6854results about "Vibration testing" patented technology

The method comprises: using a sensor to collect the characteristic signals; the collected signals about each kind of running state are sent to the data processing module; after processed, the signals are sent to the computer system; said computer system comprises a device database, a symptom event database, a diagnosis knowledge database; a device database and signal analysis module, a symptom acquiring module, a diagnostic reasoning module, and a diagnosis explaining module; the software of the data processing module makes data exchange; the symptom event database exchanges data with the diagnostic module, data processing module; the diagnostic knowledge exchanges the data with the failure processing module, knowledge acquiring module and data processing module.

The invention relates bridge structure safety evaluation technology by means of combining vibration measuring and structural model analysis techniques for bridge erosion evaluation and pre-warning monitoring applications. This technology can also be applied for long-term bridge structure monitoring and safety evaluation as well as judgment and evaluation of rail structure abnormality.

The invention discloses a method for testing the assembly performance of a rotor of an aircraft engine, which comprises the following steps of: firstly exciting and vibrating a rotor of an aircraft engine with a vibration exciter; obtaining a multiple carrier-coupled impulse response signal of the rotor of the aircraft engine with a vibrating sensor and signal-acquiring system software; analyzing the obtained multiple carrier-coupled impulse response signal of the rotor of the aircraft engine by means of dual-tree complex wavelet transform to obtain eight signal carrier-coupled impulse response signals of the rotor of the aircraft engine; and distilling the average assembly performance index of the obtained eight signal carrier-coupled impulse response signals of the rotor of the aircraft engine, wherein the assembly performance of the rotor of the aircraft engine is judged to be qualified if the obtained average assembly performance index is larger than or equal to 10, and the assembly performance of the rotor of the aircraft engine is judged not to be qualified if the obtained average assembly performance index is less than 10, so that the rotor needs to be repaired.

An acoustic monitoring device has at least two acoustic sensors with a triggering mechanism and a multiplexing circuit. After the occurrence of a triggering event at a sensor, the multiplexing circuit allows a recording component to record acoustic emissions at adjacent sensors. The acoustic monitoring device is attached to a solid medium to detect the occurrence of damage.

The invention discloses an exciting device for testing dynamic property of an MEMS microstructure or micro-device and belongs to a minitype mechanical electronic system. A structure of the device comprises that: a microstructure to be tested is arranged on a crossed spring strip of the top part; the crossed spring strip is arranged on the top part of a sleeve by a bolt; piezoelectric ceramics, an upper connecting block, a steel ball, a lower connecting block and a pressure sensor are arranged inside the sleeve; the bottom of the piezoelectric ceramics is fixed on the upper connecting block; the top part is contacted with the crossed spring strip to change the thickness of an adjustable washer; the piezoelectric ceramics is pressed by the crossed spring strip; the pressure sensor is arranged on a base plate; and the base plate and the sleeve are connected by a bolt. The exciting device has the advantages that in normal environment the device can carry out excitation on the MEMS microstructure, can remove shearing force produced in the using process of the piezoelectric ceramics and effectively prolong the service life of the piezoelectric ceramics through exertion of certain pretightening force on the piezoelectric ceramics at the same time; and the device can measure the output force of the piezoelectric ceramics by the pressure sensor, thereby conveniently seeking a frequency response function of the microstructure and obtaining dynamic property parameters of the microstructure.

An apparatus (10) for applying at least one load to a specimen (12) according to one embodiment of the invention may comprise a mass (18). An actuator (20) mounted to the specimen (12) and operatively associated with the mass (18) moves the mass (18) along a linear displacement path (22) that is perpendicular to a longitudinal axis of the specimen (12). A control system (26) operatively associated with the actuator (20) operates the actuator (20) to reciprocate the mass (18) along the linear displacement path (22) at a reciprocating frequency, the reciprocating frequency being about equal to a resonance frequency of the specimen (12) in a test configuration.

The invention relates to an eccentric pump vibration accidence fusion diagnose method and relative vibration signal collector, wherein said invention is characterized in that: it uses the eccentric pump vibration signal collector to collect the normal state, the quantity imbalance, asymmetry rotate and loose base of eccentric pump; uses wavelet decomposition and reconstruction to extract the character of vibration signal; and inputs the character vectors into sub fuzzy neural networks I and II; to be treated and replace the relation factor matched with sensor signal function; the whole fuzzy neural network comprises data fuzzy layer, input layer, hidden layer and output layer; uses D-S theory to obtain the fused signal function distribution, realize the fusion diagnose on normal state, quantity imbalance, asymmetry rotate and loose base. The invention has simple structure and high effect.

The invention discloses a steam turbine blade vibration test method and device. The method steps are that firstly, a blade force vibration status is analyzed and a blade excitation force mathematical model is built. Secondly, an excitation force is imposed on the blade by a vibration source. The frequency of the excitation force is regulated until resonance is generated between the blade and the vibration source. Vibration characteristics parameters values of the blade under the excitation force are measured. Thirdly, blade damping characteristics parameters, including modal damping ratio, damper contact stiffness and blade dynamic stress, are worked out according to the vibration characteristics parameters values. The device includes a test bed, a blade clamping mechanism arranged on the test bed, an excitation generator, a vibration parameter detector and a data processing system. The excitation vibration generator is fixed on the test bed. The excitation vibration head of the excitation vibration generator is fixed with the blade. Corresponding to the blade, the vibration parameter detector transforms the vibration signals of the blade into electric signals, which are input into the data processing system. The invention proves the vibration mechanism of the damping blade. A calculation model of the damping blade is constructed through the test parameters. Experience design is terminated. The blade design is standardized to step into a scientific design orbit.

The invention relates to a dynamic characteristic parameter test device of a sliding guide rail junction surface, which can be simplified into a single degree of freedom system. The device comprises a base, an installation platform, a fixed guide rail, a wedge-shaped block, an inlaid strip, a sliding block, a plurality of piezoelectric type acceleration sensors, a vibration exciter, an elastic rope, an impedance head, a stand, a normal force applying bolt, a rubber ring, a charge amplifier, a data acquisition unit, a power amplifier and an electronic computer. Compared with the prior art, thedynamic characteristic parameter test device has the advantages that: the structure is compact, the test principle is distinct, dynamic characteristic parameters of the junction surface under different load states can be measured by adjusting the pretightening force of a normal force applying bolt, the vibration exciting force direction passes through the gravity of the sliding block during measurement so that vibration signals of the sliding block and the base can be measured simultaneously, the influence of the vibration signals of the base is eliminated when a frequency response function of a system is calculated, and the characteristics of high efficiency, high stability and high precision are achieved.

Disclosed herein is an apparatus for evaluating the safety of a building. The apparatus includes first and second measurement instruments which measure earthquake accelerations of the top and bottom stories, a fast Fourier transform unit which performs fast Fourier transform on the earthquake accelerations, an integration unit which double-integrates the measured earthquake accelerations and creates drift data of the top story and the bottom story, a maximum inter-story drift ratio calculation unit which calculates a maximum inter-story drift ratio, a natural frequency change rate calculation unit which determines a natural frequency of the building, and compares the natural frequency with an ambient natural frequency of the building so as to calculate a natural frequency change rate, and a building safety evaluation unit which compares the maximum inter-story drift ratio and the frequency change rate with preset evaluation criteria and outputs a result of evaluation in the safety of the building.

The invention discloses a ground testing system for on-track micro vibration of a spacecraft, which comprises a vibration isolating foundation, a supporting truss with a framework structure, a suspended positioning platform, a gravity suspended compensation unit, an integrated control subsystem, a micro vibration measurement subsystem and a test data processing and analyzing subsystem, wherein the vibration isolating foundation is connected with the ground, the supporting truss with the framework structure is fixedly supported on the vibration isolating foundation, the suspended positioning platform is supported on the supporting truss, the gravity suspended compensation unit is hung on the suspended positioning platform, and the integrated control subsystem is used for controlling the positioning and the fixation of the suspended positioning platform via coordination of sensors in various positions and performing the overall integrated control on the state of the system. By adopting the system, the ground simulation of the on-track micro vibration environment, the measurement of micro vibration and the data processing can be realized for the spacecraft at the system level and the component level, the technical level of testing the micro vibration of the spacecraft can be improved, and the demands for testing and verification of the on-track micro vibration environment in research on the spacecraft, particularly the high-precision satellite, can be satisfied.

The invention relates to a vibration table detection instrument field. In order to overcome the defects of the prior art, a signal processing approach is designed to allow a virtue instrument to be applied to the measurement field and an instrument suitable for measurement is designed accordingly on the basis of the signal processing approach. More particularly, the invention relates to a virtual vibration table detecting signal processing method and the instrument. The method comprises the processes: (1) the acceleration value of the vibration table is collected and converted into electric signals; (2) the signal is conditioned by a signal conditioning instrument; (3) the conditioned signal is collected by a data collecting card and transmitted to a computer; (4) the signal is preprocessed by the computer; (5) the preprocessed signal is discrete Fourier transformed and digital signal frequency domain filtered; (6) in the end, a speed component is output after the signal is integrated for one time; a displacement component is output after the signal is integrated for two times. The detection instrument comprises an acceleration sensor, a signal conditioning instrument, a data collecting card and a computer.

A system and method for producing and controlling a random signal with simultaneous control of both the power spectral density (PSD) and kurtosis (100) where a controlled signal is measured from a transducer, and converted to a PSD (111) using a Fast Fourier Transform (FFT). The measured PSD is compared (117) with a reference PSD (121) where an adaptive filter (119) is updated to compensate for the error. Simultaneously the kurtosis of the measured data is computed (125) and compared to a reference kurtosis (123). A feedback control loop (127) is employed to adjust the kurtosis of a white noise random generator with variable kurtosis (101). This white noise is then filtered by the adaptive filter (119) to provide the output signal used to drive the control process.

The invention provides a method and system used for monitoring the vibration states of impellers of wind generating sets. The method includes the steps that the vibration acceleration of a predetermined measuring point on a vane of each wind generating set in at least one direction is detected according to a preset detection period, data of operating parameters of at least one of the wind generating sets are synchronously acquired, and the acquired data of the operating parameters of the set and the detected vibration acceleration data are recorded; data sets of recorded operating parameter data and recorded vibration acceleration data exceeding the preset amount are selected; according to the operating parameters of the wind generating sets, vibration acceleration data detected when the wind generating sets are in abnormal working conditions are removed from the data sets; operating mode analysis is carried out on the vibration acceleration data detected at the measuring points of the vanes, at least one of the inherent frequency, the damping ratio and the vibration mode of each vane in the operating state is extracted, and whether the impellers of the wind generating sets break down or not are determined according to the extracted inherent frequency, damping ratio and vibration mode.

In the invention, a high g value impact acceleration simulation test system, a method thereof and the application of the test method, belonging to the technical fields of impact testing and tests. The test system comprises three parts: the high g value impact acceleration simulation test system, the test method and the application of the test method. In the high g value impact acceleration simulation test system and the test method, an impact acceleration signal with the amplitude of (0.1-1.5)*10<5>g and impulse width of 150-600mus is generated by the collision of a projectile shot by a gas cannon and a collided object, thus providing the test system and the test method for various performance researches on a projectile-borne electronic instrument under high impact environment. The test system and the test method have advanced designs and leading technical performances, can be applied to the aspects of projectile-borne testing instrument, inertial measurement unit, black box, intelligent fuze, gyro, MEMS device and the like for the calibration of an acceleration storage testing device under application environment, high impact resisting performance research of the projectile-borne electronic instrument, cushion performance research of a cushion part of a projectile-borne testing device and return-to-zero characteristic research of a high impact accelerometer.

Output-only modal testing of an object. Vibrations are excited in said object and measured by a number of vibration sensitive detectors. From the data of the measurements, a spectral density matrix function is determined. From this density matrix, auto spectral densities for the individual modes are identified performing a decomposition based on the Singular Value Decomposition technique. From the auto spectral densities of the individual modes, natural frequencies and damping ratios for the modes can be estimated, and from the singular vectors of the Singular Value Decomposition, the modes shapes can be estimated.

The invention belongs to the technical field of vibration test, in particular to a thin-walled structure part vibration test device and a method based on a piezoelectric ceramic vibration exciter. The device comprises a signal generator, a piezoelectric ceramic drive power supply, a piezoelectric ceramic vibration exciter, a feedback attenuator, a laser vibration meter, a data acquisition analyzer and an upper computer. The method comprises the steps of performing modality test on a thin-walled structure part, determining a linear relationship between excitation voltage and critical excitation frequency of the signal generator and calibrating an excitation force of the piezoelectric ceramic vibration exciter based on a cantilever theory. According to the device and the method, an excitation signal can be effectively acquired; the magnitude of the excitation force when the piezoelectric ceramic vibration exciter excites the structure part is defined; the stable designated excitation force and the linear excitation signal of the excitation frequency can be generated; influencing factors of non-linear piezoelectric ceramic excitation are effectively eliminated; the piezoelectric ceramic vibration exciter is adopted to realize high-frequency vibration excitation; additional mass is low; and the device is convenient to use.

A method for bridge vibration testing and dynamic property recognition based on video monitoring comprises a step A of performing system construction, initial configuration and displacement obtaining; a step B of performing multipoint structure dynamic displacement obtaining, continuous collection and storage; a step C of preprocessing displacement time-history data; and a step D of processing free vibration response signals to obtain a modal parameter.

A testing apparatus for use with a data storage component that includes a base platform and a retaining element coupled to the base platform. The retaining element is sized and configured to retain the data storage component. The retaining element is linearly movable relative to the base platform during a linear acceleration mode without substantial rotational movement. The retaining element is rotationally movable relative to the base platform without substantial linear movement during a rotational acceleration mode. The testing apparatus further includes an actuator disposable in mechanical communication with the retaining element for moving the retaining element relative to the base platform.

The invention relates to a torsional vibration excitation device and a test bed of a vehicle drive system, comprising a torsional vibration excitation device, a wheel loading device, an inertia flywheel and a testing system. The torsional vibration excitation device is used for providing a torsional vibration excitation torque for the torsional vibration research of the drive system and providing power for the drive system. The wheel loading device is used for supporting wheels and simulating a carload acting on the wheels, pressing the wheels towards the inertia flywheel through a mechanical loading mode and locking the positions of the wheels. The testing system is used for collecting pull and pressure signals as well as rotate speed signals output by a sensor and analyzing the pull and pressure signals as well as the rotate speed signals. The torsional vibration excitation device comprises a driving motor, a driving gear shaft, an excitation gear shaft and an excitation motor, wherein the driving motor drives the driving gear shaft to rotate through the belt of the driving motor, the excitation motor drives the excitation gear shaft to rotate through the belt of the excitation motor, and the excitation gear shaft is coaxial with the driving gear shaft.

The invention discloses a transmission line oscillation positioning system based on micro inertial measurement combination. The transmission line oscillation positioning system comprises a monitoring center and a pole and tower monitoring host machine which are connected with each other, wherein the pole and tower monitoring host machine is wirelessly connected with at least two wireless inertialsensor nodes; and each wireless inertial sensor node comprises a triaxial acceleration sensor and a triaxial gyroscope. By the method for positioning by adopting the system, the wireless inertial sensor nodes acquire acceleration values and state space angles of a lead wire monitoring point in three directions; the monitoring center processes and analyzes the data of each monitoring point by adopting algorithms, such as Fourier transformation, a least square method, digital filtering, Kalman filtering, matrix coordinate transformation, frequency domain integral operation so as to fit to acquire an oscillation trace of a whole line, and corrects the oscillation line according to a digital model of a relation between an oscillation characteristic value and a micro meteorological condition; therefore, the precision of oscillation monitoring is improved and the most direct and intuitive monitoring of transmission line oscillation can be realized.

A nondestructive method of and apparatus for detecting degradation of reinforcing members embedded within a structure is disclosed. Degradation can arise from many sources, such as corrosion, fracture, cracking, fatigue, chemical reaction, etc. The device includes an inducing instrument(210) to induce a vibration of the reinforcing members (110)and a measuring device (220) to detect the vibration of the reinforcing members. The measurement is analyzed to detect the presence of reinforcing member degradation or reinforcing member-to-concrete bonding. The device may include a controller (230) to enhance the detection. The device may also include an amplifier (240) to further increase the energy in the waves imparted to the structure and the acoustic waves detected by the measuring instrument.(220)

A vortex-exciting vibration test device of flexible pipe fittings mode set horizontally in pull water pool is prepared as passing pipe fittings model through flow-speed increasing unit; setting said model and said unit vertically in pull water pool; supporting two ends of said model by support mechanism; using horizontal test support to connect said unit and support mechanism with trailer and distributing various instruments of measurement-analysis system in said model, said units, said mechanism, said support and said trailer.

A health and usage monitoring system (HUMS) and method for monitoring the health and / or usage of one or more components of a vehicle. In various embodiments, the present invention uses a plurality of wireless sensors configured, when activated by a vibration of the vehicle, to monitor one or more components of the vehicle and to communicate health and / or usage data of the one or more components of the vehicle to a data access point. The data access point may relay real-time health and / or usage data to an operator of the vehicle, or the health and / or usage data may accessed later. Such a system allows critical components of the vehicle to be monitored so as to reduce failures, and so that repairs to, or replacements of, the critical components of the vehicle may be planned, thus reducing unscheduled downtime.

The invention discloses a spatial six-degree-of-freedom vibration measuring and damping vibration attenuating method. The method comprises the following steps of: 1) erecting six-displacement-sensor parallel measuring and damping vibration attenuating mechanism; 2) fixing a detected motion object and a fixed platform; 3) obtaining a motion variation rule by using an expansion variation displacement time of an expansion pull rod, and obtaining a vibration rule of the detected motion object by using a measurement algorithm with a positive solution; 4) obtaining a damping value of a six-degree-of-freedom controllable damper required by the vibration by using a damping vibration attenuating algorithm; and 5) adjusting the damping value of the six-degree-of-freedom controllable damper to a value obtained by the damping vibration attenuating algorithm. According to the invention, six-degree-of-freedom measurements of three vibration displacements and three vibration angles of the motion object at the same measurement point are achieved by using one set of mechanism; meanwhile, the vibration control of the motion object can be achieved; and the spatial six-degree-of-freedom vibration measuring and damping vibration attenuating method disclosed by the invention has the advantages of high accuracy, simple structure, good flexibility, strong adaptability, wide application range and the like.

The invention relates to a system and a method for measuring time-sharing quick steady-state sine sweep excitation frequency response function, which belong to the technical field of vibration tests. An excitation system adopts a vibration exciter and a power amplifier. A force sensor and a vibration sensor are adopted to measure an exciting force signal and a vibratory response signal of the system at the same time. A charge amplifier is adopted to condition and filter the signals. A data acquisition system connects a data acquisition card with a connecting terminal through a high-performance shielded cable and is connected with a general computer to acquire and send data. The generation of a sweep signal and the data processing, analysis, storage and display of an exciter response signal are achieved by adopting software based on the general computer. The system and the method achieve quick steady-state sine sweep excitation, the complete cycle sampling of the exciter response signal, and precise and reliable frequency response function curve. The test system is guided by computer programs and is finished automatically, the test method is precise and reliable, and the system and the method have important meaning on testing the dynamic properties of structural elements.

The invention discloses a method and a system for analyzing vibration and diagnosing failure for a wind generating set. The method comprises the following steps: firstly, acquiring vibration data of the wind generating set; finishing the analysis of the vibration data of the wind generating set according to structure parameters, history records and knowledge base of the wind generating set to generate a human-editable analysis report; diagnosing according to a vibration monitoring analytical standard and the operating state of the wind generating set; leading the diagnosis result to form a vibration monitoring report, and submitting the vibration monitoring report to a user; and finishing maintenance to the wind generating set according to the vibration monitoring report by the user. The technical scheme of the invention can greatly reduce workload of the vibration analysis of the wind generating set, and improve efficiency and accuracy of vibration analysis and failure diagnosis of the wind generating set.

A vortex-exciting vibration test device of flexible pipe fittings model set vertically in pull water pool is prepared as passing pipe fittings model through flow-speed increasing unit; setting said model and said unit vertically in pull water pool; supporting two ends of said model by support mechanism; using vertical test support to connect said unit and support mechanism with trailer and distributing various instruments of measurement-analysis system in said model, said units, said mechanism, said support and said trailer.

The invention relates to a complete set of test method of a soft soil iron structure vibration table. The method comprises the following steps of: preparation of soft soil in a model box in a vibration table model test, design of a model box, and typical subway station structure and joint structure test simulation and measurement system. The station structure and joint structure model can be manufactured from a particle reinforced concrete structure; and the inner side of the rigid boundary in the excitation direction of the model box is lined with a flexible material. The rigid fixing boundary is made into a support frame by angle steel, a wood plate is used as the side wall of the box body inside, and the bottom material is steel plate. In a direction vertical to the horizontal vibration direction, each inner wall of the box body is lined with a polystyrene foam plastic plate; and in the direction of the horizontal vibration, a polystyrene film is stuck on each inner wall of the box body, and broken stone is stuck on the bottom of the model box. A resistance strain gauge type pressure box of the measurement system measures the ground-breaking pressure time interval of the soil body in the model box, a resistance strain sensor measures the strain time interval of the station structure, and a piezoelectric type acceleration sensor measures the acceleration time interval of the soil body and the station structure. The method provided by the invention realizes vibration table test for the station structure and running tunnel structure community in the underground railway building structure of a soft soil region.

The invention discloses a threaded fastener transverse vibration test device and method. The device comprises a transverse vibration platform, a transmission system, a clamp system, an installation base and a measuring device; one end of the transmission system is fixed to the vibration platform through a bolt, and the other end of the transmission system is fixed to a movable plate in the clamp system; a fixed base of the clamp system is fastened to the installation base through a T-shaped groove; the transmission system is provided with a pull pressure sensor, and the clamp system is provided with a gasket type force sensor. The device and method can simulate high-frequency vibration, achieve electrodeless amplitude modulation, monitor changes of transverse shear force and axial pre-tightening force of a threaded fastener in a vibration process in real time, and test the anti-loose characteristic of single bolts and bolt sets (distributed in a linear, rectangular and circular mode) with different specifications. The device and method provide a basis platform and data support for engineering technicians to analyze anti-loose performance of various threaded fasteners and assess effectiveness of various anti-loose methods.