Abstract: A knob securing mechanism secures a knob to a shaft. A uniquely shaped retaining clip attaches in a channel of the knob. The channel intersects a bore in the knob which receives the shaft. The shaft has a groove corresponding to the retaining clip such that the retaining clip and the groove couple when the knob is fully seated in the bore of the shaft. The retaining clip operates as a spring to resist axial motion between the knob and shaft. Ramps are formed on the shaft to facilitates both installing and removing the knob from the shaft by application of axial force. Locking lugs on the shaft engage corresponding locking lugs in the knob to secure the knob rotationally to the shaft. The invention is particularly useful for attaching translucent knobs to shafts of an avionics control panel.

Abstract: The present invention is an optical transmission system comprising an optical source, a first lens and a second lens, a multimode optical waveguide, and a phase-only filter. The optical source generates an optical signal having a predetermined wavelength which is received by the first lens. The signal is then sent from the first lens through the phase-only filter and then to the second lens. The second lens then focuses the signal into the multimode optical waveguide. The multimode optical waveguide has predetermined dimensions and has multiple modes. The phase-only filter excites a plurality of modes in the optical waveguide to approximate equilibrium modal power distribution as the optical signal is received into the optical waveguide.

Abstract: A feedback system for use in controlling control moment gyroscopes that are used in positioning a spacecraft where the relative rate of rotation is determined from the difference between the rotation rate of the gimbals of the CMGs and the rotation rate of the frame about the gimbal axis. The inertial reference units on the spacecraft are utilized as the source of measured rates of rotation of the three spacecraft axes with respect to a predetermined axis and these are converted to the rates of rotation of the frame about the individual CMG gimbal axes.

Abstract: A container with an inside surface and a mass mounted for oscillation in the container with a pair of bellows in the container each having a bias spring therein and a removable end to expose the interior of the bellows to exchange the spring for easy tuning of the damping characteristics and a plurality of balls, one each positioned in a plurality of troughs around the periphery of the mass proximate the ends there to bear against the inside surface so as to provide low friction oscillation of the mass in the container.

Abstract: A memory interface system is operable with a ARINC 629 terminal controller for directing storage of data message received by the terminal controller into a memory device, and associating with each of the words stored in the memory device a tag word which identifies the word type being stored.

Abstract: A differential global position system wherein a DGPS ground station encodes signals from a plurality of satellites and transmits the encoded signal with satellite-specific pseudo range error signals and a ground station repeaters located remote from the DGPS ground station to receive the encoded signal and retransmit it to an airborne object.

Abstract: A method and apparatus using a simplified language consistent with air traffic control syntax for inputting, displaying and controlling the operation of a flight management system of an aircraft to comply with the instructions received by the pilot from the air traffic controller.

Abstract: Communications systems architecture using a single shared resource bus to interconnect a plurality of subsystems each handling information having a first predetermined importance level and an error detect wrapper for encoding information to and from each such subsystem to detect errors in transmission along the shared resource bus. A heartbeat monitor is also provided for use in those subsystems handling information having a second predetermined level of importance to disable the subsystem if an error occurs within the subsystem.

Abstract: A system to alter the voltage supplied to the linear regulator of a pulsed transmitter in accordance with the temperature of the regulator, the minimum voltage required for a transmission and the specific aircraft installation requirements so as to reduce problems of heat dissipation in the regulator.

Abstract: A tuned mass damper incorporating a container with an inside surface, two end portions and a mass mounted for oscillation between the end portions by a pair of bias springs, the two end portions being filled with a compressible gas to reduce the effects of temperature variations on the damping characteristics, to increase the damping with increased amplitude of oscillation of the mass and to minimize size and weight of the damper, the mass being supported for oscillation by using a plurality of grooves at each end of the mass with a single ball in each groove to provide frictionless and self centering motion of the mass.

Abstract: A damping mounting structure for use between two members for isolating motion changes which incorporates a plurality of dampers connected between the two members with spring members operating in parallel with the dampers to provide stiffness and where the springs are pneumatic to provide proper stiffness when the load is heavy without damage to the springs and/or to provide variable stiffness when desired.

Abstract: A radar system embeds information into the radar picture data for display on any display device. The radar receiver communicates weather data to a signal processor which generates a weather array. An I/O processor transmits data in the weather array to a display device via a picture bus. Alphanumeric data which is to be embedded into or combined with the weather array is stored in a message array. Font information for each alphanumeric character is stored in a font array. The message array and the font array are combined and translated into a text array which corresponds to the weather array. Prior to transmitting each radial of data to the display device, the I/O processor copies the appropriate radial data from the text array to the weather array thereby causing the desired alphanumeric characters to be displayed on the display device.

Abstract: Apparatus and method for controlling a plurality of pulse width modulated devices from a single controller including condition sensors to input the controller, a logic unit to determine the error between the sensed values and the desired values of the conditions and a direct memory access unit which is digitally coded with the error values, the pulse width modulated device being connected to receive the outputs of the direct memory access unit and operable to control the conditions.

Abstract: A system used with a system having a carrier delay to determine the phase of a signal before the delay and to recover the signal after the delay. Two signals at different frequencies are sent through the system having a carrier delay. One signal will be the signal that contains the phase information. The other signal is a reference signal to generate a reference for the first signal.

Abstract: A tuned mass damper using a single predetermined mass connected to springs of predetermined stiffness along each of at least two directions to absorb energy from a vibrating structure to which it is attached and damp the vibrations in a rapid and efficient manner with a minimum of weight and volume used.

Abstract: A navigation system, incorporating a unique method for detecting failures and determining an accuracy or error bound, has a receiver for receiving signals from several remote transmitters and a processor for determining a position solution from the signals. The processor, preferably employing Kalman filtering techniques, also determines several position subsolutions from subsets of the signals. The processor then computes covariance-based solution separation parameters based on statistical worst-case differences, or separations, between the position solution and the subsolutions. Similarly, the processor also computes error parameters defining statistical worst-case errors in each position subsolution. With the solution separation and the subsolution error parameters, the processor determines an error bound for the position solution. The processor also uses the separation parameters as detection thresholds for detecting transmitter failures.

Abstract: A subtractive color liquid crystal display employing circular polarizers. In the subtractive color display each picture element has three liquid crystal switching elements. Adjacent to each liquid crystal switching element are a circular polarizer and 1/4 wave retarder plate combination. The circular polarizer and 1/4 wave retarder plate combination create a linear notch polarizer for an isolated and steep polarization band for each of the primary colors (red, green blue). The notch polarizes are tuned to the particular backlight of the display in order to provide increased light transmittance and color gamut.

Abstract: A fault tolerant inertial reference system employs two independent inertial reference units each having its own inertial sensor array with redundant output information. Each inertial reference unit includes an independent source of position and velocity information through employment of a satellite positioning system. In turn, a high-speed error estimator processes inertial sensor output data from a local inertial sensor array with inertial sensor output data from another external inertial sensor array for determining high-level errors, and a low-speed error estimator processes output data from the local inertial sensor array with the velocity and position information separately obtained from the satellite positioning system for determining low-level errors. In turn these high and low-level errors are processed to determine a fault-free inertial sensor configuration for subsequently determining reliable fault tolerant inertial reference data obtainable with a minimum set of inertial sensors.

Abstract: The pH of a material containing lignin is determined by directing an ultraviolet light at the material. One of the characteristics of lignin is giving off a fluorescence in response to an ultraviolet light. A monochrometer is used to observe the fluorescence and produces a signal of the intensity of the fluorescent light at varying wavelengths. This signal is displayed on a display means such as a computer screen. Calibration occurs before the pH measurement of the material occurs. The calibration data along with information from the signal is used to calculate the pH of the material. No contact with the material is required in determining the pH of the material.

Abstract: A low-cost portable handheld still-frame thermal camera for capture of calibrated digital thermographic infrared images having a lens assembly, a slideable linear array of uncooled 8-12 um thermal IR sensors, a slider actuation mechanism, and associated digital processing capability for calibrating, displaying, and storing images captured by the camera. The sensors are preferably thermoelectric sensors. The lens passes infrared radiation, the array is contained in an evacuated chamber, and operates at room temperature. The thermographic images may be displayed immediately or remotely or may be printed by conventional techniques.