Abstract: A fluid actuator arrangement comprises a piston rod member, at least two cylinders each said cylinder having a piston body, and a clamping mechanism associated to each cylinder. Each clamping mechanism is arranged to engage and disengage the piston body of the cylinder to the piston rod member. The fluid actuator arrangement comprises further a control element arranged to control a back and forward movement of the respective piston body so that forward movement is slower than the backward movement and to control the movement of the respective piston bodies in relation to each other such that at least one piston body is always moving forward and such that an overlap exists wherein at least two of the piston bodies are moving forward simultaneously during a cycle.

Abstract: A method of measuring thickness of a material generally includes applying an oscillating signal to a first electrode at a fixed frequency, passing the signal through the material to a second electrode, and measuring the magnitude of the signal reflected back to the first electrode. The thickness of the material is determined based on the measured magnitude of the reflected signal by: 1) comparing the determined magnitude to a predetermined baseline to establish a difference; and 2) identifying the thickness based on the difference. Related apparatuses are also disclosed. The material may be a vehicle tire.

Abstract: In one embodiment, a method includes transmitting, from a first transducer of an electronic device, a first audio signal to a surface near the electronic device. The first audio signal is generated based on a frequency sweep across a range of frequencies. The method also includes receiving, at a second transducer of the electronic device, a second audio signal that is at least partly reflected off the surface. The method then determines an attribute of the surface based on the received second audio signal.

Abstract: An internal probe device for insertion into the body of a patient, comprises an elongate body with a plurality of EAP actuators mounted at the surface of the body. The EAP actuators are made to vibrate so that their position becomes visible in a Doppler ultrasound image. The use of EAP actuators to provide vibrations enables individual locations to be identified. In particular, the movement of the EAP actuator may be largely isolated from the main body of the probe. Furthermore, EAP actuators can be thin, lightweight and have a small form factor suitable for application to or within the surface of a probe, such as a catheter, needle or endoscope.

Abstract: A hybrid switch apparatus includes a standard semiconductor switch and a fast semiconductor switch electrically arranged in parallel to form a joint output current path for carrying a load current. The standard switch may be a silicon (Si) MOSFET while the fast switch may be a GaN high electron mobility transistor (HEMT). A means for producing first and second gate drive signals includes a pulse former. The first gate drive signal is applied the standard switch for selectively turning the standard switch on and off. The pulse former outputs the second gate drive signal for driving the fast switch, where the pulse former generates the second gate drive signal as a switch-on pulse starting synchronously with each transition of the first gate drive signal and which generates the second gate drive signal in an OFF state in between pulses to avoid incurring a conduction loss in the fast switch.

Abstract: Provided is a technology which is able to detect an object with high accuracy. A signal processing apparatus 1 includes a generating unit 2 and a detecting unit 3. The generating unit 2 includes a function of generating, as a transmitting signal, a modulation wave whose frequency changes non-repetitively. The detecting unit 3 includes a function of fetching the transmitting signal and a receiving signal which is received by a receiving means that can receive a reflection signal generated when the transmitting signal is reflected by an object. The detecting unit 3 includes a function of detecting at least one of presence of the object, distance to the object, and moving speed of the object, based on correlation between the receiving signal and the transmitting signal.

Abstract: Apparatus and method for detecting a position of an actuator piston driving a valve pin in an injection molding system. The apparatus includes an actuator housing having a body portion, surrounding an axial bore, of a substantially non-magnetic and/or magnetically permeable material, a piston, movable within the axial bore for driving a valve pin, the piston including a magnetic member generating a magnetic field such that axial movement of the piston in the bore modifies the magnetic field according to the position of the piston relative to a detection position, and a magnetic field detector attached to an exterior surface of the body portion at the detection position for detecting the magnetic field associated with the position of the piston and generating an output signal determined by the piston position.

Abstract: Provided herein is a device for measuring a thickness of a dielectric layer on a base substrate. The device is provided with a cylindrical resonant cavity having a circular cylindrical wall and a plane wall on one end thereof, wherein the opposite end is open to be placed upon the dielectric layer on the substrate to form a wall of the resonant cavity on the opposite end; an antenna located within the resonant cavity and adapted to excite an electromagnetic field in the resonant cavity that is approximately zero in the dielectric layer; a reflection meter connected to the antenna and adapted to measure the resonant frequency of the resonant cavity; and a processor connected to the reflection meter. Also provided herein is a method for measuring a thickness of a dielectric layer on a base substrate having a curved surface.

Abstract: Wireless strain and displacement sensors wirelessly monitor structural health and integrity, and are made by printing inductor-interdigital capacitor sensing circuits on a variety of substrates, including ceramic substrates, with thermally processable conductive inks. Sensors of the invention can be employed to detect strain and displacement of civil structures, such as bridges and buildings. The sensors include sensing elements that are mounted or printed on stiff, inflexible substrates, which prevent the sensing elements from bending, stretching, or otherwise warping when the sensor is strained. An interlayer between the sensing elements allows the sensing elements to move with respect to each other during application of strain. Thus, strain causes the sensing elements to move but not to deform, causing changes in sensor resonance that can be detected through wireless radio-frequency interrogation.

Abstract: In a smart card having an antenna structure and a metal layer, an insulator layer is formed between the antenna structure and the metal layer to compensate for the attenuation due to the metal layer. The thickness of the insulator layer affects the capacitive coupling between the antenna structure and the metal layer and is selected to have a value which optimizes the transmission/reception of signals between the card and a card reader.

Abstract: The invention relates to a device for measuring a thickness of a dielectric layer (8) on a base substrate (7), comprising a cylindrical resonant cavity (1) having a circular cylindrical wall (9) and a plane wall (10) on one end thereof, wherein the opposite end (3) is open to be placed upon the dielectric layer (8) on the substrate (7) to form a wall of the resonant cavity (1) on the opposite end (3); an antenna (4) located within said resonant cavity (1) and adapted to excite an electromagnetic field in the resonant cavity (1) that is approximately zero in the dielectric layer (8); a reflection meter (5) connected to said antenna (4) and adapted to measure the resonant frequency of the resonant cavity (1); and a processor (6) connected to said reflection meter (5) and adapted to determine the thickness of the dielectric layer (8) from the resonant frequency of the resonant cavity (1).

Abstract: A device for detecting metal elements in slab form such as metal plates or sheets, includes an emission coil powered by suitable control elements and generating a magnetic field, a reception coil placed so as to enable generation via induction of a voltage across the terminals of the coil under the action of the magnetic field, and elements for processing and evaluating the voltage signal delivered by the at least one reception coil, enabling delivery of an information signal indicating the absence or presence of one or more metal elements near the coils. The emission coil (3) and the reception coil (5) are both mounted in a housing or a sensor head having an active detection face having an associated detection region, and are positioned at a defined inclination one relative to the other and relative to the face.

Abstract: The subject invention relates to an air spring height sensor. The air spring height sensor of this invention comprises a height measuring signal transmitter (102) and a receiver (101). The height measuring signal transmitter is adapted for transmitting a height signal. The receiver is adapted for sensing the height signal transmitted by the height measuring signal transmitter. The height signal indicates a distance between the height measuring signal transmitter and the receiver.

Abstract: A method for providing an in-vivo assessment of relative movement of an implant that is positioned in a living being is provided wherein a first assembly and a second assembly are positioned within the living being. The first assembly includes a passive electrical resonant circuit that is configured to be selectively electromagnetically coupled to an ex-vivo source of RF energy and, in response to the electromagnetic coupling, generates an output signal characterized by a frequency that is dependent upon a distance between the first assembly and the second assembly at the time of the electromagnetic coupling.

Abstract: Disclosed is a sensor that can accurately detect displacement and prevents the phenomenon of a contact section between a shaft member and a sliding element receiver being shifted. The sensor comprising: a case having a through hole; a resistance substrate fixed at an inside of said case; a shaft member having a first end portion which is one end of the shaft member placed within said case and a second end portion which is other end of the shaft member exposed to an outside of said case from said through hole, said shaft member being placed at said through hole in a movable manner in an axial direction; and a sliding element receiver having a bearing end contacting with said second end portion of said shaft member, and attached with a brush sliding together with said resistance substrate, said sliding element receiver being capable of moving relatively against said resistance substrate with said shaft member. A hemispherical end face is formed at said first end portion.

Abstract: A method and device for measuring the position of sections with an absorbing substance in multi-segment filter rods of the tobacco processing industry by measuring a varying shift of the resonance frequency A and/or spread of the resonance line B during movement of the rod in the longitudinal direction, using a microwave resonator, which has a field concentration in a spatial area, wherein this spatial area is smaller in the rod direction than the segment length to be determined, forming a difference quotient ?A of the resonant frequency shift A and/or ?B of the resonance line spread B relative to the longitudinal direction, determining local extreme values of the respective difference quotients, and assigning local extreme values as a position of a transition from a section with higher content of absorbing substance to a section without, or with lower content, of absorbing substance, and vice versa.

Abstract: Methods and systems for determining one or more parameters of a tuned circuit forming part of a wireless energy transmission system in an implanted (or implantable) medical device are described. The method involves energising the tuned circuit then receiving a signal back from it. This signal is then analysed to determine a property of the circuit such as its quality factor (Q) or resonant frequency. Also described herein is a method and system for determining the implantation depth of a component of an implanted medical device. The method involves determining the position of a magnetic element which is mounted in a fixed physical relationship with the component of the medical device. The methods can be performed on an implanted medical device without the need to explant the device.

Abstract: Apparatus is provided for determining the clearance between a member and a casing surface over and relative to which the member moves, e.g. in a gas turbine engine. The apparatus includes a main waveguide and a reference element that is provided at a position intermediate the proximal and distal ends, or at the distal end, of the waveguide. The transmitter/receiver is arranged to transmit an electromagnetic signal through the main waveguide and receive (i) a first portion of the electromagnetic signal reflected from the reference element, (ii) a second portion of the electromagnetic signal reflected from the casing surface, and (iii) a third portion of the electromagnetic signal reflected from the member, allowing the relative positioning of the reference element, the casing surface and the member to be simultaneously determined.

Abstract: A method of detection of a distance variation with respect to an axis of at least one point of an object rotating around this axis by a terminal at a fixed position with respect to the axis and capable of emitting a radiofrequency field for at least one resonant circuit attached to the object. The method includes the steps of measuring and recording, on the terminal side, a maximum value of a quantity representative of the coupling between an oscillating circuit of the terminal and the at least one resonant circuit; and detecting a variation of this periodic maximum.

Abstract: A microwave sensor assembly includes a signal generator for generating at least one microwave signal and an emitter coupled to the signal generator. The emitter is configured to generate an electromagnetic field from the at least one microwave signal, wherein the emitter is detuned when an object is positioned within the electromagnetic field such that a loading signal is generated. The microwave sensor assembly also includes a detector coupled to the emitter and to the signal generator. The detector is configured to calculate at least one of an amplitude, a phase, and a power of the loading signal at a primary frequency of the loading signal for use in measuring a proximity of an object to the emitter.

Abstract: A system and method by which thickness of a dielectric film on substrates can be noninvasively determined is invented. The system and method are especially applicable to areas and applications where traditional techniques have proven unsuccessful or limited. According to embodiments of the present invention the present system and method can be used to measure film thickness in confined and inaccessible locations, and on substrates of complex geometry. The method can be used with an arbitrary and time varying orientation of the substrate-film interface. The measurements of the film thickness on the inside of open or enclosed channels of an arbitrary geometry, and on flexible substrates are possible. With multiple embedded sensors, the film thickness in different lateral locations can be simultaneously measured. The dielectric permittivity of the FUT as a function of the distance from the substrate of the film can also be measured.

Abstract: An occupant detection system that includes an electrode arranged proximate to an expected location of an occupant for generating an electric field between the electrode and the occupant proximate thereto. An electrical network coupled to the electrode forms a resonant circuit that includes the occupant as part of the resonant circuit. A controller coupled to the resonant circuit is configured to determine a resonant frequency of the resonant circuit indicative of an occupant presence, and a network signal magnitude at the resonant frequency indicative of a humidity value proximate to the electrode. 7. A method for detecting a vehicle applies an excitation signal to the resonant circuit, determine a resonant frequency of the resonant circuit and determines a humidity value based on a network signal magnitude at the resonant frequency.

Abstract: Probes of a conductor length measurement device are connected to piping, and an output voltage is applied to the piping through the probes. A frequency spectrum curve is subsequently calculated by subjecting a voltage signal to FFT. Resonant frequencies of the piping are then determined from this frequency spectrum curve, and the total length of the piping is calculated on the basis of the resonant frequencies. The total length of the piping can therefore be easily measured without the need to install, for example, any measurement instruments at branch terminals.

Abstract: A capacitance sensing apparatus for use in a position sensing apparatus, comprising a first set of electrodes and a second set of electrodes and a capacitance sensing circuit arranged to determine, in use in a normal operating mode, the capacitance between each pairing of electrodes comprising one from the first set and one from the second set, in which the apparatus is further provided with at least one group switch arranged to selectively electrically connect together groups of the electrodes within the sets of electrodes, in which, in use in a low resolution mode of the apparatus the or each group switch connects together the groups of electrodes and the capacitance sensing circuit is arranged to determine the capacitance between the each pairing of groups of electrodes in one set and the electrodes or groups of electrodes of the other set. Typically, the apparatus is used in conjunction with a display to form a touch-sensitive display.

Abstract: A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling.

Abstract: A proximity sensor includes a relatively simple health monitoring circuit. The proximity sensor includes a variable gain oscillator, a feedback circuit, and a proximity determination circuit. The variable gain oscillator has a gain that varies with the proximity of a target to a sensor coil, generates an oscillating electrical signal having a substantially constant amplitude magnitude, and generates an energy signal representative of the electrical energy needed to sustain oscillations. The feedback circuit supplies feedback to the oscillator, and the proximity determination circuit, based on the energy signal, supplies a proximity signal representative of target proximity to the sensor coil. The health monitor circuit also receives the oscillating electrical signal and supplies a health status signal representative of proximity sensor health.

Abstract: Disclosed are embodiments of on-chip identification circuitry. In one embodiment, pairs of conductors (e.g., metal pads, vias, lines) are formed within one or more metallization layers. The distance between the conductors in each pair is predetermined so that, given known across chip line variations, there is a random chance (i.e., an approximately 50/50 chance) of a short. In another embodiment different masks form first conductors (e.g., metal lines separated by varying distances and having different widths) and second conductors (e.g., metal vias separated by varying distances and having equal widths). The first and second conductors alternate across the chip. Due to the different separation distances and widths of the first conductors, the different separation distances of the second conductors and, random mask alignment variations, each first conductor can short to up to two second conductors.

Abstract: A method and apparatus for determining the attenuation of an RF signal caused by a DPF at an unknown or different ambient temperature than the temperature used for DPF sensor calibration is disclosed. The method and apparatus determine the sensor attenuation just prior to determining the DPF attenuation by disconnecting the antennas and determining the attenuation of a loopback path. This sensor attenuation can then be deducted from the attenuation determined for the normal path that includes the attenuation caused by the loopback path, the cables, and the DPF. This method compensates for variation in the attenuation of the sensor caused by changes in ambient temperature of the sensor. Further temperature compensation is be achieved by determining additional factors to account for variations caused by changes in ambient temperature.

Abstract: A microwave sensor assembly includes a signal generator for generating at least one microwave signal and an emitter coupled to the signal generator. The emitter is configured to generate an electromagnetic field from the at least one microwave signal, wherein the emitter is detuned when an object is positioned within the electromagnetic field such that a loading signal is generated. The microwave sensor assembly also includes a detector coupled to the emitter and to the signal generator. The detector is configured to calculate at least one of an amplitude, a phase, and a power of the loading signal at a primary frequency of the loading signal for use in measuring a proximity of an object to the emitter.

Abstract: A method for measuring a proximity of a component with respect to a microwave emitter is provided. The method comprises transmitting at least one microwave signal to the microwave emitter. At least one electromagnetic field is generated by the microwave emitter from the microwave signal. Moreover, the method comprises inducing a loading to the microwave emitter by an interaction between the component and the electromagnetic field, wherein at least one detuned loading signal representative of the loading is reflected within a data conduit from the microwave emitter. The detuned loading signal is received by at least one signal processing device. The signal processing device then measures the proximity of the component with respect to the microwave emitter based on the loading signal. An electrical output is generated by the signal processing device.

Abstract: According to an aspect of the invention, there is provided a method for determining whether first and second components of a vehicle are physically coupled together, the method comprising: transmitting a first signal from the first component of the vehicle; receiving a second signal from the second component of the vehicle; processing the second signal to determine whether the first and second components of the vehicle are coupled.

Abstract: A method and system for calibrating a plurality of measurement systems. The method includes obtaining a first plurality of calibration standards. The first plurality of calibration standards is associated with a plurality of predetermined values. Additionally, the method includes measuring the first plurality of calibration standards by a plurality of measurement systems to obtain a first plurality of measured values, processing information associated with the first plurality of measured values, and selecting a first measurement system from the plurality of measurement systems based on at least information associated with the first plurality of measured values. Moreover, the method includes calibrating the first measurement system with the first plurality of calibration standards, obtaining a second plurality of calibration standards, and measuring the second plurality of calibration standards by the first measurement system to obtain a second plurality of measured values.

Abstract: An ultrasonic diagnostic apparatus includes plural ultrasonic transducers, a catheter signal detection unit and a position detection unit. The plural ultrasonic transducers are arrayed two-dimensionally for transmitting and receiving ultrasonic waves to and from an object. The catheter signal detection unit is configured to acquire a reception signal of a frequency modulated continuous wave from reception signals from at least three of the plural ultrasonic transducers. The frequency modulated continuous wave is transmitted from a catheter inserted in the object. The position detection unit is configured to detect a position of the catheter based on the acquired reception signal of the frequency modulated continuous wave.

Abstract: A system and apparatus for providing an in-vivo assessment of relative movement of an implant that is positioned in a living being is provided that includes a first assembly and a second assembly that are positioned within the living being. The first assembly includes a passive electrical resonant circuit that is configured to be selectively electromagnetically coupled to an ex-vivo source of RF energy and, in response to the electromagnetic coupling, generates an output signal characterized by a frequency that is dependent upon a distance between the first assembly and the second assembly at the time of the electromagnetic coupling.

Abstract: A load impedance decision device, a wireless power transmission device, and a wireless power transmission method are provided. At least one of a distance and an angle between two resonators may be measured. A load impedance may be determined based on at least one of the measured distance and the measured angle. When the distance between the two resonators changes, a high power transfer efficiency may be maintained without using a separate matching circuit. Where the load impedance is determined, a test power may be transmitted. Depending on a power transfer efficiency of the test power, the load impedance may be controlled and power may be wirelessly transmitted from the source resonator to the target resonator.

Abstract: A method of detection of a distance variation with respect to an axis of at least one point of an object rotating around this axis by a terminal at a fixed position with respect to the axis and capable of emitting a radiofrequency field for at least one resonant circuit attached to the object. The method includes the steps of measuring and recording, on the terminal side, a maximum value of a quantity representative of the coupling between an oscillating circuit of the terminal and the at least one resonant circuit; and detecting a variation of this periodic maximum.

Abstract: A method for measuring surface properties according to the present invention includes the steps of: with distance control feedback applied so that a desired physical quantity to be measured that is attributed to an interaction between a probe and a sample is actually measured while changing a measured distance between the probe and the sample in accordance with a relationship between the desired physical quantity and the measured distance, (i) setting a set value, corresponding to the desired physical quantity, which serves to change the measured distance; and (ii) recording, for each set value thus set, a relationship between the measured distance changed by the set value set in the step (i) and a physical quantity measured with the probe and the sample placed at that measured distance. This allows precise and quick measurement of a physical quantity even in a region where the probe and the sample are very close to each other, while avoiding a collision between them.

Abstract: A microwave paint thickness sensor includes a single cylindrical cavity, a microwave source, and a signal detector. The cylindrical cavity is open at one end, the open end having a choke joint for interfacing with a painted surface. The cylindrical cavity is designed so that the electronic field is normal to the painted surface. In a preferred embodiment, this is accomplished by providing an optimally designed TM011 mode cavity. In this configuration, the resonant frequency of the cavity is linearly related to the inverse of the paint thickness. In accordance with one aspect of the present invention, the resonant cavity is optimally sized to resonate at a frequency where the sensor footprint can be minimized. Thus with the use of the choke joint, the small sensor interface area of the present invention may easily be applied to a curved surface.

Abstract: Systems and methods are disclosed for evaluating the length of elongated elements in a sample. The disclosed systems and methods may include using a direct current stimulus to determine a direct current base length region corresponding to at least a portion of the sample. Furthermore, the disclosed systems and methods may include using an alternating current stimulus to determine that the direct current base length region corresponds to a first set of elongated elements and a second set of elongated elements. The first set of elongated elements may have a first base length and the second set of elongated elements may have a second base length. The elongated elements may comprise, for example, chain molecules, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), or proteins. Furthermore, the disclosed systems and methods may include measuring an ion current through a nanopore, the ion current produced by the alternating current stimulus.

Abstract: An electronic status detection device for wireless detection of at least one status of an apparatus, wherein the status detection device comprises at least two resonant circuits, of which at least one resonant circuit is active and one resonant circuit is passive, wherein the active resonant circuit comprises at least one control device. A status detection device such as this makes it possible, for example, to reliably detect the presence or the absence of belt clips in safety belt locks.

Abstract: An apparatus is disclosed for measuring a variable angular position of a movable part. The apparatus comprises at least two resonators formed by coupled slow-wave structures, and at least two movable targets having electrodynamic profiles, the targets also having a variable angular position. The angular position of the target is representative of the angular position of the movable part. An electromagnetic field is excited in the resonators at a frequency at which electromagnetic parameters of the resonators depend upon the position of the targets. A change in the angular position of the targets therefore causes a change in electrodynamic parameters of the resonators. The change in the electrodynamic parameters of the resonators is converted into a reading, such as an output voltage, which is indicative of the measured angular position.

Abstract: A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling.

Abstract: A microwave paint thickness sensor includes a single cylindrical cavity, a microwave source, and a signal detector. The cylindrical cavity is open at one end, the open end having a choke joint for interfacing with a painted surface. The cylindrical cavity is designed so that the electronic field is normal to the painted surface. In a preferred embodiment, this is accomplished by providing an optimally designed TM011 mode cavity. In this configuration, the resonant frequency of the cavity is linearly related to the inverse of the paint thickness. In accordance with one aspect of the present invention, the resonant cavity is optimally sized to resonate at a frequency where the sensor footprint can be minimized. Thus with the use of the choke joint, the small sensor interface area of the present invention may easily be applied to a curved surface.

Abstract: A method of diagnosing corrosion risk of a buried pipe due to DC stray currents and/or AC voltages induced in soil employs a metal probe including a first, exposed part having a first specific resistivity, and a second, sealed reference part having a second specific resistivity. The probe is buried in the soil, and the AC current and voltage between the pipe and the probe are measured, from which the spread resistance is determined. The resistances of the first and second probe parts are determined by respectively passing first and second excitation currents through the first and second probe parts and measuring the voltages across them. The resistance measurements are stored, and the steps are repeated periodically. The corrosion of the first probe part is determined from the measurements according to an algorithm, and the pipe corrosion risk is diagnosed from an empirical combination of the corrosion of the first probe part, the spread resistance, and the AC voltage measured.

Abstract: A method for determining a distance between a first piece and a second piece includes measuring, at the first or second piece, a first signal at a first frequency, and measuring, at the first or second piece, a second signal at a second frequency. The second frequency is different from the first frequency. The distance is determined based on the measured first and second signals.

Abstract: A device and method are provided for measuring distance in a pneumatic spring with a metal base and cover. The device includes an electrically conductive spring element positioned between a metal base and cover of the pneumatic spring to form a microwave cavity resonator.

Abstract: A tracking system of the present invention includes a transponder 20 attached on a moving object 2 and an autonomous mobile unit 1 for tracking the transponder 20. The autonomous mobile unit 1 has an environment detecting means for acquiring reflection environment information relating to a wall surface 6a, 6b and 6c existing in the vicinity. In this system, the following tracking cycle is executed. The autonomous mobile unit 1 transmits a first ultrasonic wave, and upon receipt of it, the transponder 20 transmits a second ultrasonic wave. By receiving the second ultrasonic wave, the autonomous mobile unit 1 acquires reception information relating to a direct wave that directly arrives at the autonomous mobile unit 1 from the transponder 20 and a reflected wave that arrives via the wall surface.

Abstract: An apparatus is disclosed for measuring the angular position of a movable part. The method and apparatus comprise at least two resonators formed by coupled slow-wave structures, e.g. coupled spirals, and a movable target. The angular position of the target is representative of the angular position of the movable part. A change in the angular position of the target causes a change in electrodynamic parameters of the resonators. The change in the electrodynamic parameters is converted to a reading of angular position of the target with respect to the resonators. An electromagnetic field is excited in the resonators at a frequency at which electromagnetic parameters of the resonators depend upon the position of the target.

Abstract: A measurement technique based on a microwave near-field scanning probe is developed for non-contact measurement of dielectric constant of low-k films. The technique is non-destructive, non-invasive and can be used on both porous and non-porous dielectrics. The technique is based on measurement of resonant frequency shift of the near-field microwave resonator for a plurality of calibration samples vs. distance between the probe tip and the sample to construct a calibration curve. Probe resonance frequency shift measured for the sample under study vs. tip-sample separation is fitted into the calibration curve to extract the dielectric constant of the sample under study. The calibration permits obtaining a linear calibration curve in order to simplify the extraction of the dielectric constant of the sample under study.

Abstract: This invention is a method to determine the condition of rotating equipment, namely drive spindles, to enable the timely maintenance or replacement of same. The method uses an electrical signal from a vibration sensor mounted on part of the drive train to measure the level of vibration energy when the equipment is rotating under loaded and unloaded conditions. The relative vibration under the loaded and unloaded conditions is used as an indicator of equipment condition. Typically there is more vibration under load when the equipment is in good condition. When the level of vibration under the no-load condition matches or exceeds that seen under load, the equipment needs to be serviced or replaced.