9 results about "Acceleration amplitude" patented technology

The application discloses a kind of acceleration amplitude uniformity optimization methods for vertical vibration platform table, including steps: based on the principle of deflection distribution, define initial attachment point position;Define the working table boundary range;Simulation analysis is carried out to number module, and the distribution data of uniformity is obtained, and whether the uniformity of excellent area within boundary can be made to be larger is analyzed by comparing working boundary range;In the case where the structural stiffness is fixed, the only method to reduce the acceleration amplitude deviation between two points is to reduce the distance between two points;Repeat the above steps, so that the uniformity within working boundary reaches design target.The application aims to improve the acceleration amplitude uniformity of vibration platform extension table by increasing the number of excitation arm and table attachment points, so that the acceleration amplitude uniformity of the table is greatly improved.

This invention relates to the field of speech enhancement technology, and more particularly to a speech enhancement method and system. The invention obtains the orientation quaternion of the target device at each moment based on the rotational angular velocity of the target device at each moment and the acceleration amplitude of the original acceleration signal at each moment; based on the orientation quaternion of the target device at each moment, the coordinate system of the acceleration amplitude of the original acceleration signal at each moment is rotated to the global reference coordinate system to obtain the attitude-normalized acceleration amplitude of each moment, forming the attitude-normalized acceleration signal; a noise reduction mask and a speaker-specific mask are fused to obtain a fusion mask; based on the fusion mask and audio features, residual enhancement is performed on the spectrogram of the speech audio to be enhanced to obtain the enhanced spectrogram; based on the phase spectrum of the speech audio to be enhanced and the enhanced spectrogram, the enhanced speech audio waveform is obtained. This invention effectively improves the speech enhancement effect.

The invention relates to the technical field of speech enhancement, in particular to a speech enhancement method and system. The method comprises the following steps: acquiring an azimuth quaternion of a target device at each moment based on a rotation angular velocity of the target device at each moment and an acceleration amplitude of an original acceleration signal at each moment; based on the azimuth quaternion of the target equipment at each moment, rotating a coordinate system of an acceleration amplitude of each moment in the original acceleration signal to a global reference coordinate system to obtain an acceleration amplitude after attitude normalization at each moment, and forming an acceleration signal after attitude normalization; fusing the noise reduction mask and the speaker specific mask to obtain a fused mask; based on the fusion mask and the audio features, performing residual enhancement on the spectrogram of the to-be-enhanced voice audio to obtain an enhanced spectrogram; and obtaining an enhanced voice audio waveform based on the phase spectrum of the to-be-enhanced voice audio and the enhanced spectrogram. According to the invention, the speech enhancement effect is effectively improved.

The application relates to the field of helicopter structure strength design, in particular to a fatigue stress calculation method based on helicopter structure vibration. The method comprises the following steps: performing frequency spectrum analysis on the time domain data of vibration measuring points on the body to obtain the frequency response results at typical vibration measuring points; determining the main damage frequency and acceleration amplitude of the main damage of the structure according to the frequency response results at the typical vibration measuring points; determining the structural natural modal frequency closest to the main damage frequency and the working modal corresponding to the structural natural modal as the working modal under the main damage frequency based on the main damage frequency and in combination with the finite element modal analysis results of the body; taking the measuring point as the reference, performing equivalent displacement analysis according to the acceleration amplitude and the working modal mode, and converting the acceleration amplitude into equivalent displacement distribution and direction under the condition that the phase angle of the working modal mode is kept unchanged; and performing equivalent stress calculation according to the equivalent displacement distribution and direction and the finite element model of the structure to obtain the static stress.

The invention belongs to the technical field of ballistic target tests, and discloses a ballistic target test model acceleration measurement data correction method. The ballistic target test model acceleration measurement data correction method comprises the following steps: carrying out a ballistic target test model acceleration measurement test; carrying out ballistic target test model acceleration measurement data integration processing; comparing the test model motion velocity peak value with the test model launching initial velocity measurement value; and correcting an acceleration measurement data error of the ballistic target test model. The method for correcting the acceleration measurement data of the ballistic target test model is suitable for extreme overload acceleration environments such as ballistic target tests and artillery tests with the acceleration amplitude being tens of thousands of gravitational accelerations and the short duration being ten milliseconds.

This invention provides a method and system for estimating the IMU mounting angle based on an exponential decay function. The method includes: establishing a gyroscope zero-bias estimation model for the vehicle and an accelerometer-gravity projection correlation model in a stationary state; calculating the effective acceleration using an exponential decay function to suppress acceleration amplitudes during cornering, performing trajectory recursion only during straight-line acceleration to obtain the horizontal displacement; calculating the heading mounting angle at each epoch using the displacement vector direction, filtering candidate heading mounting angles using consecutive adjacent angle differences, and verifying the candidate heading mounting angle results through inertial navigation recursion. This invention calculates the roll and pitch mounting angles when stationary and the heading mounting angle through acceleration during motion, achieving integrated estimation of the three mounting angles. It is suitable for initial calibration scenarios of vehicle-mounted inertial navigation, requires no external references such as GNSS or odometers, and acceleration is not limited to the stationary-to-start phase, significantly simplifying the implementation conditions for mounting angle calibration.

This invention belongs to the field of ballistic target testing technology and discloses a method for correcting acceleration measurement data of a ballistic target test model. The method includes conducting an acceleration measurement experiment on the ballistic target test model; performing integral processing of the acceleration measurement data; comparing the peak velocity of the test model with the measured initial velocity; and correcting errors in the acceleration measurement data. This method is applicable to extreme overload acceleration environments such as ballistic target tests and artillery tests, where the acceleration amplitude is tens of thousands of gravitational accelerations and the duration is on the order of tens of milliseconds.

The invention discloses an IMU (inertial measurement unit)-based gait segmentation method, which relates to the technical field of motion analysis, and comprises the following steps: processing three-axis acceleration data acquired by an IMU, extracting an acceleration amplitude, and recognizing a gait cycle based on the acceleration amplitude; dynamically updating a plurality of dynamic parameters related to gait event detection based on the gait cycle and the three-axis acceleration data; based on the dynamic parameters, identifying a plurality of key events in the gait cycle, including a starting point, an ending point, a departure point and a landing point; and outputting a complete gait event sequence for gait analysis. According to the method, high-precision gait segmentation is realized through motion state adaptive judgment, gait cycle detection and dynamic parameter updating, and the motion analysis precision of the wearable equipment is remarkably improved.

The invention belongs to the technical field of mechanical dynamics, and discloses a pipeline system dynamics modeling method considering hoop degradation. The excitation frequency and the excitation amplitude are considered, a degradation test under fixed-frequency excitation is conducted on the hoop, the change rule of the resonance frequency and the resonance acceleration amplitude of the hoop-mass rod system is obtained through a frequency sweeping test, and the degraded hoop with the corresponding cycle index is selected according to the rule and installed on the L-shaped pipeline for subsequent tests; based on a test result, a parameter identification method and a polynomial fitting method are adopted to establish a characterization model that the resonance frequency, the resonance response amplitude, the rigidity coefficient and the damping coefficient change along with the cycle index, and the mechanical property degradation characterization of the metal rubber hoop is perfected. The method has important theoretical significance and engineering application value for improving the reliability and durability of an aircraft pipeline system.