In a load sensor detecting a magnitude of an external load applied in a direction parallel to a sheet shape of a sheet-shaped quartz crystal resonator, the load sensor comprising: a quartz crystal resonator layer including the sheet-shaped quartz crystal resonator and a pair of electrode portions on a pair of surfaces opposite to each other in a plate thickness direction of the quartz crystal resonator; and a pair of holding layers disposed to sandwich both sides of the sheet shape of the quartz crystal resonator layer and causing a displacement in substantially the same amount as the quartz crystal resonator layer when the external load is applied to the quartz crystal resonator layer, the holding layers and the quartz crystal resonator layer are made of materials having substantially equivalent rates of thermal expansion.

A physical quantity sensor includes: a supporting member; and a sensor element supported by the supporting member, in which the sensor element includes a vibrator element, a drive signal wiring disposed on the vibrator element, and a first detection signal terminal and a second detection signal terminal disposed on the vibrator element, the supporting member includes a substrate on which the sensor element is joined, and a first detection signal wiring and a second detection signal wiring disposed on the substrate, and the first detection signal wiring and the second detection signal wiring respectively include areas that extend along a second axis intersecting with the first axis and that intersect with the drive signal wiring in a plan view as seen in a direction in which the sensor element and the substrate overlap with each other.

A resonating measurement system having at least a microelectromechanical system (MEMS) and/or nanoelectromechanical system (NEMS) is provided, including an optomechanical device comprising at least one resonating element at at least one resonance frequency of fr, and at least one optical element having an optical index sensitive to displacement of the at least one resonating elementl; excitation circuitry configured to excite the at least one resonating element at at least at one operating frequency of fm; an injection device configured to inject a light beam, having an intensity modulated at frequency of f1=fm+f, in the optomechanical device; and a photodetection device configured to measure an intensity of a light beam transmitted from the optomechanical device, the intensity having at least one component at frequency of f.

An environmental condition may be measured with a sensor (10) including a wire (20) having an ultrasonic signal transmission characteristic that varies in response to the environmental condition by sensing ultrasonic energy propagated through the wire using multiple types of propagation, and separating an effect of temperature on the wire from an effect of strain on the wire using the sensed ultrasonic energy propagated through the wire using the multiple types of propagation. A positive feedback loop may be used to excite the wire such that strain in the wire is based upon a sensed resonant frequency, while a square wave with a controlled duty cycle may be used to excite the wire at multiple excitation frequencies. A phase matched cone (200, 210) may be used to couple ultrasonic energy between a waveguide wire (202, 212) and a transducer (204, 214).

An environmental condition may be measured with a sensor (10) including a wire (20) having an ultrasonic signal transmission characteristic that varies in response to the environmental condition by sensing ultrasonic energy propagated through the wire using multiple types of propagation, and separating an effect of temperature on the wire from an effect of strain on the wire using the sensed ultrasonic energy propagated through the wire using the multiple types of propagation. A positive feedback loop may be used to excite the wire such that strain in the wire is based upon a sensed resonant frequency, while a square wave with a controlled duty cycle may be used to excite the wire at multiple excitation frequencies. A phase matched cone (200, 210) may be used to couple ultrasonic energy between a waveguide wire (202, 212) and a transducer (204, 214).

The invention relates to a marker device and a tracking system for tracking the marker device, wherein the marker device comprises a rotationally oscillatable magnetic object and wherein the rotational oscillation is excitable by an external magnetic field, i.e. a magnetic field which is generated by a magnetic field providing unit 20, 31 that is located outside of the marker device. The rotational oscillation of the magnetic object induces a current in coils, wherein based on these induced currents the position and optionally also the orientation of the marker device is determined. This wireless kind of tracking can be carried out with relatively small marker devices, which can be placed, for instance, in a guidewire, the marker devices can be read out over a relatively large distance and it is possible to use a single marker device for six degrees of freedom localization.

Hundreds of thousands of concrete bridges and hundreds of billions of tons of concrete require characterization with time for corrosion. Accordingly, protocols for rapid testing and improved field characterization systems that automatically triangulate electrical resistivity and half-cell corrosion potential measurements would be beneficial allowing discrete/periodic mapping of a structure to be performed as well as addressing testing for asphalt covered concrete. Further, it is the low frequency impedance of rebar in concrete that correlates to corrosion state but these are normally time consuming vulnerable to noise. Hence, it would be beneficial to provide a means of making low frequency electrical resistivity measurements rapidly. Further, prior art techniques for electrical rebar measurements require electrical connection be made to the rebar which increases measurement complexity/disruption/repair/cost even when no corrosion is identified. Beneficially a method of determining the state of a rebar without electrical contact is taught.

An amplitude detecting method and a material tester are provided. As functional blocks of a program that is installed in a personal computer and is stored in a memory, a measurement noise eliminating part that eliminates measurement noise, a vibration noise eliminating part that eliminates vibration noise assumed to be caused by an inertial force according to a natural vibration according to reach of an impact of breakage or destruction of a test piece at the entire tester, an amplitude detecting part that detects the amplitude of a natural vibration superimposed in the data period used for evaluating material characteristics, and a display control part that controls display of an amplitude value of the natural vibration and a test result on the display device are included.

A method of measuring an axial force of a bolt may include fastening a joint using a fastener, receiving a vibration signal by a detector, transforming the received vibration signal into frequency domain data having a plurality of frames, analyzing the signal transformed into the frequency domain data, and predicting an axial force and indicating a predictive value thereof.

A method of measuring an axial force of a bolt may include fastening a joint using a fastener, receiving a vibration signal by a detector, transforming the received vibration signal into frequency domain data having a plurality of frames, analyzing the signal transformed into the frequency domain data, and predicting an axial force and indicating a predictive value thereof.