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Author

John D. Begin

Bio: John D. Begin is an academic researcher. The author has contributed to research in topics: Signal & Piezoelectricity. The author has an hindex of 5, co-authored 5 publications receiving 146 citations.

Papers
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Patent
20 Jul 1992
TL;DR: In this article, a position detection probe has a magnetostrictive wire stretched between a head and a reflective foot end termination, and a magnet displaceable along the probe and using the sonic pulse propagation time from the magnet to the foot as a position detector, compensation for thermal expansion and thermal change of propagation velocity is made based on the property of the total propagation time along the wire length being a unique function of temperature.
Abstract: In a position detection probe having a magnetostrictive wire stretched between a head and a reflective foot end termination, and a magnet displaceable along the probe and using the sonic pulse propagation time from the magnet to the foot as a position detection parameter, compensation for thermal expansion and thermal change of propagation velocity is made based on the property of the total propagation time along the wire length being a unique function of temperature and calibrating the probe at different temperatures to yield either equations or look up tables of true positions as functions of the total propagation time and the position detection parameter. By mapping wire characteristics at a plurality of magnet positions and temperatures to construct look up tables, wire nonlinearities as well as thermal effects can be compensated for.

46 citations

Patent
18 Feb 1993
TL;DR: In this article, a position detection probe having a magnetostrictive wire stretched between a head and a reflective foot end termination, and a magnet displaceable along the probe and using the sonic pulse propagation time from the magnet to the foot-end termination as a position detector, is made by measuring the wire resistance and calculating a compensation from the resistance.
Abstract: In a position detection probe having a magnetostrictive wire stretched between a head and a reflective foot end termination, and a magnet displaceable along the probe and using the sonic pulse propagation time from the magnet to the foot end termination as a position detection parameter, compensation for thermal expansion and thermal change of propagation velocity is made by measuring the wire resistance and calculating a compensation from the resistance. The probe is excited by an electrical pulse having a known current. The voltage across the wire is measured at a time when the current has stabilized to a precise value, and resistance is determined from the current and voltage.

38 citations

Patent
19 Jun 1990
TL;DR: In this paper, a combined magnetostrictive linear displacement detector and a plural location temperature detector are used to produce a composite signal for transmission on a 2 wire transmission line, where the resistances of the temperature sensitive resistors as well as two reference resistors are measured in a predetermined sequence.
Abstract: The present invention is a combined magnetostrictive linear displacement detector and plural location temperature detector. The combined apparatus produces a composite signal for transmission on a 2 wire transmission line. The resistances of the temperature sensitive resistors as well as two reference resistors are measured in a predetermined sequence. The linear displacement is measured by the length of time required for a torsional strain to travel along the magnetostrictive wire to the position of the magnet. A pulse generator generates a predetermined number of pulses for each resistance measurement having pulse period corresponding to the measured resistance, with the minimum such pulse period preferably being greater than twice the maximum time required for a torsional strain to propagate the length of the magnetostrictive wire. An electrical signal is supplied to the transmission line when either said pulse generator generates a pulse or the induced electrical signal is detected. The time between the pairs of pulses indicates the linear displacement fixed by the magnet. The time between pulse pairs is a measure of one of the resistances. The combined apparatus of the present invention also periodically degausses the magneteostrictive wire at a time when no displacement measurement is taking place.

35 citations

Patent
28 Oct 1996
TL;DR: A magnetostrictive waveguide position measuring apparatus includes a waveguide extending between opposed anchored ends as mentioned in this paper, where a magnet is displaceable along the waveguide and generates torsional strain in response to an electrical excitation signal transmitted along the Waveguide.
Abstract: A magnetostrictive waveguide position measuring apparatus includes a waveguide extending between opposed anchored ends. A magnet is displaceable along the waveguide and generates torsional strain in the waveguide in response to an electrical excitation signal transmitted along the waveguide. A piezoelectric film element is coupled to the waveguide to sense the torsional strain signal on the waveguide. A signal processor determines the relative elapsed time between the excitation signal and the output signal of the piezoelectric film element to determine the position of the magnet along the waveguide. The piezoelectric film element is coupled to the waveguide along an axis transverse to the axis of stretch of the element. Alternately, a differential piezoelectric film element formed of two piezoelectric elements contacts a waveguide, with the two elements connected in differential parallel or series configuration and in or out of phase to double the output current or the output voltage. The output of the differential piezoelectric elements are connected to an amplifier in either charge or voltage mode for noise, EMI and transient signal suppression.

19 citations

Patent
10 May 2013
TL;DR: In this paper, a controller, a moisture detector, and a blower are used to automatically dry wet floors by directing moving air toward the first location in response to an operating signal from the controller, which outputs the operating signal to the blower based on the moisture detection signal.
Abstract: An apparatus for automatically drying wet floors includes a controller, a moisture detector that is operable to detect the presence of moisture at a first location and transmit a moisture detection signal to the controller in response to detecting the presence of moisture at the first location, and a blower. The blower is operative to turn on and off for drying the wet floors by directing moving air toward the first location in response to an operating signal from the controller. The controller outputs the operating signal to the blower based on the moisture detection signal.

8 citations


Cited by
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Patent
20 Jul 2000
TL;DR: In this paper, a system for determining the position of a medical device having a sensor comprises a plurality of field radiators wherein each field radiator has multiple radiators and each radiator element generates a magnetic field such that each magnetic field is distinct from one another due to the use of a different frequency through simultaneous energizing of the radiator elements.
Abstract: A system for determining the position of a medical device having a sensor comprises a plurality of field radiators wherein each field radiator has a plurality of radiator elements. Each radiator element generates a magnetic field such that each magnetic field is distinct from one another due to the use of a different frequency through simultaneous energizing of the radiator elements. A signal processor is operatively connected to the field radiators and the sensor of the medical device for receiving a sensing signal from the sensor indicative of the magnetic field sensed at the sensor. Alternative field radiator arrangements are also provided in conjunction with a novel algorithm utilizing a global convergent technique.

403 citations

Patent
02 Jun 2000
TL;DR: In this article, a position feedback system is used to determine the position of movable elements on a path and control the movable element on the path and the programmable controller using positional information from the sensors.
Abstract: The present invention is directed to a machine with a position feedback system and a method for use thereof. The machine includes at least one movable element mounted for movement on a path and at least one programmable controller. The machine further includes at least two absolute or magnetostrictive sensors or the machine includes an absolute sensor and a non-absolute sensor. The programmable controller uses positional information from the sensors to determine the position of the movable elements on the path and control the movable elements. The method includes determining a known position for the movable elements, linking at least two magnetostrictive sensors into one virtual sensor, and/or performing commutation alignment for the movable elements. Determining the position and commutation alignment can occur when the movable elements are stationary or moving.

379 citations

Patent
06 Jul 2001
TL;DR: In this paper, a system for detecting electrode-tissue contact comprises a catheter having a location sensor and a distal tip electrode, and a signal generator to transmit test signals to the distal and reference electrodes.
Abstract: A system for detecting electrode-tissue contact comprises a catheter having a location sensor and a distal tip electrode. The catheter preferably further comprises a reference electrode that is preferably protected from making contact with tissue. The system further comprises a signal generator to transmit test signals to the distal tip and reference electrodes. Tissue contact is detected by comparing the signals across the tip electrode to a return electrode versus the signal across the reference electrode to a return electrode. Ablation energy may be delivered to the distal tip electrode if contact of the electrode with tissue is detected.

232 citations

Patent
30 Jul 2004
TL;DR: In this article, a method for tracking an object includes producing energy fields at a plurality of different frequencies in a vicinity of the object, and receiving signals that are generated at a location of an object at the different frequency in response to the energy fields.
Abstract: A method for tracking an object includes producing energy fields at a plurality of different frequencies in a vicinity of the object, and receiving signals that are generated at a location of the object at the different frequencies in response to the energy fields. Multiple computations are made of spatial coordinates of the object based on the signals received at the different frequencies. Convergence of the computations is tested in order to ascertain whether the energy fields have been perturbed by an article in the vicinity of the object.

110 citations

Patent
29 Sep 1998
TL;DR: In this paper, a wire of predetermined length, tip, proximal end and markings at predefined intervals in a vessel, positioning the wire at the desired catheter tip location using an imaging method, such as fluoroscopy, and determining the catheter and tunnel lengths required based on the number of markings.
Abstract: Kits and methods of the invention provide for preinsertion measurement of a catheter and tunnel lengths required to position the tip of a catheter, such as a dialysis catheter, at a desired location within a body vessel or lumen, such as a vein. Kits of the invention include a wire of predetermined length which has a tip, a proximal end, and a plurality of markings at predefined intervals. The wire is inserted into a body vessel so that the tip of the wire is positioned at the desired catheter tip location. The number of markings on the portion of the wire remaining outside the body are then counted and used to calculate the length of wire either outside or inside the body. This length of wire may be found in a conversion chart, which is also included in the kit, and matched to a corresponding catheter and tunnel lengths or catheter code. Methods of the invention include inserting the wire having predetermined length, tip, proximal end and markings at predefined intervals in a vessel, positioning the wire at the desired catheter tip location using an imaging method, such as fluoroscopy, counting the number of markings remaining outside the body, and determining the catheter and tunnel lengths required based on the number of markings. The determination of the catheter and tunnel lengths required may also be performed using a conversion chart.

52 citations