9 results about "Internal resonance" patented technology

This invention relates to the field of wave energy generation, and more particularly to a dual-frequency high-efficiency energy harvesting method for a spring pendulum wave energy generator. The energy harvesting method includes the following steps: the spring pendulum wave energy generator enters the working state and directly contacts seawater, moving in undulating motion with the waves; the two directional degrees of freedom of the spring pendulum wave energy generator are adjusted; the spring pendulum wave energy generator uses a swing arm to adjust the resonant frequency of the oscillation degree of freedom of the float; the spring pendulum wave energy generator uses the resonant frequency of the hemispherical float and the spring-adjusted float along the radial degree of freedom of the long swing arm; a spring is added to the swing arm to make it a nonlinear spring pendulum structure, and its internal resonance characteristics are used to realize the mutual switching of the float's kinetic energy between the oscillation and radial degrees of freedom.

The application discloses a kind of based on independent parametric internal resonance principle's shock absorber and shock absorbing method, the shock absorber includes: power transmission wire;Several cantilever shock absorbers are fixed on the power transmission wire by fastening screw and nut;The spatial position of the power transmission wire and cantilever shock absorber is orthogonal, and the ratio of natural frequency is preset value;The cantilever shock absorber and power transmission wire constitute independent parametric internal resonance system, and the modal damping of cantilever shock absorber is obtained by simulating the independent parametric internal resonance system under the condition that the ratio of natural frequency is preset value and the shock absorbing effect of cantilever shock absorber is best, so as to adjust the modal frequency of cantilever shock absorber.The application utilizes independent parametric internal resonance principle, realizes the substantial absorption of power transmission line vibration energy to achieve the purpose of passive shock absorbing.

The application discloses a flexible mechanical arm main resonance control method based on nonlinear feedback and time delay feedback, and mainly comprises the following steps: discretizing the transverse deformation of the flexible mechanical arm by using the assumed mode method to obtain the vibration equation of the flexible mechanical arm; introducing a linear feedback control term, a nonlinear feedback control term and a time delay feedback control term to constitute a control signal model of a vibration absorber; constructing the control signal model of the vibration absorber; establishing a flexible mechanical arm system vibration control model of the vibration absorber by using Kane equation; applying a multi-scale method to solve the approximate analytical solution of the system vibration equation to obtain a single mode solution and a double mode solution of the system steady-state response; and finally, under the condition that the flexible mechanical arm system vibration control model of the vibration absorber coexists with the internal resonance condition and the main resonance condition, the main resonance of the flexible mechanical arm is controlled, and the mode amplitude of the first order mode of the flexible mechanical arm in the main resonance is well inhibited.

The invention relates to an MEMS (micro-electromechanical system) gyroscope array error suppression device and method based on active piezoelectric excitation, and the MEMS gyroscope array error suppression device and method based on active piezoelectric excitation are characterized in that controlled low-frequency micro-amplitude mechanical vibration is applied to an MEMS gyroscope array through a piezoelectric exciter; the internal resonant state of the gyroscope is physically modulated to reduce the temporal correlation of scale factor errors, converting systematic deviations into random noise. In combination with a base matched with a thermal expansion coefficient and bimodal signal processing, the device separates effective signals while suppressing thermal stress interference, so that an array fusion algorithm can eliminate common-mode errors, and the measurement precision is improved to be within 0.5 degree on the premise of not changing the sensor process.

The application relates to a MEMS gyro array error suppression device and method based on active piezoelectric excitation. The MEMS gyro array error suppression device and method based on active piezoelectric excitation designed by the application applies controlled low-frequency micro-amplitude mechanical vibration to the MEMS gyro array through a piezoelectric exciter, physically modulates the internal resonance state of the gyroscope to reduce the time correlation of the scale factor error, and converts systematic deviation into random noise. In combination with a base matched in terms of thermal expansion coefficient and double-mode signal processing, the device can separate effective signals while suppressing thermal stress interference, so that the array fusion algorithm can eliminate common-mode errors, and the measurement precision is improved to within 0.5 degrees without changing the sensor process.

The invention relates to the technical field of energy collection, and discloses a multi-directional vibration energy collection type intelligent spacer for a power transmission line, which can automatically collect vibration energy of the power transmission line from multiple directions and improve the energy conversion rate. The power transmission line multidirectional vibration energy collection type intelligent spacer comprises a response module and a power generation module, and the power generation module is installed on the response module. The power generation module comprises a first power generation assembly and a second power generation assembly. The response module comprises a rotating shaft, an internal resonance response assembly and a rotating assembly, the rotating assembly and the internal resonance response assembly are both connected with the rotating shaft, the first power generation assembly is installed on the internal resonance response assembly, and the second power generation assembly is installed on the rotating assembly; the rotating assembly comprises a stator and a rotor; the rotor is fixedly mounted on the rotating shaft; under the action of external force, the internal resonance response assembly swings around the rotating shaft to vibrate the spring mass system, so that the first power generation assembly generates a first electric signal; and the internal resonance response assembly drives the rotor to rotate so as to enable the second power generation assembly to generate a second electric signal.

This invention relates to the field of vibration control technology and discloses a structural coupling vibration isolation system and method for cleanrooms. The system is installed on the floor slab of a building structure and includes an isolation support frame system, a quasi-zero stiffness main support unit, a segmented viscous damper, and a nonlinear tuned mass damping module. The isolation support frame is lowered in the middle to form a suspended foundation pit. The quasi-zero stiffness unit effectively isolates external low-frequency vibrations. The segmented damper achieves low-resistance, high-energy-dissipation limiting for micro-vibrations and large displacements. The equipment base acts as a tuned mass block to adaptively absorb internal resonant energy. This invention, by constructing a coordinated structural coupling vibration control system, can simultaneously achieve ultra-low frequency vibration isolation, wideband adaptive vibration absorption, and seismic safety protection, making it suitable for micro-vibration control scenarios of precision equipment in semiconductor cleanrooms.

This invention discloses a method for identifying internal resonance in flexible structures based on acoustic measurements, comprising: 1. Calculating the natural frequencies and mode shapes of the flexible structure through dynamic modeling and eigenvalue solving to determine that the structure has approximately reducible mode frequencies, satisfying the preconditions for internal resonance; 2. Arranging several sound pressure sensors near the flexible structure to collect the time-domain signal of the dynamic radiated sound pressure of the structure; 3. Using fast Fourier transform to extract the sound pressure amplitude of each sound pressure sensor near a certain low-order natural frequency, and plotting the directivity curve of the sound pressure amplitude with respect to the spatial position of the sensor. By comparing the directivity curve with the geometric characteristics of the mode shapes of the flexible structure, it is determined whether the structure is in an internal resonance state. This invention can identify whether the low-order coupling modes of the flexible structure are excited by monitoring the spatial directivity curve of the radiated sound pressure of the flexible structure, thereby achieving accurate and intuitive identification of internal resonance phenomena in flexible structures through non-contact, simple, and convenient acoustic measurements.

The invention discloses a road vibration broadband low-frequency energy collection device and system based on a nonlinear superstructure, and relates to the technical field of road engineering. The device comprises a bearing packaging shell, a nonlinear superstructure unit array, an energy gathering and frequency up-conversion mechanism, an energy converter, an electric energy management module, a modular interface and a state monitoring unit, through magnetic tuning, pre-tightening tuning or negative stiffness tuning of the nonlinear tuning assembly, the nonlinear superstructure unit forms a bistable situation trap, a multi-stable situation trap or quasi-zero stiffness characteristic, energy is gathered and dispersed in combination with internal resonance coupling, low-frequency wide-spectrum vibration is adapted, and parameter drift can be dealt with; the low-frequency-to-high-frequency conversion is realized by means of an energy gathering and frequency up-conversion mechanism, the electric energy conversion efficiency is improved, a distributed energy supply network is formed in a multi-device array manner by matching with a protective shell and a modular interface, and the power supply requirements of various roadside devices are flexibly met.