Abstract: A system for capacitive detection of seat occupancy in a vehicle comprises a sensing electrode and a shielding electrode arranged in substantially parallel layers. A spacer is arranged between the sensing electrode and the shielding electrode to keep the sensing electrode and the shielding electrode at a certain distance from each other. The spacer comprises an inner textile layer and at least one of the electrodes comprises a film-based electrode.

Abstract: A magnetic suspension supporter for a direct tension test apparatus, includes an upper end cap and a lower end cap for fixing a sample, an upper chain and a lower chain connected to the upper and lower end caps respectively, an upper joint and a lower joint connected to the other ends of the upper and lower chains respectively, the lower joint being fixed to the test machine foundation. In addition, the upper and lower end caps, the upper and lower chains, the upper and lower joints as well as the supporter having a common vertical axis and being arranged in a cascade form, characterized in that a sample supporter is arranged between the lower end cap and the test machine foundation. The sample supporter is composed of a pair of upper magnet provided at the underside of the lower end cap and lower magnet on the upside of the test machine foundation, which constitute two magnets structure. The polarity directions of the two magnets are reversed and the same polarity is arranged oppositely on the axis.

Abstract: The invention relates to a sensor (2) for measuring mechanical stress acting thereon. The invention is characterized in that the sensor has an oscillating, magnetorestrictive resonator plate (3) and the stress to be measured acts on the resonator plate (3) indirectly by way of a variable magnetic field. The variable magnetic field is preferably created by way of a bias plate (5) made of magnetorestrictive material, or at least one permanent magnet (15) as a result of the mechanical stresses acting thereon by the body (7) to be measured.

Abstract: A MEMS piezoresistive resonator (8, 78) is driven at a higher order eigenmode (32) than the fundamental eigenmode (31). The route of flow of a sense current (22) is arranged in relation to a characteristic of the higher order eigenmode (32), for example by being at a point of maximum displacement (50) or at a point of maximum rate of change with respect to distance (x) of displacement of the higher order eigenmode (32). The route of flow of the sense current (22) may be arranged by fabricating the MEMS piezoresistive resonator (8, 78) with a trench (15) formed between two beams (11, 12) of the MEMS piezoresistive resonator (8, 78), the end of the trench being located at the above mentioned position.

Abstract: A sensor apparatus for measuring environmental degradation of a structures making use of exposed sacrificial material coupons mounted in the immediate vicinity of magnetic sensor elements in the environment of the monitored structure.

Abstract: A strain gauge including: a system including a transmission coil, a magnetostrictive material layer and a receiver coil wherein an alternating transmission signal is applied across the transmission coil and an induced signal is induced in the receiver coil, the intensity of the detected signal across the receiver coil being a measurement of strain, wherein frequency of transmission signal is near to a resonance frequency of the system.

Abstract: Improved microwire strain sensor elements (20, 40, 52, 62) and corresponding methods are provided, which permit accurate, wireless strain monitoring of a variety of structures, including composite structures, through use of a remote detector (28). The sensor elements (20, 40, 52, 62) have amorphous or nanocrystalline metallic alloy microwire cores (22, 48), which exhibit substantially reduced remagnetization responses when the sensor elements (20, 40, 52, 62) are coupled with a structure to be strain-monitored, and the structures are in an unstrained condition. When the monitored structure experiences a strain above a pre-selected threshold value, the microwire cores (22, 48) exhibit substantially different remagnetization responses as an indication that the monitored structure has experienced a strain above a strain threshold or over a range of strain.

Abstract: An occupant presence sensor apparatus disposed in a seat includes first and second substantially non-compliant force translation plates generally parallel to the seating surface of the seat, an elastomeric mat disposed between the first and second force translation plates, and a switch mechanism disposed between the first and second force translation plates within an opening formed in the elastomeric mat. The elastomeric mat includes a distributed array of hollow protuberances that extend toward and contact the force translation plates, and the mat has a stiffness that normally provides a clearance between the switch mechanism and one of the force translation plates. When an occupant of specified or higher weight sits on the seating surface, the protuberances collapse and the force translation plates activate the switch mechanism.

Abstract: A tunneling effect element, including an insulating layer that forms a tunneling barrier, a lower electrode that is conductive and non-magnetic, and is formed on a bottom surface of said insulating layer, an upper electrode that is conductive and non-magnetic, and is formed on a top surface of said insulating layer, and a transmission member. The transmission member is made of insulating material that is formed surrounding the insulating layer and the lower and upper electrodes. The transmission member is also formed on a surface of an object to be detected, and transmits deformation of the object to be detected to the insulating layer. The tunneling effect element detects a change in stress of the object to be detected as a change in electric resistance.

Abstract: The disclosed subject matter provides a strain gauge which includes a composite film including a non-metallic matrix and magnetically active particles. At least a portion of the magnetically active particles form one or more chain structures, such that the resistivity of the composite film can vary in response to an applied strain on the composite film. The strain gauge also includes two or more leads affixed to the composite film and electrically coupled with the chain structures. Methods of fabrication and methods of use of the strain gauge based on chain-structured magnetically active particles included in a non-metallic matrix are also disclosed.

Abstract: A method of measuring the retention force of a biomedical specimen coupled to a carrier includes the measurement of the force required for magnetically decoupling the specimen from the carrier. In one embodiment, the method includes the steps of providing the specimen with an electrically conductive structure; creating an external alternating magnetic field near the specimen; increasing the amplitude and/or frequency of the magnetic field; detecting the start of the movement of the specimen on the carrier; and calculating the retention force of the specimen by determining the applied magnetic force on the basis of the parameters of the magnetic field. In other embodiments, the magnetic field may remain constant and the biomedical specimen may be moved through the field at varying speeds.

Abstract: A device and method for use as an adjunct in assuring that a manufactured wire is substantially free of internal flaws. A plurality of successively adjacent wire bending stations are provided, where each station includes means for bending the wire into bending planes which are different for each of the stations. The wire is passed through the successive stations, whereby the different bending planes at each station subject the wire at each station to tensile bending strain at portions of the wire cross-section which are different for each station. As a result the probability is increased that a given internal flaw in the wire will be exposed to the tensile bending strain condition as the wire passes through the successive stations, increasing likelihood of breakage of the wire at the flaw or of flaw magnification to improve detection of the flaw during subsequent wire inspections.

Abstract: In a measuring device for the measurement of forces in a vehicle undercarriage, more particularly of the brake torque on a vehicle undercarriage, e.g. an aircraft landing gear, a sensor is introduced into a hollow connecting element that is transversally loaded by said forces, which sensor produces a measuring signal in function of a deformation of said connecting element. Distance measuring elements which detect the distance of the inner wall of said connecting element from said sensor are used as measuring elements.

Abstract: Sensing strain in an adhesively bonded joint includes inducing a strain wave in the joint, and sensing a change in local magnetic characteristics in the joint.

Abstract: A mechanical property testing device and method for reliably measuring strain and fatigue characteristics of material specimens is described. An input electrical signal is applied to create an electric field around a first piezoelectric member. The resultant deformation of the first piezoelectric member transfers a force to the specimen being tested which transfers a force to a second piezoelectric member causing deformation. The deformation of the second piezoelectric member generates an output electrical field which is measured. The stress state of the specimen is calculated from fundamental material constants and the measured output electrical field.

Abstract: Device and method for determining mechanical stresses in a substrate coating has a substrate holder and actuating element configured as a piezoelectric actuator moveable at least partially in relation to the holed. The actuating element mechanically prestresses the substrate by applying an electric starting voltage to the piezoelectric actuator to cause the actuating element to be partially displacement by a predetermined and/or determinable starting displacement relative to the holed. A coating is applied to a deposition area of the substrates and a change in displacement of the actuating element is determined.

Abstract: A sensor includes a substrate having a mechanically deformable region that is deformable in a direction non-parallel to a surface of the substrate, and a magnetostrictive multi-layer sensor element configured to detect a mechanical deformation of the mechanically deformable region in a direction that is non-parallel to the substrate surface. The multi-layer sensor element includes a sensor layer having a material having a positive or a negative magnetostriction constant. The sensor further includes a device, arranged on the substrate, that is configured to generate a controllable magnetic field by which a performance of the magnetostrictive multi-layer sensor element is influenced, wherein the magnetostrictive multi-layer sensor element exhibits an electrical resistance that is a function of the controllable magnetic field and a deformation of the mechanically deformable region.

Abstract: An inspection method and an inspection apparatus that can easily measure a distribution of residual stress on a surface processed by shot peening, including a state of distribution in a depth direction of a material to be treated in a relatively short time without destroying the material to be treated. A coil provided in the inspection circuit is arranged on a surface processed by shot peening of the inspection target, an alternating current signal is input to the inspection circuit with changing a frequency so that frequency response characteristics of impedance of the inspection circuit is measured and acquired as inspection target data, and the inspection target data is compared to frequency response characteristics of impedance acquired from a sample of which a state of generation of residual stress is found.

Abstract: A foundation for supporting a structure is provided. The foundation includes a foundation body, at least one anchor bolt connecting a lower anchor plate and the structure, a magnetostrictive load measuring sensor for measuring loads on the at least one anchor bolt, the magnetostrictive load measuring sensor being positioned within the foundation body.

Abstract: A strain gauge including: a system including a transmission coil, a magnetostrictive material layer and a receiver coil wherein an alternating transmission signal is applied across the transmission coil and an induced signal is induced in the receiver coil, the intensity of the detected signal across the receiver coil being a measurement of strain, wherein frequency of transmission signal is near to a resonance frequency of the system.

Abstract: A test machine for testing the physical properties of a test specimen is provided. The test machine includes a fixture that applies a first force on the test specimen in a first direction and utilizes magnetic force to bring about the rotation of a fixture to apply a second force on the test specimen in a second direction. The test machine can better simulate field applications where a material may experience, for example compression or tension at the same time it experiences a rotational moment.

Abstract: The present invention relates to a force measuring instrument, having a carrier plate (3), at least one magnet (5), and at least one magnetically sensitive element (6). A tongue element (4) protrudes at least partly from the carrier plate (3) and is joined to a plate element (2). Between the tongue element (4) and the carrier plate (3), an air gap (7) is formed, in which the magnetically sensitive element (6) is positioned. The force to be measured, delivered via the plate element (2), leads to a relative motion between the end, toward the air gap, of the tongue element (4) and the carrier plate (3). This causes a change in the magnetic field geometry in the air gap (7). The present invention also relates to a method for detecting a force.

Abstract: Magnetic or electric field sensors are mounted against a material surface and used for stress, strain, and load monitoring of rotating components such as vehicle drive trains. The stationary sensors are mounted at multiple locations around the component and used assess the stress on the component at multiple rotational positions. The sensor response is typically converted into a material property, such as magnetic permeability or electrical conductivity, which accounts for any coating thickness that may be present between the sensor and mounting surface. The sensors are not in direct contact with the rotating component and are typically mounted on an annular material or ring that encircles the rotating component. Measurements of the annular material properties, such as the stress, are related to the stress on the rotating component and discrete features on the component.

Abstract: Methods are described for the use of conformable eddy-current sensors and sensor arrays for characterizing residual stresses and applied loads in materials. In addition, for magnetizable materials such as steels, these methods can be used to determine carbide content and to inspect for grinding burn damage. The sensor arrays can be mounted inside or scanned across the inner surface of test articles and hollow fasteners to monitor stress distributions. A technique for placing eddy-current coils around magnetizable fasteners for load distribution monitoring is also disclosed.

Abstract: In one embodiment a sensor assembly has a magnetostrictive (MR) element in a sensor housing. The MR element has a sensing part engaged with a wire coil and a frusto-conical sealing part juxtaposed with a fluid the pressure of which is to be sensed.

Abstract: In one embodiment, a sensor assembly has a sensor housing forming a fluid chamber having a surface defining a normal axis. A magnetostrictive (MS) core that defines a central longitudinal axis is subjected to stress induced by pressurized fluid in the chamber. An excitation coil is coupled to the core to induce a magnetic flux therein. The central longitudinal axis of the core is coaxial with the axis normal to the fluid chamber surface.

Abstract: In one embodiment, a sensor assembly has a sensor housing forming a fluid chamber and a magnetostrictive wire that undergoes stress induced by fluid in the chamber. The wire defines opposed ends, each being associated with a respective terminal. Respective hermetic seals penetrate the housing and are coupled to the respective terminals.

Abstract: A system for measuring stress including a coilless sensor including at least one band of electrically conductive and magnetostrictive material, the band having a first end and a second end defining a gap therebetween, a measuring circuit electrically connected to the first and second ends of the coilless sensor, the measuring circuit being configured to pass a current through the coilless sensor and measure at least one of an inductance, a resistance and an impedance of the coilless sensor in response to the current, and a processor in electrical communication with the measuring circuit, the processor being configured to calculate an amount of stress being applied to the coilless sensor based upon the measured inductance, resistance and impedance.

Abstract: A system for displaying graphical information indicative of a plurality of material characteristics for a portion of a part under test. Energy is directed at the selected portion of the part under test. Resultant energy is detected from the selected portion of the part under test and data representative of each of a plurality of material characteristics for the portion of the part under test is obtained based, at least in part, upon the detected energy. A plurality of graphs is formed based upon the obtained data. Each of the graphs has information indicative of a separate one of the plurality of material characteristics. The plurality of graphs is displayed discrete from each other in a manner that facilitates substantially simultaneous visual comparisons between the information contained in each of the plurality of graphs.

Abstract: A variable reluctance load cell for measuring the static or slowly fluctuating load, or tension, on devices is contained in a support tube. A sensor in the tube utilizes opposing C and I shaped magnetic cores attached to opposing ends of the support tube. A magnetic circuit is formed having an inductance defined by the size of the gap between the magnetic cores with the reluctance dominated by the gap. The sensor inductance is coupled with a fixed, predetermined capacitance in a resonant LC circuit, and the resonant frequency is a function of the gap. The sensor is in a cavity within the tube, and the cavity is sealed in a manner that prevents water or other damaging agents from entering the sensor. In this manner, mounting the sensor and tube to a static device and measuring the AC voltage at the sensor, the amount of load, or stress can be determined.

Abstract: A method and structure for an integrated circuit comprising a first transistor and an embedded carbon nanotube field effect transistor (CNT FET) proximate to the first transistor, wherein the CNT FET is dimensioned smaller than the first transistor. The CNT FET is adapted to sense signals from the first transistor, wherein the signals comprise any of temperature, voltage, current, electric field, and magnetic field signals. Moreover, the CNT FET is adapted to measure stress and strain in the integrated circuit, wherein the stress and strain comprise any of mechanical and thermal stress and strain. Additionally, the CNT FET is adapted to detect defective circuits within the integrated circuit.

Abstract: There is disclosed a knitted transducer device comprising a knitted structure having at least one transduction zone, in which the transduction zone is knitted with electrically conductive fibres so that deformation of the knitted structure results in a variation of an electrical property of the transduction zone.

Abstract: Sensors for outputting signals indicative of a magnetic drag force between a ferromagnetic sample that is or has been in motion relative to one or more measurement magnets are described. Such sensors include at least one measurement magnet and a sensing element operably associated therewith, such that upon or after exposure of the measurement magnet(s) to a ferromagnetic sample in motion relative thereto, the sensor can sense the drag force, if any, or changes therein, experienced by the measurement magnet. Devices for detecting and/or measuring magnetic drag force that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: A change in a magnetic resistance generated between a plurality of windows 23a of a cylindrical member 23 formed by a nonmagnetic material and an output shaft 2 formed by a magnetic material through a torsion of a torsion bar 22 is regarded to be a change in inductances of detecting coils 15p and 15q to detect a steering torque. Coil yokes 16P and 16Q accommodating the detecting coils therein are disposed coaxially on an outer periphery of the cylindrical member 23, and L-shaped bent tip portions of output terminals 15a1 and 15a2 of the detecting coils are inserted into a through hole 18 of a circuit board of a control module CM. The coil yokes 16P and 16Q can easily be attached to a gear box with a rotation and the tip of the output terminal can be arranged with high precision. Terminal holding portions 16P1 and 16Q1 are provided on an inside of a moving track (a circular arc S) so that an interference with other components can be prevented.

Abstract: A magnetic field sensor apparatus includes a first magnetic field sensor and a second magnetic field sensor, arranged on a substrate in a spaced manner from each other, a first temperature sensor with an output for a first temperature sensor signal, a second temperature sensor with an output for a second temperature sensor signal, a first stress sensor with an output for a first stress sensor signal, and a second stress sensor with an output for a second stress sensor signal, wherein the first temperature sensor and the first stress sensor are arranged more closely to the first magnetic field sensor or at a location identical with the first magnetic field sensor, and the second temperature sensor and the second stress sensor are arranged more closely to the second magnetic field sensor than to the first magnetic field sensor or at a location identical with the second magnetic field sensor.

Abstract: A capacitance-type sensor for detecting a condition of an occupant on a vehicle seat includes an electrode. The electrode is disposed within a detection area in the vehicle seat. The electrode generates an electric field. The detection area is based on a surface pressure distribution obtained when an adult sits on the seat.

Abstract: A magnetostrictive load sensor includes an upper casing, a lower casing, a coil, and a bobbin. The upper casing having an approximate bell shape has an upper end that is provided with an opening and a lower end that is provided with a notch. The lower casing includes a disk-shaped member and a bar-shaped member that are integral with each other. The coil is formed by winding a conducting wire around the bobbin. A predetermined position of the bobbin is provided with a lead wire outlet for taking out the conducting wire of the coil. A method of manufacturing the magnetostrictive load sensor includes inserting the bar-shaped member into the axial center of the bobbin, and covering the lower casing with the upper casing. In this way, the notch of the upper casing and the lead wire outlet of the bobbin are fitted with each other. An upper end of the bar-shaped member projects through the opening of the upper casing.

Abstract: A load sensor includes a housing and a magnet carrier axially movable within the housing. A first and a second magnet are coupled to the magnet carrier in an axially spaced apart arrangement and oriented to provide repelling magnetic fields. The magnet carrier and the first and second magnets are axially movable relative to the magnetic field sensor, and the magnetic field sensor is configured to provide an output that is indicative of the position of the magnetic filed sensor relative to the first and second magnets.

Abstract: A strain sensor includes a load carrying body configured to strain in response to a load applied along a load path. The sensor further includes a magnetostrictive electrical conductor affixed to the body but out of the load path. Application of the load causes the body to strain, which in turn results in a proportional stress being imparted to the magnetostrictive conductor, altering its magnetic permeability. A circuit is electrically connected to the conductor to detect such changes in permeability, which are indicative of the applied load.

Abstract: There is described a sensing apparatus comprising first and second members which are supported relative to each other by a support means. The first member comprises a magnetic field generator for generating a magnetic field and the second member comprises an aerial for monitoring the magnetic field generated by the magnetic field generator. At least one of the first and second members is locally deformable relative to the other of the first and second members in order to vary at least one of the magnetic field generated by the magnetic field generator and the electromagnetic coupling between the magnetic field generator and the receive aerial so that, in response to a local deformation, a signal is induced in the receive aerial indicative of the position of the local deformation.

Abstract: A magnetic pressure sensor device comprises at least one magnetic layer able to vary a magnetisation associated thereto in response to a pressure (P) exerted thereon. The device comprises a plurality of layers arranged in a stack, the magnetic layer able to vary a magnetisation associated thereto in response to a pressure (P) comprising a free magnetic layer, able to be associated to a temporary magnetisation (MT), the free magnetic layer belonging to said plurality of layers, which further comprises at least a spacer layer and a permanent magnetic layer associated to a permanent magnetisation (MP). The sensor device further comprises a compressible layer and a layer with high magnetic coercivity associated to the plurality of layers.

Abstract: The present invention relates to the field measuring the mechanical response of micro-electro-mechanical systems. More specifically, the present invention pertains to a method and apparatus that allows the direct control of the load applied to a Micro-Electro-Mechanical System in order to measure the mechanical response. The system comprises a loading sub-system, a displacement measurement sub-system, and an optional observation sub-system.

Abstract: The invention relates to a load gauge comprising a generator-sensor assembly. Said assembly comprises a generator unit that generates a magnetic field and a sensor unit that is sensitive to magnetic fields, said generator unit and sensor unit being displaceable by a force in relation to one another. According to the invention, the generator unit comprises at least one permanent magnet and a second permanent magnet, each with a geometric cross-section that remains essentially constant in a longitudinal direction. The first permanent magnet and the second permanent magnet are situated at an angle to one another.

Abstract: A strain gauge sensor system and method for measuring the strain in a member, such as a fiber rope, has a sensor target assembly having a plurality of magnets carried spaced apart by individual gauge lengths along the member. Position and trigger sensor devices are configured spaced apart along side a desired path of travel of the member. When the member is fed along the desired path of travel, the trigger sensor device, in response to magnetically sensing a passing magnet, triggers the position sensor device to read the position of an adjacent passing magnet. The strain in the gauge length is determined from the read position. RFID tags placed on the member between the magnets can be identified by an RF reader to identify a particular gauge length being measured. The system can include a deployment device for feeding the member along the desired path.

Abstract: A force sensor includes a shaft to which a magnet is fixed, and a case which can reciprocate with respect to the shaft and to which a Hall IC element is fixed. The Hall IC element outputs an output voltage which changes in accordance with relative displacement between the Hall IC element and the magnet. A main spring is interposed between the shaft and the case and elastically deforms in accordance with force produced between the shaft and the case in the reciprocating direction. A sub spring is provided in order to impart a preload such that when the amount of elastic deformation of the main spring is substantially zero, no axial clearance is formed between a flange portion of the shaft and one end portion of the main spring, and no axial clearance is formed between the case and the other end of the main spring.

Abstract: Sensors for outputting signals indicative of a magnetic drag force between a ferromagnetic sample that is or has been in motion relative to one or more measurement magnets are described. Such sensors include at least one measurement magnet and a sensing element operably associated therewith, such that upon or after exposure of the measurement magnet(s) to a ferromagnetic sample in motion relative thereto, the sensor can sense the drag force, if any, or changes therein, experienced by the measurement magnet. Devices for detecting and/or measuring magnetic drag force that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: A tight-fitting garment comprising a dipole resonator which is adapted to vary its length and/or shape in conformity with the length and/or shape variations of a person wearing the garment. The length and/or shape of the resonator determines the resonance frequency which can be detected by a reflection analyser. The dipole resonator comprises at least one elastic core around which a conductive wire is wound. The dipole resonator is further suitable to elastically deform along with the tight-fitting garment.

Abstract: A test machine for testing the physical properties of a test specimen is provided. The test machine includes a fixture that applies a first force on the test specimen in a first direction and utilizes magnetic force to bring about the rotation of a fixture to apply a second force on the test specimen in a second direction. The test machine can better simulate field applications where a material may experience, for example compression or tension at the same time it experiences a rotational moment.

Abstract: A method and apparatus for measuring stress or strain in a portion of a ferromagnetic member is disclosed in which advantage is taken of the fact that the magnetic properties of a ferromagnetic member change with applied tensile or compressive stress. A magnetic hysteresis loop is measured in a portion of a ferromagnetic member and a model of a magnetic hysteresis loop is fitted to the measured magnetic hysteresis loop by varying at least one stress or strain dependent model variable and the fitted at least one variable is used to determine the stress or strain of the portion. The particular model disclosed is a predator/prey pursuit model wherein the prey is the applied field and the predator is the flux density.

Abstract: The present invention is directed to a strain sensor comprising a monolithic magnetostrictive material core wherein the permeability of the material depends on stress, the core having an aperture therein and a coil wound about the core and through the aperture. The core and the coil being configured such that when the coil is connected in circuit, it establishes a loop of magnetic flux that circulates through the core and about the coil whereby impedance of the core is measured. Impedance being a general term including inductance, resistance and a combination of the two. Various configurations for the core are disclosed and integrated housing is also taught. The present sensor can be used to sense force, pressure, torque, acceleration and combinations thereof. The present device can be utilized to sense pressure of diesel fuel in diesel engines, oil pressure, hydraulic pressure, and earth moving and construction vehicles, etc.