153 results about "Ambient vibration" patented technology

The invention relates to a physical parameter common-channel phase-shift digital holographic microscopic device based on a diffraction grating, which comprises a lighting unit, a microscopic unit, an interference generating unit and an imaging unit, wherein the lighting unit and the microscopic unit are respectively arranged at two sides of a sample; the lighting unit comprises a laser and a light intensity controller arranged in front of the laser; the microscopic unit comprises a second telescope unit which consists of a microobjective and a third lens; the sample is placed on the front focal plane of the second telescope unit; the interference generating unit comprises a beam splitting unit, a filtering unit, a beam combining unit and a contrast control unit sequentially arranged in the light path direction; and the imaging unit comprises a CCD (charge coupled device) camera which is arranged on the rear focal plane of a seventh lens. The digital holographic microscopic device has the advantages of good stability and no sensitivity to ambient vibration.

A system for reducing the vibration sensitivity of an implantable microphone without an equal or greater reduction in sound sensitivity. The system reduces non-ambient vibrations by placing at least one compliant member into the path of transmission for tissue-borne vibration, but not into the path for ambient sound-induced vibration. More particularly, a compliant member is interposed along the path between a source of non-ambient vibration and an implanted microphone. In one aspect, a compliant base member is disposed between an implanted microphone and an implant wearer's skull. In another aspect, a microphone is compliantly suspended relative to an implant housing using a support membrane. In either aspect, the compliant member (i.e., base member and/or membrane) and the supported member (i.e., housing and/or microphone) define a supported system having a natural or resonant frequency. This natural frequency may be set to a value to advantageously isolate the microphone against transmitted vibration.

An increased frequency power generator that includes a pair of transducers located on opposite sides of a suspended inertial mass. Magnetic attraction is used to couple the mass to each of the two transducers in alternating fashion in response to vibration and other movement externally imparted on the generator. Each transducer includes a suspended magnetic element that couples and decouples to the inertial mass as it reciprocates in the housing due to the applied external moving force. As the inertial mass decouples from one transducer on its way to magnetically connecting to the other transducer, the decoupled suspended magnetic element oscillates at a frequency greater than the imparting force, thereby generating electrical power.

The invention relates to a simultaneous polarization phase-shifting interferometer. The interferometer uses a HeNe laser as a linear polarization coherent light source and comprises reference light and measurement light carrying phase information of a standard lens and a lens to be measured. The reference light and the measurement light are reflected and transmitted by a polarization splitting prism respectively to be combined into one light beam in a same light path respectively, and a 1/4 wave plate and a beam splitter prism are arranged successively on the light path respectively; the light beam can be split into two portions with equal amplitudes by a depolarization splitting prism, and polarization splitting prisms are arranged on two split light paths; and image acquisition devices are arranged on the light paths after the light beams pass through the polarization splitting prisms respectively. According to the simultaneous polarization phase-shifting interferometer, the wave plate and polarization prism structures are used, and polarized light interference is used, so that four interference images with a phase difference of pi/2 successively can be obtained at a same moment, effects of airflows and ambient vibration on measurement can be eliminated, the interferometer can be applied to field inspection of optical systems and optical inspection in complicated and severe environments, and continuous dynamic measurement can be achieved.

The invention provides a piezoelectric giant magnetostrictive combined wideband vibration energy collector, belonging to the technical field of energy. The collector comprises a frame, a bistable beam, a cantilever beam and a permanent magnet, wherein two ends of the bistable beam are fixed on the frame; the permanent magnet is attached on the bistable beam; one end of the cantilever beam is fixed on the frame, and the other end thereof is arranged by means of suspension; and a positive wire magnetostrictive layer, a piezoelectric layer and a negative wire magnetostrictive layer are connected with each other in sequence. The collector adopts a bistable structure, realizes the conversation of magnetism, machine and electricity with the product characteristic of the magnetostrictive effect of a piezomagnetic phase and the piezoelectric effect of a piezoelectric phase in composite material, and leads an MEMS energy conversation component to be capable of obtaining a lager output power under the environment of low-frequency vibration. The collector not only has simple structure, easy manufacture and small volume, but also can run in the low-frequency environment, and can output larger stable power within the range of wider environment vibration frequency.

The invention relates to a piezoelectric generator, and in particular relates to a cantilever-type piezoelectric generator with adjustable base frequency resonant frequency. The cantilever-type piezoelectric generator comprises a clamping device, a piezoelectric layer, a bonding layer, an elastic layer, a U-shaped groove and a mass block, wherein the piezoelectric layer and the elastic layer form a cantilever beam of the cantilever-type piezoelectric generator; the fixed end of the cantilever beam is inserted into the clamping device; the U-shape groove is fixed at the free end of the cantilever beam; and the mass block is fixed in the U-shape groove through a bolt at the center of the U-shaped groove. The effective rigidity of the cantilever beam is changed through the horizontally sliding mass block, so the fundamental resonant frequency of the piezoelectric generator is regulated. By using the cantilever-type piezoelectric generator with adjustable base frequency resonant frequency provided by the invention, energy collection from ambient vibrations with different vibration frequencies is achieved, and the applied range of the piezoelectric vibration generator is broadened.

A piezoelectric transducer for harvesting ambient vibration energy is made up of a curved substructure beam, two half-tube piezoelectric elements and a mass block. One end of the beam is fixed on a vibration base and the other end is attached with the mass block. Two half-tube piezoelectric elements are affixed on the surface of the curved substructure beam. The present invention has a high energy transformation efficiency and a low resonance frequency. It can be applied in implantable devices, wearable electronics and wireless sensor networks.

The invention relates to a dynamic and real-time measuring method in an airspace engine assembling process, and can effectively solve problems in the prior art that the measuring method is long in preheating and standby time, low in measuring speed, affected by surrounding ambient vibration and low in measuring accuracy. The technical scheme for solution comprises the following steps: 1. a central axis of an engine jet pipe is measured; 2. the central position of a bending pipe of the upper part of the engine jet pipe is measured; 3. a reference coordinate system for the engine jet pipe is established; 4. the central axis of a connecting pipe is measured; 5. the central position of the bending pipe of the upper part of the connecting pipe is measured; 6. the reference coordinate system for the connecting pipe is established; 7. the reference coordinate systems of the engine jet pipe and the connecting pipe are converted; 8. assembling is measured; and 9. anti-collision data of the engine jet pipe and the connecting pipe are measured and signals are outputted. The measuring method is short in preheating and standby time, high in measuring speed, not affected by surrounding ambient vibration and high in measuring accuracy so that the measuring method is an innovation on the dynamic and real-time measuring method in the airspace engine assembling process.

The invention discloses a micro-electro-mechanical system (MEMS)-based vibration energy acquisition device. The MEMS-based vibration energy acquisition device comprises an upper pyrolytic graphite thin plate, a suspended permanent magnet, a lower pyrolytic graphite thin plate and a lifting permanent magnet, wherein the upper pyrolytic graphite thin plate, the suspended permanent magnet and the lower pyrolytic graphite thin plate are arranged from top to bottom in sequence; an upper induction coil is arranged on the lower side surface of the upper pyrolytic graphite thin plate; and a lower induction coil is arranged on the upper side surface of the lower pyrolytic graphite thin plate. According to the MEMS-based vibration energy acquisition device provided by the invention, a permanent magnet serves as a suspension body; anti-magnetic material structures are respectively arranged above and below the permanent magnet; an induction coil is arranged on each anti-magnetic material; in order to realize the suspension of the permanent magnet well, the lifting permanent magnet is also arranged on the upper anti-magnetic material structure; in a static state, the permanent magnet is suspended between the two anti-magnetic material structures; and under the action of ambient vibration, the permanent magnet moves up and down without friction, so that induced electromotive force is generated in the upper and lower induction coils and is stored by a power storage loop.

The invention discloses a structural microcrack vibration sound modulation detection system and a structural microcrack vibration sound modulation detection method based on a nonlinear vibrator. The structural microcrack vibration sound modulation detection system comprises a signal generator (1), a low-frequency vibration source (2), a first piezoelectric ceramic wafer (3), a second piezoelectric ceramic wafer (4), a structure (5) with cracks, a permanent magnet (6), a magnet system (7), a signal recording analyzer (8) and a power amplifier (9). The structure with microcracks is used as a cantilever beam to form nonlinear vibrator system, the limitation of a linear vibrator can be overcome by utilizing the nonlinear vibrator, and obvious vibration sound modulation effect in a wide frequency band range can be realized. The system and the method have the technical advantages that the vibration sound modulation detection of the microcrack can be carried out at the non-resonant frequency, so that the high-efficiency detection can be carried out by utilizing the optional ambient vibration. In addition, the system and the method also have the advantages of simple principle, strong interference resistance, high universality and the like.

The present invention discloses a three-dimensional seismic and vibration isolator with adaptive stiffness property in both vertical and horizontal directions. The isolator comprises an upper connection plate, a middle plate, an under connection plate, a disc spring, pre-compressed helical springs, a laminated lead rubber bearing, and viscous dampers. The upper connection plate, middle connection plate and under connection plate are made of high strength low carbon steel with high loading capacity. The upper connection plate and middle plate are tightly contacted by the occlusive design, to guide the vertical motion. The vertical isolation system is made up of the disc spring, pre-compressed helical spring, and viscous damper. The horizontal isolation system comprises the laminated rubber bearing, pre-compressed helical spring and viscous damper. The invention adopts the theory of nonlinear adaptive vibration control technology and can be used to protect building structures or instruments from the seismic strikes or other environmental vibrations.

The invention discloses an input detection method for a touch screen and touch screen equipment. The method comprises: a touch screen identifies a position by press, and confirms the input by disappearance of the press. The touch screen equipment comprises a plurality of pressure sensors and a control unit, wherein the pressure sensors are distributed all around the touch screen and are used to generate and send a signal to a control unit when pressure is sensed and stop sending the signal when the pressure disappears; and the control unit is used to receive the signal sent from the pressure sensors and track the position of the touch screen corresponding to the pressure sensors sending the signal, and when no signal is received from the pressure sensors, the position of the touch screen corresponding to the last sensor sending the signal is taken as the effective input position for inputting. With the adoption of the technical proposal, even in the bumpy environment, a user can make correct and effective input on the touch screen, thereby avoiding the misoperation due to repeated operation and ambient vibration.

A method and system that reduces undesired vibration in a vehicle measures ambient vibration and generates a first command signal based upon the measured vibration. If a first component of the first command signal exceeds a maximum allowable, the first component of the first command signal must be constrained. A residual vibration resulting from the constraint of the first component is then calculated. A second command signal to compensate for the residual vibration is then calculated. Force generators are then activated based upon the constrained first component and the second command signal in order to reduce the vibration.

Disclosed are an embedded rapid quantitative evaluation method for traffic environment vibration and an embedded rapid quantitative evaluation method. A group of intelligent sensor nodes are arranged at test sites to acquire traffic environment vibration data, and each node is used for internally evaluating traffic environment vibration and displaying results in real time. The test sites form a sensor network, each node achieves time synchronization by means of internal clock calibration, and the influence of different distances, different soil layers and different structural factors on vibration propagation is obtained by means of summing up evaluation results of all the test sites. The test sites are positioned at vibration sources and vibration-sensitive places caused by the vibration sources as required or positioned on running public transport vehicles, each node is provided with a vertical analog acceleration sensor and a horizontal analog acceleration sensor, and the data are outputted after passing through a signal conditioner, an analog-to-digital converter and a programmable anti-aliasing filter. The system is convenient in installation and the method is accurate in test.

A piezoelectric transducer for harvesting ambient vibration energy is made up of two elastic beams poled for series operation, a center flextensional component and two proof masses. The center flextensional component serves as the energy harvesting part as well as vibration harvesting inertial mass. The energy harvester is capable of harvesting multi-directional low-frequency vibration energy efficiently. It can be applied in implantable devices, wearable electronics and wireless sensor networks.

A sensor assembly for detecting vibrational energy on a target surface, including at least one target vibration transducer configured to measure vibrational energy associated with at least one target surface; and at least one environmental vibration transducer, each environmental vibration transducer being configured to measure vibrational energy in the immediate vicinity of the environmental vibration transducer wherein the environmental vibration transducer is vibrationally isolated from the target vibration transducer.

The invention discloses a structure dynamic and static parameter uncertainty quantitative analysis system only utilizing output response. The uncertainty of dynamic and static parameters of a structure is quantitatively calculated based on a fast Bayesian method and a quality change method. For a single mode of a certain resonant frequency band, a four-dimensional numerical optimization problem issolved to obtain optimal estimation and a covariance matrix of mode parameters; through first-order perturbation analysis, a vibration mode scaling coefficient, a quality normalization vibration mode, a flexibility matrix and a covariance matrix of prediction displacement can be obtained; and the confidence intervals of the displacement vibration mode, the flexibility matrix and the deflection can be further calculated. Only environmental vibration data is used; expensive manual excitation and load input measurement are not needed, the unique advantage of structural detailed dynamic characteristic recognition the same as that under the input and output thought is achieved, and the method has the advantages of being short in test time, free of traffic closure, high in test precision and high in noise resistance and has good prospects of being widely applied to actual bridge performance evaluation.

The invention discloses a radial shear interference wavefront detection device based on a micro-optical device, comprising a polarization direction modulator (1), a polarization ring path direction shear system CRSS, a micro phase modulation array MPA and a photodetector (9 ), the micro-phase modulation array MPA is composed of a microwave chip array (7) and a polarizer (8). Using the birefringence effect of a birefringent crystal, the micro-phase modulation array is fabricated by a micro-optical processing method to realize the space phase of the radially sheared beam. The wavefront phase distribution of the beam to be measured is inverted by a random phase shift algorithm. The invention adopts an all-common optical path structure, which can be immune to environmental vibration and has a stable interferogram; the structure is compact and easy to transplant; the micro-optical device has a large scale, low precision requirements, low cost, and is convenient for mass production; it has a wide spectral range and is insensitive to chromatic aberration. The invention can be applied to the fields of adaptive optics, optical detection, thermal imaging and the like.

A system for reducing the vibration sensitivity of an implantable microphone without an equal or greater reduction in sound sensitivity. The system reduces non-ambient vibrations by placing at least one compliant member into the path of transmission for tissue-borne vibration, but not into the path for ambient sound-induced vibration. More particularly, a fluid filled compliant member is disposed between an implanted microphone and an implant wearer's skull. The compliant member and the implanted microphone define a supported system having a natural or resonant frequency. This natural frequency may be set to a value to advantageously isolate the microphone against transmitted vibration.

The invention discloses a method and a system for predicting environmental vibration caused by urban rail transit. The method comprises the steps: obtaining the vibration speeds of simply supported concrete box girders of an urban rail transit elevated train at different speeds; performing spectral analysis on the vibration speed to obtain an analysis result; calculating according to the train track bridge coupling analysis model to obtain a frequency spectrum result; comparing the analysis result with the frequency spectrum result, and discovering that a first peak frequency related to a structure predicted according to a theoretical formula corresponds to a second frequency related to a periodic excitation frequency; and predicting environmental vibration caused by urban rail transit. According to the method, the physical significance of the peak frequency of the test beam within the 100 Hz range is explained, and environmental vibration caused by urban rail transit is predicted.

Disclosed herein are a method and program for calculating the stiffness coefficient of a bridge by using a finite element model. The method of calculating the stiffness coefficient of a bridge by using a finite element model includes: step (a) of receiving the information of a bridge in an ambient vibration test via a simulator for a finite element model; step (b) of calculating relative girder displacements (RGDs) by converting the deflection displacements of the bridge into proportions; and step (c) of calculating the stiffness coefficient k of the bridge from the error function of the bridge using the relative girder displacements (RGDs) as a variable by taking into account the deflection shape of the bridge in the relative girder displacements (RGDs) calculated at step (b). In this case, the stiffness coefficient k of the bridge is calculated using ambient vibration test data.

The invention discloses a system and a method for testing influence of a plume field of a high-thrust rocket engine to laser transmission under atmospheric conditions. The system carries out data acquisition and comparison by adopting two analysis light paths to eliminate the influence of ambient vibration to a test result, carries out remote control by adopting a wireless local network, and then analyzes laser energy attenuation, directing deflection and light beam quality deterioration conditions caused by the plume field by adopting an off-line image processing method so as to completely estimate the influence of the plume field of the high-thrust rocket engine to laser transmission characteristics under atmospheric conditions.

The invention relates to a linear guide rail-bearing type motion decoupling three-dimensional vibration isolation support which is characterized by comprising a vertical vibration isolation system anda horizontal vibration isolation system. The vertical vibration isolation system comprises a vertical vibration isolation mechanism, a connecting and fixing mechanism, an instability preventing mechanism, a positioning mechanism and a motion decoupling mechanism. The vertical vibration isolation mechanism is responsible for providing a vertical self-adaptive rigid characteristic needed by vibration isolation. The whole device plays connecting and bearing roles through the connecting and fixing mechanism; the instability preventing mechanism and the positioning mechanism are arranged around anelastic element in the vertical vibration isolation mechanism and are matched to guarantee the stability of the vertical vibration isolation mechanism. The linear guide rail-bearing type motion decoupling three-dimensional vibration isolation support can be used for structures and precision equipment affected by environmental vibration, and can have an effect of isolating seismic oscillation andimpact while isolating the environmental vibration.

Provided is a miniature piezoelectric type energy collector based on low-frequency ambient vibration driving. The miniature piezoelectric type energy collector based on low-frequency ambient vibration driving comprises a base, a cantilever beam, a mass block and an energy storage circuit, wherein the cantilever beam comprises a plurality of straight arm beams which are parallel to one another, every two adjacent straight arm beams are connected through a connecting piece so that the whole cantilever beam with a head end and a tail end can be formed, the head end is fixed to the base, the mass block is installed at the tail end, only one connecting piece is arranged between every two connected straight arm beams, and all the straight arm beams and the connecting pieces are arranged on the same plane; the energy storage circuit comprises a first bridge rectifier diode D1, a second bridge rectifier diode D2, a third bridge rectifier diode D3, a fourth bridge rectifier diode D4, a storage electrolytic capacitor C with the filtering function, and a load resistor RL. The miniature piezoelectric type energy collector based on low-frequency ambient vibration driving has the advantages that the length of the cantilever beam is increased in an equivalent mode, miniaturization of a device is achieved, the natural vibration frequency of the device is reduced, and output power is improved.