a cold head.

Abstract: A low friction, object guidance, and gripping finger device for a robotic end effector on a robotic arm, having a pair of robotic fingers each having a finger shaft slideably located on a gripper housing attached to the end effector, each of the robotic fingers having a roller housing attached to the finger shaft. The roller housing has a ball-bearing mounted centering roller located at the center, and a pair of ball bearing mounted clamping rollers located on either side of the centering roller. The object has a recess to engage the centering roller and a number of seating ramps for engaging the clamping rollers. The centering roller acts to position and hold the object symmetrically about the centering roller with respect to the X axis and the clamping rollers act to position and hold the object with respect to the Y and Z axis.

Abstract: A method for determining Richardson Number, Ri, or its reciprocal, RRi, for clear air turbulence prediction using measured potential temperature profiles and determining the vertical gradient of potential temperature, d.theta./dz. Wind vector from the aircraft's instrumentation versus potential temperature dw/d.theta. is determined and multiplied by d.theta./dz to obtain dW/dz. Richardson Number or its reciprocal is then determined from the relationship ##EQU1## for use in detecting a trend toward a threshold value for the prupose of predicing clear air turbulence. Other equations for this basic relationship are disclosed together with the description of a method for combining of other atmospheric observables using multiple regression techniques to produce improved warnings of clear air turbulence.

Abstract: A composite nut is shown which permits a fastener to be inserted or removed from either side with an indicator of fastener engagement. The nut has a plurality of segments, preferably at least three segments, which are internally threaded, spring-loaded apart by an internal spring, and has detents on opposite sides which force the nut segments into operative engagement with a threaded member when pushed in and release the segments for quick insertion or removal of the nut when moved out. When the nut is installed, end pressure on one of the detents presses the nut segments into operative engagement with a threaded member where continued rotation locks the structure together with the detents depressed to indicate positive locking engagement of the nut. On removal, counterclockwise rotation of the nut relieves the endwise pressure on the detents permitting internal springs to force the detents outward and allowing the nut segments to move outward and separate to permit quick removal of the fastener.

Abstract: A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15% by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

Abstract: A phase shifter having a reference path and a delay path, light sources, and superconductive switches. Each of the superconductive switches is terminated in a virtual short circuit, which may be a radial stub. Switching between the reference path and delayed path is accomplished by illuminating the superconductive switches connected to the desired path, while not illuminating the superconductive switches connected to the other path.

Abstract: A sensor assembly to be carried on an aircraft or spacecraft which will travel along an arbitrary flight path, for providing an image of terrain over which the craft travels. The assembly includes a main linear sensor array and a plurality of auxiliary sensor arrays oriented parallel to, and at respectively different distances from, the main array. By comparing the image signals produced by the main sensor array with those produced by each auxiliary array, information relating to variations in velocity of the craft carrying the assembly can be obtained. The signals from each auxiliary array will provide information relating to a respectively different frequency range.

Abstract: A superconducting bearing for a rotating member having a magnet at each extremity of the rotating member; having a bearing made of a material exhibiting Type II superconducting properties, the bearing is formed as a recess in the superconducting material in the form of a cylindrical, closed-end orifice. The bearing exerts levitation forces on the magnets at each extremity of the rotating member. Several methods for controlling the levitation forces exerted by the bearing on the magnets at each extremity of the rotating member are shown. One method is to construct the bearing from two different types of superconducting materials. Another method is to provide heating elements in the bearing. A further method is to provide an electromagnetic coil above the bearing. The bearing could also be segmented or have material removed to control the levitation forces.

Abstract: A method and apparatus are disclosed for edge phasing an array of segments in a segmented primary telescope mirror using white light from a far field source and starting with the inner edge of each segment in the first ring of segments. The segments are individually phased for zero piston and tilt error with respect to the edge of a reference surface in the open center position of the telescope mirror, and proceeding from ring to ring by edge phasing one edge of each segment in each subsequent ring with an edge of a segment in a preceding ring that has been edge phased. After edge phasing of all segments in the telesope mirror array has been completed, full surface phasing can be achieved using a conventional Shack-Hartmann technique followed by finding the RMS best fit for each segment of the mirror array.

Abstract: A disk memory device is provided that will maximize the storage capacity of a memory disk while at the same time maximize the record and playback data rate. Two recording disks are mounted upon a common shaft that is rotated at a fixed speed. Each disk has a recording area including a surface upon which data can be recorded/read in the form of tracks arranged either in concentric tracks or in a spiral. The recording area surfaces are divided into multiple concentric track groups. Two read/write heads and two head positioning servos (including electronic controls) are mounted such that each disk recording surface can be read out or written by the read/write heads. Each track of the multiple track groups of the first disk are given designated numbers beginning with the outer track of the outermost or edge track group and continuing in higher consecutive numbers until the inner track of the innermost track group is designated.

Abstract: The conductivity is increased an order of magnitude and interfacial charge transfer resistance is substantially decreased by incorporating a minor amount of 12-Crown-4 ether in a polyethylene oxide-lithium salt solid electrolyte film.

Abstract: A method of reducing electrophoretic mobility of macromolecules, particles, cells and other substances is provided which comprises interacting in a conventional electrophoretic separating procedure the substances with a polymer-linked affinity compound comprised of a hydrophilic neutral polymer such as polyethylene glycol bound to a second component such as a hydrophobic compound, an immunocompound such as an antibody or antibody active fragment, or a ligand such as a hormone, drug, antigen or a hapten. The reduction of electrophoretic mobility achieved is directly proportional to the concentration of the polymer-linked affinity compound employed, and such reduction can comprise up to 100% for particular particles and cells. The present invention is advantageous in that electrophoretic separation can now be achieved for substances whose native surface charge structure had prevented them from being separated by normal electrophoretic means.

Abstract: A coupling device with a thermal interface occuring along a curved vertical surface is disclosed. One curved surface is on a cold pin extending from a "cold" object and the other curved surface is on a hot pin extending from a "hot" object. The cold pin is fixed and does not move while the hot pin is a flexible member and its movement towards the cold pin will bring the two curved surfaces together forming the coupling and the thermal interface. The actuator member is a shape-memory actuation wire which is attached between the hot pin and the hot object. By properly programming the actuation wire, heat from the hot object will cause the actuation wire to move the hot pin towards the cold pin forming an effective thermal interface. The shape-memory actuation wire is made from a shape-memory-effect alloy such as Nitinol.

Abstract: An autonomous docking system is provided which produces commands for the steering and propulsion system of a chase vehicle used in the docking of that chase vehicle with a target vehicle. The docking system comprises a passive optical target affixed to the target vehicle and comprising three reflective areas including a central area mounted on a short post, and tracking sensor and process controller apparatus carried by the chase vehicle.

Abstract: A computer-simulated cortical network computes the visibility of shifts in the direction of movement and computes: 1) the magnitude of the position difference between the test and background patterns, 2) localized contrast differences at different spatial scales analyzed by computing temporal gradients of the difference and sum of the outputs of paired even- and odd-symmetric bandpass filters convolved with the input pattern and 3) using global processes that pool the output from paired even- and odd-symmetric simple and complex cells across the spatial extent of the background frame of reference to determine the direction a test pattern moved relative to a textured background. The direction of movement of an object in the field of view of a robotic vision system is detected in accordance with non-linear Gabor function algorithms. The movement of objects relative to their background is used to infer the 3-dimensional structure and motion of object surfaces.

Abstract: An angular position encoder is provided that minimizes the effects of eccentricity and other misalignments between the disk and the read stations by employing heads which incorporate beam steering optics with the ability to actively track the disk in directions along the disk radius and normal to its surface. The device adapts features prevalent in optical disk technology toward the application of angular position sensing. A reflective disk and the principles of interferometry are employed. The servo controlled steering optics move so as to acquire a track on the disk lying at a predetermined radius and distance below the head, and then adjust position and orientation in order to maintain view of the disk track as required. Thus, the device is actively self-aligning.

Abstract: A high resolution x-ray microscope for imaging microscopic structures within biological specimens has an optical system including a highly polished primary and secondary mirror coated with identical multilayer coatings, the mirrors acting at normal incidence. The coatings have a high reflectivity in the narrow wave bandpass between 23.3 and 43.7 angstroms and have low reflectivity outside of this range. The primary mirror has a spherical concave surface and the secondary mirror has a spherical convex surface. The radii of the mirrors are concentric about a common center of curvature on the optical axis of the microscope extending from the object focal plane to the image focal plane. The primary mirror has an annular configuration with a central aperture and the secondary mirror is positioned between the primary mirror and the center of curvature for reflecting radiation through the apertture to a detector.

Abstract: A roller locking brake structure includes a roller locking/lifting ring, a housing, a set of conical locking rollers, a striker ring and a drive disc. The roller locking/lifting ring includes respective V-shaped locking cam surface segments for each locking roller which is in the form of a truncated cone and provides a force and torque reaction surface for forces and torques generated in the braking process as well as providing a channel for a magnetic coil and flux return path of a magnetic circuit used to release a conical roller when the brake is off. The locking conical rollers couple the ring to the rim surface of the drive disc which provides another cam surface. The striker ring is located adjacent the rollers and is pulled down against the small end of the rollers by an electromagnetic coil when energized to decouple the locking rollers from the drive disc and thus cease the braking action.