A method (100) for calibrating a plurality of sensors (21-24) each comprising a magnetometer (31), a gyroscope (32) and an accelerometer (33), the method comprising: providing (111) a first device (10) comprising at least one cavity (15-18) adapted for introduction of one or more sensors (21-24); introducing (112) each sensor of the plurality of sensors (21-24) into the first device (10); transmitting (113), from each sensor of the plurality of sensors (21-24) to a computing apparatus (40), a first measure corresponding to the respective magnetometer (31); determining (114), the computing apparatus (40), whether differences between the first measure of each sensor and the first measure of the other sensors of the plurality of sensors (21-24) are lower than a predetermined threshold; and calibrating (115) the plurality of sensors (21-24), if at least one of the differences between the first measures is equal to or greater than the predetermined threshold, by rotating the first device (10) or a second device (10) with the plurality of sensors (21-24) introduced therein, the second device comprising at least one cavity (15-18) adapted for introduction of one or more sensors (21-24). Also, a system (5) for calibrating a plurality of sensors (21-24).

A computer-implemented method includes, by one or more processors in electronic communication with a tunneling magnetoresistive sensor, wherein the tunneling magnetoresistive sensor is a component of a magnetic storage drive configured to read magnetic data from a magnetic storage medium, detecting a short across the tunneling magnetoresistive sensor, measuring a change in resistance of the tunneling magnetoresistive sensor, measuring a change in voltage amplitude for the tunneling magnetoresistive sensor, and dividing said change in voltage amplitude by said change in resistance to yield a ratio. The computer-implemented method further includes, responsive to the ratio being greater than a predetermined ratio threshold, determining that the short is caused by a magnetic shunt. A corresponding computer program product and computer system are also disclosed.

A learning system (1) for vehicles for learning a neutral point of a measurement sensor equipped in a vehicle by using a magnetic marker disposed in a traveling road includes a sensor unit (11) which detects the magnetic marker and measures a lateral shift amount of the vehicle with respect to the magnetic marker, a route information acquiring part which acquires route information indicating a shape of the traveling road, and a learning determination part which determines whether a learning condition as a condition for performing learning of the neutral point of the measurement sensor is satisfied, wherein a fluctuation range of a lateral shift amount measured by the sensor unit (11) when the vehicle is traveling a learning road as a traveling road in a constant shape is equal to or smaller than a predetermined threshold is set at least as the learning condition.

A method for adjusting operation of a motion tracking system having a computing device and sensors, wherein each sensor includes a magnetometer, a gyroscope and an accelerometer, includes the following steps: receiving, the computing device, a magnetic field measurement from each of the sensors; digitally processing, the computing device, each of the magnetic field measurements in order to determine if a difference of intensities and/or inclinations of at least one pair of magnetic field measurements exceeds a threshold value, and/or if an x,y point with the differences of intensities and inclinations as coordinates thereof falls outside of a threshold area; and adjusting the operation of the motion tracking system if at least one difference exceeds the threshold value and/or the x,y point falls outside of the threshold area.

Methods, apparatus, and systems for medical procedures are disclosed herein for receiving an input of a plurality of measured coordinates of a respective plurality of position transducers of a probe inside a body of a subject, receiving a measured voltage measurement output by the probe, determining a cost function based on a model of known mechanical properties of the probe compared to the measured coordinates with respect to shapes that can be assumed by the probe in the body and further based on an expected voltage value compared to the measured voltage measurement, selecting a shape based on the cost function, generating corrected coordinates of the points along the probe based on the shape and displaying a representation of the probe using the corrected coordinates.

Various examples of methods and systems are disclosed for correction of phase and amplitude errors that occur in transmission lines connecting transmitter/receiver devices to measurement fixtures. In one example, a method is described that includes using time domain processing to determine a phase shift from the measurement fixture that can occur between calibration measurements and measurements of the specimen under test. In another example, a method is described that includes frequency-domain processing of the signals to obtain both phase and amplitude corrections. Including these phase and amplitude corrections in the calibration procedure can reduce or minimize the errors induced in the measurements when the transmission line(s) experience either temperature changes or physical deflections, among other things.

In one aspect, an angle sensor includes a first Hall element disposed on a first axis, a second Hall element disposed on a second axis perpendicular to the first axis and a conduction path having a first portion extending parallel to the first axis and a second portion parallel to the second axis. The conduction path is configured to conduct a calibration current that generates a first magnetic flux density measured at the first Hall element and a second magnetic flux density measured at the second Hall element. The angle sensor also includes calibration circuitry configured to generate one or more compensation signals based on the first and second magnetic flux densities and to adjust an external magnetic flux density measured at the second Hall element due to an external magnetic field using the one or more compensation signals to reduce angle error of the angle sensor.

A magnetic field measurement apparatus including a magnetic sensor array having magnetic sensor cells capable of detecting magnetic fields in three axial directions arranged in three dimensions, each magnetic sensor cell including a plurality of magnetic sensors that each have a magnetoresistive element and a magnetic flux concentrator arranged at least at one of one end and another end of the magnetoresistive element; AD converters that respectively convert analog detection signals output by the magnetic sensors into digital measurement data; a magnetic field acquiring section that acquires the digital measurement data; a calibration computing section that calibrates the digital measurement data from the magnetic field acquiring section, using at least one of a main-axis sensitivity, cross-axis sensitivities, and an offset; and a gradient magnetic field computing section that calculates a gradient magnetic field using magnetic field measurement data resulting from the calibration of the digital measurement data.

A magnetic sensor device includes a composite chip component, and a sensor chip mounted on the composite chip component. The sensor chip includes a first magnetic sensor, a second magnetic sensor, and a third magnetic sensor that detect components of an external magnetic field that are in directions parallel to an X direction, parallel to a Y direction, and parallel to a Z direction, respectively. The composite chip component includes a first magnetic field generator, a second magnetic field generator, and a third magnetic field generator for generating additional magnetic field components that are in directions parallel to the X direction, parallel to the Y direction, and parallel to the Z direction, respectively.

Provided is a magnetic field measuring apparatus for: acquiring the measurement data measured by a magnetic sensor array that is configured by arraying the plurality of magnetic sensor cells to form a surface covering at least a part of a target object to be measured; performing signal separation on a magnetic field spatial distribution indicated by the measurement data based on a position and magnetic sensitivity of each magnetic sensor; generating a calibration magnetic field at a position on a straight line that can be drawn without crossing the plurality of magnetic sensor cells from the measurement space outside the measurement space; and calibrating a sensor error for the magnetic sensor based on a separation error in a case where signal separation has been performed on a spatial distribution of the calibration magnetic field.