4045results about "Magnetic property measurements" patented technology

A pipeline inspection and defect mapping system includes a pig having an inertial measurement unit and a pipeline inspection unit for recording pig location and defect detection events, each record time-stamped by a highly precise onboard clock. The system also includes several magloggers at precisely known locations along the pipeline, each containing a fluxgate magnetometer for detecting the passage of the pig along the pipeline and further containing a highly precise clock synchronized with the clock in the pig. The locations of the various magloggers are known in a north/east/down coordinate system through a differential global positioning satellite process. Finally, a postprocessing off-line computer system receives downloaded maglogger, inertial measurement, and odometer data and through the use of several Kalman filters, derives the location of the detected defects in the north/east/down coordinate frame. Consequently, a task of identifying sites for repair activity is much simplified.

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.

Ultrasonic waveguides having improved velocity gain are disclosed for use in ultrasonic medical devices. Specifically, the ultrasonic waveguides comprises a first material having a higher acoustic impedance and a second material having a lower acoustic impedance.

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.

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 method and system for testing a read transducer are described. The read transducer includes a read sensor fabricated on a wafer. A system includes a test structure that resides on the wafer. The test structure includes a test device and a heater. The test device corresponds to the read sensor. The heater is in proximity to the test device and is configured to heat the test device substantially without heating the read sensor. Thus, the test structure allows for on-wafer testing of the test device at a plurality of temperatures above an ambient temperature.

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 a method is provided based on the Magnetic Resonance techniques to analyze and measure a uni- and/or a bi-directional flow regime of multiphase fluids in a transport and production conduct, in real time and flow-rates, based on a magnetic resonance analytical module, two magnetic prepolarization modules of variable effective length and a control computer of data acquisition and transfer, all associated to each other.

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 are disclosed which are operable to determine a capacitance associated with at least one piezoelectric element in an dual actuator disk drive. The capacitance information is used to adjust a driver used to drive the piezoelectric element. Capacitance is determined by supplying a predetermined current into the piezoelectric element(s) for a predetermined time period. A voltage associated with the piezoelectric element(s) is measured following the predetermined time period. The capacitance of the piezoelectric element(s) is then calculated based on the measured voltage, the current supplied, and the predetermined time period.

Method and implementing apparatus useful in acquiring data on acoustic features within a sample provides a pulsed acoustic probe and a stage system for effecting relative movement between the sample and the probe. The stage system is commanded such that the probe interrogates a non-rectangularly bounded space on the sample surface or within the volume of the sample. Acoustic energy reflected from or transmitted through the sample is sensed. Amplitude signals are developed from the sensed acoustic energy. Data characterizing the developed amplitude signals are stored for subsequent processing.

An ultrasonic probe includes a light irradiating portion configured to radiate light for generating ultrasonic waves from a light absorber, an ultrasonic transducing portion configured to transduce the ultrasonic waves to an electric signal, and a light guide member configured to introduce light from a light source to the light irradiating portion. A light irradiating region of the light irradiating portion is included within an ultrasonic receiving region of the ultrasonic transducing portion.

A method of connecting a plurality of probe pins to a plurality of first external connection pads, which are provided on a head gimbal assembly and are electrically connected to a plurality of terminal electrodes of a write magnetic head element, respectively, and a plurality of second external connection pads, which are provided on the head gimbal assembly and are electrically connected to a plurality of terminal electrodes of a read magnetic head element. In the connection method, an approach direction of the probe pins to the first external connection pads and an approach direction of the probe pins to the second external connection pads are made different from each other.

Provided is an electromagnetic tracking system, including at least one electromagnetic field receiver having at least one scalar-magnetometer, at least one electromagnetic field transmitter, and tracker electronics. Also provided is a method for electromagnetic tracking, including generating at least one magnetic field, sensing the at least one magnetic field with at least one scalar-magnetometer, and determining a relative position of the at least one scalar-magnetometer based on the sensed at least one magnetic field.

The present disclosure provides a method of monitoring a property of a sample, such as a nanoscopic property of the sample. The method comprises the steps of providing a quantum probe having a quantum state and exposing the quantum probe to the sample in a manner such that the property of the sample, in the proximity of the quantum probe, affects quantum coherence of the quantum probe. The method also comprises detecting a rate of quantum decoherence of the quantum probe to monitor the property of the sample. Further the present disclosure provides an apparatus for monitoring a property of a sample.

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.

Method and apparatus for ultrasonic inspection of an object. A tire is mounted for rolling along the surface of the object. It contains a liquid and a transducer assembly. The transducer assembly is positioned in the tire adjacent a portion of the surface of the tire in contact with the object. The liquid and the surface of the tire in contact with the object provide an acoustic bridge between the transducer assembly and the object. An electric signal processing system is connected to the transducer assembly. It generates electric signals which are converted to acoustic signals in the transducer assembly to place acoustic signals in the object. Acoustic signals returned from the object are converted to electric signals by the transducer assembly, and are processed in the electric signal processing system to indicate flaws in the object.