Abstract: In one example, a vehicle includes a platform and a yaw sensor mounted on the platform. The yaw sensor provides an indication of a yaw rate of rotation of the yaw sensor. The vehicle also includes an actuator that rotates the platform. The vehicle also includes a controller coupled to the yaw sensor and the actuator. The controller receives the indication of the yaw rate from the yaw sensor. The controller also causes the actuator to rotate the platform (i) along a direction of rotation opposite to a direction of the rotation of the yaw sensor and (ii) at a rate of rotation based on the yaw rate of the yaw sensor. The controller also estimates a direction of motion of the vehicle in an environment of the vehicle based on at least the rate of rotation of the platform.

Abstract: The invention relates to a compass or direction determination device comprising one or more rotation sensitive sensors and means for rotating the one or more rotation sensitive sensors, wherein the means for rotating is configured to produce two or more rotation speeds of the one or more rotation sensitive sensors during a single direction determination operation.

Abstract: The magnitude of a sensed, raw magnetic field in a portable device is monitored over a given time interval. The monitored magnitude is compared with predetermined criteria. Based on the comparison, recalibration of a compass function is signed. Other embodiments are also described and claimed.

Abstract: The magnitude of a sensed, raw magnetic field in a portable device is monitored over a given time interval. The monitored magnitude is compared with predetermined criteria. Based on the comparison, recalibration of a compass function is signed. Other embodiments are also described and claimed.

Abstract: Calibration systems and methods simultaneously calibrate a magnetic compass and gyroscopes. An exemplary embodiment rotates the field calibration system. Based upon the rotation sensed by the magnetic compass and the gyroscopes, the field calibration system determines compensation for both the magnetic compass and the gyroscopes.

Abstract: An apparatus and method for compensation of the effects of various bias errors encountered by inertial rate gyroscopes, particularly vibrating element gyroscopes, configured to detect heading relative to true north. Certain embodiments are suitable for reducing rotational dynamic errors associated with rotating gyroscopes. Other embodiments may include compensation of biases not related to rotational dynamics, such as thermal drift. The various methods disclosed may also account for the bias by sampling the rotational vector of the earth at an arbitrary heading, and at a heading that is 180° offset from the arbitrary heading. The sequence may be repeated numerous times to compensate for bias drift. The bias drift may be constant with respect to time (linear) or changing over time (non-linear) during the data acquisition sequence. Some embodiments include methods that utilize data from accelerometers to infer the bank and elevation angles as well as earth latitude location relative to the equator.

Abstract: An apparatus and method for compensation of the effects of various bias errors encountered by inertial rate gyroscopes, particularly vibrating element gyroscopes, configured to detect heading relative to true north. Certain embodiments are suitable for reducing rotational dynamic errors associated with rotating gyroscopes. Other embodiments may include compensation of biases not related to rotational dynamics, such as thermal drift. The various methods disclosed may also account for the bias by sampling the rotational vector of the earth at an arbitrary heading, and at a heading that is 180° offset from the arbitrary heading. The sequence may be repeated numerous times to compensate for bias drift. The bias drift may be constant with respect to time (linear) or changing over time (non-linear) during the data acquisition sequence. Some embodiments include methods that utilize data from accelerometers to infer the bank and elevation angles as well as earth latitude location relative to the equator.

Abstract: An inertial measurement unit is provided. The inertial measurement unit comprises two rotational axes, wherein a first of the two rotational axes is aligned nominally along a thrust axis and a second of the two rotational axes is aligned substantially perpendicular to a plane formed by a local gravity vector and a thrust vector, and one or more sensors which rotate about the second rotational axis.

Abstract: To provide a gyro compass for the use of a high speed ship, in a gyro compass of the type having north-seeking means which is applied to support a gyro sphere or gyro case immersed in a liquid in a tank, a substantially first-order lag filter is provided in an azimuth follow-up loop or a damping loop, the substantially first-order lag filter having a time constant T.sub.F which is approximately equal to a ratio C/k.sub.T of the viscosity torque coefficient C to the twisting torque coefficient k.sub.T of the torque produced between the tank and the gyro case. A speed error correcting means has a substantially first-order lag filter having a time constant which is approximately equal to that of the north-seeking means, and is applied to correct the output of azimuth indicator by a speed error correcting angle through the substantially first-order lag filter.

Abstract: An engineering drawing plotter includes a feed roller for moving paper lengthwise bidirectionally with respect to one or more plotting pens. A counter installed on the plotter includes a pulse switch for measuring absolute lengthwise paper displacement, a direction transducer for determining paper movement direction, and a counter responsive to the measuring device and direction indicating device, for determining and displaying cumulative net paper displacement.

Abstract: An offset-drift correcting device is designed for a gyro-sensor mounted on an object and outputting a signal representing an angular speed of the object. The device includes a first section for detecting whether or not the object is rotating. A second section connected to the gyro-sensor is operative for smoothing the angular speed represented by the output signal of the gyro-sensor, and deriving an average angular speed of the object from the angular speed represented by the output signal of the gyro-sensor. A third section connected to the first section and the second section is operative for estimating an offset level of the output signal of the gyro-sensor in response to the average angular speed derived by the second section in cases where the first section detects that the object is not rotating. The third section includes an adaptive filter processing an output signal of the second section which represents the derived average angular speed.

Abstract: On an aircraft it is proposed that the orientation (pitch and roll attitudes and heading) of a support structure (10), such as the structure supporting the optical head of a head-up control system, be regulated by means of an inertial unit (16). The said unit is firstly placed on its previously regulated rack (14) in the hold of the aircraft and the three orientation parameters are measured. The inertial unit (16) is then placed on an intermediate support (26) fixed to the support structure (10) and the orientation parameters are again measured. Following the comparison of the two measurements, the orientation of the support structure (10) is corrected so as to cancel out their differences.

Abstract: In a ribbon suspended meridian gyroscope in which the gyroscope restoring moment is compensated by a compensating moment, which compensating moment is measured, a North reference angle is determined from a number of different measurements taken in various azimuthal positions. In order to shorten the total measurement time required, for each current individual measurement, the degree of accuracy required for this current individual measurement is determined from the measurement results of the previous measurements in accordance with the magnitude of the effects caused by an error of the individual measurement upon the error in determining the direction of North. The current individual measurement is then carried out to this degree of accuracy. In this manner, each individual measurement is only carried out to the degree of accuracy which corresponds to the weight of this individual measurement in the total error-budget for the North-determination for the respective North reference angle.

Abstract: A gyro compass having a gyro case housing therein a gyro and supported with freedom of three axes, functions for outputting a signal corresponding to an inclined angle of the gyro spin axis relative to the horizontal plane, and a function for applying a torque around a vertical axis of the gyro case in proportion to an input signal. A controller is supplied with a signal corresponding to the inclined angle and a latitude value at which the gyro compass is located, and a constant relative to the input latitude value is determined by the controller after the gyro compass is energized. A signal, resulting from differentiating the signal corresponding to the inclined angle during a predetermined time, is added to the product of the signal corresponding to the inclined angle and the constant. This added signal functions as the input signal for the gyro, whereby a constant optimum north-seeking movement is carried out regardless of the change of the latitude value.

Abstract: A strapped down astro-inertial navigator includes a roll outer gimbal, a pitch inner gimbal and a platform coupled to the inner gimbal. An instrument cluster which includes X-axis, Y-axis and Z-axis ring laser gyros (RLGs) and associated accelerometers is mounted to the platform. Also hard mounted to the platform is a stellar sensor which includes a telescope and a solid state focal plane array which views stellar reference objects. In an astro-inertial mode of operation one or more stellar objects are tracked for a period of time. The roll and the pitch gimbals are employed to point the telescope and, periodically, to observe and average out the effects of star sensor and horizontal accelerometer errors. The star sensor error observability is accomplished by periodically rotating the inner and outer gimbals through 180.degree. and the stellar objects once again tracked. Due to the 180.degree. rotation boresight errors within the stellar tracker are observed and compensated for. The 180.degree.

Abstract: An output signal of a gyroscope is input to two differential circuits having different characteristics in a high frequency band. Output signals of the differential circuits are compared in a comparison circuit, and the output signal of the gyroscope at the time when the output signals of the two differential circuits are equal is output from a sampling hold circuit. In the two differential circuits, the difference of the output signal of the gyroscope and an output signal of the sampling hold circuit is output. The output signal of the gyroscope may be input to a time constant circuit having a switching function and a hold function. At this time, the difference of the output signal of the gyroscope and the output signal of the time constant circuit is output from the differential circuit. The output signal of the differential circuit is compared with a reference voltage generated in a reference voltage circuit in a comparator.

Abstract: A slicing guide marker for marking impressionable food products with an elongated cantilever arm rotatably attached to a support shaft. The cantilever arm having a marking roller adjacent one end and a counterweight slidably carried by the arm. The marking roller having a wheel with a plurality of teeth extending generally radially outwardly of the wheel for marking the food product.

Abstract: A gyro compass having a gyro case housing therein a gyro and supported with freedom of three axes, functions for outputting a signal corresponding to an inclined angle of the gyro spin axis relative to the horizontal plane and a function for applying a torque around a vertical axis of the gyro case in proportion to an input signal, and a controller supplied with the signal corresponding to the inclined angle and a latitude value at which the gyro compass is located, wherein a constant relative to the input latitude value is set by the controller after the gyro compass is energized, a signal, which results from differentiating the signal corresponding to the inclined angle during a predetermined time, is added to a signal, which results from multiplying the signal corresponding to the inclined angle with the constant and an added result is set as the input signal, whereby a constant optimum north-seeking movement is carried out regardless of the change of the latitude value to thereby reduce a settle time.

Abstract: A gyro compass having a gyro case housing therein a gyro whose spin axis is held substantially in the horizontal plane, a supporting device for supporting the gyro case with freedom of three axes and means for applying a torque proportional to an inclined angle of the gyro spin axis relative to the horizontal plane around a vertical axis of the gyro case perpendicular to the spin axis is disclosed in which there are provided a detecting device for detecting an inclination angle of the spin axis relative to said horizontal plane, torquer for applying a torque to the gyro case about its vertical axis, and an acceleration error controlling device for receiving an output signal from the detecting means and for controlling the torquer such that the torquer produces a predetermined torque to be applied to the gyro case about its vertical axis.

Abstract: A sheet-driven type automatic drafting machine has a drive roller or rollers and a rotary drive mechanism connected to the drive roller or rollers, a Y-axis rail extending in the Y-axis direction above the drive roller or rollers, a line-drafting head movably mounted on the rail for movement along the rail and a head driver connected to the head for driving the head along the rail, a shaft positioned above the roller or rollers and parallel to said rail, a first press roller arm pivotally mounted on the shaft for pivoting around the shaft at a predetermined position thereon, a second press roller arm pivotally mounted on the shaft for pivoting around the shaft and for movement along the shaft, the press roller arms each having a press roller at one end thereof engagable with the drive roller or a corresponding drive roller when the press roller arms are pivoted toward the drive roller or rollers for pressing a drafting sheet therebetween and enabling the drafting sheet to be driven in an X-axis direction by t

Abstract: In order to eliminate gyro errors of electrically caged, two-axis gyros, which have a pick-off (52,54) and a torquer (46,48) on each input axis, and each pick-off (52,54) arranged on one input axis energizes the torquer (48,46) on the other input axis, a first measurement is made with a first direction of rotation of the gyro rotor (42). Subsequently, for a second measurement, the direction of rotation of the gyro rotor (42) is reversed and, at the same time, the polarity of the signals from the pick-offs (52,54) is inverted. A measuring value is formed from the gyro signals obtained with both of these measurements.

Abstract: In an azimuth signal generator for an automobile navigation system a change in the rotational rate of an inertia rotary member, which has its rotary shaft held vertically and is driven at substantially a constant speed, is detected as a direction changing rate of the car and the direction changing rate is integrated by an integrator to obtain an azimuth signal. On the other hand, the azimuth of geomagnetism is detected by a geomagnetic azimuth sensor and a correcting signal is produced based on an error between the azimuth signal and the geomagnetic azimuth signal. The correcting signal is negatively feedback to the input side of the integrator, causing the azimuth signal to follow the geomagnetic azimuth signal.

Abstract: A tire building machine for marking the centerline of a continuous piece of plystock is described as having, (I) a carriage which is movable along a trackway which is normal to the direction of travel of the piece of plystock being marked, (II) a pair of sensors carried by the carriage for monitoring the opposing marginal edges of the piece of plystock, (III) a device centrally disposed on the carriage between the sensors for marking the centerline of the plystock, (IV) a mechanism for adjusting the spacing between the sensors when the width of the plystock varies, and (V) a mechanism for moving the carriage and attached sensors, in unison, along the trackway, when the piece of plystock wanders from the pathway which the sensors are initially set to monitor.

Abstract: Disclosed is an improved apparatus for scoring glass wherein a scoring wheel is rotatably mounted on an axle within a novel mounting bracket. The mounting bracket can be the extension of the handle of a manual glass scoring device or integrated within a cartridge for an automated or semi-automated glass scoring machine. One of the unique features of the improved apparatus of this invention resides in the spatial geometry of the clearance between the mounting bracket and the scoring wheel. The enhanced degree of clearance between these two components substantially reduces maintenance requirements and improves consistency of performance. This results in reduction in accumulation of glass chips between the wheel and the mounting bracket, thereby insuring continuous freedom of movement of the scoring wheel within the bracket even after extended periods of use. Such enhanced clearance also enables simple and precise lubrication of the axle which supports the scoring wheel.

Abstract: A marine gyro compass output is corrected to take account of accelerations cting upon the ship in which it is installed by calculating about once per second a correction capable of expression by differential equations which are solved by numerical methods by taking small but finite time increments to linearise the equations with regard to time, the current calculated correction factor being applied to correct the gyro compass output many times per second. The corrections can take into account (a) ship north-south acceleration, (b) change in Coriolis acceleration, (c) earth rotation rate and (d) azimuth error for east-west speed. Furthermore, account can be taken of the constant characteristics of the particular gyro compass to be corrected in terms of its tilt limit, its period of damped oscillation, its damping and the characteristics of the compass electrolytic level which determines tilt.

Abstract: The present invention provides a glass scriber assembly having a base, a support attached to the base and wherein the support includes an upper surface adapted to support a pane of glass. An elongated arm is pivotally mounted to the base so that one end of the arm is positioned over the support surface. A conventional glass scriber is detachably secured to the end of the arm so that the scriber engages a pane of glass on the support surface. Simultaneously, a compression spring in between the other end of the arm and the base urges the scriber against the glass pane. A roller is rotatably mounted to the support and abuts against the bottom of the glass pane on the support surface so that, upon manually rotating the roller, the roller moves the glass pane under the glass scriber.

Abstract: A gyrocompass has a gimbal (18;218) rotatable about an upright axis (22;222) and a gyro (10;210) rotatably mounted in this gimbal (18;218) about an inner axis (16;216) transverse to the upright axis (22;222). The gyrocompass also includes a level sensor (30,32;230,232) supported by the gimbal (18;218) for providing a level signal signifying the tilt of the upright axis (22;222) from vertical. Also included is a controller (50) connected to the level sensor (30,32;230,232). The controller includes equipment (50) responsive to the level signal for rotating the gimbal (18;218) into an initial position (SP(1)) at which the level signal has a predetermined value. A method employing the foregoing apparatus includes the steps of rotating the gimbal (18;218) until the level sensor (30,32;230,232) indicates the inner axis (16;216) is horizontal.

Abstract: A gravity gradiometer disposed upon a gyroscopically stabilized platform in a vehicle can be modified, without impairment of its normal operation, to perform compassing functions.

Abstract: A gyrocompass including a first gimbal, a gyro motor mounted in the first gimbal and including a gyro rotor mounted to rotate about a horizontally alignable spin axis, a pendulous body in which the first gimbal is mounted to be rotatable about a vertically alignable axis of rotation, a housing in which the body is rotatably suspended, a verticality device associated with the body for allowing the body to assume an orientation in the housing in which the axis of rotation is vertical, and a follow-up device including a pickup mounted for sensing the angular position, about the axis of rotation, of the gimbal relative to the body and a drive connected for rotating the body relative to the housing about the axis of rotation in dependence on the position sensed by the pickup. The drive can be constituted by a stepping motor constructed to rotate in highly uniform steps and simultaneously serving to provide an indication of the angular position of the body relative to the housing about the axis of rotation.

Abstract: In a vehicle locating apparatus that utilizes Hall effect generators to determine the magnetic heading of the vehicle there is provided magnetic compensation by the placing of a coil around the Hall generators. A current source generator provides power to the coil of such magnitude so as to create a magnetic field which cancels the spurious local magnetic field components. The appratus also includes a set of manual switches to program a constant number into the system. The system incorporates this number to compensate for variable wheel diameters and to allow the selection of variable map scale units. This number is utilized by the system in a division technique that repeatedly subtracts the number or adds the number to the accumulated distance traveled by the vehicle. The location of the vehicle is updated as the vehicle passes a transmitting signpost. Data transmitted to and from the vehicle locating apparatus is in a self-clocking format that reduces oscillator accuracy requirements.

Abstract: The gyrocompass includes an improved indexing mechanism whereby the mechanical position of the gyroscope casing with respect to two orthogonal components of input rate may be measured.

Abstract: Disclosed is apparatus and method for accurately determining the direction of true north or the change in drift of other gyroscopes. The apparatus comprises a single degree of freedom gyroscope driven by a permanent magnet electric motor. The gyroscope rotor is spun by the motor at varying speeds and the torque required to maintain the rotor at a null orientation is measured and recorded. The measured torques are processed to produce an accurate indication of true heading or to indicate the change in the level of drift of other gyroscopic instruments.

Abstract: An automatic rate range switching and control system adapts the full range of an analog output signal of a gyroscopic rate sensor to a range consistent with the precision conversion thereof into a digitally compatible signal. In a digital strapped down inertial reference system, for example, a plurality of strapped down, force-rebalanced rate sensors is used to sense aircraft body rates, wherein each gyro pick off signal is fed back to the gyro torquer in a manner to maintain the pick off signal essentially null, the torquer current signal thus being proportional to the sensed aricraft rate. The full range of the gyro's rate sensing capability may extend from zero to several hundred degrees per second. However, with the present invention, the switching and conversion of the analog rate signal into a digitally compatible signal is necessary only over a limited range.

Abstract: A miniature automatically self-aligning azimuth reference employs a floated pendulous gyrocompass device for the rapid determination of geographic north as required for surveying purposes. Fast alignment with north from an initially misaligned condition is effected in an iterative manner through the action of a unitary vertical-axis magnetic centering-torquer-pick off system employing eddy current forces.

Abstract: A calibration system produces a calibrating signal having an adjustable amplitude, a torque force representative of that amplitude is directly applied to a meridian seeking gyroscope unit that hangs from a suspension band. Prior to each use of the instrument, the signal amplitude is adjusted so the gyroscope unit assumes a predetermined null position. The torque force is applied to the gyroscope unit by inductive field interaction of the first, second, and third coils. A control signal representative of the displacement of the gyroscope unit from the null position is applied to the third coil, which is fixed relative to the null position. The calibrating signal is applied to the first coil, which is also fixed relative to the null position. The axis of the first and third coils are both in an approximately perpendicular relationship to a vertical axis.