An apparatus and method are provided for implementing feedback control of the electropermanent magnets and also collecting information about magnetic fields emanating from a volume of interest containing a living being

A wearable audio device that includes an electro-acoustic transducer for creating audio output and a magnetometer system comprising a magnetic field sensor with an output, a temperature sensor that is configured to determine an internal device temperature, a processor, and memory. The magnetometer system is configured to derive from the magnetic field sensor output a directional heading of the Earth's magnetic field. The magnetometer system is further configured to compensate the magnetic field sensor output, wherein the compensation is temperature dependent. The memory is configured to store temperature-dependent compensation information. The magnetometer system is further configured to use the temperature sensor output to retrieve compensation information from the memory in order to compensate the magnetic field sensor output at the current temperature.

A wearable audio device that includes an electro-acoustic transducer for creating audio output and a magnetometer system comprising a magnetic field sensor with an output, a temperature sensor that is configured to determine an internal device temperature, a processor, and memory. The magnetometer system is configured to derive from the magnetic field sensor output a directional heading of the Earth's magnetic field. The magnetometer system is further configured to compensate the magnetic field sensor output, wherein the compensation is temperature dependent. The memory is configured to store temperature-dependent compensation information. The magnetometer system is further configured to use the temperature sensor output to retrieve compensation information from the memory in order to compensate the magnetic field sensor output at the current temperature.

A device for locating studs on a surface such as a wall is disclosed. The device comprises a housing, a plurality of magnets disposed in the housing, a level placed between the plurality of magnets and line lasers in which one line laser is provided at one end of the housing and another line laser is provided at an opposite end of the housing. A flux density of the plurality of magnets is used to determine a location and a distance between the studs on the surface. The level is used to accurately determine the position of the studs. The line lasers are configured to emit laser beams at each side of the housing to label location of successive studs for remainder of the surface based on the distance calculated using the plurality of magnets and the level.

A sensor device comprises a magnet having a magnetization in a first direction. Furthermore, the sensor device comprises a differential magnetic field sensor arranged on the magnet and having a first sensor element and a second sensor element, wherein the sensor elements are spaced apart in a second direction perpendicular to the first direction. The first sensor element and the second sensor element are designed to detect a magnetic field component in a third direction perpendicular to the first direction and perpendicular to the second direction.

A device and a method for detecting a defect contour with omnidirectionally equal sensitivity based on magnetic excitation are provided. The device includes a magnetic sensor array arranged in a spatially uniform magnetic field and configured to collect a magnetic field signal, and a data analysis module configured to analyze the magnetic field signal, extract a distorted magnetic field signal, and obtain an image of the defect contour based on the distorted magnetic field signal.

A device and a method for detecting a defect contour with omnidirectionally equal sensitivity based on magnetic excitation are provided. The device includes a magnetic sensor array arranged in a spatially uniform magnetic field and configured to collect a magnetic field signal, and a data analysis module configured to analyze the magnetic field signal, extract a distorted magnetic field signal, and obtain an image of the defect contour based on the distorted magnetic field signal.

A magnetic sensor includes a base material, a plurality of magnets provided at predetermined spacing on the base material, and a plurality of magnetic detection parts respectively provided close to the plurality of magnets. Each of the plurality of magnetic detection parts outputs a signal in accordance with change in the magnetic field accompanying deformation of the base material.

A magnetic sensor includes a base material, a plurality of magnets provided at predetermined spacing on the base material, and a plurality of magnetic detection parts respectively provided close to the plurality of magnets. Each of the plurality of magnetic detection parts outputs a signal in accordance with change in the magnetic field accompanying deformation of the base material.

A method for scanning artificial structure, wherein a scanning artificial structure apparatus comprises four magnetic-field sensors, the four magnetic-field sensors are non-coplanar configured, the method comprises following steps of: moving the scanning artificial structure apparatus along a scanning path within a to-be-tested area, in the meantime, measuring magnetic field by the four magnetic-field sensors, and recording a position sequence when measuring magnetic field, wherein four magnetic-field measurement sequences are measured by the four magnetic-field sensors; and calculating a magnetic-field variation distribution from the four magnetic-field measurement sequences and the position sequence, wherein the magnetic-field variation distribution is corresponding to at least one artificial structure distribution.