Abstract: A digital to analog resolver converter uses a digital to analog converter to convert a part of the digital input to a corresponding analog angle value. This analog angle value is applied to sine and cosine function generators which use the equations of chords to approximate the value of the sine and cosine functions in one octant. Bits of the digital input are used to select slope values from the chord equations for approximating the sine and cosine of the analog angle value. The digital to analog resolver converter uses the minimum number of precision resistors to generate the sine and cosine slope and intercept values for the equations of a given number of approximating chords.

Abstract: A doppler radar/inertial system is provided for producing navigational and fire control information for an aircraft, and which includes means for developing vertical reference signals accurately at one location and for then transferring the signals to a second location without incurring errors due to aircraft flexure. The system includes high quality accelerometers and gyroscopes mounted at one location in the aircraft for developing accurate vertical reference signals; and a high quality accelerometer and low cost gyroscope at a second location where accurate vertical reference information is required. The system includes circuitry for comparing the output of the high quality accelerometer at the second location with the accelerometer outputs at the first location, the difference of which is a function of the error in the vertical reference at the second location, as indicated by the low cost gyroscope.

Abstract: A high accuracy digital to analog resolver converter uses a read only memory device (PROM) programmed to generate a digital signal proportional to the inherent systematic error of a digital to analog resolver converter. This signal is then converted to analog form by conventional means and combined with the primary signal in analog form thereby substantially increasing the accuracy of a digital to analog resolver converter.

Abstract: An electrostatic pickoff well suited for use in a two-axis electrostatically-captured rotor rate gyroscope is shown. Displacement currents, which flow between stator electrodes and the V-shaped annular electrically conductive rotor capturing the rotor, are processed so as to produce signals related to rotor position but independent of capture currents. When closed through a 5 degree-of-freedom positional servomechanism, rotor position signals are effective in producing rotor capture with net zero rotor current without producing rotor distorting forces.

Abstract: A force rebalanced accelerometer utilizing a spherical proof mass disposed in a fluid and in which fluid pressure pulses developed by positive displacement pump are used to balance inertial forces.

Abstract: The proof mass of a pendulous accelerometer is floated in a liquid metal such as mercury which has high surface tension and non-wetting characteristics within a specially designed cavity such that neutral bouyancy conditions are achieved for all principle axes except the input axis.

Abstract: A densely packed low weight, low volume, minimum temperature gradient memory array comprising a bilateral printed circuit board having a plurality of ferrite cores arranged in columns and rows mounted on one side and a plurality of integrated circuit diode flatpacks mounted on the other side. A ground plane comprising a thin metallic layer isolates the core plane from the mounting and also serves as a means for maintaining a minimum temperature gradient across the core plane. A heat conductor removes unwanted heat from the array, and the connections to elements of the array are grouped to reduce wiring runs.

Abstract: A novel approach for generating four symmetrically located beams from a printed antenna using a corporate feed system is described. One approach used to generate four low side lobe beams utilizes a planar aperture. The second approach generates four low side lobe beams from a cylindrically shaped aperture. The generation is accomplished without the use of active phase shifting devices. The output phase function of the feed can be reversed which causes the beam to be pointed equally in the opposite direction. The radiating elements are designed to be symmetrical about the center of the aperture in a direction orthogonal to the radiating elements. By placing identical feeds at both ends, four beams can be obtained, each pointed in a direction symmetrically located about the normal to the antenna. Such an approach is applicable to both planar arrays and cylindrically shaped arrays.

Abstract: A solid state optical scanner comprising a frequency generator that vibrates a sonic transducer which in turn sets up traveling waves in an acousto-optic medium. These waves form regions of compression and rarefaction in the medium causing the medium to act as a Bragg angle grating to an incident light source. Optical lenses and a photo detector are positioned behind the medium. Consequently, the light leaving the medium is diffracted into a single order and focused onto an image plane. A photodetector is placed at the image plane and the signal obtained is processed to develop information to determine the direction from the scanner to the incident light source.

Abstract: A cylindrically shaped leaky wave antenna utilizing a cylindrically shaped printed grid antenna fed by a curved wave guide feed array utilizing anti-phase edge cut slots cut in accordance with a phase synthesis technique to provide a desired squinted beam resulting in a low cost conformal antenna without the use of active phase elements.

Abstract: A signal conditioning circuit for a fixed rise time, variable amplitude receiving system (TACAN) that digitizes the time of arrival and samples the pulse amplitude at the receiver's last intermediate frequency (IF) stage before video detection. The time of arrival measurement is performed by counting a fixed number of successive threshold crossings of the IF carrier, utilizing a pair of comparators having two inputs each. One input of each comparator is coupled to the IF stage. The other input of each comparator is coupled to a point of reference potential, one comparator being referenced to ground and the other being coupled to a small positive threshold voltage level. The output of the grounded comparator is delayed, and the delayed output is used as a clock signal to the remaining circuitry. The output of the threshold comparator provides data pulses, one data pulse being generated each time that the IF signal goes above the threshold value.

Abstract: A precision accelerometer is provided which is capable of measuring linear accelerations along three axes. The accelerometer incorporates a self-charging radioactive particle as the inertial acceleration sensing mass. The particle is contained in an evacuated cubical chamber, and the position of the particle within the chamber is established by the differential between the mean number of emitted charged particles detected at the opposite walls of the chamber, whenever the particle moves from a central position within the chamber. The accelerometer includes an electronic control system which generates feedback signals that tend to maintain the particle centered within the chamber in the presence of accelerations, and at the same time to provide electrical outputs which are measurements of the accelerations along the three coordinate axes.

Abstract: A caging mechanism for a gyro in which a flat split ring lying in a plane perpendicular to the gyro rotor spin axis is deformable so that its inside diameter is enabled to capture the gyro rotor. A gas activated piston separates tabs formed on the split ring causing it to cage or uncage the rotor.

Abstract: Stable reference gyroscopic apparatus is provided in the form of an angular displacement sensor which employs an end-supported vibratory rod or wire, instead of the commonly used rotatable element. The apparatus of the invention incorporates an improved means for maintaining the vibrational amplitude of the center of the vibratory element constant, and electronic circuit means for causing the orbit of center of the vibratory element to remain in a straight line, both means being effective to eliminate the major sources of potential drift in the sensor.

Abstract: A computing system for performing digital sequential coordinate transformations on n dimensional vector input data referenced to a sensor system and ultimate outputting of the n dimensional vector data having basis in an alternate reference system in a form compatible with utilization equipment. The system adopts the basic "Cordic Algorithm" but eliminates the need for interim storage elements by the provision in a digital computing resolver of n registers, one for each of the n orthogonal axes plus a register for the rotation angle wherein the orthogonal registers are selected sequentially by the program in pairs to develop the terminal vector solutions. Additionally, the system provides a means of cross-addition between registers which reduces register capacity and eliminates the need for circuitry to perform trigonometric subroutines.

Abstract: Velocity sensing apparatus which permits measuring the velocity magnitude and sense of direction using the single radiating antenna illuminating a spot on the ground from which power is back-scattered to three receiving antennas. The receiving antenna outputs are grouped into pairs and processing of the signals done to obtain direct sum and quadrature sum waveforms with the point of crossing of the spectrum of the direct sum and quadrature sum waveform indicating the magnitude of velocity and the sign of the slope of the spectrum of the quadrature sum waveform determining the direction of the velocity.

Abstract: A rate sensor comprising a glass annulus filled with an electrolytic fluid. A plurality of electrodes in contact with the electrolyte have an electrical field established between them which in turn starts a flow of ions between the electrodes. When the device is rotated about a predetermined axis the flow of ions between certain electrodes is increased. Electronic means connected to output electrodes senses the change in ion flow and determines the rotational rate of the vehicle upon which the sensor is mounted.

Abstract: An improved adjustable integrated circuit carrier made in multiple pieces comprising a master base and two identical element sections which can be attached to a master base in a position determined by the dimensions of a component to be protected thereby permitting a single set of manufacturing tools to produce pieces which can be assembled to accomodate any of a wide variety of different sized components.

Abstract: An electrostatic motor which is well suited for an electrostatic gyro rotor spin up, spin down system which provides positive starting at any rotor position, choice of clock-wise or counter-clockwise rotation, spin up and spin down modes with automatic coast and stop modes, choice of full speed along with having zero induced rotor voltage and non-displacemental force generation is shown.

Abstract: A digital tacan system which provides improved bearing and range accuracy and allows faster acquisition. In computing, both bearing and range updates are maintained current using a Kalman filter. Portions of the computation may be performed in an on-board computer with the remainder done is a special purpose computer capable of being implemented using a few custom made MOS/LSI chips.