Showing papers on "Inductive sensor published in 2007"

Using ambient light sensor to augment proximity sensor output

Abstract: Apparatuses and methods to sense proximity of an object and operate a proximity sensor of a portable device. In some embodiments, a method includes receiving an ambient light sensor (ALS) output, and altering, based on the ALS output, an effect of a proximity sensor output on control of a proximity determination. The ALS sensor and the proximity sensor may be located adjacent to an earpiece of a portable device. In some cases, the proximity determination may be a proximity of an object to the proximity sensor, and altering the effect may include changing the proximity of the object from a proximity greater than a first threshold to a proximity less than the first threshold. Other apparatuses and methods and data processing systems and machine readable media are also described.

Fiber-Optic Current Sensor for Electrowinning of Metals

Abstract: A highly accurate fiber-optic current sensor for direct currents up to 500 kA is presented. Applications include the control of the electrolysis process for the production of metals such as aluminum, copper, zinc, magnesium, and others. The sensor offers significant advantages with regard to performance and ease of use compared to state-of-the-art Hall-effect-based current transducers. The sensor makes use of the Faraday effect in an optical fiber loop around the current-carrying bus bars. A novel scheme of a polarization-rotated reflection interferometer and fiber gyroscope technology is used to measure the magneto-optic phase shifts. An appropriate technique has been developed for packaging the sensing fiber in a flexible strip of fiber-reinforced epoxy for loop diameters of up to several meters. Sensor accuracy and repeatability are well within 0.1% over a wide range of currents and temperatures. The sensor calibration is valid, regardless of the given magnetic field distribution, and remains stable under repeated manipulation of the flexible sensing strip.

New Noncontacting Inductive Analog Proximity and Inductive Linear Displacement Sensors for Industrial Automation

Abstract: Noncontacting inductive sensors are applicable on a large scale for position detection or travel measurement in industrial applications. Reasons for such broad acceptance in many sectors of industry are noncontact and wear-free sensing of the target (any metal object), reliability and robustness, resistance to fouling, water tightness and compact size. The present work is intended to be a systematic, complete, and consistent presentation of the technological innovations, recent implementations and current trends regarding the analog distance and travel sensing offered by noncontacting inductive sensors for industrial applications. It starts with the fundamentals of inductive sensing and presents the physical basics gained by modern analytic and simulation methods, as well as high-level integrated circuits for inductive sensors. The following sections deal with present-day inductive analog proximity sensors and with the distinctive technological innovation offered by the new inductive linear displacement sensors and with miniaturization results achieved through consistent integration.

Surface Sensor Network Using Inductive Signal Transmission Layer

Abstract: In this paper, we report the latest results of our two-dimensional communication project. In the system we show here, the sensor node that touches the surface of a two-dimensional signal transmission sheet (2DST sheet) establishes the connection. The system allows free location of the sensor node, and proximity (non-contact) connection is realized stably. The structure of 2DST sheet is simple and realized with various materials at low cost. Since the sensor nodes communicate with electromagnetic waves confined in two-dimensional medium, they are free from the interference from the nodes apart from the sheet. Powering with microwave through the sheet is also possible.

Systems and methods for remote sensing using inductively coupled transducers

Abstract: A remote sensing device includes a sensor and reference circuit. A resonant circuit of the sensor has a resonant characteristic modifiable by exposure to an external condition. The sensor is configured to produce a sensor signal associated with the modifiable resonant characteristic. A reference circuit of the remote sensing device is configured to produce a reference signal suitable for use in conjunction with the sensor signal. The reference signal is used to account for variations of the sensor signal due to variations in the inductive coupling between the remote sensing device and a reader designed to detect the reference signal and the sensor signal.

Flexible inductive sensor

Abstract: An inductive sensor includes an inductor comprising conductive loops and at least one hinge mechanically coupling the loops. Operation of the hinge changes the position of the loops and causes a change in the inductance of the sensor. A sensor material may be oriented with respect to the loops so that a dimensional change of the sensor material operates the hinge and causes the change in the position of the loops.

Apparatus and methods for proximity sensing circuitry

Abstract: An inductive proximity sensor is disclosed. The proximity sensor includes a resonator with a bifurcated inductance coupled to a plurality of transimpedance amplifiers. A portion of the resonator is configured to generate eddy currents in a target containing metal. In various embodiments, the transimpedance amplifiers provide signals associated with eddy currents to a synchronous detector. Apparatus and methods for operating the inductive proximity sensor are disclosed.

Sensor element and detection method of magnetic particles using this element, and detection method of target substance

Abstract: A sensor device is configured by using a sensor element including functions as a magnetic field sensor and capable of generating the magnetic field for collecting magnetic particles on a sensor surface by the application of the current. As a result, a sensor device can be provided in which the magnetic particles serving as a label can be effectively collected on the sensor, and at the same time, the influence given to the sensor by the magnetic field for collecting the magnetic particles can be reduced.

Monitoring system having implantable inductive sensor

Abstract: A system for monitoring physical properties of structures within animate and inanimate objects, including internal organs and bones of humans. The system includes sensing and readout devices. The sensing device is adapted to be implanted in a body and attached to a structure within the body, and includes an electrical circuit containing a first inductor coil formed at least in part by a conductor with portions thereof separated by gaps. The first inductor coil is adapted to be physically coupled to the structure so that changes in shape and size of the structure cause changes in shape and/or size of the first inductor coil and/or changes in the gaps, which alter the inductance of the first inductor coil when current flows through the electrical circuit. The readout device is not adapted to be implanted in the patient, and includes an inductor coil capable of electromagnetic telecommunication and/or electromagnetic powering of the sensing device.

Wireless Sensing System Using Open-Circuit, Electrically-Conductive Spiral-Trace Sensor

Abstract: A wireless sensing system includes a sensor made from an electrical conductor shaped to form an open-circuit, electrically-conductive spiral trace having inductance and capacitance. In the presence of a time-varying magnetic field, the sensor resonates to generate a harmonic response having a frequency, amplitude and bandwidth. A magnetic field response recorder wirelessly transmits the time-varying magnetic field to the sensor and wirelessly detects the sensor's response frequency, amplitude and bandwidth.

Apparatus and method for non-symmetric magnetic field balancing in an inspection scanner

Abstract: An inspection system positions a balancing shim to asymmetrically balance a magnetic field generated by an inductive sensor, which forms part of the inspection system. Additionally, relays and capacitors used to tune the inductive sensor to a desired resonance frequency are geometrically arranged to minimize electrical interference generated by operation of the relays and capacitors. A shielding device, which may be formed on a printed circuit board, protects a magnetic field generated by the inductive sensor from external electromagnetic interference. A slot positioned in the inductive sensor may be used to tune a resonant mode of the inductive sensor to accurately and particularly detect metallic shanks and/or other metallic objects in shoes, socks, and/or clothing.

Navigation arrangement for an electronic device

Abstract: A navigation arrangement for an electronic device that includes a screen, comprises: (i) a substantially transparent two dimensional capacitive position sensor that can be located over a screen of the device, and which can detect the position of an object with respect to the screen, and (ii) a two dimensional inductive position sensor for detecting the position of an intermediate coupler for example in the form of a pen or stylus with respect to the screen. The inductive position sensor comprises a transmit aerial for transmitting a signal, and a receive aerial for receiving the signal via the intermediate coupler so that the position of the intermediate coupler can be determined- The wiring of the inductive position sensor may be formed from a transparent conductor, or it may be arranged around the edge of the screen or behind the screen to enable the user to view the screen. Further forms of inductive position sensor, with or without capacitive position sensors, can enable a user to view a screen, for example by placing the inductive sensor tracks around the screen, or by connecting transparent conductors in parallel using low resistance busbars at the edge of the screen. Inductive position sensors may also be arranged to determine the position of the intermediate coupler in three directions, optionally in combination with other forms of sensor, and also to determine its orientation.

Active sensor with operating mode changeover

Abstract: Active sensor (1) for changing over to a special operating mode, wherein the sensor (1) has at least one sensor element (2), an evaluation circuit (3) and two connecting lines (4, 5) with a respective connection (41, 51) for transmitting the sensor-related information, wherein the supply voltage of the sensor (1) is present on these two connecting lines, wherein the sensor (1) comprises a changeover module (6), which can be used to change over between a normal operating mode and a special operating mode by the reversal of the polarity of the supply voltage present at the two connections. The invention furthermore relates to a method for driving an active sensor and to the use of the sensor (1), in particular as wheel rotational speed sensor, in motor vehicles.

A non-contact proximity sensor with low frequency electromagnetic field

Abstract: In this paper, a non-contact proximity sensor that is able to detect any kind of material with low frequency electromagnetic field is proposed. The sensor is simple and based on a single probe. In addition, it has two unique features which are flexibility of the probe and sensitivity to object thickness. After the theoretical analysis of the operation principle, experiments are given to analyze the validity of the theory and verify the ability of the sensor to detect object's proximity and thickness. Another experiment is also performed to examine the possibility of the sensor to detect the motion of the human heart. The sensor may potentially be applied in non-contact cardiac disease detection, micro-electromechanical systems (MEMS), cheap safe-guard system with one single sensor, thickness monitoring in standardization manufacturing, sport monitoring, and a lot of other places, etc.

Proximity and contact sensor and sensor element

Abstract: A proximity and contact sensor (10) is provided with a sensor element (11) and a detection circuit (16). The sensor element is provided with a matrix (13) in which coil-shaped carbon fibers (12) are dispersed. A high-frequency oscillation circuit (19) of the detection circuit (16) supplies the sensor element with a high-frequency signal. A detector (22) in the detection circuit (16) receives an output signal from the sensor element (11) and detects proximity of an object (24). In one example, the coil-shaped carbon fibers (12) are contained in the matrix by 1 to 20% by weight. In another example, a high-frequency oscillation circuit generates a high-frequency signal of 100 to 800 kHz.

Inductive sensor for sensing of two coupling elements

Abstract: In an inductive sensor device, and a method for inductive identification, a first and a second exciter inductor 16 a, 16 b extend along a measurement range and vary spatially differently from each other. A first and a second inductive coupling element 12 a , 12 b couple a signal from the exciter inductors 16 a , 16 b into a receiver inductor 18 . The inductive coupling elements 12 a , 12 b are formed as resonance elements with a first resonance frequency f 1 and a second resonance frequency f 2 . In order to be able to simply determine the position of both inductive coupling elements quickly and accurately, the two exciter inductors are driven by different transmission signals S 1 , S 2 . Each of the transmission signals includes signal components of a first carrier frequency near the first resonance frequency f 1 varying in temporal progression, and of a second carrier frequency near the second resonance frequency f 2 varying in temporal progression.

Inductive ultra-wide band detection and location of partial discharges in high-voltage cables

Abstract: In medium- and high-voltage cables with a helical structure of the earth screen current pulses from partial discharges travelling along the cable are observed to follow the spiralling structure. The resulting tangential current produces an axial magnetic field which can be detected by an inductive sensor without having to make any change to the cable. A specially developed inductive sensor placed around the outer sheath of an intact cable is made selectively sensitive to the high-frequency signals (± 100 MHz) arising from the partial discharges. The discharge pulses are recorded by a fast digitizer (bandwidth of 600 MHz). In laboratory experiments partial discharges with a minimum magnitude of about 5 pCfrom electrical treeing in short, medium-voltage cables could be detected. Location by means of transit time measurements was performed with an accuracy of about 5 cm. In one case, the polarity of the discharge signal was successfully used to locate the discharge to within 1 cm.

Synthesis method of an inductive sensor using Tikhonov regularization procedure

Abstract: It is proposed a synthesis method of designing an inductive position sensor with Tikhonov regularization procedure. Details about the mathematical modeling and numerical solutions obtained are discussed.

Brushless reactance sensors for indicating angular position

Abstract: Angular position detection sensors include a capacitive sensor embodiment and an inductive sensor embodiment. A non-rotating excitation element is electromagnetically coupled to a non-rotating receiver element. The electromagnetic coupling is varied by an electrically passive, rotating element disposed between the non-rotating excitation element and the non-rotating receiver element. Excitation signals applied to the non-rotating excitation element are electromagnetically coupled to the non-rotating receiver element, producing a single output signal directly indicative of the angular position of the rotating element.

Apparatus and methods for an inductive proximity sensor

Abstract: An inductive proximity sensor is disclosed. The proximity sensor includes a housing having at least a first pair of inductive coils disposed within the housing. One of the first pair of inductive coils is opposite in polarity from another one of the first pair of inductive coils. The sensor optionally includes a second set of inductive coils, having opposite polarity.

Sensor System, Sensor Element, and Method for Monitoring a Closing Mechanism

Abstract: In order to be able to reliably detect when an object is caught between two parts which move in relation to one another in a motor-driven closing mechanism, in particular in an electromotively driven window winder system, provision is made for the sensor system to have an optical pressure sensor as well as an electrical capacitive sensor in addition. The optical pressure sensor comprises a light-guiding element, a light source for injecting light into the light-guiding element and a light sensor for sensing the light which has been output. The electrical sensor comprises an electrode which is connected to a voltage source. Both sensors are each assigned to an evaluation unit for evaluating the respective signal.

Metallic debris detection sensor

Abstract: The present invention relates to a sensor arrangement. In particular, a sensor for the measurement of magnetically active or ferrous debris, for example, as generated as a result of machine wear. There is provided a sensor (5) having a magnetic sensor head adapted to produce a magnetic field,- a magnetic field sensor (10) responsive to changes in the magnetic field; a temperature probe (15); and processing means (50) for determining the amount of debris accumulated on the magnetic sensor head based on both magnetic field and temperature data.

The use of time division of the channels in capacitive and inductive sensor measuring circuits

Abstract: The principle of time division of the channels when converting the ratio of passive quantities into an active quantity is proposed. Using this principle, methods are developed which enable errors due to the non-ideal nature of the existing conversion of an amplifier and the parameters of the connecting cable to be eliminated.

Braking system for vehicle has sensors to monitor the position and movement of the brake pedal and braking foot

Abstract: An improved braking system for a vehicle has two sets of sensors to monitor the position and movement of the brake pedal and the braking foot. The first sensor is on the pedal while the second sensor monitors the space between and in front of the control pedals. A processor monitors the sensor outputs and the vehicle dynamics to generate brake control signals, e.g. for emergency braking with a minimum of delay. The second sensor can be a touch pad type foil with an array of resistive, capacitative or inductive sensors and can comprise a number of sections.

Inductive presence or position sensor

Abstract: The present invention relates to an inductive presence or position sensor. Inductive sensor or detector of the type comprising as its sensitive element, preferably defining a front working plane of the sensor, a coil system forming an air-core transformer arrangement with a primary coil or winding and a secondary coil or winding, said primary coil or winding of said system being associated with a capacity component in order to constitute a LC oscillating circuit whose oscillation is sustained by an adapted generator in the form of an operational amplifier and an associated resistance arrangement, the sensor also comprising signal processing means, for example signal adding, amplifying, converting and/or evaluating circuits, fed by at least one signal provided by at least one component of the coil system, inductive sensor (1) characterised in that it comprises a direct or indirect feedback line (11) from the secondary coil or winding (3) to the input of the operational amplifier (6) of the generator (5).

Vehicle has chassis with suspension and assigned shock absorber, where vibration behavior of suspension or shock absorber is monitored using sensor

Abstract: The vehicle has a chassis (1) with a suspension and assigned shock absorber (2), where a vibration behavior of the suspension or the shock absorber is monitored using sensor (5). The sensor is an axial sensor, particularly a potentiometer or an optical or inductive sensor. The sensor is a vibration sensor. A gradient of the vibration behavior is detected with the sensor.

Sensor system, sensor element, and method with a light sensor and an electrical sensor for monitoring a closing mechanism

Abstract: In order to be able to reliably detect when an object is caught between two parts which move in relation to one another in a motor-driven closing mechanism, in particular in an electromotively driven window winder system, provision is made for the sensor system to have an optical pressure sensor as well as an electrical capacitive sensor in addition. The optical pressure sensor comprises a light-guiding element, a light source for injecting light into the light-guiding element and a light sensor for sensing the light which has been output. The electrical sensor comprises an electrode which is connected to a voltage source. Both sensors are each assigned to an evaluation unit for evaluating the respective signal.

Inductive sensor for measuring e.g. rotation speed of shaft, has permanent magnet for generating magnetic field, where closed magnetic path of magnetic flow line comprises air gap, in which rotating component is engaged

Abstract: The sensor (1) has a phonic wheel (4) with a permanent magnet (2) for generating a magnetic field (11). A core (5) comprises a coil (6) attached to a measuring device and wound on the device for detecting magnetic flux change caused by a rotating component. A closed magnetic path of a magnetic flow line comprises an air gap (12), where the rotating component is engaged in the air gap. The gap is formed between opposite front sides of shank ends of a magnetic yoke (10).