公开(公告)号：US12130259B2

公开(公告)日：2024-10-29

申请号：US17704081

申请日：2022-03-25

Applicant: Harbin Institute of Technology

Inventor： Jiaxin Li ,  Jiubin Tan ,  Bo Zhao ,  Weijia Shi

IPC: G01N29/07 ,  G01N29/34 ,  G01N29/36 ,  G01N29/46

CPC classification number: G01N29/07 ,  G01N29/34 ,  G01N29/36 ,  G01N29/46 ,  G01N2291/0427

Abstract: The present disclosure proposes a non-baseline on-line stress monitoring system and monitoring method based on multi-mode Lamb wave data fusion. A Lamb wave dispersion curve is established according to geometric dimensions and material parameters of a measured object, a cut-off frequency of a first-order Lamb wave mode is obtained, an excitation frequency of a Lamb wave signal is determined, and then pure Lamb waves in S0 and A0 modes obtained inside the measured object are obtained; an acoustoelastic equation is established, an elastodynamic equation of the measured object under a prestress condition is solved, and linear relationships between a group velocity and a stress of the Lamb waves in the S0 and A0 modes under the excitation frequency are obtained; data is processed through the on-line monitoring system; a stress gradient in a depth direction is calculated, and finally, a stress state of the measured object is represented. The present disclosure does not require data under a zero stress state as baseline data, does not require designing a wedge block capable of generating a critical refraction longitudinal wave, and combines acoustoelastic effects of Lamb waves in different modes to realize online stress monitoring without the baseline data.

公开(公告)号：US20230061816A1

公开(公告)日：2023-03-02

申请号：US17552493

申请日：2021-12-16

Applicant: Harbin Institute of Technology

Inventor： Weijia Shi ,  Bingquan Wang ,  Bo Zhao ,  Jiubin Tan

IPC: G01N29/44 ,  G01N29/06 ,  G01N29/22 ,  G01N29/34

Abstract: The disclosure discloses an air-coupled ultrasonic detection method and device based on a defect probability reconstruction algorithm. The method includes the following steps: determining the excitation frequency of a transmitting air-coupled transducer according to a frequency dispersion curve of guided waves and the thickness of a to-be-detected piece; determining the group velocity of an antisymmetric mode according to the excitation frequency, and determining the inclination angle of the transmitting/receiving air-coupled transducer according to the Snell law; obtaining an initial waveform of a defect-free test piece as reference data by adopting a same-side penetration method, then rotating the transmitting/receiving transducer by 360 degrees by taking the Z direction as an axis at preset angle intervals by adopting a rotary scanning method, collecting N groups of signal data of the to-be-detected piece again, comparing the N groups of signal data with the reference data to determine whether the signal characteristics have great changes or not, calculating the defect distribution probability on the to-be-detected piece, and carrying out defect imaging on a rotating coverage area of the transmitting/receiving air-coupled transducer according to the defect distribution probability. According to the method, the precision of traditional air-coupled ultrasonic X and Y scanning detection is improved, and compared with a complex imaging technology, the air-coupled ultrasonic detection method consumes less time.

公开(公告)号：US09890661B2

公开(公告)日：2018-02-13

申请号：US15118322

申请日：2014-12-26

Applicant: HARBIN INSTITUTE OF TECHNOLOGY

Inventor： Jiubin Tan ,  Chuanzhi Sun ,  Lei Wang ,  Bo Zhao

IPC: F01D25/28 ,  G01B7/31 ,  G01C9/06

CPC classification number: F01D25/28 ,  F01D5/027 ,  F01D25/285 ,  F05D2230/60 ,  F05D2260/83 ,  G01B7/31 ,  G01C9/06 ,  G01C2009/064

Abstract: An aero engine rotor air floatation assembling method and device based on a gantry structure belong to mechanical assembling technology. The present invention can effectively solve the problem of poor coaxality after the aero engine rotor is assembled and has the characteristics of high coaxality after the rotor is assembled, reduced vibration, mounting easiness, high flexibility and improved engine performance. The measuring method and device are: determining rotary reference based on a rotary air bearing; determining the angular positioning of a rotary table according to a grating ruler; extracting the radial error of the radial mounting plane and the inclination error of the axial mounting plane of the rotor based on the four-probe measuring device to obtain the influencing weight of this rotor to the assembled rotor on coaxality; measuring respectively all the rotors required for assembling to obtain the influencing weight of each rotor to the assembled rotor on coaxality; vector optimizing the weight of each rotor to obtain the assembling angle of each rotor.

公开(公告)号：US20230228720A1

公开(公告)日：2023-07-20

申请号：US17704099

申请日：2022-03-25

Applicant: Harbin Institute of Technology

Inventor： Bo Zhao ,  Jiubin Tan ,  Weijia Shi

IPC: G01N29/46 ,  G01N29/04 ,  G01N29/24

CPC classification number: G01N29/46 ,  G01N29/041 ,  G01N29/2437

Abstract: A method, system, device, and medium for online stress monitoring without baseline data based on single-mode multi-frequency signal fusion are provided. The method includes: establishing a dispersion curve according to geometric dimensions and material parameters of a measured object; then solving an approximate linear relationship between propagation time of S0 modes with different frequencies and stress at a fixed propagation distance by using a relationship between stress and group velocity, the obtained linear relationship being an acousto-elastic equation required for final measurement; then performing Hilbert transformation on an obtained signal, extracting a signal envelope, and determining arrival time of two excitation frequency signals by means of a peak extraction algorithm and a time domain width of an excitation signal; and calculating a propagation time ratio and substituting the propagation time ratio into a pre-calibrated acousto-elastic equation to solve a stress value of an object to be measured. The disclosure is advantageous in that the multi-frequency data is fused by using dispersion characteristics of a single-mode Lamb wave and an acousto-elastic effect, thereby achieving online stress monitoring without baseline data.

公开(公告)号：US11630929B2

公开(公告)日：2023-04-18

申请号：US17079428

申请日：2020-10-24

Applicant: HARBIN INSTITUTE OF TECHNOLOGY

Inventor： Bo Zhao ,  Xue Qi ,  Weijia Shi ,  Jiubin Tan

IPC: G06F30/20 ,  G06N3/08 ,  G06F111/10

Abstract: The disclosure provides a linearization identification method for a hysteresis model of piezoceramics based on Koopman operators, and belongs to the field of precision positioning. In order to solve the problem of hysteresis of a piezoelectric actuator in practical application, the disclosure further provides the linearization identification method for the hysteresis model of the piezoceramics based on Koopman operators. The method of the disclosure includes: Step I, building a structure of the hysteresis model of the piezoceramics; Step II, determining parameters of the hysteresis model of the piezoceramics; Step III, obtaining a great amount of simulation data by using simulation software; Step IV, performing deep learning training based on Koopman operators; and Step V, determining a linearization model for the hysteresis model of the piezoceramics based on Koopman operators. The disclosure is applicable to piezoelectric actuator control and precision positioning.