The invention relates to a vibrating bridge for a vibrating-wire sensor, comprising opposing clamping points for connecting the vibrating bridge to the vibrating-wire sensor and comprising multiple vibrators which are provided between the clamping points and which are mechanically connected to the securing points and can be tensioned via the securing points, wherein one of the vibrators is free of a vibration exciter or vibration detector, and another vibrator is provided with a vibration exciter.

A stress estimation method for a machine structure according to an embodiment is provided with a calculation step of calculating a relationship between the stress generated at the evaluation target position and a physical quantity including a sound pressure or vibration generated at a detection position different from the evaluation target position during vibration of the machine structure. The stress estimation method for a machine structure is provided with a detection step of detecting the physical quantity generated at the detection position during operation of the machine structure. The stress estimation method for a machine structure is provided with an estimation step of estimating the stress generated at the evaluation target position during operation of the machine structure on the basis of the relationship calculated in the calculation step and the physical quantity detected in the detection step.

A resonant sensor includes a proof body having a first and a second interface that can each come into contact with an external mechanical structure; two sensitive zones arranged between these two interfaces; a sensitive zone formed by a plate embedded in a frame secured mechanically to the interfaces, the plate able to resonate under the effect of local mechanical excitations produced at particular points by excitation transducers bearing the plate at several resonant frequencies, sensors picking up the resonant signals produced at the particular points, measurement means measuring the resonant frequency shifts of signals which are linear combinations of the resonant signals picked up, the shifts being a function of mechanical stresses induced by the forces and transmitted to the plate by the frame, the components of the torque of forces being determined from the resonant frequency shifts measured on the plates of the sensitive zones.

Devices, systems, and methods of the present disclosure are directed to accurate and non-invasive assessments of anatomic vessels (e.g., the internal jugular vein (IJV)) of vertebrates. For example, a piezoelectric crystal may generate a signal and receive a pulse echo of the signal along an axis extending through the piezoelectric crystal and an anatomic vessel. A force sensor disposed relative to the piezoelectric crystal may measure a force exerted (e.g., along skin of the vertebrate) on the anatomic vessel along the axis. The pulse echo received by the piezoelectric crystal and the force measured by the force sensor may, in combination, non-invasively and accurately determine a force response of the anatomic vessel. In turn, the force response may be probative of any one or more of a variety of different characteristics of the anatomic vessel including, for example, location of the anatomic vessel and pressure of the anatomic vessel.

Resonating sensors for use in high-pressure and high-temperature environments are provided. In one embodiment, an apparatus includes a sensor with a double-ended tuning fork piezoelectric resonator that includes a first tine and a second tine. These tines are spaced apart from one another so as to form a slot between the first and second tines. The width of the slot from the first tine to the second tine varies along the lengths of the first and second tines. Various other resonators, devices, systems, and methods are also disclosed.

An integrated circuit (IC) chip includes a substrate of a piezo-electric material having a first resistivity coefficient associated with a first direction that is longitudinal to a first crystal axis and a second resistivity coefficient associated with a second direction that is transverse to the first crystal axis. The first and second resistivity coefficients have opposite signs. The IC chip also includes a first stress sensing element formed in the substrate and coupled to pass a first current therethrough. The first stress sensing element includes a first resistor aligned such that the major direction of current flow through the first resistor is in the first direction and a second resistor coupled in series with the first resistor and aligned such that the major direction of current flow through the second resistor is in the second direction. A ratio of the resistance of the second resistor to the resistance of the first resistor is equal to a value ?, where ? is equal to the ratio of the first resistivity coefficient to the second resistivity coefficient.

Arrays of resonator sensors include an active wafer array comprising a plurality of active wafers, a first end cap array coupled to a first side of the active wafer array, and a second end cap array coupled to a second side of the active wafer array. Thickness shear mode resonator sensors may include an active wafer coupled to a first end cap and a second end cap. Methods of forming a plurality of resonator sensors include forming a plurality of active wafer locations and separating the active wafer locations to form a plurality of discrete resonator sensors. Thickness shear mode resonator sensors may be produced by such methods.

A mirror driving device is provided. A pair of piezoelectric actuator units are disposed at both sides of a mirror unit so as to sandwich the mirror unit, and each piezoelectric actuator unit is connected with an end portion of the mirror unit through a linking unit. The linking unit has a structure including one or more plate-shaped members whose longitudinal direction is a direction perpendicular to a rotation axis, and functions as a plate-shaped hinge unit in which a plate-shaped member is deformed so as to be deflected in the thickness direction by the drive of the piezoelectric actuator unit. The linking unit is provided with a sensor unit that detects the stress to be generated in the linking unit during the rotational drive of the mirror unit by a resonant vibration.

A piezoelectric sensor assembly for measuring a force quantity on a structure includes at least one piezoelectric sensor, each including an element and two electrodes each projecting outward from the element. An electronic processor of the assembly is configured to receive data from the sensor, wherein the data includes a voltage with a magnitude that is indicative of a dynamic load (i.e., amplitude modulation mode) placed upon the structure. The processor may be configured to interrogate the piezoelectric sensor for its resonant frequency change which is indicative of the load applied to the structure at low operation frequency and to which the piezoelectric sensor would not otherwise respond well. The dual mode operation of the piezoelectric sensor extends the frequency range of the strain measurement from the dynamic range to static or quasi-static range.

An actuator unit includes an actuator configured to cause a vibration by a vibrated member when a force is applied to the vibrated member and a first sensor configured to generate a first detection signal indicating a first relationship of a first physical quantity varying with time. The first physical quantity is related to the vibration of the vibrated member, a variation cycle of the first physical quantity changes based on a magnitude of the force applied to the vibrated member. The actuator unit also includes a processing circuit configured to process the first detection signal, extract a parameter indicative of the variation cycle of the first physical quantity, and estimate the magnitude of the force applied to the vibrated member based on the parameter.