Abstract: A method of geophysical prospecting for detecting bodies of fluids in underground formations comprises the steps of activating a seismic energy source (2) to transmit seismic energy into the ground, detecting an electromagnetic signal (14) generated by interaction between the seismic energy and underground formations (12) including fluids, and recording properties of the detected electromagnetic signal against time, so as to record an electromagnetic signal generated by interaction between a secondary energy impulse (10) from the activation of the energy source and underground formations including fluids. The secondary energy impulse propagates to the formations more slowly than the primary seismic waves from the same activation of the energy source travelling at the speed of sound as attenuated by the materials through which they pass. The detected electromagnetic signal comprises frequencies in the range 0 to 30 Hz.

Abstract: A method of eddy current testing for flaws in a tube is provided that includes passing an eddy current probe through the tube and obtaining eddy current data for a number of positions along the tube, analyzing the eddy current data to generate background noise data for a number of positions along the tube, analyzing the eddy current data to generate extracted data for a number of positions along the tube, and determining whether a flaw of a particular category is present in the tube based on a set of one or more of rules applied to at least a portion of the extracted data, wherein at least one of the rules uses a particular part of the extracted data and employs a threshold that is a function a particular part of the background noise data that is associated with the particular part of the extracted data.

Abstract: The present invention is a metallic sensing ground probe comprising a rod and a handle having a port for storing a power supply in electrical communication with a circuit, for generating an electric field between a sensor tip on a distal end of the rod and a logic circuit for actuating an LED in an LED display unit on the handle, when the sensor tip encounters a metal object within the ground thus completing the circuit.

Abstract: The present disclosure describes various geophysical survey systems and methods for mapping an electric potential field. At least one illustrative embodiment includes an electromagnetic (EM) source and geophysical survey cables that each includes multiple electrodes spaced apart along each geophysical survey cable's length, and multiple data acquisition units that each obtains measurements indicative of an electric potential between two the electrodes. A calculation module is included and configured to combine signals representative of the measurements to produce signals indicative of the electric potential of each electrode relative to a reference potential assumed to be present at a selected electrode for each of the plurality of geophysical survey cables. Each reference potential is assumed to be of a magnitude that is within a tolerance range of a common reference potential.

Abstract: An integrated magnetic sensor formed in a body including a substrate of semiconductor material, which integrates a Hall cell. A trench is formed in the body, for example, on the back of the substrate, and is delimited by lateral surface portions that extend in a direction transverse to the main face of the body. The trench has a depth in a direction perpendicular to the main face that is much greater than its width in a direction parallel to the main face of the body, between the lateral surface portions. A concentrator made of ferromagnetic material is formed within the trench and is constituted by two ferromagnetic regions, which are set at a distance apart from one another and extend along the lateral surface portions of the trench towards the first Hall cell.

Abstract: A real-time calibration system and method for a mobile device having an onboard magnetometer uses an estimator to estimate magnetometer calibration parameters and a magnetic field external to the mobile device (e.g., the earth magnetic field). The calibration parameters can be used to calibrate uncalibrated magnetometer readings output from the onboard magnetometer. The external magnetic field can be modeled as a weighted combination of a past estimate of the external magnetic field and the asymptotic mean of that magnetic field, perturbed by a random noise (e.g., Gaussian random noise). The weight can be adjusted based on a measure of the statistical uncertainty of the estimated calibration parameters and the estimated external magnetic field. The asymptotic mean of the external magnetic field can be modeled as a time average of the estimated external magnetic field. are within the scope of the following claims.

Abstract: A patient positioning couch for a combined medical examination device is disclosed. In at least one embodiment, at least one opening is provided in a support plate of the patient positioning couch and the patient positioning couch includes at least one conveyor belt in order to move a patient on the support plate in the longitudinal direction.

Abstract: A high-Q human-portable, battery-powered self-correcting tunable resonator in a transmitter apparatus for inducing alternating currents of high quality in buried conductors to facilitate their location is disclosed. The transmitter apparatus may employ an FET-driven capacitive tuning circuit and a coil design that achieves high precision, high-quality transmission signals, and which may be equipped with a high-voltage booster for facilitating fault-localization applications.

Abstract: A system senses the position of a movable element in a mechanical apparatus. The element moves along an elongated guide member, which is at least partially formed of a magnetic material. An excitation coil is positioned by the guide member and a sensing coil moves with the movable element. An excitation circuit energizes the excitation coil and a position sensing circuit sense a voltage or current in the sensing coil to determine the distance between the coils.

Abstract: Embodiments of the invention described herein provide a magnetic sensor interface capable of adjusting signal conditioning dynamically such that the true positive and negative peaks of the input signal are maintained for a given target across its entire speed range (0-Max rpm), therefore increasing the signal to noise ratio at low speeds and avoiding clipping or distortion at high speeds. In one aspect, a method comprises receiving an alternating differential voltage signal from a sensor. The alternating differential voltage signal has an amplitude that changes over time. The alternating differential voltage signal is converted to an attenuated single-ended voltage signal that can be dynamically scaled. The attenuated single-ended voltage signal can be scaled by multiplying the attenuated single-ended voltage signal by a scaling factor. The scaling factor is selected relative to a signal-to-noise ratio of the scaled attenuated single-ended voltage signal.

Abstract: A shielded eddy current coil probe is formed on a printed circuit board and comprises a first coil component forming a test coil and a second coil component forming an active shielding coil. The test coil and the active shielding coil are concentrically arranged and the number of coil windings in the active shielding coil and the field direction thereof are configured to limit the induced field or the sensed field in the test object to the footprint area of the test coil on the test object. Multiple sets of test coils with active shielding coils can be provided on the same or different layers of the printed circuit board to realize different driver, receiver and combined driver/receiver coil configurations.

Abstract: Methods for testing for defects on magnetic media storage disks are provided. One such method includes dividing a surface of a magnetic media disk into a plurality of radial zones, dividing the disk surface into a plurality of concentric zones, thereby forming a preselected number (N) of wedge subsections for each of the concentric zones, scanning the disk surface for defects, counting the defects contained within each of the wedge subsections, summing the defects contained within two or more of the wedge subsections, comparing the summed defects with a preselected threshold, and determining, based on the comparison, a defect type of the disk.

Abstract: Axis axial position measurement system uses the electric signal generated by one or more sensors at the passage of teeth of a cogwheel fixed on the axis. The cogwheel is cut with at least one group of teeth, including at least three types of teeth of different height: a first type of teeth (1) of constant maximum height, a second type of teeth (2) of constant minimum height, and a third type of teeth (3) of variable height in the axial direction of the axis between the maximum and minimum heights of the teeth of the first and second type of teeth.

Abstract: A method for estimating the magnetization level of one or more permanent magnets established in one or more permanent magnet rotors of a wind turbine generator includes the steps of: establishing one or more magnetization sensors at the stator of the generator, connecting the one or more magnetization sensors to a measuring mechanism, processing measured data in the measuring mechanism, and establishing values of magnetization. Furthermore the invention also relates to a wind turbine.

Abstract: The instant invention senses shutter blade position indirectly by sensing the position of rotor(s) driving the shutter blade in an electromagnetically driven actuator system. It generally comprehends systems where a plurality of rotors each drive respective blades of a shutter such that the position of each of the rotors is indicative of the position of their respective shutter blades, and combines such systems with non-optical sensors responsive to the rotors which signal the position of the shutter blades based on the position of the rotors. The non-optical sensors used are preferably responsive to the magnetic fields produced by the rotors, and can be advantageously positioned adjacent stator poles associated with the rotors, which stator poles are associated with the open or closed positions of the shutter blades. The sensors are preferably Hall Effect (Hall IC) sensors producing voltages proportionate to and greatest when the pole of a magnet is proximate the Hall Effect sensor.

Abstract: A device rotates at least one static magnetic field about an axis, producing a rotating magnetic dipole field, and is movable in relation to the surface of the ground. The field is periodically sensed using a receiver to produce a receiver output responsive to the field. A positional relationship between the receiver and the device is monitored using the output. In one aspect, changing the positional relationship, by moving the device nearer to a boring tool which supports the receiver, causes an increase in accuracy of depth determination. In another aspect, determination of an actual overhead position of the boring tool, and its application, are described. Use of a plurality of measurements over at least one-half revolution of each magnet is disclosed. Establishing a surface radial direction toward a boring tool and resolution of multi-valued parameters is described. Calibration techniques, as well as a three transmitter configuration are also described.

Abstract: A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.

Abstract: A magnetoresistive angular sensing method is disclosed. In a first mode, a first dc external magnetic field in a predetermined direction is applied to an angular sensor arrangement in which the external magnetic field dominates over a magnetic field generated by an input device an angular position of which is to be sensed. In a second mode, a second external magnetic field is applied to the angular sensor. Outputs of the angular sensor arrangement in the two modes are processed to determine an angular orientation of the input device with offset voltage compensation.

Abstract: A resolver apparatus can include a resolver driven gear, a resolver stator, a resolver rotor coupled to the resolver stator and a resolver rotor drive shaft coupled to the resolver rotor, wherein the resolver rotor drive shaft is spring loaded to the resolver driven gear.

Abstract: The present invention concerns a scanner system for scanning the surface of an object, especially a vehicle wheel, the system comprises a mobile scanner including at least one sensor adapted to sense at least one position on the surface of the object and a reference system to which the sensor is sensitively adapted to provide at least one sensor signal corresponding the at least one sensed position on the surface with respect to the reference system, wherein the reference system is designed to provide a magnetic field having at least one orientation and the sensor is a magnetic sensor to be positioned within said magnetic field in proximity of or on the surface to be scanned.