G01R33/0035

MEASURING DEVICE COMPRISING A MAGNETIC FIELD GENERATOR AND ASSOCIATED MEASUREMENT METHOD
20210072184 · 2021-03-11 ·

The invention relates to a device for measuring a first parameter of a specimen, the device including a measuring volume configured to receive the specimen, a first control module and a measuring module, the first control module being configured to supply electricity to the measuring module with an electrical supply current, the measuring module including a magnetic field generator, a sensor and a second control module, the magnetic field generator being configured to generate a magnetic field in the measuring volume, the sensor being configured to measure values of a variable of the measuring volume during the generation of the magnetic field, the second measuring control module being configured to calculate a value of the parameter based on at least one value of the variable.

The first control module is configured in order, following the generation of the magnetic field, to inhibit the power supply of the measuring module during a first predetermined length of time (dn).

Calibrating a magnetic sensor

A calibration system comprising: a Helmholtz device comprising thee pairs of coils defining an inner volume, wherein each of the three pairs of coils is configured to generate a magnetic field that is uniform throughout the inner volume; a mount configured to accept a device that includes a magnetic sensor, wherein at least a portion of the mount is positioned within the inner volume such that the magnetic sensor is positioned at or near a center of the inner volume when the device is positioned on the mount; and a computer system configured to communicate with the Helmholtz device and the magnetic sensor, wherein the computer system is configured to: provide instructions to cause each of the three pairs of coils to generate a magnetic field; receive signals from the magnetic sensor that are based on characteristics of the magnetic fields received at the magnetic sensor; measure, based on the signals received from the magnetic sensor, one or more characteristics of the magnetic sensor; and determine, using a calibration algorithm, one or more calibration correction factors for the magnetic sensor based on the one or more characteristics of the magnetic sensor and the provided instructions.

Method and system for magnetometer calibration
10914793 · 2021-02-09 · ·

Systems and methods are disclosed for automatically calibrating a magnetometer during user activity. A portable device associated with a user provides magnetic field measurements during user activity, which are converted to a frequency domain and frequency component(s) that correspond to the user activity are distinguished. A criterion is defined for the distinguished frequency components such that magnetometer bias is estimated by satisfying a condition for the criterion. Accordingly, the estimated magnetometer bias may be applied to the obtained magnetic field measurements. The calibrated magnetic field measurements may be used for any suitable purposes, including for building a magnetic fingerprint map using crowdsourcing techniques.

Magnetic sensor systems

A calibration apparatus for calibrating a magnetic sensor configured to generate an output signal indicative of magnetic field strength when a bias signal is applied to it is disclosed. The apparatus includes a test magnetic field generator (MFG) to generate magnetic fields of known magnitude, and further includes a processor to control the MFG to generate a known magnetic field, control the sensor to generate a test output signal when the MFG generates the known magnetic field and a known bias signal is applied to the sensor, and determine how to change the bias signal based on a deviation of the measured test output signal from an expected output signal. Using a test MFG that produces known magnetic fields when known bias signals are applied to sensors allows evaluating and compensating for changes in sensitivity of the sensors by accordingly changing bias signals applied to the sensors.

Magnetic sensor sensitivity matching calibration

A magnetic sensor device comprises a substrate, first and second magnetic sensors, and one or more inductors are disposed over the substrate and are controlled by a magnetic sensor controller having a control circuit. The control circuit controls the first magnetic sensor to measure a first magnetic field and the second magnetic sensor to measure a second magnetic field under presence of a fifth magnetic field generated by the inductors. The control circuit controls the first magnetic sensor to measure a third magnetic field and the second magnetic sensor to measure a fourth magnetic field under presence of a sixth magnetic field generated by the inductors, the fifth magnetic field and the sixth magnetic field being different. The control circuit calculates a relative sensitivity matching value converting magnetic field values measured by the second magnetic sensor to a comparable magnetic field value measured by the first magnetic sensor.

IN-FIELD SOFT MAGNETIC DISTORTION HARDWARE COMPENSATION

A method for calibrating a magnetometer of an electronic device can include detecting a change in a magnetism of the electronic device, collecting a first magnetic field data from the magnetometer at sampling frequency of at least 1 hertz, generating an elliptical calibration model based at least partially on the collected first magnetic field data, collecting a second magnetic field data from the magnetometer, and fitting the collected second magnetic field data to a sphere using the elliptical calibration model.

METHOD FOR RECALIBRATING A MICROMECHANICAL SENSOR, AND RECALIBRATEABLE SENSOR

Recalibrating a micromechanical sensor. The sensor is assigned a signal processing device for correcting the sensor signal on the basis of at least one previously determined initial trim value that is selected such that, given a defined sensor excitation, a production-related deviation of the sensor signal from a target sensor signal is compensated. The method for recalibrating the sensor includes: applying a defined electrical test excitation signal to the sensor structure, acquiring the corresponding sensor response signal, ascertaining a trim correction value for the at least one initial trim value on the basis of a previously determined relation between the sensor response signal and the trim correction value, and determining at least one current trim value for correcting the sensor signal, the determination of the at least one current trim value taking place on the basis of the at least one initial trim value and the ascertained trim correction value.

Control device, multi-projection system and control method of control device
10911728 · 2021-02-02 · ·

A control device configured to communicate with a first projector which projects a first image in a first projection area, and a second projector which projects a second image in a second projection area having a first overlap area overlapping the first projection area to make the first projector and the second projector perform an edge blending process includes a reception section for receiving input of designation information including a direction in which an overlap width, a generation section for generating first overlap information including information representing first side in the first overlap area and information representing the overlap width of the first overlap area, and second overlap information including information representing second side in the first overlap area and the information, and a transmission section for transmitting the first overlap information to the first projector, and the second overlap information to the second projector.

Magnetic force sensor and production thereof

The invention relates to a magnetic force sensor (100), having at least one conducting track (111, 211) of soft magnetic material, wherein the at least one conducting track (111, 211) has at least one interruption (130) having a distance (A), wherein the force sensor (100) is arranged on a substrate, in particular on a component (1, 2) to be monitored, and a change in the distance (A) or rather a change in the magnetic flux in the at least one magnetic conducting track (111, 211) is monitored.

System for continuous calibration of hall sensors

A system comprises a calibration current generator, which provides a calibration current to a first and a second Hall channel, and a bias current generator, which determines a difference between a calibration signal from the Hall channels and a threshold and adjusts a biasing current for the Hall channels based on the difference. In some embodiments, the bias current generator comprises a subtractor coupled to an ADC and a controller coupled between the ADC and a DAC. The subtractor obtains a first and a second signal from the first and second Hall channels, respectively, and subtracts the first from the second to obtain the calibration signal. The controller determines the difference between a sampled signal from the ADC and the threshold and an adjustment to the biasing current based on the difference. The DAC adjusts the biasing current based on a control signal from the controller indicating the adjustment.