CN-121994392-A - Vibration signal cable force identification method based on angle correction

CN121994392ACN 121994392 ACN121994392 ACN 121994392ACN-121994392-A

Abstract

The invention discloses a vibration signal cable force identification method based on angle correction, which comprises the steps of firstly arranging a hybrid sensor module at the lower end of a cable, wherein the hybrid sensor module comprises an angle sensor and an acceleration sensor, correcting acceleration signals acquired by the acceleration sensor by utilizing angle signals acquired by the angle sensor to obtain corrected acceleration signals, extracting vibration amplitude values and a plurality of orders of frequencies from the corrected acceleration signals, then fitting the vibration amplitude values of corresponding measuring points with an equivalent cable model to obtain initial equivalent effective length, optimizing the initial effective vibration length by a least square method to obtain optimal effective vibration length, and finally calculating cable force based on frequency-cable force calculation.

Inventors

CHEN YUANZHAO
YANG QIWEN
WEN HANBING
LU XIQUAN
LI JIAN
WU WENJUN
LIANG PENG
LIU FENG

Assignees

广西科技大学

Dates

Publication Date: 20260508
Application Date: 20260203

Claims (6)

1. The vibration signal cable force identification method based on angle correction is characterized by comprising the following steps of: s1, arranging at least four mixed sensor modules at the lower end of a inhaul cable, wherein the mixed sensor modules comprise angle sensors and acceleration sensors, and correcting acceleration signals acquired by the acceleration sensors by utilizing angle signals acquired by the angle sensors to obtain corrected acceleration signals corresponding to each measuring point; s2, performing discrete Fourier transform on the corrected acceleration signal to obtain vibration amplitude and a plurality of orders of frequencies of corresponding measuring points; S3, fitting the vibration amplitude of the corresponding measuring point with an equivalent inhaul cable model to obtain the initial effective vibration length of the equivalent inhaul cable model; S4, optimizing the initial effective vibration length by using a least square method to obtain the optimal effective vibration length of the equivalent inhaul cable model; s5, substituting the optimal effective vibration length and the frequencies of the orders into a frequency-cable force calculation formula for calculation to obtain the cable force of the cable.
2. The method for identifying the cable force of a vibration signal based on angle correction according to claim 1, wherein the process of correcting the acceleration signal acquired by the acceleration sensor by using the angle signal acquired by the angle sensor comprises the steps of: S101, acquiring a coordinate transformation matrix from an acceleration sensor to an angle sensor of the hybrid sensor module The calculation formula is as follows: in the formula, Is a three-order identity matrix, The angle sensor is used as a machine body coordinate system for the angle sensor and the acceleration sensor, and tiny angle vectors are arranged among three (x, y and z axes) directions Of (c) wherein , For the numbering of the hybrid sensor modules, Is the first The angle between the angle sensor and the acceleration sensor of each hybrid sensor module in the x-axis direction, Is the first The angle between the angle sensor and the acceleration sensor of each hybrid sensor module in the y-axis direction, Is the first Included angles of the angle sensors and the acceleration sensors of the hybrid sensor modules in the z-axis direction; S102, acquiring a coordinate transformation matrix of an angle sensor and an inertial coordinate system of the hybrid sensor module The calculation formula is as follows: in the formula, Is the first Angle of rotation of the angle sensor of each hybrid sensor module in the Z-axis of the inertial coordinate system (ozz) Is provided with a coordinate transformation matrix of (a), Is the first Angle of rotation of the angle sensor of each hybrid sensor module in the Y-axis of the inertial coordinate system Is provided with a coordinate transformation matrix of (a), Is the first Angle of rotation of the angle sensor of each hybrid sensor module in the Z-axis of the inertial coordinate system Is provided with a coordinate transformation matrix of (a), Is a transposition operation; S103, calculating the total acceleration signal of the acceleration sensor of each hybrid sensor module in an inertial coordinate system The calculation formula is as follows: in the formula, Is the first Acceleration signals acquired by the acceleration sensors of the individual hybrid sensor modules, 、、 The corrected accelerations correspond to the axial directions of the inertial coordinate system X, Y, Z.
3. The method for identifying the cable force of the vibration signal based on the angle correction according to claim 1, wherein the process of fitting the vibration amplitude of the corresponding measurement point with the equivalent cable model comprises the following steps: S301, setting the same effective vibration length and the same virtual hinge position of each order in an equivalent inhaul cable model; S302, constructing a plurality of virtual vibration sensors, wherein the position of each virtual vibration sensor on a guy cable is that The calculation formula is as follows: in the formula, To mix the position of the sensor module on the cable, In order to be able to vibrate in order, Is a virtual hinge position; Taking a high-order vibration mode of an equivalent cable model as a measurement amplitude of the virtual vibration sensor, wherein the high-order vibration mode of the equivalent cable model is a second-order and above vibration mode, and the measurement amplitude of the virtual vibration sensor has a calculation formula as follows: , in the formula, In the equivalent inhaul cable model Position No. The vibration of the order of the vibration, As the amplitude coefficient of the vibration, Is the effective vibration length; S303, normalizing the measured amplitudes of the plurality of virtual vibration sensors into a first-order vibration mode of an equivalent cable model to obtain a first-order vibration mode function of the equivalent cable model, wherein the expression is as follows: in the formula, Is the first to correspond to the equivalent inhaul cable model Any position on the inhaul cable in the order-vibration type function; S304, fitting the vibration amplitude of the corresponding measuring point with a first-order vibration mode function of the equivalent inhaul cable model, and calculating a fitting error, wherein the fitting error function is calculated as follows: in the formula, In order to fit the error values, For the number of hybrid sensor modules, To correspond to the first order vibration amplitude of the measurement point, Is the highest order; s305, determining the initial effective vibration length of the equivalent inhaul cable model based on the calculation result of the fitting error.
4. A vibration signal cable force identification method based on angle correction according to claim 3, wherein the process of optimizing the initial effective vibration length by using least square method comprises: S401, taking the equivalent inhaul cable model parameters corresponding to the initial effective vibration length as input coefficient vectors ; S402, calculating the input coefficient vector by using a least square method Is increased by an increment of (2) Obtaining updated input coefficient vector , ; S403, calculating an updated input coefficient vector Is set for the target function value of (c), the objective function is calculated as: in the formula, For the input coefficient vector to be used, , As a residual vector of the signal, the signal is, , To correspond to the first The maximum amplitude of the order-vibration mode, As a dimension of the dimension, , Fitting errors; S404, iterating the steps S402 and S403 for a plurality of times until the maximum iteration number is reached or the convergence condition is satisfied Wherein Representing the latest generation of fitting amplitude errors, For the previous generation of fitting amplitude errors, Is a tolerance coefficient, which, at this time, The corresponding effective vibration length is the optimal effective vibration length.
5. The vibration signal cable force identification method based on angle correction according to claim 1, wherein the cable force calculation formula of the frequency-inhaul cable is: in the formula, Is the mass per unit length of the inhaul cable, In order to achieve a flexural rigidity, Is used as the cable force of the inhaul cable, Is the frequency.
6. The vibration signal cable force identification method based on angle correction according to claim 1, wherein the hybrid sensor module further comprises a base and a buckle, the angle sensor is detachably arranged on the base through a bolt, and the acceleration sensor is detachably arranged on the base through the buckle.

Description

Vibration signal cable force identification method based on angle correction Technical Field The invention belongs to the technical field of inhaul cable force detection, and particularly relates to a vibration signal cable force identification method based on angle correction. Background In modern large-span engineering structures (such as bridge engineering, power transmission towers and cableways), a guy cable is used as a core force transmission component, the stress state of the guy cable directly determines the safety and stability of the structure, and accurate cable force monitoring and identification are key means for evaluating the health condition of a cable system structure. The frequency method is a non-contact inhaul cable force detection method, extracts natural frequency by collecting vibration signals of inhaul cables, and inverts cable force by combining geometric parameters (length and linear density) of the inhaul cables and boundary conditions, and has the advantages of non-contact/low contact, simplicity and convenience in operation, low cost and capability of long-term online monitoring. Reference 1,Chen C C,Wu WH,Leu M R,et al et al "Tension determination of stay cable or external tendon with complicated constraints using multiple vibration measurements [J].Measureme- Ement,2016, 86:182' provides that the cable vibration mode can be similar to a sine function, each order of vibration mode is fitted through the amplitude (or amplitude ratio) of each measuring point, each order of equivalent cable length (cable effective vibration length) is obtained, and a linear regression algorithm is applied to identify cable force by combining the cable force-frequency relation of the simply supported beam, wherein the cable force identification precision is as high as 3%. However, the method needs to install the sensor at the high side (the side of the high end of the inhaul cable) to ensure the equivalent cable length identification precision, and the difficulty of installing the sensor at the high side is high, so that the method is not easy to popularize and apply. Based on the above, patent number CN2023111400948 discloses a method for identifying the cable force, which realizes the accurate identification of the effective vibration length by a mode of multiple sensors and multiple additional mass working conditions without a high-side sensor. The effect of modeling the fit of the cable vibration in reference 1 is shown in fig. 5, the solid line is the vibration pattern of the equivalent model, the dotted line is the vibration pattern of the cable corresponding to the vibration amplitude measured by the sensor, the effect of modeling the fit of the cable vibration in the CN2023111400948 patent is shown in fig. 6, the solid line is the vibration pattern of the cable corresponding to the vibration amplitude measured by the sensor, the dotted line is the vibration pattern of the equivalent model, when the effective vibration length of the cable is fitted by the equivalent model, the measured vibration amplitudes of the corresponding sensors are all on the same plane, in actual operation, the installation position of each acceleration sensor needs to be repeatedly adjusted to make each acceleration sensor be located on the same plane as much as possible, so that the extracted vibration amplitude value of each measurement point is located on the same plane, however, the surface of the cable is in an irregular shape, when the cable is installed, it is difficult to ensure that each acceleration sensor is on the same plane, angle deviation exists between each acceleration sensor, so that the amplitude of the acceleration sensor normalized on the same plane deviates from the actual amplitude, for example, the actual amplitude values corresponding to the acceleration sensor A and the acceleration sensor B are 1, but because the angle deviation exists between the acceleration sensor A and the acceleration sensor B, the amplitude value corresponding to the acceleration sensor B may become 1.1 or 0.9 when the cable is fitted, the amplitude of a measuring point does not meet the sine curve (the vibration mode of an equivalent cable model), and the equivalent cable model is difficult to obtain the accurate effective vibration length (equivalent cable length) and virtual hinge position, so that the accuracy of calculation of the cable force of the subsequent cable is reduced. Disclosure of Invention The invention aims to provide a vibration signal cable force identification method based on angle correction, which is characterized in that an acceleration sensor of a hybrid sensor module is used for collecting acceleration signals when a cable vibrates, an angle sensor is used for collecting vibration angle signals when the cable vibrates, and the acceleration signals are corrected through the vibration angle signals, so that the acceleration signals of each hybrid sensor are on the same plane, the amplitudes