Abstract: A signal processor which involves separation of the cell signals from a magnetic resonance gyro (MRG) using phase locked loops that also serve as frequency multipliers, phase shifting one cell output to maintain phase comparisons within the monotonic region of the phase detectors, PDM/Digital conversion of the MRG signals and finally microcomputer processing to obtain gyro angle to the required resolution and update rate.

Abstract: An equilateral triangular ring laser gyroscope contains drivers to vibrate two of the mirrors synchronously and oppositely along paths displaced by about 4.27.degree. from the bisector of the vertex angles at which those mirrors are located. The magnitude of displacement is about 0.761 .lambda., where .lambda. is the wavelength of laser radiation. The purpose of the vibration is to reduce the lock-in effect in the ring laser gyroscope.

Abstract: A ring laser gyroscope has at least two of its mirrors vibrated perpendicular to their reflective surfaces by equal and opposite amounts to maintain the total beam path length constant. The amplitude of vibration causes the beams to be shifted across surfaces of all of the mirrors by a distance that is at least close to a Bessel zero distance so as to reduce the intensity of back scattered radiation at the main wavelength to a value close to zero. For an equilateral triangular ring laser gyroscope, two of the mirrors are vibrated between about 0.66.lambda. and 0.74.lambda., optimally about 0.71.lambda.. For an isosceles triangle having vibrating mirrors at two vertexes having angles of about 51.65.degree., the magnitude of vibration should be about 0.91.lambda..

Abstract: A commutator brush holder mounts a pair of tension band springs in quadrature relation. Both springs contact the brush end remote from the commutator and urge the brush into contact with the commutator, with constant force. The quadrature springs promote full and intimate contact between the brush and commutator, thereby minimizing brush bounce and tilt and resultant transient signal generation.

Abstract: An improved ladder network for use in a converter utilizing a single ladder network with single pole double throw switches to simultaneously implement nonlinear sine and cosine functions.

Abstract: An absolute digital clock system which is capable of counting absolute time despite the disruptive effects of a nuclear event, or other disturbance, on the electronic circuitry of the system. The clock system of the invention includes a master quartz crystal oscillator stage, and a string of counter stages connected thereto each including a binary counter for counting down from the frequency of the preceding stage to a lower frequency, and each including a crystal oscillator phase-locked with the binary counter and producing a signal at the lower frequency.

Abstract: An optical device for the simultaneous transmission and reception of optical data on the same optical waveguide. A transmission and receiving means at each end of the fiber optic cable permits simultaneous transmission. Each transmit/receive means comprises a pedestal supporting an emitter and photodetector. The emitter is mounted centrally of the inner surface of the pedestal at the focal point of a circular ellipsoidal reflector. The photodetector is also mounted centrally of the inner surface of the pedestal and placed forward of the emitter. In this manner the emitters and photodetectors at each end of the fiber optic cable can transmit and receive simultaneously or in sequence on the same optical waveguide.

Abstract: In order to eliminate the day-to-day gyro drift phenomena which result from interaction of the magnetic pole position of the synchronous motor typically used to drive the gyro and the gyro wheel, an induction motor controlled by a phase locked loop referenced to an appropriate control frequency is utilized to drive the gyro.

Abstract: A surveying instrument sensor which includes a gimbal supported for rotation within a casing, a torquer coupled to rotate the gimbal with a first two-axis flexure suspended gyro supported on the gimbal with its spin axis perpendicular to the axis of the gimbal and one of its sensitive axes aligned with the axis of the gimbal, a second two-axis flexure suspended gyro disposed on the gimbal with its spin axis alinged with the axis of the gimbal and having two sensitive axes outputs orthogonal thereto. The output of the first gyro is coupled to the torquer to form a gimbal stabilized loop and the outputs and torquing inputs of the second gimbal coupled into rate capture loops with output signals obtained from the rate captured loops permitting fast and accurate surveying of a well pipe.

Abstract: A device for converting ternary-coded electrical pulse trains into binary-coded pulse trains, by interrupting a binary zero-rate data stream, representing one ternary condition, to supply an output voltage or no output voltage, representing the other ternary conditions.

Abstract: An antifriction bearing having a ball bearing retainer positioned between an outer race and an inner race. A plurality of slidable wedges of the bearing conforming to the dimensions of the raceways are mounted in slots in the periphery of the retainer. In operation a centrifugal force is exerted on the retainer urging the wedges of the retainer to ride in the raceways. The wedges thus act as wipers maintaining a smooth oil film for the ball bearings regardless of the amount of lubricant in the raceways.

Abstract: A circuit for converting serial binary coded ternary information received on one line into ternary signals for transmission on two lines. The presence or absence of a pulse in a first interval is compared with the presence or absence of a pulse in the succeeding interval and a voltage representing one ternary condition is transmitted on one line if pulses are present, on another line, if pulses are absent, and no signal is transmitted if alternating pulses are received.

Abstract: A piezo-electric crystal vibrating in several modes controls several frequencies generated by voltage controlled oscillators simultaneously. The output of each voltage controlled oscillator is fed to a summing amplifier which drives the crystal. The output of the crystal is fed to individual phase detectors; each phase detector is also supplied with the output of a voltage controlled oscillator and generates a voltage proportional to the phase difference between the voltage controlled oscillator and the crystal output for correcting the output frequency of each oscillator.

Abstract: A vibrating beam accelerometer is provided which includes a quartz vibrating beam resonator as aa force transducer, and which also includes resiliently biased relief arms which release the quartz beam should the acceleration forces become excessive. The relief arms serve to protect the beam against overload forces, and to permit the proof mass of the accelerometer to be sufficiently high as to enable the accelerometer to measure accelerations in a relatively wide range as compared with the range capabilities of prior art vibrating beam accelerometers.

Abstract: A kinematic inertial sensor is provided for measuring angular velocity and position relative to inertial space about one or more measurement axes. The kinematic inertial sensor includes an angular rate sensor having a ring of conducting fluid contained in a housing, a set of gimbals for supporting the angular rate sensor, signal generating means, torque applying means, angle measuring means, resolver means, component processing means, and signal applying means.

Abstract: A method of manufacturing a flexure suspension assembly which includes forming four quadrantally and radially disposed single axis flexure joints in a first cylindrical member and four quadrantally and radially disposed single axis flexure joints in a second cylindrical member. The longitudinal axes of the flexure joints in the first cylindrical member are substantially parallel to the longitudinal cylinder axis which is coincident with the spin axis of the suspension assembly and the longitudinal axes of the joints in the second cylindrical member are substantially perpendicular to the longitudinal axis of the second member. The first and second members are integrally joined together in concentric relationship with the bending axes of the four joints in each cylinder in radial alignment to form a composite cylindrical member. The composite cylindrical member is then separated by electro discharge machining into the foregoing components of the flexure suspension assembly.

Abstract: A machine for manufacturing high strength flexure hinges having use in accelerometers. A source of metal material is splat-cooled after it has been heated to a molten state. An induction heater heats the metal material to the molten state and the molten metal is rapidly cooled while being pressed between two water cooled wheels. The wheels are provided with indentations and protuberances on their surfaces to produce flexure hinges and strengthening beams. A chute is provided to catch the flexures as they leave the wheels preventing damage to them.

Abstract: A synchro buffer amplifier is provided which uses two matched amplifiers respectively connected to the primary windings of two transformers. Two input leads are respectively connected to the inputs of the two amplifiers and a third input lead is grounded. The secondary windings of the two transformers are connected in series, and three output leads are respectively connected to the other sides of the two secondary windings and to the common secondary connection. Direct feedback is provided for each amplifier. Any circuit unbalance is compensated by the insertion of a low value choke in the common transformer secondary connection. Three capacitors are connected across the respective output leads partially to tune the loads, and thereby to nullify to some extent the effects of heavy inductive loads so as to allow operation of the buffer amplifier over a wider range of loads than would otherwise be possible.

Abstract: An electrical circuit interposed between the pickoffs and torquers of a two-axis gyroscope. The circuit output controls the torquers. When the pickoff signals vary at the nutation frequency, the angular accelerations produced by the torquers damp the nutation. No angular accelerations are produced when the pickoff signals are not varying and only negligible angular accelerations are produced when the pickoff signals vary at a frequency other than the nutation frequency.

Abstract: The invention is concerned with angular rate sensors, and particularly with ring laser gyroscopes which includes means for compensating for the effects of temperature gradients and residual lock-in. A ring laser gyroscope is provided which has a triangular block configuration, and which incorporates a triangular-shaped laser resonant cavity defined by three corner mirrors, including an output mirror. The ring laser gyroscope of the invention includes an optical wedge and a prism attached to its output mirror which permit the center of support of the gyroscope to be located in the plane of symmetry of the block. The gyroscope is mechanically vibrated about its center of gravity to prevent lock-in effects at low angular input rates. The construction of the gyroscope reduces temperature gradients across the plane of symmetry of the instrument, which temperature gradients produce spurious output signals in the absence of an input angular rate.