589results about "Force measurement by measuring frquency variations" patented technology

An acoustic-based system, such as a touchscreen system, is provided. The system comprises an acoustic substrate and an acoustic transducer operably coupled to the substrate. The transducer exhibits a higher order odd resonant frequency that is equal to the operating frequency of the system. As a result of using the higher resonant frequency that is substantially equal to the operating frequency, the thickness of the transducer can be increased, and thus made more durable.

An electrical pressure sensor is provided with a method for measuring pressure applied to a sensor surface. The method provides an electrical pressure sensor including a sealed chamber with a top surface, first electrode, second electrode, an elastic polymer medium, and metallic nanoparticles distributed in the elastic polymer medium. When the top surface of the sensor is deformed in response to an applied pressure, the elastic polymer medium is compressed. In response to decreasing the metallic nanoparticle-to-metallic nanoparticle mean distance between metallic nanoparticles, the electrical resistance is decreased between the first and second electrodes through the elastic polymer medium.

Hundreds of thousands of concrete bridges, buildings etc. and hundreds of billions of tons of concrete require characterization throughout the process from manufacture to pouring and curing and on throughout service life. The characterization may relate to initial concrete properties, projected concrete properties, framework removal, corrosion, failure etc. Accordingly, a variety of measurements such as water content, electrical resistivity, and half-cell corrosion potential for example would be beneficially implemented as easy to use field test equipment or embedded sensors allowing lifetime monitoring to be performed rather than discrete assessments when issues become evident.

A sensor system includes a touch screen and a force sensor. The touch screen has a first and second surface and detects a first surface touch and converts it to data indicative of an X, Y coordinate position upon the touch screen first surface. The force sensor contacts the touch screen second surface and substantially extends around the perimeter of the touch screen second surface. The force sensor measures the force exerted by the first surface touch in the form of force data.

An electrically conductive composite material includes metallic nanostrands distributed throughout a matrix constructed of a polymer, ceramic, or elastomer. The nanostrands may have an average diameter under four microns and an average aspect ratio over ten-to-one. Larger fibers may also be included to enhance electrical conductivity or other properties. The nanostrands and/or fibers may be magnetically oriented to enhance electrical conductivity along one direction. A pressure sensor may be formed by utilizing an elastomer for the matrix. Electrical conductivity through the composite material varies in proportion to deflection of the elastomer. A composite material may be applied to a surface as an electrically conductive paint. Composite materials may be made by cutting a blank of the nanostrands to the desired shape, inserting the matrix, and curing the matrix. Alternatively, a suspension agent may first be used to dispose powdered nanostrands in the desired shape.

This invention relates to impact sports, and to articles of clothing and for detection systems used to monitor and registering the intensity, location and sources of impacts in contact sports such as boxing, martial arts, fencing, and so forth.

The present invention relates to a ground stress measuring method which comprises the following procedures: 1) the occurrence of joint and faultage are determined; the nearest sequent subjoint and fissure in the same sequence are drawn on a stereographic projection drawing; 2) a terrane lay uses the strike line as a rotating axis and rotates to the horizontal position towards the dip direction; the rotary angle is equal to a dip angle of the lay, and the strike line of the joint and fissure winding lay rotates to the horizontal state to find a conjugated X-shaped joint; then the conjugated X-shaped joint and lay in the horizontal state rotate to the original state; three directions of the ground stress are determined on the stereographic projection drawing; 3) samples are drilled along three directions of the ground stress and 5 to 7 samples are drilled along each direction; 4) the acoustic emission experiment of a rock sample is done indoors to have a Db4 small wave analysis on the acoustic emission signals of rock, thereby determining the acoustic emission Kaiser point of rock; the size of the ground stress is determined according to the acoustic emission Kaiser point of rock. The invention is small in sample quantity, low in cost, rapid in measuring progress of the ground stress, and accordingly more convenient and rapid in measurement of the ground stress.

A microfluidic embedded nanoelectromechanical system (NEMs) force sensor provides an electrical readout. The force sensor contains a deformable member that is integrated with a strain sensor. The strain sensor converts a deformation of the deformable member into an electrical signal. A microfluidic channel encapsulates the force sensor, controls a fluidic environment around the force sensor, and improves the read out. In addition, a microfluidic embedded vacuum insulated biocalorimeter is provided. A calorimeter chamber contains a parylene membrane. Both sides of the chamber are under vacuum during measurement of a sample. A microfluidic cannel (built from parylene) is used to deliver a sample to the chamber. A thermopile, used as a thermometer is located between two layers of parylene.

An impact sensor includes a piezoelectric transducer operatively connected to a chromic device. The chromic device includes a chromic material that changes from a first color state to a second color state in response to electric power generated by the piezoelectric transducer when exposed to a given level of impact force. The chromic material is bistable so that the chromic material remains in the second color state for a significant amount of time. An impact force to which the sensor has been subjected may be quantified by observing the chromic device. In one embodiment, the chromic material is an electrochromic material, such as a viologen, that changes through a color gradient of light transmission states from the first color state to the second color state. A printed color gradient may be used to aid in quantifying the impact force. In another embodiment, the chromic device includes a thermochromic material.

A mass sensor includes a diaphragm, a sensing plate having a piezoelectric element arranged on at least a part of at least one surface joining respective sides, a connecting plate sandwiched by the diaphragm and the sensing plate, wherein the diaphragm, the sensing plate, the piezoelectric element, and the connecting plate form a resonating portion. The connecting plate is bridged across the side surfaces of a concave portion formed in a sensor substrate, and the sensing plate is joined to at least the bottom portion of the concave portion. Change in the mass of the diaphragm is measured by measuring change in the resonant frequencies of the resonating portion accompanying the change in the mass of the diaphragm. The mass sensor enables the easy and accurate measurement of a minute mass of a nanogram order including microorganisms such as bacteria and viruses, or chemical substances, or the thickness of vapor-deposited films.

The invention discloses a structure of two resonant micro pressure sensor chips and a method of manufacturing the same. The structure of two resonant micro pressure sensor chips comprises a pressure inductive diaphragm with one or two rigid cores, a double-end clamped support beam and a cover plate 3. Under the function of fluid pressure, the diaphragm with rigid cores deforms to exert the double-end clamped support beams on the surface of the diaphragm to change resonant frequency upon the function of axial stress. Fluid pressure can be reflected by measuring the change in the resonant frequency of the double-end clamped support beam. The silicon resonant micro pressure sensor of the invention has higher signal-to-noise ratio, resolution, sensitivity and measurement precision and the output of the invention is the frequency signal.

The invention discloses a method and device for testing a geo-stress of a deep soft rock. The device comprises a connecting rod; two three-direction pressure boxes are adjacently fixed on the connecting rod; the three-direction pressure box is provided with three vertical working surfaces; a direction cosine of any two working faces among the two three-direction pressure boxes is not 1; a device for measuring a normal pressure stress is mounted on each working face of the two three-direction pressure boxes; and the device is connected with a reading instrument outside a drilling hole through a data wire. A geo-stress testing method comprises the following steps of: sending the two three-direction pressure boxes to a test point after drilling; grouting the drilling hole and sealing the drilling hole after the drilling hole is entirely filled; and after slurry is solidified, substituting six pressure data measured by the two three-direction pressure boxes into a geo-stress testing principle formula after the data is stable, so as to obtain the geo-stress at the test position. With the adoption of the method, a stress value inside surrounding rocks can be directly observed, and observation data can be obtained for a long time. Therefore, the method and device provided by the invention is good for researches of coal deep rock geo-stress and the stability of a surrounding rock.

A dynamic quantity sensor includes a force receiving portion, a first movable portion that rotates in a first rotational direction around a first rotational axis according to dynamic quantity in a first direction that the force receiving portion receives, and rotates in the first rotational direction around the first rotational axis according to dynamic quantity in a second direction different from the first direction that the force receiving portion receives; and a second movable portion that rotates in a second rotational direction around a second rotational axis according to the dynamic quantity in the first direction that the force receiving portion receives, and rotates in an opposite direction to the second rotational direction around the second rotational axis according to the dynamic quantity in the second direction that the force receiving portion receives.

The invention is a random no-wear power detection technology about the stress state of anchor arm and there is installing a exciting force fasten instrument on the open end of the anchor fastened on the rock mass (coal) anchor arm anchor wire and on the open end of the anchor arm anchor wire installs an acceleration transducer connecting with the intelligent dynamic measurement equipment and make the anchor arm generated a lateral vibration by forcing to the exciting force fasten instrument and adopts the acceleration signal by the acceleration transducer and then transfer to the intelligent dynamic measurement equipment and the intelligent dynamic measurement equipment transfers the acceleration signal into the digital signal and stores it at last inputs the adopted data to the computer for computing and treating so it completes the detection of the inherent stress at the time of completed the initial installment and the detection of load at the sated of work and the monitor of forcing whole process, non-breakage, exhaustive, it can make no-wear power detection for random one anchor arm and the operation is easy and the use is convenience and speed and it is easy to carry and the effect is good and it has the extensive practicability.

The invention discloses a force sensor based on micro-nano combined structure, comprising bridge beam, mass block, substrate and plural electrodes arranged on the substrate, where there is an insulating layer between the electrodes and the substrate, the two ends of the bridge beam are fixed on the electrodes, the mass block is fixed in the middle of the bridge beam, suspending in midair, and the bridge beam is a semiconductor oxide nano tape and the force sensor also comprises a resonance frequency detection circuit for measuring the resonance frequency of the bridge beam. The force sensor is combined of micro-electromechanical (MEM) sensor and nano material, adopts the semiconductor oxide nano tape as the bridge beam and the structure of the force sensor is controllable and no-defect and besides, the nano tape has excellent flexibility and can make larger deformation under the force action, and these advantages can improve the resolution and accuracy of the force sensor. It makes more measuring methods able to be selected for the force sensor.

The invention discloses a silicon micro resonant type pressure sensor and a manufacturing method of the silicon micro resonant type pressure sensor, relates to a pressure sensor and provides a silicon micro resonant type pressure sensor which is based on synovial membrane damping and a double pressure membrane structure, and a manufacturing method of the pressure sensor. The pressure sensor comprises a pressure sensitive layer, a resonant structure layer, a vacuum encapsulation blocking layer and lead electrodes, wherein the upper part of the border frame of the pressure sensitive layer is connected with the lower part of the border frame of a resonant structure layer; the upper border frame of the pressure sensitive layer is internally provided with two pressure membranes and is provided with two cavities for holding parallel silicon islands; the top ends of the silicon islands are connected with a first transmission beam and a second transmission beam on the resonant structure layer; channels are formed between the two cavities, so that the first resonant beam, the second resonant beam, a first mass block and a second mass block on the resonant structure layer have space for free vibration; the upper part of the border frame of the resonant structure layer is connected with a lower border frame of the vacuum encapsulating blocking layer; a cavity is formed inside a lower border frame of the blocking layer; lead holes are formed on the vacuum encapsulating blocking layer; and the lead electrodes are connected with the resonant structure layer through the lead holes.

The invention provides a resonant type pressure sensor. The sensor comprises a sensor body, a pressure-sensitive film is formed at the bottom of the sensor body, a first resonator and a second resonator are formed on the pressure-sensitive film, the two resonators have the same intrinsic frequency, sensitivities, to the pressure P acting on the pressure-sensitive film, of the two resonators are equal, the first resonator is located in the center of the pressure-sensitive film, and the second resonator is located on the edge of the pressure-sensitive film. According to the resonant type pressure sensor, the two resonators are adopted, pressure characteristics of the sensor are represented by means of differential frequency output, influences of temperature factors are reduced, and pressure sensitivity and linearity of the sensor are improved. Temperature characteristics of the sensor are represented by means of sum frequency output for sensor temperature compensation, and the use temperature range of the sensor is widened.

In a force-measuring cell with a deformable body and with at least one strain gauge which has a strain-sensitive electrical resistor track arranged on a polymer carrier substrate, the strain gauge is bonded to the deformable body by an adhesive layer of an inorganic-organic hybrid polymer. For the bonding of the strain gauge to the deformable body, an adhesive compound having an inorganic-organic hybrid polymer in solution is applied to the deformable body, whereupon the strain gauge is placed on the hybrid polymer layer, and the adhesive layer is subsequently hardened at a temperature between 80° C. and 130° C. For the hardening of the adhesive layer, the deformable body with the strain gauge is exposed to the increased temperature for a time period between a half hour and three hours.