106 results about "Strainmeter" patented technology

The invention relates to the technical field of bearing testing, in particular to a bearing integrated dynamic performance test device and method. The bearing integrated dynamic performance test device comprises a drive system, a transmission system, a measurement and control system, an environmental simulation system and a mechanical body structure. A motor is adopted by the drive system for driving. The measurement and control system controls the rotation speed of the motor. The transmission system is in a belt transmission mode or a coupler transmission mode. The measurement and control system is provided with a force sensor, a strainmeter, an eddy current transducer, a rotation speed sensor, a laser displacement sensor, a temperature sensor, a magnetic oil residue sensor, a pressure sensor, a flow sensor, an oil temperature sensor, an acceleration sensor and other related sensors used for bearing testing. The control system is driven in a servo mode, and is composed of a frequency converter, a hydraulic solenoid valve, a heating controller, a flow control device and a pressure control device. The environmental simulation system is adopted for simulating a real bearing testing working condition, and the performance and service life testing of the real bearing testing working condition is achieved.

A multiaxial force/torque sensor assembly and method for assembling such a sensor assembly are disclosed. The sensor assembly includes a set of at least two sensors each being made of strain gauges, which are each arranged at a definite angle and distance relative to each other and which are each fixed to a transducer body, which is mechanical contact with a printed circuit board. The printed circuit board includes clearances for each strain gauge as well as associated electronic components and wiring located on the remaining area of the printed circuit board which will monitor compressive and tensile stresses in the measurement directions of the sensors. The method includes positioning the strain gauges on the plane measurement surface of a transducer body in a definite arrangement; fixing the strain gauges to the transducer body by means of adhesives, and connecting the strain gauges to respective conductors by means of electrically bonding.

A medical probe, including a flexible insertion tube, having a distal end for insertion into a body cavity of a patient and which is configured to be brought into contact with tissue in the body cavity. The probe further includes a sensor tube of an elastic material, contained inside the distal end of the insertion tube and configured to deform in response to forces exerted by the tissue on the distal end. The probe also includes a plurality of strain gauges fixedly attached to a surface of the sensor tube at different, respective locations and configured to generate respective signals in response to deformations of the sensor tube.

A load sensor hardly causing error in weight measurement even when the environmental temperature of the load sensor varies, and a seat weight measuring apparatus using the load sensor. The sensor includes a plurality of strain gauges form a bridge circuit. The strain gauges forming the bridge circuit are attached to the front and back surfaces of a base plate at substantially the same location. Portions of a flexible substrate, on which the strain gauges are formed, are folded and adhered to the back of the sensor plate with adhesive. The bridge circuit formed by the strain gauges compensates for the variation in resistance among the strain gauges generated due to the temperature distribution of the base plate, resulting in little or no variation in output.

A printed circuit board (PCB) having an integrated strain gage. In one embodiment, a PCB includes a component footprint suitable for mounting an electronic component. A strain gage is integrated into the PCB in a location under the component footprint. The strain gage includes at least one electrical conductor that is accessible for resistance measurements.

The invention relates to a water and soil pressure monitoring rod for a shield tunnel, and the rod comprises a pressure monitoring rod body. The pressure monitoring rod body comprises a cylindrical rod body, an end compartment connected to one end part of the cylindrical rod body, and a sealing box which is disposed at the other end of the cylindrical rod body in a sleeving manner. The interior of the end compartment is provided with a soil pressure sensor and a pore water pressure sensor, wherein leading-out wires disposed on the soil pressure sensor and the gap water pressure sensor pass through the cylindrical rod body to be connected with a strain gauge. During soil pressure monitoring, the pressure monitoring rod body sequentially passes through a pipe piece and a grouting layer to reach soil. A joint of the pipe piece with the pressure monitoring rod body is sealed by the sealing box. The soil pressure sensor and the pore water pressure sensor are used for measuring soil pressure and pore water pressure at the same time, and the measurement results are transmitted to the strain gauge through the leading-out wires. Compared with the prior art, the rod is convenient to install and use, is high in reliability, and can measure the soil pressure and the pore water pressure at the same time.

A strain gauge apparatus having a point-distributed sensor for measuring the strain of a mechanical structure. The strain gauge comprises a thin elongated piezoresistive lamina with a shape contour that is symmetric with respect to the longitudinal axis thereof, and the width of the lamina at the center along the longitudinal axis is minimum for the entire lamina length. The point-distributed strain gauge apparatus measures both static and dynamic deformation in the measured structure at a precise location aligned to the targeted center of the sensor lamina.

The invention discloses a wireless hollow inclusion strainmeter and a method for measuring ground stress. The wireless hollow inclusion strainmeter for measuring the ground stress is characterized in that a shell body of the wireless hollow inclusion strainmeter is sealed by epoxy resin, a base material of the shell body is composite ceramic, the wireless hollow inclusion strainmeter for measuring the ground stress comprises a strain measurement portion, an emitting portion and a guiding portion, wherein the strain measurement portion, the emitting portion and the guiding portion are all detachable and recyclable, a directional sensor, a power source and an emitting module are sequentially sealed on the rear portion of the wireless hollow inclusion strainmeter, resistance strain rosettes are inlaid in the middle along the same circumference of the wireless hollow inclusion strainmeter at intervals, and the strain measurement portion, the emitting portion and the directional portion of the wireless hollow inclusion strainmeter can be detached and separated. Three groups of strain rosettes and three groups of direction finders are arranged on the wireless hollow inclusion strainmeter. The strain rosettes and the direction finders are used for respectively transmitting collected signals to an amplifier, and then the signals enter an analog to digital (A/D) converter, analog signals are converted into digital signals, a singlechip is used for sampling, and data are sent out through a wireless module. The wireless hollow inclusion strainmeter for measuring the ground stress has integration and telemetering, and can be recovered and repeatedly used.

The invention has the objective of offering a sensor the allows for measuring the pressure force of the springs on the carbon brushes as well as the actual brush pressure on its contact surface. This is obtained by measuring between the carbon brush, and there is limited space through its holder, and the contact surface and is therefore characterized by the fact that the sensor is thinner than 4 mm, and that it is provided with a target (4) which is suspended in the sensor (1) by means of a mechanically deformable section (3), and where the sensor is fitted with one or more strain gauges (2) that is/are set up as such that it can detect the shearing of the mechanical deformable measuring section under pressure. In contrast to the existing measuring sensors, the measuring strips also connect the suspension points of the mechanically deformable elements with the sensor and/or the suspended target or measuring point through which sensitivity increases and makes the sensor useful for such applications.

The invention provides a load cell which is suitable for being mounted on a connector of an air craft structure. The load cell comprises a cylindrical pin body, a pin seat, a first strainmeter, a second strainmeter, a first strainmeter connecting line and a second strainmeter connecting line, wherein an axial straight groove (a first groove) and an annular groove (a second groove) perpendicular to the straight groove are formed in the body wall of the cylindrical pin body, a line leading hole communicated with the straight groove is formed in the pin seat, the first strainmeter is located at the intersection position of the first groove and the second groove, the second strainmeter is located in the second groove and forms a 90 degree central angle with the first strainmeter, the first strainmeter line and the second strainmeter line are electrically connected with an external sensing signal collecting instrument, and the length direction of the first strainmeter and the length direction of the second strainmeter are identical with the axial direction of the pin body. The invention further provides a large load measuring method capable of carrying out calibration in multiple angles for an air craft. Through the data sensed by the load cell, the size and the direction of the load borne by the air craft structure can be determined, and the load cell can be used for sensing large loads.

An automated coal mining system outfits rotating cutterhead drums with bit blocks and replaceable bit picks according to a lacing pattern. A set of strain gauges are configured to measure the mechanical forces experienced by the bit picks during coal cutting. Measurements are taken that can be processed for indications that the replaceable bit picks have encountered a boundary layer of rock during coal cutting operations, or they are working harder than necessary to cleave coal, or that a better lacing pattern is possible. A resonant microwave patch antenna is mounted on a top surface shoulder of the bit blocks to take impedance measurements of the coal face. The impedance measurements are calibrated according to indications that the replaceable bit picks have encountered a boundary layer of rock. The rotating drum sensor data is wirelessly transmitted back to the machine for analysis and control purposes.

The invention discloses a contact stress sensor. The contact stress sensor comprises a flexible supporting base, a strainmeter, a flexible transmission line and a flexible medium, wherein the flexible supporting base is provided with a plurality of through holes and located at the bottommost position, the strainmeter and the flexible transmission line adhere to the upper surface of the flexible supporting base after being connected into a whole in a lead bonding mode, and the flexible medium covers and adheres to the upper surface of a combination of the strainmeter and the flexible transmission line. Due to the adoption of the flexible supporting base, the flexible transmission line and the flexible medium, the contact stress sensor is capable of bending and deforming along with changes of installation environments, and particularly applicable to measuring contact stress of an upper contact surface and a lower contact surface of an article located in a curved surface structure; due to the fact that the through holes are formed in the supporting base, the contact stress sensor can be used for measuring not only pulling stress but also compressive stress, and measuring accuracy is enhanced.

The invention discloses a seismic test device and test method for an ultrahigh-voltage direct current single-pole composite post insulator. The seismic test device for the ultrahigh-voltage direct current single-pole composite post insulator comprises a vibrating table, a support installed on an installation platform of the vibrating table and a single-pole post insulator with the lower end installed on the installation platform of the support, wherein a counterweight is arranged at the upper end of the single-pole post insulator, a hardware fitting is arranged at the upper end of the counterweight, and at least one accelerometer and at least one strainmeter are arranged on the installation platform of the support; at least one accelerometer, at least one strainmeter and at least one displacement meter are arranged on the single-pole post insulator; at least one accelerometer is arranged on the hardware fitting; and at least one displacement meter is arranged on the installation platform of the vibrating table. The seismic test device and test method for the ultrahigh-voltage direct current single-pole composite post insulator are low in test cost, and can be used for effectively assessing the seismic performance of the single-pole post insulator.

In one embodiment, a surgical instrument includes a housing linkable with a manipulator arm of a robotic surgical system, a shaft operably coupled to the housing, a force transducer on a distal end of the shaft, and a plurality of fiber optic strain gauges on the force transducer. In one example, the plurality of strain gauges are operably coupled to a fiber optic splitter or an arrayed waveguide grating (AWG) multiplexer. A fiber optic connector is operably coupled to the fiber optic splitter or the AWG multiplexer. A wrist joint is operably coupled to a distal end of the force transducer, and an end effector is operably coupled to the wrist joint.; In another embodiment, a robotic surgical manipulator includes a base link operably coupled to a distal end of a manipulator positioning system, and a distal link movably coupled to the base link, wherein the distal link includes an instrument interface and a fiber optic connector optically linkable to a surgical instrument. A method of passing data between an instrument and a manipulator via optical connectors is also provided.

The invention discloses a diagnostic method of an evolution state of a damage field of a concrete dam. The method includes the steps of (1) building a damage field indication variable based on entropy, and defining the entropy of a system as H=F(Q,qi,L,T); (2) calculating the damage field indication variable, and extracting sizes influenced by stress, strain and strainmeter of the damage field from a dam safety monitoring system, wherein the number of strainmeter groups is n, strain energy of a unit of a portion where an ith strainmeter group is located is qi (i=1,2,......,n), total strain energy Q of the area is obtained, and therefore an information entropy function H of a local area is shown in the description, (qi=0, lambada i ln lambada i= 0); and (3) expressing the entropy of the damage field of the concrete dam at a certain moment as F(H)=F(Hh)+F(HT)+F(Htheta) according to a time sequence of the damage field indication variable, and obtaining influence degrees of water pressure, temperature and aging for the damage field and changing trends of the damage field according to an entropy formula to achieve diagnosis and prediction for the damage field. The diagnostic method solves the problems that a traditional method can only diagnose a single measurement point and is lack of relevant diagnosis for changes of measured values of multiple measure points, and comprehensively reflects health states of the dam.

The invention discloses a device and a method for testing lateral impact friction. The device for testing lateral impact friction factors comprises a pneumatic pump, a pneumatic impact device, an arc-shaped rail, an incidence column, a clamp, a support, truckles, an acceleration sensor, a speed sensor, a first strainmeter, a second strainmeter, a first test sample, a second test sample, a transmission column, a belt pulley, a shock absorber, a belt, a variable-frequency motor, a signal acquisition device and a computer. Due to the arrangement of the truckles at the bottoms of the pneumatic impact device and the support, the pneumatic impact device and the support can move on the arc-shaped rail so as to regulate the impact incidence angles of the test samples. Lateral impact friction of materials can be tested by the device. The shapes of the test samples which are used in the invention can be changed, so that the lateral impact friction properties of different types of materials can be tested.

The invention disclose an isolating type triaxial test device, and relates to a device for carrying out mechanical property tests on rock and concrete materials in a pressure state. According to the main structure of the device, the upper portion and the lower portion of a pressure chamber are connected with an upper penetrating cover and a lower penetrating cover respectively to form an overall space, a lower pressing head, a sample and an upper pressing head are sequentially arranged along the center line of the overall space from bottom to top, and the lower pressing head is sleeved with an elastic cushion and isolated from the inner wall of the pressure chamber through an isolating sleeve; hydraulic oil is injected into the space formed by the pressure chamber and the isolating sleeve through the pressurizing device; a strain gage attached to the side face of the sample is connected with a strain gauge to test strain; a press applies test axial pressure to the sample through the upper pressing head. According to the device, pressure oil is located in an airtight space, repeated oil charge or drainage is not needed, and the sample does not need to be wrapped. Due to the fact that the device is simple in structure, small in size and light, operation is easy and convenient, and working efficiency is greatly improved.

The invention discloses an optical fiber drilling strain gauge, which comprises a strain cylinder, liquid, an end cover, a corrugated pipe, a bolt, measurement gratings, a protective cover, an optical cable and ground demodulation equipment, wherein the strain cylinder is used for sensing strain; the liquid is filled in the strain cylinder and used for transferring the strain sensed by the strain cylinder; the end cover is used for sealing; the corrugated pipe is arranged at the bottom of the strain cylinder and used for sensing the change of pressure in the strain cylinder; the bolt is arranged at the bottom of the strain cylinder and used for filling liquid and sealing; the measurement gratings are fixed at the end of the corrugated pipe and the bottom of the strain cylinder and used for measuring the end displacement of the corrugated pipe; the protective cover is arranged at the bottom of the strain cylinder and used for protecting the internal structure of the optical fiber drilling strain gauge; the optical cable is connected with the optical fiber drilling strain gauge arranged at the bottom of a well and the ground demodulation equipment; and the ground demodulation equipment is used for demodulating the wavelength change of the measurement gratings so as to obtain a ground strain value. By using the optical fiber drilling strain gauge, the problems of electromagnetic interference, lightning stroke resistance and null shift of the conventional drilling strain gauge are solved.

The invention relates to a long-term monitoring method based on a beam-type bridge cross section neutral axis safety index. The method comprises the following steps: step S1: designing and installinga dynamic strainmeter assisted by a long scale distance bracket at the top and bottom of a bridge monitoring cross section, receiving and collecting obtained structure strain of the bridge; step S2: searching and preprocessing collected dynamic strain signals once so as to eliminate noise and interference in data; step S3: based on a setting threshold section, extracting an amplitude value causedby same living load and forming a binary array by wave crest values and wave trough values exceeding the threshold section, to obtain a strain response amplitude value; step S4: fitting strain distribution based on plane cross section assumption, and calculating to obtain a neutral axis index; and step S5: performing data integration on the neutral axis indexes within a period of time, analyzing distribution characteristics thereof by using a statistic model, and judging structure safety. Compared with the prior art, the method has the advantages of strong pertinence, stable long-term performance, easy popularization and the like.

The invention provides a semi-implanted hole bottom fiber bragg grating strainmeter geostress measuring device and method. The device includes a fiber bragg grating strainmeter probe, an injection end optical cable, a transmission end optical cable, a fiber bragg grating adjustment analyzer, a signal line, a data acquisition host and an installing rod with an installer. The fiber bragg grating strainmeter probe includes a pedestal and a semi-implantable epoxy resin substrate installed in the pedestal, six fiber bragg grating strainmeters are fixed on the epoxy resin substrate around the circumference at an interval of 60 degrees, after the six fiber bragg grating strainmeters are connected in series, two ends are connected with the injection end optical cable and the transmission end optical cable, the injection end optical cable and the transmission end optical cable are connected with the fiber bragg grating adjustment analyzer, and the fiber bragg grating adjustment analyzer is connected with the data acquisition host through the signal line. The semi-implanted hole bottom fiber bragg grating strainmeter geostress measuring device couples a fiber bragg grating sensor and a hole bottom strain technology, has the advantages of small size, wide measuring range, easy installation, high measuring accuracy, long serving time and the like, and provides a new approach with relatively high precision to complicated rock mass geostress measurement.

The invention discloses a bentonite swelling force experiment device and test method. The device comprises a sealed pressure chamber; a closed sample container is arranged in the middle position in the pressure chamber; the side wall of the sample container is successively provided with a rigid sleeve and a rubber sheath from inside to outside; the sample container is fixed on the pressure chamber through the rubber sheath; a plurality of strain gages are distributed between the rigid sleeve and the rubber sheath; the strain gages are fixed on the outer wall of the rigid sleeve and on the middle height position of the outer wall; the strain gages are connected to a strainmeter; a gas pressure system and a hydraulic pressure system entering into the sample container are arranged on the top of the pressure chamber and below the pressure chamber respectively; an oil hydraulic system communicated to the inner part of the pressure chamber is also provided. The bentonite swelling force experiment device and test method are simple and feasible, accurate measurement for a swelling force in a triaxial pressure experiment process is realized, and meanwhile, the swelling force can be distinguished from other forces.