Method and device for acquiring non-contact detection position and posture of pulsed eddy current probe

Abstract

The invention provides a method and device for acquiring the non-contact detection position and posture of a pulsed eddy current probe. The method comprises the following steps: S1, deploying a coordinate system; s2, processing data acquired by the optical locator through a visual algorithm; s3.1, the initial coordinates are obtained; s3.2, the correction value is calculated; s3.3, the posture is calculated; s4, obtaining the filtered data; s5, the integrated coordinates are obtained; and S6, respectively solving a variance and a mean value of the integrated coordinate and the filtered coordinate, integrating the two pieces of data, solving the weight k of the two pieces of data, and obtaining the final coordinate. The device comprises a first shell, a second shell, a pulsed eddy current probe, an optical locator and a steering engine. The pulsed eddy current probe is located between the first shell and the second shell, and the optical locator is arranged on the other side of the first shell and externally connected with the steering engine. According to the method and the device, the position and the posture of the pulsed eddy current probe relative to the detected component can be obtained, and the spatial orientation of the detected area can also be obtained.

Description

Technical Field

[0001] The invention relates to the field of space positioning, and in particular to a method and a device for obtaining a non-contact detection position and posture of a pulsed eddy current probe. Background Art

[0002] Pulse eddy current detection technology is a branch of eddy current detection technology. This technology uses a rectangular wave voltage to load the excitation coil in the probe. In the high-level section of the rectangular wave voltage, the excitation coil generates a primary magnetic field that penetrates the covering layer and acts on the metal component; when the rectangular wave voltage changes from a high level to a low level, the primary magnetic field decreases sharply. According to the Faraday effect, eddy currents will be induced in the metal component. At the same time, according to the Oersted effect, eddy currents will generate a magnetic field, which is generally called a secondary magnetic field. Since the eddy currents are induced, they continue to dissipate downward and outward. This dissipation process is related to the electromagnetic parameters (conductivity, magnetic permeability, etc.) and geometric parameters (size, etc.) of the metal component, and will also be reflected in the change of the secondary magnetic field. The secondary magnetic field that penetrates the covering layer is converted into a voltage signal through the receiving coil or magnetic sensitive element in the probe, and then the voltage signal is analyzed to obtain relevant information about the metal component. Since the magnetic field has good penetrability and for rectangular wave excitation, when the average power remains unchanged, the instantaneous power can be increased by reducing the repetition frequency, duty cycle, and increasing the amplitude to increase the primary magnetic field strength, thereby increasing the secondary magnetic field strength. Therefore, the pulsed eddy current probe can realize the detection of metal components with covering layers in a non-contact manner.

[0003] For example, Chinese invention patent 202410267991.3 discloses a pulse eddy current scanning and detection device for in-service pipelines. The device is installed around the pipeline and can carry a pulse eddy current probe to detect the pipeline in the circumferential and axial directions. However, if the surface of the pipeline is uneven due to pits, rust, weld excess height, etc., the device may easily cause the pulse eddy current probe to deflect, that is, it is difficult to ensure that the opening direction of the coil in the pulse eddy current probe is always perpendicular to the surface of the pipe body, and the scheme of this invention patent fails to obtain the deflection of the pulse eddy current probe relative to the inspected pipeline; for example, Chinese utility model patent ZL202021960940.2 discloses a continuous scanning eddy current probe tooling, which obtains the scanning distance by an encoder close to the inspected workpiece, and also requires that the surface close to the inspected workpiece must not be uneven, and fails to obtain the deflection of the pulse eddy current probe relative to the inspected pipeline; for example, Chinese invention patent ZL201610931272.2 discloses a pulse eddy current positioning detector, which achieves precise positioning of the moving trajectory of the detection equipment by adding a locator similar to a photoelectric mouse to the pulse eddy current detection equipment. However, a positioning instrument similar to an optical mouse not only has high requirements on the surface flatness of the workpiece to be inspected, and is difficult to use for workpieces with larger curvature (such as pipes), but also requires that the surface roughness of the workpiece to be inspected be within a certain range, and is difficult to use for surfaces that are too rough (such as those with rust) or too smooth (such as those that have been polished or chrome-plated); Chinese utility model patent ZL202121009017.5 discloses a pulsed eddy current detection probe fixing device with a positioning function, which can adjust and lock the horizontal rotation angle and pitch angle of the pulsed eddy current detection probe to implement multi-angle detection. However, when implementing pulse detection, the device fails to obtain the position and posture of the probe relative to the object being tested; for example, Chinese invention patent 202410448049.7 discloses a high-resolution pulsed eddy current probe and signal processing method, which obtains the displacement data of the probe (including the relative position and angle of the probe) by installing an IMU (Inertial Measurement Unit) sensor in the pulsed eddy current probe, and processes the pulsed eddy current detection signal in combination with the displacement data of the probe to achieve accurate detection and positioning of tiny defects on the surface or inside of the target to be tested, thereby improving the resolution of the pulsed eddy current technology. However, in the scheme of this invention patent, it is difficult to avoid cumulative errors in the probe displacement data obtained based on the accelerometer and gyroscope in the IMU sensor. Generally, the farther away from the initial position of the probe, the greater the error in the displacement data, and the displacement data is relative to the initial position of the probe, not relative to the object being tested.

[0004] In summary, the existing scheme does not obtain the position and posture of the pulsed eddy current probe relative to the inspected component, which is not only not conducive to the correction of the test results, but also difficult to improve the detection accuracy and the detection rate of local defects such as pits and cracks. It is also not conducive to judging whether the current test results are valid and marking the position of the test results, making it difficult to provide accurate guidance for subsequent processing.

[0005] Therefore, with the support of the National Natural Science Foundation Youth Project "Research on the Mechanism and Method of Pulse Eddy Current Detection of Local Defects of Non-ferromagnetic Metal Components with Coating Layers" (62003056), it is necessary for technical personnel in this field to provide a method and device for obtaining the non-contact detection position and posture of a pulse eddy current probe to solve the above-mentioned technical problems. Summary of the invention

[0006] The present invention provides a method and device for obtaining the non-contact detection position and posture of a pulsed eddy current probe, which solves the problem of not obtaining the position and posture of the pulsed eddy current probe relative to the inspected component, which is not conducive to correcting the detection results, improving the detection accuracy and the local defect detection rate, and is not conducive to judging the validity of the detection results and marking the result position, and cannot provide accurate guidance for subsequent processing.

[0007] In order to solve the above technical problems, the present invention provides a method and device for obtaining the non-contact detection position and posture of a pulsed eddy current probe, including:

[0008] In order to solve the above problems, the present invention also provides a method for obtaining the non-contact detection position and posture of a pulsed eddy current probe, comprising the following steps:

[0009] include:

[0010] S1. Deploy narrow pulse locators to establish a coordinate system of the object to be measured, and obtain the initial coordinates and posture of the pulsed eddy current probe according to the spatial position relationship between each narrow pulse locator;

[0011] S2. Process the data obtained by the optical locator through a visual algorithm to calculate the correction value of the relative spatial position between the probe and the object to be measured; electrically connect the narrow pulse locator installed on the object to be measured to the battery and the PC end, and electrically connect the optical locator to the PC end to achieve the effect of returning the obtained initial value coordinates, posture, and correction value to the PC end;

[0012] S3.1. A narrow pulse positioning medium is sent between the narrow pulse locator on the measured object and each of the narrow pulse locators, and the distance between each narrow pulse locator is calculated using the speed of the pulse and the time required for a round trip to obtain the initial coordinates;

[0013] S3.2, the optical positioner calculates the correction value according to the algorithm, and the correction value includes the offset distance of the pulsed eddy current probe relative to the object to be measured in the vertical direction and the horizontal direction;

[0014] S3.3, the narrow pulse locator integrates a posture detection module, calculates the posture, and returns the posture and the initial coordinates to the PC end;

[0015] S4, after returning the initial coordinate data to the PC end, filtering the first several groups of the initial coordinate data to obtain filtered data;

[0016] S5. Based on the filtered data, add the correction value to the horizontal and vertical coordinate values ​​to obtain the integrated coordinates;

[0017] S6. Calculate the variance and mean of the integrated coordinates and the filtered coordinates respectively, integrate the two data to calculate the weight k of the two, and obtain the final coordinates to reduce the impact of the obstacle blocking the signal; when the weight shows obvious deviation, the PC will display a warning.

[0018] Preferably, S1 includes:

[0019] The number of the narrow pulse locators is ≥ 5, and the height difference between at least one of the narrow pulse locators and the other narrow pulse locators in the vertical direction is [0.30m, 20.00m], and the interval between the labels in the horizontal direction is [0.20m, 8.00m]. One narrow pulse locator is provided on the pulse eddy current probe; one narrow pulse locator is provided above the object to be measured.

[0020] Preferably, filtering the acquired initial coordinate data in S4 includes:

[0021] The initial coordinate data is returned to the PC, and the previous groups of initial coordinate data are integrated into a linear relationship to predict the next group of initial coordinate data. The weights are then solved based on the variance relationship between the predicted values ​​and the actual values ​​to obtain the filtered data.

[0022] Preferably, in S5, the correction value is combined with the filtered data to obtain the integrated coordinates:

[0023] Based on the filtered data, the correction value is added to the horizontal and vertical coordinate values ​​to obtain the integrated coordinates.

[0024] Preferably, in S6, weighting the integrated coordinates and the filtered coordinates and integrating them to obtain the final coordinates comprises:

[0025] The variance and mean of the integrated coordinates and the filtered coordinates are calculated respectively, and the two data are integrated to calculate the weight k of the two, so as to obtain the final coordinates, so as to reduce the influence of the obstacle blocking the signal;

[0026] When calculating k, if k>0.85 or k<0.15, we mark the coordinate status at this time as unreliable, display an early warning on the PC, and the staff checks the working status and working temperature of the equipment. Preferably, the specific steps for obtaining the filtered data in S4 are:

[0027] S4.1. The signal returned by the narrow pulse locator to the PC can be listed as The form of A is the mean of the returned signal, σ A is the variance, is the predicted value relationship for the next second, where μ B is the mean of the predicted values, σ B is the variance of the predicted value.

[0028] X B , X A Putting it all together, we list the formula where kX A is the weight, (1-k) is X B The weight, is the required signal value after calculation to eliminate the burr;

[0029] S4.2. Integrate it into in is the variance of the whole formula. When the variance is minimum, the weight k is calculated.

[0030] The derivation yields

[0031] The relationship can be expressed as

[0032] S4.3.

[0033] The mean of the integration into The variance is integrated into At this time we order We can Therefore, we receive the mean signal μ at this moment A , we can quickly predict the next signal μ B , and then calculate the weights of these two values ​​according to the relationship between their variances, and finally obtain the filtered data

[0034] Preferably, the specific steps of S6 are:

[0035] S6.1. List the corrected coordinates as The filtered data is where μ A μ B is the coordinate signal mean, σ A σ B is the variance of the two sets of data;

[0036] S6.2. Integrate the two sets of data into Where k is the weight of correcting the coordinate data, The final coordinates obtained after calculation are written as

[0037] S6.3. Calculate the final coordinate value when the variance is minimum, and construct the function from the variance formula

[0038] The derivation yields It can be written as Simplify the mean into The variance is simplified to This time Available The data is processed and the final coordinates are obtained. When performing S6, if k>0.85 or k<0.15, we will mark the coordinate status at this time as unreliable and display an early warning on the PC. At the same time, the staff should check each narrow pulse locator and optical locator.

[0039] The device for obtaining the non-contact detection position and posture of the pulsed eddy current probe comprises:

[0040] A first housing for protecting the pulsed eddy current probe;

[0041] A second housing for protecting the pulsed eddy current probe, which is arranged opposite to the first housing, and the second housing is arranged on one side of the first housing;

[0042] A pulsed eddy current probe, wherein the pulsed eddy current probe is arranged between the first shell and the second shell;

[0043] An optical positioner, which is arranged on the other side of the first housing, and a steering gear is arranged inside the optical positioner;

[0044] A narrow pulse locator, the narrow pulse locator being arranged on the top of the first housing;

[0045] A battery, wherein the battery is disposed inside the first housing;

[0046] A battery cover is arranged on the top of the first housing.

[0047] Preferably, the battery cover is located on the top of the tag battery, and the battery and the narrow pulse locator are electrically connected.

[0048] Preferably, a threaded ring is fixedly installed inside the battery cover, an inner side surface of the threaded ring is threadedly connected with an abutment column, a pressure plate is provided at the bottom of the abutment column, a rubber pad is fixedly installed at the bottom of the pressure plate, and a groove is provided at the top of the abutment column; the bottom of the abutment column is rotatably connected with a connecting column, and the bottom of the connecting column is fixedly installed on the top of the pressure plate.

[0049] Compared with the related art, the method and device for obtaining the non-contact detection position and posture of the pulsed eddy current probe provided by the present invention have the following beneficial effects:

[0050] The present invention provides a method and device for obtaining the non-contact detection position and posture of a pulsed eddy current probe, which can not only obtain the position and posture of the pulsed eddy current probe relative to the inspected component, but also obtain the spatial orientation of the inspected area, which is not only conducive to the correction of the detection result, improving the detection accuracy and the detection rate of local defects such as pits and cracks, but also conducive to judging whether the current detection result is valid and marking the position of the detection result, thereby providing accurate guidance for subsequent processing.

[0051] This method and device can not only accurately obtain the position and posture of the pulsed eddy current probe relative to the inspected component, but also the spatial orientation of the inspected area where the pulsed eddy current probe is located. This comprehensive information acquisition is not only conducive to correcting the test results, improving the test accuracy and the detection rate of local defects such as pits and cracks, but also helps to verify the validity of the current test results, mark the test result location, and provide accurate guidance for subsequent processing.

[0052] In terms of structural design, the probe shell is made of ABS material, which will not affect the primary magnetic field emitted by the probe and the secondary magnetic field received by the probe. The entire binocular camera is connected by a servo. When working, the camera can be adjusted according to the image returned by the camera at any time to keep the image flush with the pipeline, so as to more accurately measure the relative position of the probe and the pipeline.

[0053] In terms of data processing, each narrow pulse locator sends a narrow pulse positioning medium to each other, calculates the distance between each other, and calculates the spatial position of the tag through the three-sphere algorithm. At the same time, a base station is placed on the pipeline, and a coordinate system is established with it as the origin to link its spatial position with the relative position of the pipeline. The optical locator calculates the position of the entire pipeline probe relative to the pipeline through the texture light and corrects the coordinates. The filtered and corrected coordinates are then combined, and the final coordinates are obtained through weight integration and displayed on the PC. This coordinate integration method makes the spatial position between the probe and the pipeline more accurate, better helps the signal to multiply and find pipeline defects. The collected coordinate data is filtered twice, which effectively reduces the data noise caused by the pipeline blocking the signal and improves the accuracy and reliability of the detection. When the probe is out of the visual range or the pipeline blocks the line of sight, resulting in a large weight deviation, the host computer will issue an alarm and discard the data with excessive weight until the weight returns to normal before continuing to display the coordinates on the host computer to ensure the reliability and continuity of the detection process.

[0054] In the specific implementation process, because the pulse realizes the detection of metal components with covering layers in a non-contact manner, the returned result signal will be affected by the posture and angle of the sensor during the detection process. Knowing the precise spatial position of the sensor and its posture angle is conducive to signal propagation and more accurate detection of pipeline defects based on the position and angle of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A flowchart of a method for obtaining a pulsed eddy current probe for non-contact detection of position and posture;

[0056] Figure 2 for Figure 1 A schematic diagram of the structure of the device corresponding to the method;

[0057] Figure 3 for Figure 2 The left structural diagram shown;

[0058] Figure 4 for Figure 2 The schematic diagram of the top view structure shown;

[0059] Figure 5 for Figure 2 The three-dimensional structure diagram shown;

[0060] Figure 6 for Figure 5 Another perspective structural schematic diagram shown;

[0061] Figure 7 for Figure 5 A schematic diagram of a cross-sectional structure of a first shell shown;

[0062] Figure 8 for Figure 5 The schematic diagram of the cross-sectional structure of the optical positioner shown;

[0063] Fig. 9 A schematic diagram of establishing a coordinate system with a base station on a pipeline as the origin provided by the present invention;

[0064] Fig.10 A schematic diagram of the viewing angle rotation effect of the optical locator provided by the present invention;

[0065] Fig.11 A schematic diagram of establishing a coordinate system with the optical locator as the origin provided by the present invention;

[0066] Fig.12 A schematic diagram of calculating the horizontal offset value of the optical positioner provided by the present invention,

[0067] Fig.13 A schematic diagram of the binocular camera distance measurement principle provided by the present invention;

[0068] Fig.14 A schematic diagram of calculating the vertical offset value of the optical positioner provided by the present invention;

[0069] Fig.15 A schematic axonometric diagram of circular surface positioning performed by multiple base stations provided by the present invention;

[0070] Fig.16 A schematic top view of circular surface positioning performed by multiple base stations provided by the present invention;

[0071] Fig.17 A left view showing circular surface positioning performed by multiple base stations provided by the present invention;

[0072] Fig.18 for Figure 2 A schematic structural diagram of a second embodiment of the device;

[0073] Fig.19 for Fig.18 Another perspective structural schematic diagram shown;

[0074] Fig. 20 It is a schematic diagram of the device structure mentioned in the first embodiment;

[0075] Fig.21 Schematic diagram of the device structure mentioned in the second embodiment.

[0076] Numbers in the figure: 1. Pulse eddy current probe, 2. Narrow pulse locator, 3. Optical locator, 31. Servo, 4. First shell, 5. Battery, 6. Second shell, 7. Battery cover, 8. Threaded ring, 81. Abutment column, 82. Groove, 83. Connecting column, 84. Pressure plate, 85. Rubber pad, 9. UWB locator, 10. Narrow pulse ultrasonic locator, 11. LiDAR, 12. Binocular camera. DETAILED DESCRIPTION

[0077] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0078] First embodiment

[0079] Please refer to Figure 1-Figure 17 and Fig. 20 In order to solve the above problems, the present invention provides a method for obtaining a pulsed eddy current probe non-contact detection position and posture device, comprising the following steps:

[0080] S1. First, deploy UWB locators 9 to establish a coordinate system of the object to be measured. The UWB locators 9 are a type of narrow pulse locators. The number of UWB locators 9 is greater than or equal to 4, and at least one of the UWB locators 9 has a height difference of not less than 30 cm and not more than 20 m with other UWB locators 9 in the vertical direction. The interval between the UWB locators 9 in the horizontal direction should be not less than 20 cm and not more than 8 m. There is also one UWB locator 9 installed on the pulse eddy current probe.

[0081] At the same time, there must be a UWB locator 9 installed above the pipeline;

[0082] S2. Process the data acquired by the binocular camera 12 through a visual algorithm to calculate the correction value of the relative spatial position between the probe and the object to be measured. The binocular camera 12 is a type of optical locator 3. The UWB locator 9 installed on the object to be measured is electrically connected to the battery and the PC end, and the binocular camera 12 is electrically connected to the PC end to achieve the effect of returning the acquired initial coordinates, posture, and correction values ​​to the PC end;

[0083] S3.1, the UWB locator 9 on the measured object sends a signal to each of the UWB locators 9, and the distance between the base station and the tag is calculated using the speed of signal transmission and the time required for a round trip to obtain the initial coordinates of the pulsed eddy current probe;

[0084] S3.2, the binocular camera 12 calculates the correction value according to the algorithm, and the correction value includes the offset distance of the pulsed eddy current probe relative to the object to be measured in the vertical direction and the horizontal direction;

[0085] S3.3, the UWB locator 9 integrates a posture detection module, which calculates the posture and the initial coordinates and returns them to the PC end;

[0086] S4, after returning the initial coordinate data to the PC, a linear equation is listed according to the previous groups of initial coordinate data, the next group of initial coordinate data is predicted, and then the weight is solved according to the variance relationship between the predicted value and the actual value to obtain the filtered data;

[0087] S5. Based on the filtered data, add the correction value to the horizontal and vertical coordinate values ​​to obtain the integrated coordinates;

[0088] S6, respectively calculate the variance and mean of the integrated coordinates and the filtered coordinates, integrate the two data to calculate the weight k of the two, and obtain the final coordinates, so as to reduce the impact of the obstacle blocking the signal;

[0089] S7. When there is an obvious deviation in the weight, a warning will be displayed on the PC.

[0090] In the S1, a base station must be placed on the pipeline, and the base station is taken as the origin, the plumb line is taken as the Z axis, the vertical pipeline center line and the plumb line are taken as the Y axis, and the axis parallel to the pipeline center line is taken as the X axis.

[0091] As attached Fig. 9 As shown, when arranging base stations, the best positioning effect is achieved when the distance between base stations is kept within the range of 30cm-20m. At the same time, at least one base station has a height difference of 20cm-8m with the other three, otherwise three-dimensional positioning is impossible.

[0092] As attached Figure 6 As shown, the coordinate data obtained by the final positioning tag and the correction value calculated by the binocular camera 12 will be directly returned to the PC end, and the three-dimensional positioning trajectory will eventually be displayed on the PC end, the axonometric view of the pulsed eddy current probe 1;

[0093] The distance calculation formula in S3.1 is:

[0094] d=c×Δt / 2

[0095] Where d is the distance between each UWB locator 9, in mm; c is the speed of light, which is 3×10 8 km / s; Δt is the time difference between the tag sending and receiving signals, in seconds.

[0096] Then according to the distance between each UWB locator 9 As the radius, take the center of each base station as the center of the sphere, and make a sphere. The effect is as shown in the attached figure. Fig.15 as shown.

[0097] Assume that the coordinates of the UWB locator 9 under test are T(x, y, z), and the coordinate positions of each UWB locator 9 are A i (x i ,y i , z i ) where i = 1, 2, 3, ..., n, then

[0098]

[0099] The spatial distance between the UWB locators 9 can be expressed as

[0100]

[0101] The coordinates T (x, y, z) of the UWB locator 9 under test are solved, and what is obtained at this time is the initial coordinates of the UWB locator 9 under test.

[0102] When the visual algorithm in S3.2 is executed, the texture light in the binocular camera 12 will be turned on to prevent calculation errors caused by the light source being blocked by the pipeline in the pipe gallery environment;

[0103] The correction principle of the binocular camera 12 is to use the line connecting the binocular camera 12 and the center of the pipe cross section as the x-axis, and the position perpendicular to the y-axis and parallel to the pipe interface as the x-axis, and assist the UWB locator 9 in the x- and y-axis directions to perform spatial coordinate positioning on the pulsed eddy current probe 1 as shown in the attached figure. Fig. 9 As shown, because the binocular camera 12 is externally connected to a steering engine 31, the binocular camera 12 lens will be rotated to a horizontal position flush with the pipe gallery in the camera's viewing angle according to the image captured by the camera, as shown in the attached Fig.10 As shown;

[0104] The principle of auxiliary positioning in the x direction is to record the two camera imaging points of the binocular camera 12 as L With O R , the distance between the imaging point and the lens is recorded as f, the distance between the imaging point and the point to be measured is Z, and then the highest point of the highest cross-section of the calibrated corridor is calibrated as the calibration point P. In the binocular camera 12 viewing angle, the offset distance between the calibration point and the central axis in each viewing angle is respectively set as u1 and u2. u1 and u2 are calculated as the actual distance according to the number of pixels offset from the central axis. Then, the distance between the calibration points of the left and right viewing angles is calculated by L=b-u1-u2. The distance between the two imaging points is b, where b can be measured when the camera is installed, as shown in the attached figure. Fig.12 , 13 As shown;

[0105] According to the similarity theorem, we can deduce Thus, Z is calculated. Thus, the offset distance of the binocular camera 12 in the x direction can be calculated;

[0106] The principle of auxiliary positioning in the y direction is to first find a suitable position and cover the lower half of the binocular camera 12 with the pipe as shown in the attached figure. Fig.14 As shown, the distance from the upper left corner of the camera's view to the top of the pipe is y1, and the distance from the upper left corner of the camera's view to the bottom of the pipe is y2. y1 and y2 can be calculated by the number of pixels, (y1+y2) / 2=y3, where y3 is the center line of the pipe. At this time, the offset of the binocular camera 12 on the y axis is H1. a can be calculated, where a is the correction coefficient in the y direction. After that, the deviation distance of the binocular camera 12 in the y direction can be calculated according to the pipeline centerline position y3 in the camera's viewing angle. The offset distance is set as △y;

[0107] When the pipe diameter is too large and exceeds the entire camera range, the binocular camera 12 will calculate the pipe diameter according to the offset degree of the texture light pattern, and then repeat the above method to calculate the offset distance.

[0108] The x and y direction offset distances obtained in the above process are the correction values.

[0109] The steps of posture calculation in S3.3 are as follows:

[0110] The first step is to define the initial quaternion values ​​as q0=1, q1=0, q2=0, q3=0.

[0111] The second step is to read the accelerometer value and angular velocity value. The program defines variables ax, ay, az, gx, gy, and gz respectively. The gyroscope value is converted into radians. The conversion is as follows: 1 degree = 0.0174 radians.

[0112] The third step is to extract the gravity components q0, q1, and q2 in the attitude matrix, and obtain the mathematical formula:

[0113]

[0114] Then the gravity component in the probe coordinate system is extracted as

[0115]

[0116] The fourth step is to find the attitude error. Perform a cross product of the two vectors (define ex, ey, ez as the three axis error elements). The mathematical calculation is:

[0117] The fifth step is to input the error into the PID controller and add it to the angular velocity measured by the gyroscope to correct the angular velocity value. Kp is the complementary filter coefficient, and here Kp=0.5

[0118] gx = gx + Kp *ex+ accex ;

[0119] gy = gy + Kp * ey + accey

[0120] gz = gz + Kp * ez + access

[0121] The sixth step is to solve the quaternion differential equation. The mathematical calculation is as follows: the initial values ​​q0 = 1, q1 = 0, q2 = 0, q3 = 0, w x , w y , w z is the angular velocity and Δt is the cycle time.

[0122]

[0123] The seventh step is quaternion normalization. The normalization method is the same as the acceleration normalization method.

[0124] recipNorm=invSqrt(q0*q0+ql*ql+q2*q2+q3*q3);

[0125] q0=q0*recipNorm;

[0126] ql = ql * recipNorm;

[0127] q2 = q2 * recipNorm;

[0128] q3 = q3 * recipNorm;

[0129] The eighth step is to calculate the attitude angle. The mathematical formula is:

[0130]

[0131] The corresponding elements of the two matrices are equal, so

[0132] g1=2(q1q3-q0q2), g2=2(q2q3+q0q1)

[0133] g3=q0 2 -q1 2 -q2 2 +q3 2 , g4=2(q1q2+q0q3)

[0134] g5=q0 2 +q1 2 -q2 2-q3 2

[0135] Then we get

[0136] γ=-arcsin(g1)

[0137] θ=arctan(g2 / g3)

[0138] ψ=arctan(g4 / g5).

[0139] The specific steps of obtaining the filtered data in S4 are:

[0140] S4.1, the signal returned by UWB locator 9 to the PC can be listed as The form of A is the mean of the returned signal, σ A is the variance, is the predicted value relationship for the next second, where μ B is the mean of the predicted values, σ B is the variance of the predicted value.

[0141] X B , X A Putting it all together, we list the formula where kX A is the weight, (1-k) is X B The weight, is the required signal value after calculation to eliminate the burr;

[0142] S4.2. Integrate it into in is the variance of the whole formula. When the variance is minimum, the weight k is calculated.

[0143] The derivation yields

[0144] The relationship can be expressed as

[0145] S4.3.

[0146] The mean of the integration into

[0147] The variance is integrated into At this time we order We can Therefore, we receive the mean signal μ at this moment A , we can quickly predict the next signal μ B, and then calculate the weights of these two values ​​according to the relationship between their variances, and finally get the filtered coordinates

[0148] The specific steps of S6 are:

[0149] S6.1. List the corrected coordinates as The filtered coordinates are listed as where μ A μ B is the coordinate signal mean, σ A σ B is the variance of the two sets of data;

[0150] S6.2. Integrate the two sets of data into Where k is the weight of correcting the coordinate data, The final coordinate data obtained after calculation is written as

[0151] S6.3. Calculate the final coordinate value when the variance is minimum, and construct the function from the variance formula

[0152] The derivation yields It can be written as Simplify the mean into The variance is simplified to This time Available The data is processed and the final coordinate data is obtained.

[0153] When performing S6, if k>0.85 or k<0.15, we mark the coordinate status at this time as unreliable and display a warning on the PC.

[0154] The device for obtaining the non-contact detection position and posture of the pulsed eddy current probe comprises:

[0155] A first housing 4;

[0156] a second housing 6, wherein the second housing 6 is disposed on one side of the first housing 4;

[0157] A pulsed eddy current probe 1, wherein the pulsed eddy current probe 1 is arranged between the first housing 4 and the second housing 6;

[0158] A binocular camera 12, wherein the binocular camera 12 is disposed on the other side of the first housing 4, and a steering engine 31 is connected to the outside of the camera module 3;

[0159] A UWB locator 9, wherein the UWB locator 9 is disposed on the top of the first housing 4;

[0160] A battery 5, wherein the battery 5 is disposed inside the first housing 4;

[0161] A battery cover 7 is disposed on the top of the first housing 4 .

[0162] The battery cover 7 is located on the top of the battery 2 , and the tag battery 2 and the positioning tag 2 are electrically connected.

[0163] Install multiple UWB locators 9 in the pipe gallery environment, one of which is directly connected to the PC to form a fixed network, in which at least one tag has a height difference of no less than 30cm and no more than 20m with other tags in the vertical direction, and the interval between tags in the horizontal direction should be no less than 20cm and no more than 8m; the pulse eddy current probe 1 is equipped with a UWB locator 9 to receive the positioning information sent by other UWB locators 9 in real time; the UWB locator 9 sends a signal, and when the signal is transmitted to the UWB locator 9 installed on the pulse eddy current probe 1, the UWB locator 9 installed on the pulse eddy current probe 1 sends the signal back to the remaining UWB locators 9; the specific position of the pulse eddy current probe 1 is calculated based on the time difference between the sending and receiving of the signal and the flight speed of the signal; the position information and inclination attitude of the probe are received through the PC, and the data is filtered and optimized for real-time tracking and analysis. After the pipeline defect is found, the location of the defect is determined based on the recorded position data, probe attitude and retained image data;

[0164] The first housing 4 and the second housing 6 are connected from both sides by four sets of M3x4 bolts and M3 nuts, and the pulsed eddy current probe 1 in the middle is fixed by a M2x4 fastening screw passing through the second housing 6;

[0165] The binocular camera 12 is externally connected to a steering gear 31 as a steering mechanism and a texture light, wherein the UWB locator 9 is fixed by a fastening screw passing through the first housing 4, and is connected to the positioning tag battery 5 by a teyp-c to USB cable for power supply;

[0166] The direction of the pulse emitted by the pulse eddy current probe 1 is consistent with the viewing angle of the binocular camera 12, and opposite to the direction of the UWB locator 9 antenna. The direction of the pulse emitted by the pulse eddy current probe 1 is not blocked by the casing, and the casing hole near one end of the UWB locator 9 antenna is used to connect the power supply line of the pulse eddy current probe 1.

[0167] Second embodiment

[0168] Depend on Fig.21 As shown, the present invention also provides a method and device for obtaining the non-contact detection position and posture of a pulsed eddy current probe, the device comprising:

[0169] The device for obtaining the non-contact detection position and posture of a pulsed eddy current probe comprises: a first housing 4 for protecting the pulsed eddy current probe 1;

[0170] A second housing 6 for protecting the pulsed eddy current probe 1 is arranged opposite to the first housing 4, and the second housing 6 is arranged on one side of the first housing 4;

[0171] A pulsed eddy current probe 1, wherein the pulsed eddy current probe 1 is arranged between the first housing 4 and the second housing 6;

[0172] A laser radar 11, which is a type of optical locator 3 and is disposed on the other side of the first housing 4;

[0173] A narrow pulse ultrasonic locator 10, the ultrasonic device performs positioning by emitting narrow pulses, and is a type of the narrow pulse locator 2, and the narrow pulse ultrasonic locator 10 is arranged on the top of the first housing 4;

[0174] A battery 5, wherein the battery 5 is disposed inside the first housing 4;

[0175] A battery cover 7 is disposed on the top of the first housing 4 .

[0176] The battery cover 7 is located on the top of the tag battery 2 , and the battery 2 is electrically connected to the narrow pulse ultrasonic locator 10 .

[0177] Install multiple narrow pulse ultrasonic locators 10 in the pipe gallery environment. The narrow pulse ultrasonic locators 10 are directly connected to the PC to form a fixed network, in which at least one narrow pulse ultrasonic locator 10 has a height difference of not less than 30cm and not more than 20m with other narrow pulse ultrasonic locators 10 in the vertical direction, and the interval between the narrow pulse ultrasonic locators 10 in the horizontal direction should be not less than 20cm and not more than 8m. ; A narrow pulse ultrasonic locator 10 is equipped on the pulse eddy current probe 1 to receive the positioning information sent by other narrow pulse ultrasonic locators 10 in real time; The positioning base station sends a signal, and when the signal is transmitted to the narrow pulse ultrasonic locator 10 on the pulse eddy current probe 1, the narrow pulse ultrasonic locator 10 on the pulse eddy current probe 1 sends the signal back to other narrow pulse ultrasonic locators 10; Based on the time difference between the sending and receiving of the signal and the flight speed of the signal, the specific position of the pulse eddy current probe 1 is calculated; The position information and inclination attitude of the probe are received through the PC, and the data is filtered and optimized for real-time tracking and analysis. After the pipeline defect is found, the location of the defect is determined based on the recorded position data, probe attitude and retained image data;

[0178] The first housing 4 and the second housing 6 are connected from both sides by four sets of M3x4 bolts and M3 nuts, and the pulsed eddy current probe 1 in the middle is fixed by a M2x4 fastening screw passing through the second housing 6;

[0179] The narrow pulse ultrasonic locator 10 is fixed by a fastening screw passing through the first housing 4 and is connected to the battery 5 by a teyp-c to USB cable for power supply;

[0180] The pulse transmitting direction of the pulse eddy current probe 1 is consistent with the scanning direction of the laser radar 11, and is opposite to the direction of the antenna of the narrow pulse ultrasonic locator 10. The pulse transmitting direction of the pulse eddy current probe 1 is not blocked by the casing, and the casing hole near one end of the antenna of the positioning tag 2 is used to connect the power supply line of the pulse eddy current probe 1.

[0181] Compared with the related art, the method and device for obtaining the non-contact detection position and posture of the pulsed eddy current probe provided by the present invention have the following beneficial effects:

[0182] It can not only obtain the position and posture of the pulsed eddy current probe 1 relative to the inspected component, but also obtain the spatial orientation of the inspected area, which is not only conducive to the correction of the test results, improving the detection accuracy and the detection rate of local defects such as pits and cracks, but also conducive to judging whether the current test results are valid and marking the position of the test results, thereby providing accurate guidance for subsequent processing.

[0183] See also Figure 2 , Figure 3 and Figure 5 Based on the device for obtaining the non-contact detection position and posture of the pulsed eddy current probe provided in the first embodiment of the present application, the second embodiment of the present application proposes another device for obtaining the non-contact detection position and posture of the pulsed eddy current probe. The second embodiment is only a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the independent implementation of the first embodiment.

[0184] Specifically, the difference between the device for obtaining the non-contact detection position and posture of the pulse eddy current probe provided in the second embodiment of the present application is that the device for obtaining the non-contact detection position and posture of the pulse eddy current probe adopts a narrow pulse ultrasonic locator 11 for basic positioning, and uses a laser radar 11 to correct the position coordinates. A threaded ring 8 is fixedly installed inside the battery cover 7, and an abutment column 81 is threadedly connected to the inner side surface of the threaded ring 8. A pressure plate 84 is provided at the bottom of the abutment column 81, and a rubber pad 85 is fixedly installed at the bottom of the pressure plate 84.

[0185] A groove 82 is defined at the top of the abutting post 81 .

[0186] The bottom of the abutting column 81 is rotatably connected to a connecting column 83 , and the bottom of the connecting column 83 is fixedly mounted on the top of the pressing plate 84 .

[0187] The first shell 4 has a cavity for installing the battery 5. When installing the battery 5, the battery 5 is placed into the cavity, and then the battery cover 7 is inserted into the first shell 4. Then, the bottom of the abutment column 81 is screwed into the cavity. At this time, the outer side of the abutment column 81 will contact the inner side of the cavity, which can limit the battery cover 7. When the bottom of the rubber pad 85 abuts against the top of the battery 5, it can also limit the battery 5.

[0188] The top of the connecting column 83 is rotatably connected to the bottom of the abutting column 81. In this way, when the bottom of the rubber pad 85 contacts the top of the label battery 5, when the abutting column 81 rotates, it will not drive the rubber pad 85 to rotate and rub on the top of the battery 5, thereby protecting the battery 5.

[0189] The working principle of the device for obtaining the non-contact detection position and posture of the pulsed eddy current probe provided by the present invention is as follows:

[0190] When in use, the battery cover 7 is inserted into the top of the first shell 4, and then the finger is placed on the inner side of the groove 82, and then the abutment column 81 is rotated to make the abutment column 81 threadedly connected with the inner side of the thread ring 8, and then the bottom of the abutment column 81 drives the pressure plate 84 and the rubber pad 85 to move downward, so that the bottom of the rubber pad 85 abuts against the top of the battery 5.

[0191] Compared with the related art, the device for obtaining the non-contact detection position and posture of the pulsed eddy current probe provided by the present invention has the following beneficial effects:

[0192] By rotating the abutment column 81, the abutment column 81 is threadedly connected to the inner side of the thread ring 8, so that the bottom of the abutment column 81 drives the pressure plate 84 and the rubber pad 85 to abut the top of the battery 5. This can not only limit the battery 5, but also limit the battery cover 7, thereby increasing the stability of the installation.

[0193] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for obtaining a pulsed eddy current probe non-contact detection position and posture, characterized in that: include: S1. Deploy narrow pulse locators to establish a coordinate system of the object to be measured, and obtain the initial coordinates and posture of the pulsed eddy current probe according to the spatial position relationship between each narrow pulse locator; S2. Process the data obtained by the optical locator through a visual algorithm to calculate the correction value of the relative spatial position between the probe and the object to be measured; electrically connect the narrow pulse locator installed on the object to be measured to the battery and the PC end, and electrically connect the optical locator to the PC end to achieve the effect of returning the obtained initial value coordinates, posture, and correction value to the PC end; S3.

1. A narrow pulse positioning medium is sent between the narrow pulse locator on the measured object and each of the narrow pulse locators, and the distance between each narrow pulse locator is calculated using the speed of the pulse and the time required for a round trip to obtain the initial coordinates; S3.2, the optical positioner calculates the correction value according to the algorithm, and the correction value includes the offset distance of the pulsed eddy current probe relative to the object to be measured in the vertical direction and the horizontal direction; S3.3, the narrow pulse locator integrates a posture detection module, calculates the posture, and returns the posture and the initial coordinates to the PC end; S4, after returning the initial coordinate data to the PC end, filtering the first several groups of the initial coordinate data to obtain filtered data; S5. Based on the filtered data, add the correction value to the horizontal and vertical coordinate values ​​to obtain the integrated coordinates; S6, respectively calculating the variance and mean of the integrated coordinates and the filtered coordinates, integrating the two data to calculate the weight k of the two, and obtaining the final coordinates, so as to reduce the impact of the obstacle blocking the signal; When there is a significant deviation in the weight, a warning will be displayed on the PC.

2. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 1 is characterized in that: S1 includes: The number of the narrow pulse locators is ≥ 5, and the height difference between at least one of the narrow pulse locators and the other narrow pulse locators in the vertical direction is [0.30m, 20.00m], and the interval between the labels in the horizontal direction is [0.20m, 8.00m]. One narrow pulse locator is provided on the pulse eddy current probe; one narrow pulse locator is provided above the object to be measured.

3. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 1 is characterized in that: The filtering of the acquired initial coordinate data in S4 includes: The initial coordinate data is returned to the PC, and the previous groups of initial coordinate data are integrated into a linear relationship to predict the next group of initial coordinate data. The weights are then solved based on the variance relationship between the predicted values ​​and the actual values ​​to obtain the filtered data.

4. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 3 is characterized in that: In S5, the correction value is combined with the filtered data to obtain the integrated coordinates: Based on the filtered data, the correction value is added to the horizontal and vertical coordinate values ​​to obtain the integrated coordinates.

5. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 4, characterized in that: In S6, the weighting of the integrated coordinates and the filtered coordinates is calculated, and the final coordinates are obtained after integration, which includes: The variance and mean of the integrated coordinates and the filtered coordinates are calculated respectively, and the two data are integrated to calculate the weight k of the two, so as to obtain the final coordinates, so as to reduce the influence of the obstacle blocking the signal; When calculating k, if k>0.85 or k<0.15, we will mark the coordinate status at this time as unreliable, display an early warning on the PC, and the staff will check the working status and working temperature of the equipment.

6. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 1, characterized in that: The specific steps of obtaining the filtered data in S4 are: S4.

1. The signal returned by the narrow pulse locator to the PC can be listed as The form of A is the mean of the returned signal, σ A is the variance, is the predicted value relationship for the next second, where μ B is the mean of the predicted values, σ B is the variance of the predicted value. X B , X A Putting it all together, we list the formula where kX A is the weight, (1-k) is X B The weight, is the required signal value after calculation to eliminate the burr; S4.

2. Integrate it into in is the variance of the whole formula. When the variance is minimum, the weight k is calculated. Derivation yields The relationship can be expressed as S4.

3. The mean of the integration into The variance is integrated into At this time we order We can Therefore, we receive the mean signal μ at this moment A , we can quickly predict the next signal μ B , and then calculate the weights of these two values ​​according to the relationship between their variances, and finally obtain the filtered data 7. The method for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 1, characterized in that: The specific steps of S6 are: S6.

1. List the corrected coordinates as The filtered data is where μ A μ B is the coordinate signal mean, σ A σ B is the variance of the two sets of data; S6.

2. Integrate the two sets of data into Where k is the weight of correcting the coordinate data, The final coordinates obtained after calculation are written as S6.

3. Calculate the final coordinate value when the variance is minimum, and construct the function from the variance formula Derivation yields It can be written as Simplify the mean into The variance is simplified to This time Available The data is processed and the final coordinates are obtained. When performing S6, if k>0.85 or k<0.15, we will mark the coordinate status at this time as unreliable and display an early warning on the PC. At the same time, the staff should check each narrow pulse locator and optical locator.

8. A device for obtaining the position and posture of a pulsed eddy current probe for non-contact detection, characterized in that: include: A first housing for protecting the pulsed eddy current probe; A second housing for protecting the pulsed eddy current probe, which is arranged opposite to the first housing, and the second housing is arranged on one side of the first housing; A pulsed eddy current probe, wherein the pulsed eddy current probe is arranged between the first shell and the second shell; An optical positioner, the optical positioner is arranged on the other side of the first housing, and a steering gear is arranged inside the optical positioner; A narrow pulse locator, the narrow pulse locator being arranged on the top of the first housing; A battery, wherein the battery is disposed inside the first housing; A battery cover is arranged on the top of the first housing.

9. The device for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 8, characterized in that: The battery cover is located on the top of the tag battery, and the battery is electrically connected to the narrow pulse locator.

10. The device for obtaining the non-contact detection position and posture of a pulsed eddy current probe according to claim 9, characterized in that: A threaded ring is fixedly installed inside the battery cover, and an abutment column is threadedly connected to the inner side surface of the threaded ring. A pressure plate is provided at the bottom of the abutment column, a rubber pad is fixedly installed at the bottom of the pressure plate, and a groove is provided at the top of the abutment column; a connecting column is rotatably connected to the bottom of the abutment column, and the bottom of the connecting column is fixedly installed on the top of the pressure plate.

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