7654results about "Material magnetic variables" patented technology

A telemetry method and apparatus using pressure sensing elements remotely located from associated pick-up, and processing units for the sensing and monitoring of pressure within an environment. This includes remote pressure sensing apparatus incorporating a magnetically-driven resonator being hermetically-sealed within an encapsulating shell or diaphragm and associated new method of sensing pressure. The resonant structure of the magnetically-driven resonator is suitable for measuring quantities convertible to changes in mechanical stress or mass. The resonant structure can be integrated into pressure sensors, adsorbed mass sensors, strain sensors, and the like. The apparatus and method provide information by utilizing, or listening for, the residence frequency of the oscillating resonator. The resonant structure listening frequencies of greatest interest are those at the mechanical structure's fundamental or harmonic resonant frequency. The apparatus is operable within a wide range of environments for remote one-time, random, periodic, or continuous/on-going monitoring of a particular fluid environment. Applications include biomedical applications such as measuring intraocular pressure, blood pressure, and intracranial pressure sensing.

An electromagnetic imaging method for electromagnetically measuring physical parameters of a pipe CJ, CC by means of a plurality of measuring arrangement ZMA, MCMA, MonMa, ImMA comprising a plurality of transmitter coil ZTX, LFTX, DTX and a plurality of receiver coil ZRX1, ZR2, MRX, MC, PRX1, PRX2, PRX3, PRX4, PRX5, PRX6, PRX7, PRX8, PRX9, PRX10, PRX11, PRX12, PRX13, PRX14, PRX15, PRX16, PRX17, PRX18, the transmitter coils and receiver coils being associated so as to form the plurality of measuring arrangement, the plurality of measuring arrangement being adapted to be positioned into the pipe and displaced through the pipe, the physical parameters being measured for a plurality of position along the pipe, the method comprising the steps of:

• a) determining a first value of an average ratio of magnetic permeability to electrical conductivity and a first value of an average inner diameter of the pipe Z-MES,
• b) determining an average electromagnetic thickness of the pipe MC-MES,
• c) determining a second value of the average ratio of magnetic permeability to electrical conductivity and a second value of the average inner diameter of the pipe Mon-MES according to excitation frequencies which are substantially lower than the excitation frequencies used to determine the first values Z-MES,
• d) determining a first image EMTIM of the pipe electromagnetic thickness and the pipe defects Im-MES,
• e) discriminating the defects at an inside perimeter of the pipe from the defects at an outside perimeter of the pipe Dis-MES, and
• f) forming a corrected first image IOFIM of the pipe taking into account a position of the defects.

The present invention provides a long-range, untethered, live, in-pipe inspection system that includes a self-propelled train having a plurality of modules; joint members for interconnecting adjacent modules, data collection components, and wireless communication components for transmitting collected data and receiving control messages. The module-train includes, generally, at least one, and preferably two drive modules, at least one power module and an electronics module. The train may additionally include at least one support module, which may be interposed between the power and electronics modules. In one embodiment of the invention, there are two drive modules, one at each terminal end of the train, two power modules, one adjacent to each drive module, two support modules, one adjacent to each power module, and one central electronics and computing module.

Apparatus for detecting a metal object comprises a transmitter for generating a pulsed or an alternating magnetic field in the vicinity of the metal object to be detected and a detector for detecting the secondary magnetic field induced in the metal object by the transmitted magnetic field. The detector measures at least three magnetic field gradient components of at least first order of the secondary magnetic field. The apparatus also comprises a processor for determining at least one of the position or the electro-magnetic cross-section or an estimate of the shape of the metal object from the measured magnetic field spatial gradient components. The processor fits the measured components to dipole, multiple dipole, multipole, or extended source models. In a preferred embodiment, the invention may comprise three or more pairs of gradiometric coils, or other sensing means. The detector measures at least five magnetic field gradient components of at least first order, and one or more components of the secondary magnetic field. The detector may be coils, or any other magnetic sensors. The processor enters pre-determined criteria to discriminate against detection of metal objects of no interest or to selectively detect metal objects of interest.

A Hall sensor array for offset-compensated magnetic field measurement comprises a first and at least one additional pair of Hall sensor elements. Each Hall sensor element has four terminals, of which two act as power supply terminals for supplying an operating current and two act as measurement terminals for measuring a Hall voltage. Respective first supply terminals of each Hall sensor element are connected together and to a first terminal of a common voltage source and respective second supply terminals of each Hall sensor element are connected together and to a second terminal of the common voltage source so that the common voltage source supplies an operating current for the Hall sensor elements. The Hall sensor elements are operated in the spinning current mode so that the offset voltages of the Hall sensor elements approximately cancel one another out in a revolution so that the Hall signal contributions which actually depend on the magnetic field remain.

A device for measuring a motion of a moving electrically conducting body is disclosed. A magnetic field generated by, for example, electromagnets or permanent magnets, penetrates at least a partial area of the moving body. Two or more measuring devices are arranged outside the magnetic field to measure a measurement magnetic field that is induced by electrical currents in the moving body. The measuring devices are arranged essentially symmetrically with respect to the magnetic field generating means or the moving body. The measurement magnetic field represents at least one motion variable of the moving body. The measuring device is thereby no longer subjected to the temperature-dependent variations of the exciting field.

Techniques for ultrahigh density writing on an erasable magnetic medium include using a micromachined mechanism having two probes for writing to the medium. Use of the two probe embodiment eliminates the need to change the magnetic orientation of the probe. In another embodiment, a single probe is provided which is heated to the vicinity of its Curie temperature to enable the magnetic orientation of the probe to be switched. The probe may be heated to its Curie temperature through the use of a heating element or a focused laser. In another embodiment of the present invention, either the magnetic orientation of the probe or the magnetic orientation of the medium may be switched through the combination of a static magnetic field, a radio frequency magnetic field and, under certain circumstances, the magnetic field of the probe. In all cases, the writing techniques enable information to be written to a magnetic medium in a manner which enables the information to be erased and the medium rewritten.

A pocket-sized object finder has a compact housing containing a battery, circuitry and a capacitor plate for detecting an object hidden behind a wall. The battery powered circuitry includes multiple signal indicators that illuminate in a serial manner when the object is being detected. The signal indicators are successively tapered and are mounted at a front side of a tapered end of the housing. The capacitor plate is disposed in the housing along its rear wall and is responsive to variations in capacitance that occur as the object finder is brought near and over the object. The compact housing defines a cavity with a width that is no more than two inches and one third its length. A removable access door, with a pocket clip, at an end opposite the signal indicators allows access to the battery within the housing cavity.

An apparatus and method are disclosed for detecting flaws in electrically conductive materials by observing properties of the back-EMF of the eddy current field generated by driving magnetic flux through the object to be examined. The input signal may include sweeps at several frequencies, and may do so at one time under the principle of wave superposition. The sectorial observations of eddy currents summations may be compared to a known datum for a defect free material, the presence of anomalies in eddy field back EMF divergence tending to provide an indication of an irregularity in the underlying eddy field, and hence in the underlying material itself. The portable unit may have a number of different configurations depending on the nature of the object to be examined, be it a flat or large radius plate, a flange, a rail, or some other structural element.

A method and apparatus for obtaining a resistivity measurement of an earth formation surrounding a borehole in an MWD device uses an electrode for injecting current into the earth formation and an electrode for obtaining a responsive signal from the borehole. The electrodes are located on the drill bit arm or blade. Measured resistivity values are obtained at the location of the drill bit. Measurements can be taken in both oil-based mud and water-based mud environments. Maximum or minimum resistivity can be used to best represent the resistivity of the surrounding formation.

An apparatus adapted to interact with a cylindrical mold for a gyratory compactor so as to determine a property of the gyratory compactor is provided, wherein the mold is adapted to contain a sample therein. Such an apparatus comprises a rigid disk-shaped plate defining an axis and a periphery, with the plate being adapted to be disposed within the mold. At least one sensing device is operably engaged with the plate, wherein the at least one sensing device is configured to measure a proximity of the at least one sensing device with respect to a reference member and to produce a corresponding signal indicative of the property of the gyratory compactor. In one embodiment, the apparatus is configured to determine the gyration angle of the mold, while in another embodiment, the apparatus is configured to determine the pressure exerted on the sample within the mold. The property of the mold may be determined either statically or dynamically. Associated apparatuses, devices, systems, and methods are also provided.

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. The transmitter apparatus employs an FET-driven capacitive tuning circuit and a coil design that achieves high precision, high-quality transmission signals, and which is equipped with a high-voltage booster for facilitating fault-localization applications.

An instrument pig and method of operation thereof for determining the characteristics of a ferromagnetic pipeline through which it passes, including a pig body, first and second coaxial circumferential, spaced apart magnets of opposed polarities supported to the pig body and providing substantially complete magnetic saturation of an area of the pipeline between the magnets, first instruments between the magnets and arranged to generate signals that are responsive to flux leakage servicing to provide first information as to anomalies in the pipeline interior and/or exterior surfaces, second instruments supported by the pig body between said magnets and arranged to generate signals that are responsive to eddy currents induced in the pipeline interior surface servicing to provide second information as to anomalies in the pipeline interior surface, signal processing circuitry combining the first and second signals and wherein the second instruments are energized only in response to signals generated by said signal processing circuitry.

The invention discloses an additive manufacturing surface defect, internal defect and shape composite detection device which comprises a surface defect detection system, an internal defect detection system, a shape three-dimensional measurement system and a clamping device, wherein the surface defect detection system comprises a first CMOS industrial camera; the internal defect detection system comprises an air cylinder and a detection probe; the detection probe is used for generating a magnetic field to be close to the detected surface and establish magnetic mutual action with a workpiece to form a magnetic disturbance environment; the shape three-dimensional measurement system comprises a line laser, a light filter and a second CMOS industrial camera. The device can perform real-time and comprehensive detection on the surface defect, the internal defect and the shape three-dimensional size in additive manufacturing, transmits data to an industrial personal computer for analysis, interacts with forming milling composite route planning software, and can control a shaping device in real time to perform formation and generate a milling code and control a milling cutter to perform milling on the additive manufacturing surface.

Sensor assay methods for detecting the presence of an analyte in a sample are provided. Aspects of the methods include providing a sensor, e.g., a proximity sensor, in contact with an assay composition that includes a sample and a proximity label. Next, a capture probe configured to bind to the proximity label and the analyte is introduced into the assay composition to produce a labeled analyte. Following capture probe introduction, a signal is obtained from the sensor to detect the presence of the labeled analyte in the sample. Also provided are sensor devices, including hand-held devices, and kits that find use in practicing the subject methods.

Systems and methods for optically determining casing collar and/or corrosion locations within boreholes, using the diffraction effect of Faraday crystals through which depolarized continuous light is transmitted within optical fibers.