Abstract: A vehicle compass includes a magnetic field sensor for mounting within a vehicle and providing two output channels of information representing orthogonal direction sensing of the earth's magnetic field within the vehicle. The sensor is coupled to an electrical circuit including a microprocessor for sampling the data from each of the two channels and providing a plurality of tests to determine if the rate of change of data is within a prescribed limit thereby indicating valid data is being received. Further, the data is tested to determine the maximum and minimum signal levels during movement of the vehicle through a completed 360.degree. path of travel and for calculating therefrom the compass compensation information used to provide a corrected heading display.

Abstract: A fluxgate magnetometer having wide temperature range accuracy, without adding temperature compensating components, is obtained by: (1) a fluxgate adjusted by aligning a permeable magnetic tape core relative to the secondary winding of the fluxgate so as to substantially equalize each of the pulses induced in the secondary winding by the transition from core saturation to unsaturation in both directions, and (2) increasing the fluxgate magnetometer primary drive current above what is normally considered saturation current to reduce sensitivity of the output to temperature and primary drive changes.

Abstract: An electronic digital compass utilizes an amorphous magnetostrictive wire 100 exhibiting reentrant behavior as a core. A sense wiring 104 is wrapped about the core and the core is driven with a triangular wave through a drive coil 102. The earth's magnetic field biases the core 100 such that when the core 100 is driven to reentrant jumps the time duration between adjacent pulses induced into the sense winding 104 is related to the heading. A pair of such arrangements are used in physical 90 degree relationship to resolve ambiguities in heading angle. The resulting heading angle calculation is a true digital product which is independent of analog amplitude variations and requires little or no adjustment for high accuracy.

Abstract: A terrestrial magnetic sensor has a bobbin body having a magnetic core inserting groove, a silicon gel filled in the magnetic core inserting groove, a magnetic core buried in the silicon gel filled in the magnetic core inserting groove, and a bobbin cover for closing the magnetic core inserting groove of the bobbin body. Thus, this terrestrial magnetic sensor can suppress the decrease in the magnetic permeability by burying a magnetic core in a silicon gel and can be hardly affected by the influences of the variations in an environmental temperature and an external stress.

Abstract: A hand bearing compass comprises an electronic direction finding sensor fixed in a flat rectangular compass body. An actuating button causes the sensor to measure a magnetic bearing in dependence on the orientation of the compass body in a horizontal plane; measured bearings are stored in microprocessor memories for subsequent sequential recall to a display. To align the sensor horizontally in use the compass has longitudinal sights for visual alignment with a mark and a flat upper surface of the compass body for alignment with the horizon to facilitate levelling. Actuator and longitudinal sights are laterally spaced to avoid obscuring the latter, and arranged symmetrically about a median plane of the body so that use is possible in either hand.

Abstract: A fluxgate magnetometer includes a body of magnetic material, a drive coil and a sensing coil. At least one of the drive coil and the sensing coil is composed of two portions, each of the two portions being disposed in generally parallel planes which are spaced apart and respectively include an electrically insulating substrate and a spiral shaped portion which is electrically conductive supported by the electrically insulating substrate, the two portions being electrically connected such that electric current flows in the respective spiral shaped portions in opposite rotational senses relative to the body of magnetic material.

Abstract: An applied magnetic field direction indicating device comprising a magnetic sensor (1) having an omnidirectional characteristic and an output which is non-linearly related to the magnitude of the applied field. The sensor (1) is subjected to two mutually perpendicular sinusoidal magnetic biassing fields of the same frequency and in time quadrature relationship. A characteristic of the output of the sensor (1) is indicative of the direction of the applied field.

Abstract: In a location detecting apparatus which detects the location of a moving body on the basis of the heading signal from a terrestrial magnetism heading sensor attached to the moving body and the rotational angle signal from a rotational angle sensor attached to the moving body, a correcting method for correcting errors in a terrestrial magnetism heading sensor, comprising the steps of: detecting the amount of a heading change of the moving body that is made when the moving body turns a curve, and detecting a magnetized amount of the moving body on the basis of the detected amount of a heading change, an output from the terrestrial magnetism heading sensor before the heading change is made and an output from the terrestrial magnetism heading sensor after the heading change is made.

Abstract: A magnetometer having only a single coil winding for sensing the magnetic field along a single axis. Functionally, the invention comprises an oscillator, and means for measuring the duty cycle thereof. The oscillator uses a saturating inductor which also serves as the magnetic-field-sensing element. The inductor is driven with a position voltage and when the current through the inductor exceeds a value which indicates that the core is saturated, the driving voltage switches to an equal-magnitude negative value. This negative drive is maintained until the current again indicates the core to be saturated, at which point the driving voltages switches back to the positive value. With no externally applied field, the inductor current averages to a zero value and the duty cycle of the driving voltage is fifty percent. An externally applied field helps the core saturate in one direction and hinders it in the other, resulting in a change in average inductor current and drive duty cycle.

Abstract: A toroidal or similar body (1) of a non-magnetic, insulating material, preferably glass fibre-reinforced plastic or ceramic is provided with at least three recesses for receiving in each case a corresponding one magnetoresistive sensor. The associated measuring directions of said sensors are orthogonal to one another. For producing a magnetic auxiliary field applied to the sensors, a coil is arranged on the body. for increasing the accuracy and reliability of the measured result, the body is provided with at least one further recess for receiving a further sensor. The measuring direction of the further sensor differs from that of other sensors and forms preferably the same angle with the other measuring directions. The body can be in multipart form and is in particular made from two identical parts.The apparatus can be used in electronic compasses and for north finding devices.

Abstract: The method and system described herein calls for the calibration of an electronic compass without using the operator of the vehicle in the process. This eliminates the need for the operator of the vehicle to help to supply information relating to the earth's unknown magnetic field as sensed from the frame of reference of the vehicle in which the electronic compass resides. The method does not need to make use of the unknown magnetic field due to the earth (as sensed from the frame of reference of the vehicle in which the electronic compass resides) in the process of automatically calibrating the compass. This magnetic field, although unknown, is utilized by viewing the position of the vehicle with respect to the earth's field, thereby eliminating the effect on the compass computation of the earth's magnetic field as sensed in the vehicle.

Abstract: A compass dither device for use with a magnetic compass heading sensor unit for marine seismic streamers and the like having interrogating circuitry associated with the heading sensor to periodically provide a trigger pulse for interrogating a compass heading sensing components in the heading sensory unit and provide compass heading signals indicative of the heading of the compass the the time of interrogation, the compass dither device including a housing for the magnetic compass heading sensor unit having a dither coil encircling the portion where the headings sensory unit is positioned.

Abstract: A fluxgate compass direction sensor in which a fluxgate is mounted relative to a receptacle by means of a flexible circuit. The fluxgate is also suspended in a liquid by means of a float. In use, if the receptacle tilts relative to the horizontal, the level of the liquid will move to retain a horizontal aspect and the float, being buoyant in the liquid, will retain the fluxgate in the horizontal plane. The flexible circuit acts to allow tilting of the float and fluxgate relative to the receptacle while retaining the fluxgate in lateral and directional alignment relative to the receptacle.

Abstract: An electronic compass and method. The electronic compass includes circuitry for generating a control signal and circuitry responsive to the control signal for producing reference signals having a frequency established by the control signal. The compass also includes circuitry for phase shifting the reference signals to generate an output signal shifted by a phase shift which is a function of the angle between a reference heading of the compass and the direction of the magnetic flux lines of the earth's magnetic field in a local area. Further, the compass includes circuitry for monitoring the frequency of one of the reference signals, for varying the control signal to thereby cause reference signals having a predetermined frequency, and for measuring the phase shift between the monitored reference signal and the output signal to calculate the angle between the heading of the compass and the direction of the magnetic flux lines of the earth's magnetic field in a local area.

Abstract: A compass, by which under-water divers can find their direction, comprise two crossed flux-gate type magnetometers, the measurements of which are processed by logic signals to light up a set of light-emitting diodes which indicate the right direction and, if necessary, the direction and approximate value of the offset of the compass. By using non-magnetic materials and low-consumption electronics, the disturbance of the local field is considerably reduced as compared with a conventional compass. This enables divers to avoid triggering magnetically fired mines.

Abstract: A correction apparatus for an azimuth calculation system which includes an azimuth sensor mounted on a moving body for producing two mutually perpendicular magnetic field components relative to the earth's magnetism acting thereon, and wherein the azimuth sensor is moved in a full circle so that an azimuth circle is formed by the two magnetic field components.

Abstract: A magnetic sensor including an annular iron core, an annular hollow bobbin for a primary winding which incorporates therein the annular iron core, the bobbin having a plurality of protruded portions which are arranged along a circumference of the annular bobbin with an equal distance, each of the protruded portions being extended in a direction parallel to a center axis of the annular iron core, the primary winding being wound on the annular bobbin at respective portions between adjacent protruded portions with an equal number of turns, a bobbin for a secondary winding having a positioning means for the primary winding in association with the protruded portions of the bobbin for the primary winding when the bobbins for the primary and secondary windings are assembled, the secondary winding being wound on the bobbin to form more than two pairs of winding groups.

Abstract: Disclosed is an azimuth determination apparatus attached to a motor vehicle for determinating the forward direction of the vehicle. The azimuth determination apparatus includes an azimuth sensor for generating orthogonal first and second signals indicative of the forward direction of the vehicle. Two azimuth vectors are obtained on the basis of the orthogonal first and second component signals, first components of the two azimuth vectors being maximum and minimum. The determination is made in terms of the fact that the difference between second components of the two azimuth vectors is below a predetermined value. In accordance with the determination, the orthogonal first and second component signals are corrected on the basis of said two azimuth vectors so that the accurate moving direction of the motor vehicle can be obtained irrespective of the remanence of the vehicle.

Abstract: A quick ranging technique controlled by a microcomputer, makes predetermined stepped adjustments to the charge times in a ranging circuit to bring the charge time into a required range, thusly minimizing calibration time for an electronic compass; a digital filter also controlled by the microcomputer smooths out the magnetic field component signals.

Abstract: An azimuth calculation apparatus includes an azimuth sensor mounted on a moving body for detecting a direction of the moving body, the azimuth sensor having an excitation winding wound on an annular magnetic core and a pair of output windings wound on the core perpendicularly relative to one another to produce first and second output signals therefrom in response to energization of the excitation winding. The calculation apparatus is arranged to detect a temperature of the azimuth sensor and to determine a pair of correction values based on the detected temperature of the azimuth sensor so as to correct each value of the first and second output signals from the output windings to an optimal value for calculating the direction of the moving body in dependence upon the corrected output signals from the output windings.

Abstract: A direction sensor includes at least one sensor element including a ring-shaped core formed from at least one flexible wire made of zero-magnetostrictive amorphous magnetic material, two pairs of series connected coils spaced from each other at equal intervals about the core for sensing an external magnetic field, with the core being formed by threading the wires through the coils, the coils being excited by an alternating frequency f, wherein voltages of frequency f are produced across each pair of coils; and a process circuit for providing a differential voltage between the voltages of frequency f produced across each pair of coils.

Abstract: A method for establishing the driving direction of a motor vehicle is suggested with an electronic compass which is provided with a magnetometer having two probes being turned by 90.degree. with respect to each other and an evaluation circuit. For establishing the ground field (He) and its angle (.phi.') in a vector diagram (X,Y) at first the measuring points (M1 . . . M4) with the maximum and minimum values (x,y) of the elliptical polar frequency (O) of the magnetic field (H) measured on the magnotemeter by turning the vehicle are picked up and from this the vector of a fixed interference field (Hs) with the coordinates of the center point (P) is established as a parameter of the polar frequency (O). Thereafter, the measuring points (M5 . . . M8) of the magnetic field (H) with the maximum and minimum distances of the points on the polar frequency (O) with respect to its center point (P) are picked up and from this the length of the semiaxis (a,b) are established as parameters of the polar frequency (O).

Abstract: A magnetometer (11) for time coded measurement of magnetic fields, which comprises at least one sensor (15) having a magnetizable, rod-shaped core (20) and a winding (19) disposed on the core. To generate an auxiliary alternating field, the winding (19) carries an alternating current, which together with the magnetic field that is to be measured generates in the winding a measurement voltage, the positive and negative half-waves of which deviate from one another as a function of the magnitude of the magnetic field that is to be measured. To attain a simple and accurate evaluation of the measurement voltage, this measurement voltage is applied to the input of the limit-value switch (25), the output (26) of which produces a rectangular voltage, the duty cycle of which directly represents a measure for the magnetic field detected by the core (15) of the sensor.

Abstract: In a process for establishing the driving direction of a vehicle by an electronic compass fixedly mounted in the vehicle and which is provided with a magnetometer having a computerized evaluation circuit the local curve (O) of the earth field (He) is determined from five measuring points (M1 . . . M5) which are established by turning the vehicle and corresponding signals are stored. The parameters for the center point displacement (Hs), the shape (ellipse) and the turning (angle .alpha.) of the local curve (O) in the vector diagram (x,y) are calculated by the computer by means of an algorithm with five unknowns for the five measuring points and thereafter the direction of the earth field (He) is computed. Subsequently, the vehicle is oriented to a predetermined cardinal direction and a correction angle is determined from the difference of angles between the cardinal and north directions and the earth's magnetic field direction measured by the compass.

Abstract: A magnetometer with a time coding is proposed, which serves to measure magnetic fields in the motor vehicle and in particular to measure the direction of the earth field and to determine the driving direction. The magnetometer includes at least one sensor having a horizontally disposed, magnetizable rod-shaped core and a winding disposed on the core. The winding carries an alternating current for generating an auxiliary alternating field, in order to magnetize the core in alternation up to and into saturation. In order to measure the magnetic field detected by the sensor and to generate the auxiliary alternating current, a controlled alternating current source (18) is connected on the one hand to one and the same winding (19), and on the other hand a measurement voltage that can be picked up at this winding (19) is connected to an evaluation circuit (21, 25, 12, 13).

Abstract: A calibration sequence and method for use with an electronic compass which allows for the separation of the vehicle's magnetic field from the earth's magnetic field so that the earth's field can be measured and used to give vehicle direction; such calibration sequence being done with a mirrored 180 degree re-orientation of the vehicle.

Abstract: A method and apparatus for providing a magnetic compass, and system to accurately calibrate the compass with a rotation of the vessel on which the compass is mounted through a single rotation of 360 degrees. The compass comprises gimballed field sensing elements, and processor to provide a signal which is corrected for compass offsets, for permanent magnetic field anomalies and for induced magnetic field anomalies.

Abstract: An electronic display device for presenting directional information to the operator of a motor vehicle. The display simultaneously shows current vehicle direction of travel as well as the relative directions of the 4 major compass axes by converting the direction information from an electronic flux gate compass. The device is further optimized to reduce the number of pin connections to the display and associated driver complexity and is readily applicable to LED, LCD or vacuum fluorescent type display elements.

Abstract: An electronic magnetic compass for computing the magnetic heading of a vehicle, such as a tank, having two iron bodies relatively movable with respect to each other about a vertical rotary axis comprises: a non-pendulous triaxial magnetometer outputting magnetic field electrical signals representing the three axial components of the magnetic field at the location of the magnetometer; sensors outputting electrical signals representing the pitch and roll of the vehicle body on which the sensors are mounted; an angle measuring device for outputting electrical signals corresponding to the angle of rotation between the two bodies; a memory for storing a plurality of pre-calibrated correction factors for correcting the effects of the permanent magnetic field and the induced magnetic field on the measurements of the magnetometer for each of a plurality of angles of rotation between the two bodies; and an electronic computer for computing on a real-time basis the magnetic heading of both bodies from the magnetic fiel

Abstract: An aircraft heading correction system utilizing the horizontal field strength of the earth's magnetic field to determine the tangent of the dip angle generally associated with a given field strength. The tangent of the dip angle is then used to generate a signal which corrects the flux valve heading during accelerated flight.

Abstract: Multiplexing a bandpass filter circuit to work with a flux-gate sensor output to minimize the amount of electronic circuitry required to work with the control system and to reduce the effect of gain on the circuit by emphasizing repeatability.

Abstract: An electrical drive dircuit for a flux-gate magnetic sensor used in a digital compass for a vehicle provides signals for application to the primary of a flux-gate sensor to assure the core is saturated at a predetermined time during each cycle of the drive signal.

Abstract: A current location updating display for indicating the current location of moving members such as an automobile while updating from time to time based on output from a magnetic azimuth sensor adapted to detect the azimuth of terrestrial magnetism. Output signals from the magnetic azimuth sensor are stored in a data memory after A/D conversion and correction, and a predetermined amount of data read out from the data memory is subject to the averaging processing. With this, plural angle information (sin .theta. and cos .theta.) signals or plural angle (.theta.) signals are averaged out including a signal corresponding to disturbance magnetism. Thus average data signals are integrated by an integrator and then sent to a display portion. Through the averaging processing an azimuthal error is restrained as small as possible, so that the current location or running path of the moving member may be indicated correctly.

Abstract: In a zigzag running warning system for automotive vehicles which detects and gives a warning of zigzag running of a vehicle, a terrestrial magnetism sensor generates an electric signal having an amplitude varying in dependence on the direction of travel of the vehicle with respect to the direction of the terrestrial magnetism. An electronic unit in the system discriminates that vehicle is running in a zigzag direction when the amplitude of the electric signals changes in excess of a predetermined value at a period which is less than a predetermined time, and informs the driver of the zigzag running by a speaker, lamp or the like.

Abstract: Electronic equipment has, in its case, a flux gate magnetic sensor with an excitation coil and a sensing coil wound around an annular magnetic core made of high permeability material, an integrated circuit including a magnetic field detector, cooperating with the magnetic sensor for detecting an external magnetic field and an operation circuit for operating the geomagnetic direction, a display device for displaying at least the geomagnetic direction, and a power source battery. The flux gate magnetic sensor is arranged along the inner surface of the case and the battery is arranged within the annular magnetic core of the magnetic sensor.

Abstract: A solid-state heading sensor is comprised by a three-axis Hall effect magnetometer and a three-axis accelerometer. The magnetometer is comprised by a cube-like structure (10) of non-magnetic material on each of three orthogonally related faces of which is located a respective Hall effect device (11, 12, 13), for example of GaAs. The three-axis accelerometer may be comprised by a three-axis module (15) disposed in a recess in the cube-like structure, or by three separate accelerometer structures (23, 24, 25), for example planar etched silicon accelerometers, each disposed on a respective one of the orthogonally related faces adjacent the Hall effect device (20, 21, 22) thereon.

Abstract: A flux gate sensor having sense windings for providing an output proportional to the strength of an external magnetic field in which the sensor is placed. A gating circuit which is responsive to a pulse which is generated when the core of the sensor is driven into and out of saturation gates the output of the sense windings to a pair of filters which in turn provide an output proportional to the intensity of the external magnetic field. With two sense windings the outputs of the filters may be used to determine the direction of the magnetic field relative to the sensor and thereby be used as a compass.

Abstract: A system for accurately measuring the direction in which a magnetometer is to be set has a simple construction and is little affected by iron structures on a hull. The system has a magnetometer which includes an excitation source, a magnetic core, an excitation AC winding and an output winding which are both wound around the magnetic core. The output winding is composed of two series connected coils which are wound around the magnetic core and have an equal number of turns. The measuring system applies an alternating current to the core having an amplitude large enough to saturate the magnetic core, and obtains an output from the output winding corresponding to the angle formed between the geomagnetic field direction and an imaginary line obtained by interconnecting the point of connection of the two coils and the central point of the magnetic core.

Abstract: A self-resonant magnetometer using the inductance and interwinding capacitance of a sense winding to establish the frequency of operation. A sense winding signal is amplified to provide a driver current for a driver winding. The driver winding current with the addition of a dc offset current causes the mu (permeability) of a ferrite core to vary in a non-linear region of its B/H curve. The change in the mu of the ferrite core produces a change in flux in the magnetic core if an external magnetic field is present. This change in flux induces a signal in the sense winding.

Abstract: A drive guide system for an automotive vehicle indicates the remaining distance to a destination and the direction to the destination. In order to indicate the remaining distance and the direction in which to travel, travelling direction and travelling distance are detected. A direction sensor for detecting the terrestrial magnetic field is employed in the drive guide system. The direction sensor can be easily influenced by background noises in its surroundings. The background noise thus affects the detection of the direction of the terrestrial magnetism and thus causes errors in the calculation of the remaining distance and the direction to travel. Therefore, the variation of the background noise is sequentially monitored to detect the magnitude of the background noise affecting the detection of the direction, and when the variation exceeds acceptable limits, an error signal is produced.

Abstract: A fluxgate magnetometer with a linear array of three sensors equi-spaced along a support beam and accurately adjustable into the same spatial orientation for sensing magnetic field anomalies and/or for measuring a single axis component of a magnetic field at two or more points in space. The beam is mounted in an elongate housing provided with pairs of wedges, acting in opposition to one another at opposite ends of the beam, for flexing the beam to adjust the sensors, which have drive windings in containers secured to the beam, the drive windings being rotatably adjustable in their containers relative to sense windings and feedback windings.

Abstract: A magnetic direction sensor having a head constituted by a magnetic wound core composed of a ferromagnetic metal ribbon; a winding for exciting the magnetic wound core; a first output winding wound around the core such that it encircles two opposite portions of the core and a second output winding wound around the core at a certain angle with the first output winding such that it encircles two other opposite portions of the core; the first and second output windings providing output signals for determining the direction of the external magnetic field with respect to the head, and the inner and outer ends of the ribbon overlapping each other circumferentially by a certain angle .theta. may be between 0.5 and .theta..sub.max satisfying the equation: .theta..sub.max =1/4D+1.5.alpha.+1 wherein D represents the outer diameter of the core and .theta. represents a desired direction accuracy. This structure of the sensor head enables it to obtain a high direction accuracy.

Abstract: Sensors mounted in detachable modules are located at selected positions along a cable, such as one used in marine seismic exploration, adapted to be towed behind a vessel in a body of water. The sensors are selectively addressable, either individually or as a group, by coded signals sent through the cable. When addressed, the sensors provide readings of the earth's magnetic field vector. The readings are used to provide an indication of the position of the sensors and thus the cable relative to the towing vessel. Cable depth readings may also be made by the sensors.

Abstract: A drive circuit applies an oscillating signal to the drive coil of the fluxgate thereby generating output pulses from the detection coils of the fluxgate, which pulses have an area proportional to the magnetic flux through that coil. The output pulses are integrated sequentially by an integrator. The output may be used directly to obtain the orientation of the fluxgate, and hence of a vessel in which the fluxgate is mounted but it is preferable on the grounds of accuracy and speed of response to apply a predetermined number of pulses from each detection coil, apply a constant signal to the integrator and measure the times between the application of that constant signal and the integrator output attaining a predetermined value. This may be measured digitally giving a more accurate measurement of the fluxgate orientation. Suitable error elimination means may be provided.

Abstract: A device and method for detecting the running direction of an automotive vehicle includes terrestrial magnetic field direction detection, vehicle steering angle detection, and response to the signals of these detectors for producing the vehicle running direction signal. In a computer, or equivalent circuitry, occurrence of abnormalities of the terrestrial magnetic field is decided when the relationship between the change in the vehicle running direction and the change in the steering angle does not satisfy a predetermined requirement.

Abstract: The system of the present invention provides an electrical digital compass for use in a vehicle which includes a unique compensation and variation correction control which is readily set by the vehicle operator with the operation of push-button switches. The electrical display system and circuitry includes a microprocessor for comparing the information from a magnetic field sensor when the vehicle is aligned in a magnetically known direction and for providing a correction signal to assure the displayed output corresponds to the predetermined magnetic field alignment. In areas where magnetic variation is significant, the system generates, stores and processes a correction signal to assure the displayed output corresponds to the true heading of the vehicle. In one embodiment of the invention, a temperature sensor is provided to indicate the ambient temperature in which the vehicle is operating and which is digitally displayed to the operator.

Abstract: An electronic compass for vehicles comprising at least two magnetic sensors arranged in use to be respectively responsive to orthogonal horizontal components of a magnetic field which includes the earth's magnetic field and a spurious magnetic field which is associated with the vehicle, for producing electrical signals corresponding to said components, data storage means arranged to store signals derived from the sensors as the vehicle is rotated in the horizontal plane during a compass setting cycle, and signal processor means responsive to electrical signals produced by the sensors after the setting cycle has been completed and to the signals stored during the setting cycle, for providing output signals indicative of the bearing appertaining to the heading of the vehicle in which the effects of the spurious magnetic field are compensated for.

Abstract: An electronic compass for vehicles comprising three magnetic sensors arranged in use to be respectively responsive to orthogonal components of a magnetic field which includes the earth's magnetic field and a spurious magnetic field which is associated with the vehicle, for producing electrical signals corresponding to said components, tilt sensor means responsive to vehicle tilt with respect to the horizontal plane, data processor and storage means arranged to store signals derived from the sensors as the vehicle is turned through a compass setting cycle, and signal processor means responsive to electrical signals produced by the sensors after the setting cycle has been completed and to the signals stored during the setting cycle, for providing compensated signals related to the bearing appertaining to the heading of the vehicle in which the effects of the spurious magnetic field are compensated for and further processor means to which the compensated signals are applied and which is responsive to the tilt se

Abstract: A mount for an earth magnetism sensor device for use in a bearing detecting apparatus which is to be provided on an automotive vehicle adapted to detect a horizontal component of the earth magnetism, characterized in that an axis of detecting a primary direction of the earth magnetism sensor means is offset in the horizontal direction in coincidence with an extent of magnetic declination at a given spot of observation with respect to a desired orientation by way of a map.

Abstract: Mounting structure for a flux-gate sensor used in electrical digital compass for a vehicle includes a cradle assembly for pivotally mounting the sensor for adjustable movement in a vertical plane aligned with the longitudinal axis of a vehicle. A housing includes an arm engaging the cradle assembly for automatically pivoting the sensor to a horizontal position when installed in different vehicles.