1390 results about "Strain sensor" patented technology

A cutting instrument including a metal blade has a recess formed therein and a semiconductor substrate affixed to the blade in the recess. The semiconductor substrate includes at least one sensor formed thereon. The sensor formed on the semiconductor substrate may comprise at least one or an array of a strain sensors, pressure sensors, nerve sensors, temperature sensors, density sensors, accelerometers, and gyroscopes. The cutting instrument may also further include a handle wherein the blade is affixed to the handle and the semiconductor substrate is electrically coupled to the handle. The handle may then be coupled, either physically or by wireless transmission, to a computer that is adapted to display information to a person using the cutting instrument based on signals generated by one or more of the sensors formed on the semiconductor substrate. The computer or handle may also be adapted to store data based on the signals generated by one or more of the sensors. A method of making said cutting instrument includes the steps of at least one sensor being formed on a semiconductor wafer and a layer of photoresist being applied on a top side of the semiconductor wafer according to a pattern that matches the defined shape of the semiconductor substrate. The portion of the semiconductor wafer not covered by the photoresist is removed and thereafter the photoresist is removed from the semiconductor wafer, thereby leaving the semiconductor substrate having a defined shape and at least one sensor formed thereon. The semiconductor substrate having a defined shape and at least one sensor formed thereon is then affixed to a metal blade in a recess formed in said blade.

A telemetry method and apparatus using pressure sensing elements remotely located from associated pick-up, and processing units for the sensing and monitoring of pressure within an environment. This includes remote pressure sensing apparatus incorporating a magnetically-driven resonator being hermetically-sealed within an encapsulating shell or diaphragm and associated new method of sensing pressure. The resonant structure of the magnetically-driven resonator is suitable for measuring quantities convertible to changes in mechanical stress or mass. The resonant structure can be integrated into pressure sensors, adsorbed mass sensors, strain sensors, and the like. The apparatus and method provide information by utilizing, or listening for, the residence frequency of the oscillating resonator. The resonant structure listening frequencies of greatest interest are those at the mechanical structure's fundamental or harmonic resonant frequency. The apparatus is operable within a wide range of environments for remote one-time, random, periodic, or continuous/on-going monitoring of a particular fluid environment. Applications include biomedical applications such as measuring intraocular pressure, blood pressure, and intracranial pressure sensing.

A touch sensing catheter having a strain sensor assembly that may resolve the magnitude and direction of a force exerted on a distal extremity of the catheter, the strain sensor assembly being substantially insensitive to bulk temperature changes. A deformable structure having a plurality of optical fibers associated therewith that are strained by the imposition of a contact force transferred thereto. The optical fibers cooperate with the deformable structure to effect variable gap interferometers, such as Fabry-Perot resonators, that vary in operative length when a force is exerted on the deformable structure. The strain sensor assembly is rendered insensitive to bulk temperature changes by matching the coefficient of thermal expansion of the deformable body with that of the optical fibers. The strain sensor assembly may also be configured to mitigate the effects of thermal gradients using various thermal isolation techniques.

An input apparatus includes a surface plate, an electrostatic capacitive sensor disposed under the surface plate, and a strain sensor disposed between the electrostatic capacitive sensor and the surface plate and fixed to the back surface of the surface plate. As a first input operation, when a finger is moved on an operation area of the surface plate, the movement position can be detected by the electrostatic capacitive sensor. As a second input operation, when the operation area is pressed down, the pressing force can be detected by the strain sensor. A series of the first input operation and the second input operation can be performed without leaving the finger from the operation area. Therefore, the input operation can be simply performed.

A strain sensor for measuring strain in a surface of an object includes an insulating flexible substrate, a first conductive contact, a second conductive contact and a piezoelectric nanowire. The insulating flexible substrate is coupled to the object. The first conductive contact and the second conductive contact are mounted on the insulating substrate. The piezoelectric nanowire is electrically coupled to the first conductive contact and the second conductive contact. The piezoelectric nanowire is subject to strain when the surface of the object is subject to strain, thereby creating a voltage differential therebetween. A trigger sensor includes a substrate, a piezoelectric nanowire and a conductive contact. The piezoelectric nanowire extends from the substrate. The conductive contact is disposed in relation to the piezoelectric nanowire so that a voltage differential between the substrate and the conductive contact when the substrate moves with the predetermined acceleration.

A strain sensing assembly implements thermal management and/or temperature measurement techniques to adequately mitigate against and compensate for temperature changes in optical fiber strain sensors of a distal end of a catheter. In one embodiment, the distal end of the catheter includes an end effector such as an ablation head that introduces significant thermal temperature changes proximate the distal end of the catheter. In one embodiment, a plurality of temperature sensors is utilized for accurate determination of each of a plurality of optical fiber strain sensors. In other embodiments, a single temperature sensor may be utilized by implementing thermal management techniques that adequately reduce temperature differences between the single temperature sensor and the plurality of optical fiber strain sensors.

An electric cable includes a strain sensor longitudinally extending along the cable and including a strain optical fibre arranged within a bending neutral region surrounding and including a bending neutral longitudinal axis of the electric cable, and at least two longitudinal structural elements, at least one of the at least two longitudinal structural elements being a core including an electrical conductor, wherein the strain sensor is embedded in a strain-transferring filler mechanically coupling at least one of the at least two longitudinal structural elements with the strain sensor. With the disclosed cable construction, the strain experienced by the at least one of the at least two longitudinal structural elements is transferred to the strain sensor at least in a strained condition. In the preferred embodiments, the electric cable is a heavy-duty cable.

A multi-force sensing instrument includes a tool that has a tool shaft having a distal end and a proximal end, a strain sensor arranged at a first position along the tool shaft, at least one of a second strain sensor or a torque-force sensor arranged at a second position along the tool shaft, the second position being more towards the proximal end of the tool shaft than the first position, and a signal processor configured to communicate with the strain sensor and the at least one of the second strain sensor or the torque-force sensor to receive detection signals therefrom. The signal processor is configured to process the signals to determine a magnitude and position of a lateral component of a force applied to the tool shaft when the position of the applied force is between the first and second positions.

The invention discloses super-far distributed fiber Raman and Brillouin photon sensors; by using the stimulated Raman scattering effect of fiber, the self Raman scattering effect of fiber, the Brillouin scattering effect of fiber and the light time-field reflection principle, distributed fiber Raman photon temperature sensors, distributed fiber Brillouin photon strain sensors and distributed fiber Raman amplifier are integrated together. Fiber consumption is overcome by using the gain of amplifier, and strengths of self Raman scattering light and Brillouin scattering light in fiber is enhanced, the signal to noise ratio of the system of distributed fiber Raman photon sensor and distributed fiber Brillouin photon strain sensor is enhanced, meanwhile, the transmission distances of distributed fiber Raman photon sensor and distributed fiber Brillouin photon strain sensor are increased, finally, the temperature and stress measuring accuracy is enhanced.

A printed stretchable strain sensor comprises a seamless elastomeric body and a strain-sensitive conductive structure embedded in the seamless elastomeric body. The strain-sensitive conductive structure comprises one or more conductive filaments arranged in a continuous pattern. A method of printing a stretchable strain sensor comprises depositing one or more conductive filaments in a predetermined continuous pattern into or onto a support matrix. After the depositing, the support matrix is cured to embed a strain-sensitive conductive structure in a seamless elastomeric body.

A method is described using optical fiber technology to measure the vibration characteristics of long slender structures subjected to dynamic disturbances imposed by water or wind generated loads. The method is based on making bending strain measurements at selected locations along the length of long slender structures such as marine risers or large ropes using fiber optics technology including Optical Time Domain Reflectometry and Bragg diffraction gratings. Engineering interpretation of information obtained from bending strains determines the vibration characteristics including frequency, amplitude, and wave length. Maximum bending strain measurements assess pending structural damage. One application is measurement of vortex induced vibrations (VIV) response of marine risers. The fiber optics based method is also applicable to the measurement of the bending characteristics of spoolable pipe using plastic optical fibers which can be interpreted to assess the pipe structural integrity and to prevent lock-up during deployment into a small diameter annulus.

An improved method of sensing strain allows measurements of stress, torque, vibration and other loads imposed on a body without physical contact between the body/sensor and the monitoring equipment. An induction loop is at least partially comprised of a magnetostrictive material with a non-linear current-voltage relationship. An excitation device such as a coil is used to induce an AC response in the sensor. The non-linear response to the induced current is received by a sensing device such as a sensing coil, and the output thereof is filtered. The excitation device and sensing device are located in operative proximity to the sensor, but need not be in contact therewith, allowing easy measurement in small spaces, under harsh conditions, or of moving bodies such as drive shafts. The non-linear response of the sensor induces easily detectable harmonics of the base frequency of excitation. These harmonics may advantageously be measured as well.

A bolt with a function of measuring strain, comprising a Wheatstone bridge circuit comprising a strain sensor and a dummy resistor, a translate circuit that amplifies a signal from the Wheatstone bridge circuit to convert the same into a digital signal, a transmitting circuit that transmits the digital signal outside the bolt, and a power circuit, by which electromagnetic wave energy received from outside the bolt is supplied as a power source for at least any one of the circuits.

The invention discloses a real-time bridge load identification method based on an influence matrix. The method includes: according to bridge monitoring aims and precision requirements, setting displacement, angle and strain sensors on a bridge; according to bridge structural form and load features, equaling bridge load into a feature load combination; establishing a finite element analysis model for the bridge, and separately calculating measured values of each sensor caused by each unit feature load; combining the measured values of the sensors caused by the unit feature loads into the influence matrix; according to the measured values of the sensors, calculating the magnitude of the feature load, as current actual load of the bridge; and calculating deformation and stress mechanical parameters of a concerned position of the bridge, and evaluating safety state of the bridge according to the mechanical parameters. The method is applicable to various types of identifiable or equivalent basic loads and various type of measurement information, including absolute or relative displacement, absolute or relative angle, strain, internal force, external force and the like.

An apparatus including a strain sensor configured to sense strain in a connecting part between a first part and a second part of a headset, and a circuitry earpiece configured to cause a change in the state of the headset in accordance with the sensed strain. A corresponding method.

The invention relates to a fiber grating strain and temperature simultaneously measuring sensor. A fiber grating strain sensor is formed by utilizing a second stainless steel pipe to package bare fiber grating, a fiber grating temperature sensor is formed by utilizing a metal pipe to package bare fiber grating, and the fiber grating strain sensor and the fiber grating temperature sensor are packaged in parallel in a first stainless steel pipe by adopting epoxide resin. When the sensor is arranged on an engineering structure, the first stainless steel pipe produces the distortion and transmits the temperature and the strain of the structure to the fiber grating strain sensor at the inner part and the fiber grating temperature sensor without strain influence through the epoxide resin, the measuring value of the strain sensor is compensated by the temperature sensor so as to achieve the simultaneous measurement of the strain and the temperature of the structure.

An orthopaedic device for generating one or more strain signals representative of the strain in a bone in response to a force applied to the bone. The device includes an encircling member (11) for encircling the bone of a subject and a sensor member (13) connected thereto, the sensor member including a strain sensor (14). In a preferred embodiment the strain sensor comprises one or more bridging members configured to break when subjected to a particular strain.

A mechanical quantity measuring apparatus is provided which can make highly precise measurements and is not easily affected by noise even when it is supplied an electricity through electromagnetic induction or microwaves. At least a strain sensor and an amplifier, an analog/digital converter, a rectification/detection/modulation-demodulation circuit, and a communication control circuit are formed in one and the same silicon substrate. Or, the silicon substrate is also formed at its surface with a dummy resistor which has its longitudinal direction set in a particular crystal orientation and which, together with the strain sensor, forms a Wheatstone bridge. With this arrangement, even when a current flowing through the sensor is reduced, measured data is prevented from being buried in noise, allowing the sensor to operate on a small power and to measure a mechanical quantity with high precision even when it is supplied electricity through electromagnetic induction or microwaves.

An actuator arm assembly has an actuator arm and an actuator for moving the actuator arm whereby the arm assembly experiences vibrations. The actuator has a body with a recess formed therein, and a strain sensor is fitted essentially inside the recess such that the sensor generates signals correlated to the vibrations. This arrangement produces a high gain boost from the strain based sensor, making an amplifier circuit unnecessary. The sensor signals are used to damp the vibrations.

The invention discloses a full-automatic high-pressure container gas circular charging and discharging fatigue test system which not only can realize the full-automatic control of the high-pressure gas circular charging and discharging fatigue test but also can carry out the on-line automatic detection to the fatigue condition of the high-pressure container. The automatic control of the circular charging and discharging is realized through the dynamic response signals of a temperature sensor arranged inside the tested container, the dynamic response signals of each pressure sensor on the high-pressure pipelines and switching of solenoid valves controlled by the control strategy. The gas medium in the circular charging and discharging process can be recycled after the pressurizing by a pressure-releasing receiving tank and a gas compressor so as to avoid the gas waste and environment contamination. The dynamic fatigue states of the high-pressure container in the circular charging and discharging process are acquired through the changing of response signals of a hydrogen sensor arranged in a sealed bin of the tested container and the response signals of a strain sensor stuck to the surface of the tested container; and when the released hydrogen concentration reaches the set value or the strain of the container material exceeds the set value in the charging and discharging process, the fatigue test system is closed automatically.

A measurement module that measures force being applied to a man-powered machine includes: a strain sensor that detects strain of a crank of the bicycle configured to transmit force being applied from a user through the crank and one front gear selected among one or more front gears; an MM magnetic sensor that detects the crank passing through a predetermined position; and an MM control part. The MM control part calculates a rotation angle of the crank based on an elapsed time from a time the crank passes through the predetermined position that the sensor has detected, calculates force applied to the crank based on a strain amount of the crank that the strain sensor has detected, associates the rotation angle with the force applied to the crank to calculate distribution of the force applied from the user.

A high sensitivity strain sensor that utilizes a micro-scale cavity built in a multi-layer structure, with a pair of interdigitalized capacitor incorporated on one of the layers, is described in this document. The device's capacitance changes produced by unattended deformations of the cavity can be used to measure the associated strain without using any movable electrodes. The sensor can be remotely energized from a radio frequency wave sent by a reader antenna to construct a battery-free wireless instrument. Changes on the sensor's resonant frequency are remotely detected so that a strain level is measured from fluctuations in the received signal. This detection method provides a simple, reliable and sensitive technique to measure small strain changes down to the pico-scale. Materials with a highly strain-dependant permittivity are integrated in the sensor to enhance its sensitivity. The proposed sensor consists of a simple planar structure. It can be used as the main component on low-cost, accurate and highly stable strain measuring instruments capable of monitoring very small strain levels. Furthermore, the sensor is passive, may be operated wirelessly, and can, thus, be used for remote long-term embedded strain detection.

An apparatus for measuring tension in guy wire systems wherein the lower end of the guy wire has a thimble adjoined by a connection pin to a yoke or clevis of a turnbuckle shackle bolt connected to an earth anchor. A block assembly is removably received beneath the clevis and a thimble-engaging jaw assembly is removably received on the guy wire above the clevis. The block assembly and jaw assembly are connected at one end by a threaded rod assembly that includes a strain sensor connected with an indicator device, and by a threaded rod at their opposed end. The jaw assembly is drawn downward by adjusting nuts on the threaded rods beneath the block assembly to engage the thimble and move it downward transferring the tension to the threaded rod and threaded rod assembly which is sensed by the strain sensor and indicated by the indicator device.

To provide a sensor equipped wheel support bearing assembly, in which the sensor for detecting the load can be snugly and neatly installed in an automotive vehicle, the load acting on the vehicle wheel can be detected with high sensitivity and the cost of manufacture can be reduced during a mass production. The sensor unit 21 is mounted on an outer member 1, which is a stationary member of the wheel support bearing assembly. The sensor unit 21 includes a sensor mounting member 22 and at least one or more strain sensors 23 fitted to the sensor mounting member 22. The outer member 1 includes a knuckle contact portion contactable with a knuckle 16 and is provided with a cutout portion 17 defined in a portion of the knuckle contact portion 1a.

The invention relates to a method for monitoring the circumferential strain of a casing by applying optical-fiber grating sensors, which mainly solves the problem that an electric-resistance strain gauge adopted of the current technology for monitoring the circumferential deformation of the casing is easy to be affected by electromagnetism in a well and corrosion, thus causing a measured circumferential strain signal of the casing to be inaccurate. The method is characterized in that: the optical-fiber grating sensors are arranged outside the casing along the circumferential direction of the casing, wherein, a plurality of optical-fiber grating sensors are evenly arranged around the casing; sections of adjacent intervals form a certain angle; an optical-fiber temperature compensating sensor is arranged in a position at a corresponding distance away from the group of sensors; the optical-fiber grating sensors are applied to monitoring the circumferential deformation and stress status of the casing within certain ranges; meanwhile, the temperature compensating sensor is applied to serving the temperature compensation and temperature monitoring in the well of the strain sensor; the sensors transmit underground signals to the ground by a transmission optical cable; and the signals can be transformed into the circumferential strain information of the casing after a demodulation instrument obtains the signals and carries out secondary treatment. The method is characterized by not being affected by the underground electromagnetism.

The present invention provides microcantilever hotplate devices which incorporate temperature compensating strain sensors. The microcantilever hotplate devices of the present invention comprise microcantilevers having temperature compensating strain sensors and resistive heaters. The present invention also provides methods for using a microcantilever hotplate for temperature compensated surface stress measurements, chemical/biochemical sensing, measuring various properties of compounds adhered to the microcantilever hotplate surface, or for temperature compensated deflection measurements.

A method and system for rendering the shape of a multi-core optical fiber or multi-fiber bundle in three-dimensional space in real time based on measured fiber strain data. Three optical fiber cores arc arranged in parallel at 120° intervals about a central axis. A series of longitudinally co-located strain sensor triplets, typically fiber Bragg gratings, are positioned along the length of each fiber at known intervals. A tunable laser interrogates the sensors to detect strain on the fiber cores. Software determines the strain magnitude (ΔL/L) for each fiber at a given triplet, but then applies beam theory to calculate curvature, beading angle and torsion of the fiber bundle, and from there it determines the shape of the fiber in s Cartesian coordinate system by solving a series of ordinary differential equations expanded from the Frenet-Serrat equations. This approach eliminates the need for computationally time-intensive curve-tilting and allows the three-dimensional shape of the optical fiber assembly to be displayed in real-time.

A torque sensing arrangement has a set of strain sensors, such as strain gauges, mounted to an adapter that can be mounted to a chain ring of the crank set of a bicycle wheel. The adapter may have an annular body that can be used to retrofit the original crank set of a bicycle to have torque sensing components without having to replace the chain rings or the crank arm of the crank set. Together with angular velocity measurements, the measurements of the strain sensors may be used to calculate the amount of work or power exerted by the cyclist to propel the bicycle.

The invention relates to a test method for bonding stress between a fiber reinforced plastic(FRP) bar and concrete, comprising the following steps that: step 1, casting a bonding specimen (7) of the FPR bar and the fiber bar concrete, providing a single-mode fiber (b) as a strain sensor to work with the FRP bar for the production molding of a FRP bar-fiber bar (graph 1), then casting the FRP bar-fiber bar central drawing sample, simultaneously casting three concrete cubic specimens for detecting the intensity of the concrete, wherein, the length, width and height of the concrete cubic specimen are all 150 mm; step 2, maintaining the bonding specimen of the FPR bar and the fiber bar concrete for 28 days according to the < concrete intensity standards >. The test method provided by the invention is accurate and reliable.

The invention discloses a random recognition method for bridge floor moving vehicle loads. The method comprises the following steps that (1) raster sensors, strain sensors and acceleration sensors are arranged on a bridge floor to obtain running speeds of moving vehicles and the dynamic strain and acceleration responses of a bridge under the action of the moving vehicle loads; (2) an accurate structural finite element model is established for a bridge structure, model condensation is carried out, and the freedom degree of the bridge model after the model condensation is made to be matched with dynamic strain signal measuring positions; (3) the deterministic components of bridge random dynamic displacement, speed and acceleration are obtained by utilizing a KL decomposition technique on the basis of actual measurement dynamic strain response samples; (4) the deterministic components random moving vehicle loads on the bridge floor are recognized by directly adopting a sample matrix inversion and a Tikhonov regularization method; (5) the statistical properties, average time history and variance, of the random moving vehicle loads are obtained.