TOFD probe attitude adjusting system and method

Abstract

The invention belongs to the technical field of nondestructive testing, and discloses a TOFD probe attitude adjusting system and method.The TOFD probe attitude adjusting system comprises a first rotating motor and a controller which are fixedly installed; an output shaft of the first rotating motor is fixedly connected with a first connecting piece, and a second rotating motor is fixedly mounted on the first connecting piece; the central axis of the output shaft of the first rotating motor and the central axis of the output shaft of the second rotating motor intersect at one point, and the intersection point is defined as a fixed intersection point; an output shaft of the second rotating motor is fixedly connected with a second connecting piece, the second connecting piece is used for being connected with a TOFD probe unit, and the TOFD probe unit comprises a force measuring part used for monitoring the contact force between the TOFD probe unit and a measured object in real time; an acoustic beam incidence point of the TOFD probe unit coincides with the fixed intersection point; the problems that in the prior art, due to the fact that it is difficult to keep the position of a probe sound beam incidence point stable while two-dimensional posture adjustment is achieved, harmful translation is generated in the posture adjusting process, and force sensing signals are disturbed are effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of nondestructive testing technology, specifically relating to a TOFD probe attitude adjustment system and method. Background Technology

[0002] In time-of-flight ultrasonic diffraction (TOFD) testing, precise control of the probe attitude is crucial for ensuring the quality of the detection signal. Currently, commonly used attitude adjustment methods fall into two main categories: manual adjustment relying on operator experience, and auxiliary adjustment using passive compliant structures such as springs and floating supports. Manual adjustment is inefficient and inconsistent, while passive compliant structures, although providing some adaptability, are essentially passive deformations with fixed stiffness, unable to actively and dynamically adjust their attitude based on real-time changes in the contact force between the probe and the workpiece. Both methods struggle to maintain stable coupling at the probe's acoustic beam incident point when dealing with complex curved surfaces or workpieces with uneven surface conditions, easily leading to uneven probe pressure and poor coupling agent distribution, thus affecting detection accuracy.

[0003] To improve automation, existing technologies have attempted to use multi-axis motion mechanisms to actively control probe attitude. However, when achieving two-dimensional probe attitude adjustment (i.e., simultaneously possessing pitch and roll degrees of freedom), such general-purpose mechanisms face an inherent structural limitation: to provide two rotational degrees of freedom, their mechanical configuration makes it difficult for the probe's rotation center (or instantaneous rotation center) to always coincide with its actual detection point (sound beam incident point). In common solutions (such as serial articulated robots, cross slides combined with rotary tables, etc.), the position of the probe's sound beam incident point relative to the mechanism's drive axis changes during movement, causing unnecessary collateral displacement (i.e., harmful translation) of the incident point on the workpiece surface when adjusting the angle. This translation not only directly interferes with the established ultrasonic coupling layer but also introduces additional sliding friction unrelated to attitude changes at the probe-workpiece contact surface, severely contaminating the measurement signal of the contact force sensor. Therefore, existing technologies suffer from the problem of harmful translation and interference with force sensing signals during attitude adjustment due to the difficulty in maintaining the probe's sound beam incident point position stable while achieving two-dimensional attitude adjustment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a TOFD probe attitude adjustment system and method, which solves the problem in existing technologies that it is difficult to maintain the stable position of the probe's acoustic beam incident point while achieving two-dimensional attitude adjustment, thus causing harmful translation and interference with the force sensing signal during the attitude adjustment process.

[0005] The objective of this invention can be achieved through the following technical solutions: A TOFD probe attitude adjustment system includes a fixedly mounted first rotating motor and a controller; The output shaft of the first rotary motor is fixedly connected to the first connector, and the second rotary motor is fixedly mounted on the first connector. The central axis of the output shaft of the first rotary motor intersects the central axis of the output shaft of the second rotary motor at a single point, which is defined as a fixed intersection point. The output shaft of the second rotating motor is fixedly connected to a second connector. The second connector is used to connect the TOFD probe unit. The TOFD probe unit includes a force measuring part for real-time monitoring of the contact force between the TOFD probe unit and the object being measured. The incident point of the sound beam in the TOFD probe unit coincides with the fixed intersection point; The controller's signal input terminal is communicatively connected to the signal output terminal of the TOFD probe unit to receive contact force signals; The controller's control output is connected to the first and second rotating motors for communication purposes, so as to control the first and second rotating motors to work together and drive the TOFD probe unit to adjust its attitude around a fixed intersection point.

[0006] Furthermore, the TOFD probe unit also includes a wedge, on which the probe body for emitting ultrasonic waves is fixedly mounted. The wedge is made of an elastic material and can undergo elastic deformation when subjected to external force. The wedge has an internally hollowed-out frame structure. Inside the wedge are a first crossbeam and a second crossbeam that are perpendicular to each other, and the plane containing the axis of the first crossbeam is parallel to the plane containing the second crossbeam. The force measuring unit includes a first FBG sensor and a second FBG sensor; The first FBG sensor is installed on the first crossbeam and is used to measure the component of the contact force along the axial direction of the first crossbeam. The second FBG sensor is installed on the second crossbeam and is used to measure the component of the contact force along the axial direction of the second crossbeam.

[0007] Furthermore, a third FBG sensor is also installed on the wedge to monitor the ambient temperature and perform temperature compensation for the measurement and calculation of the contact force.

[0008] Furthermore, the number of both the first crossbeam and the second crossbeam is set to multiple, and the total number of the first FBG sensor and the second FBG sensor is less than or equal to the total number of the first crossbeam and the second crossbeam.

[0009] A method for adjusting the attitude of a TOFD probe, using the aforementioned TOFD probe attitude adjustment system to perform TOFD probe attitude adjustment, includes the following steps: Real-time acquisition of the contact force between the TOFD probe unit and the object being measured; With the contact force being less than or equal to a preset threshold as the control target, the target attitude angle adjustment amount that the TOFD probe unit needs to adjust around a fixed intersection point is calculated. Based on the spatial geometric relationship of the sound beam incident points of the first rotating motor, the second rotating motor, and the TOFD probe unit, the mapping relationship between the target attitude angle adjustment amount and the target rotation angles corresponding to the first rotating motor and the second rotating motor is determined, and the target attitude angle adjustment amount is calculated into the target rotation angles of the first rotating motor and the second rotating motor respectively. The controller controls the first and second rotating motors to rotate to the corresponding target angles to adjust the attitude of the TOFD probe unit.

[0010] Furthermore, the contact force between the TOFD probe unit and the object under test is acquired in real time, specifically including the following steps: The wavelength changes corresponding to the monitoring process of the first FBG sensor and the second FBG sensor are obtained respectively, and used as the corresponding strain data. Using the wavelength change of the third FBG sensor as temperature reference data, the strain data corresponding to the first FBG sensor and the second FBG sensor are compensated to obtain the compensated strain data. Based on the mapping relationship between strain and force, the components of the contact force along the axial direction of the first beam and the components of the contact force along the axial direction of the second beam are calculated.

[0011] Furthermore, taking a contact force less than or equal to a preset threshold as the control target, the target attitude angle adjustment amount that the TOFD probe unit needs to adjust around a fixed intersection point is calculated. The specific calculation formula is as follows: In the formula, e Indicates a preset threshold; This represents the component of the contact force along the axial direction of the first crossbeam; This represents the component of the contact force along the axial direction of the second crossbeam; This indicates the target attitude angle adjustment amount in the axial direction of the first crossbeam; This indicates the target attitude angle adjustment amount in the axial direction of the second crossbeam; Indicates proportional gain; This represents the integral gain.

[0012] Furthermore, based on the spatial geometric relationship of the sound beam incident points of the first rotary motor, the second rotary motor, and the TOFD probe unit, the mapping relationship between the target attitude angle adjustment and the target rotation angle corresponding to the first rotary motor and the second rotary motor is determined, specifically including the following steps: Establish the first coordinate system with the sound beam incident point of the TOFD probe unit as the first origin. ,in, The axis is vertically upward. The shaft extends axially along the first crossbeam. The shaft extends axially along the second crossbeam; A second coordinate system is established with the intersection of the rotation axis of the second rotary motor's output shaft and the end face of its output end as the second origin. The second coordinate system is derived from the first coordinate system around... First angle of axis rotation Then, it is translated to coincide with the second origin to obtain the result, and The shaft coincides with the center axis of the output shaft of the second rotary motor; A third coordinate system is established with the intersection of the rotation axis of the first rotating motor's output shaft and the end face of its output end as the third origin. The third coordinate system is derived from the second coordinate system around... Second angle of axis rotation Then, it is translated to coincide with the third origin to obtain the result, and The shaft coincides with the central axis of the output shaft of the first rotating motor. Based on the first angle Second angle The rotation transformation matrices from the first coordinate system to the second and third coordinate systems are calculated respectively, and the mapping relationship between the target attitude angle adjustment and the target rotation angles corresponding to the first and second rotating motors is derived.

[0013] Furthermore, from the first angle 45°, the second angle It is 65°; The rotation transformation matrix between the first coordinate system and the second coordinate system is: The specific mathematical expression is as follows: The rotation transformation matrix between the first coordinate system and the third coordinate system is: The specific mathematical expression is as follows: in, This represents the rotation transformation matrix between the second and third coordinate systems.

[0014] Based on the rotation transformation matrix, the mapping model between the target attitude angle adjustment and the target rotation angle is constructed as follows: Further derivation and transformation yield the following mapping relationship: In the formula, Indicates the target rotation angle of the first rotating motor; This indicates the target rotation angle of the second rotating motor.

[0015] The beneficial effects of this invention are: 1. This invention constructs a dedicated actuator with kinematic decoupling by configuring the output shaft center axes of the first and second rotary motors to intersect at a fixed intersection point and coincide with the sound beam incident point of the TOFD probe unit. This enables the TOFD probe unit to achieve precise two-dimensional attitude adjustment around the fixed intersection point, eliminating the harmful probe translation caused by motion coupling during traditional attitude adjustment from a mechanical perspective. Simultaneously, the integrated force-sensing TOFD probe unit forms a closed loop with the controller, which can actively and dynamically coordinate the rotation of the first and second rotary motors based on real-time contact force signals. This invention achieves adaptive active contact of the TOFD probe unit with workpiece surfaces of different curvatures, fundamentally solving the technical bottlenecks of uneven probe pressure, unstable coupling, and poor surface following, significantly improving the coupling quality, signal consistency, and automated detection capability for complex surfaces in TOFD detection. 2. This invention provides a TOFD probe attitude adjustment method. Through a closed-loop process of real-time acquisition of contact force signals, calculation of the desired attitude angle with a preset threshold as the target, and mapping the attitude angle to the target rotation angle of dual motors according to a fixed geometric relationship, the method achieves full automation and precision from force sensing to attitude execution. This method transforms the traditional attitude adjustment process that relies on manual experience into an intelligent control process based on a physical model. It not only completely overcomes the defects of low efficiency and poor consistency of manual attitude adjustment, as well as the inability of passive flexible attitude adjustment to actively adapt to curved surfaces, but also ensures that the probe can maintain a stable and optimal contact state on various workpiece surfaces through force compliance control. This significantly improves the coupling reliability, signal quality, and adaptive detection capability of TOFD detection on complex surfaces. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the first coordinate system, the second coordinate system, and the third coordinate system of the present invention; Figure 3 This is a schematic diagram of the TOFD probe unit structure of the present invention; Figure 4 This is a schematic diagram of the side wall structure of the wedge block of the present invention, which is parallel to the second crossbeam; Figure 5 This is a schematic diagram of the side wall structure of the wedge block of the present invention, which is parallel to the first crossbeam. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figures 1 to 5 As shown, a TOFD probe attitude adjustment system includes a first rotating motor 100 and a controller that are fixedly installed. The output shaft of the first rotary motor 100 is fixedly connected to the first connector 200, and the second rotary motor 300 is fixedly mounted on the first connector 200. The central axis of the output shaft of the first rotary motor 100 intersects the central axis of the output shaft of the second rotary motor 300 at a point, which is defined as a fixed intersection point; The output shaft of the second rotary motor 300 is fixedly connected to a second connector 400. The second connector 400 is used to connect to the TOFD probe unit 500. The TOFD probe unit 500 includes a force measuring part for real-time monitoring of the contact force between the TOFD probe unit 500 and the object being measured. The sound beam incident point of the TOFD probe unit 500 coincides with the fixed intersection point; The controller’s signal input terminal is communicatively connected to the signal output terminal of the TOFD probe unit 500 to receive contact force signals. The controller's control output terminal is connected to the first rotating motor 100 and the second rotating motor 300 respectively to control the first rotating motor 100 and the second rotating motor 300 to work together and drive the TOFD probe unit 500 to adjust its attitude around a fixed intersection point; This invention constructs a dedicated actuator with kinematic decoupling by configuring the output shaft center axes of the first rotary motor 100 and the second rotary motor 300 to intersect at a fixed intersection point and coincide with the sound beam incident point of the TOFD probe unit 500. This enables the TOFD probe unit 500 to achieve precise two-dimensional attitude adjustment around the fixed intersection point, eliminating the harmful probe translation caused by motion coupling during traditional attitude adjustment from a mechanical perspective. Simultaneously, the TOFD probe unit 500, which integrates force sensing, forms a closed loop with the controller. The controller can actively and dynamically coordinate the rotation of the first rotary motor 100 and the second rotary motor 300 based on real-time contact force signals. This invention achieves adaptive active contact of the TOFD probe unit 500 with workpiece surfaces of different curvatures, fundamentally solving the technical bottlenecks of uneven probe pressure, unstable coupling, and poor surface following, significantly improving the coupling quality, signal consistency, and automated detection capability for complex surfaces in TOFD detection. Meanwhile, the intersecting axis dual-electric mechanism adopted in this invention integrates two rotational degrees of freedom in a compact space behind the probe. Unlike traditional two-axis turntables, it does not require the rotation axis and the probe's acoustic beam incident point to be on the same height plane. This significantly reduces the radial dimension and structural complexity of the probe's execution end, making the system more suitable and flexible in integration in confined spaces or restricted detection environments.

[0020] Preferably, the housing of the first rotary motor 100 is provided with a first threaded hole so as to install and fix the first rotary motor 100 to an external device; Preferably, the second connector 400 is detachably connected to the TOFD probe unit 500 by bolts.

[0021] The TOFD probe unit 500 also includes a wedge 501, on which a probe body 502 for emitting ultrasonic waves is fixedly mounted. The wedge 501 is made of an elastic material and can undergo elastic deformation when subjected to external force. The wedge 501 has an internally hollowed-out frame structure. Inside the wedge 501, there is a first crossbeam 503 and a second crossbeam 504 that are perpendicular to each other, and the plane containing the axis of the first crossbeam 503 is parallel to the plane containing the second crossbeam 504. The force measuring unit includes a first FBG sensor 505 and a second FBG sensor 506; The first FBG sensor 505 is arranged on the first crossbeam 503 and is used to measure the component of the contact force along the axial direction of the first crossbeam 503. The second FBG sensor 506 is arranged on the second crossbeam 504 and is used to measure the component of the contact force along the axial direction of the second crossbeam 504. Preferably, both the first crossbeam 503 and the second crossbeam 504 are provided with mounting grooves, and the first FBG sensor 505 and the second FBG sensor 506 are glued to the mounting grooves by means of adhesive. In this embodiment, the installation position of the wedge block 501 and the second FBG sensor 506 on the second crossbeam 504 is as follows: Figure 4 As shown, the grid region endpoint of the second FBG sensor 506 is located on the second crossbeam 504. b 1 and b 2 Point; The wedge 501 and the first FBG sensor 505 are mounted on the first crossbeam 503 in the following positions: Figure 5 As shown, the grid region endpoint of the first FBG sensor 505 is located on the first crossbeam 503. a 1 and a 2 Point; The wedge block 501 is provided with a liquid injection hole 508, which is used to inject coupling agent to improve the flaw detection efficiency.

[0022] The wedge 501 is also equipped with a third FBG sensor 507, which is used to monitor the ambient temperature and perform temperature compensation for the measurement and calculation of the contact force. By using the third FBG sensor 507 to monitor the ambient temperature in real time, the drift error caused by temperature changes to the contact force signals measured by the first FBG sensor 505 and the second FBG sensor 506 is effectively eliminated, thereby significantly improving the accuracy and long-term stability of two-dimensional contact force measurement and ensuring the accuracy and reliability of the force feedback-based attitude control system.

[0023] The number of first crossbeams 503 and second crossbeams 504 is set to multiple, and the total number of first FBG sensors 505 and second FBG sensors 506 is less than or equal to the total number of first crossbeams 503 and second crossbeams 504. Preferably, the first crossbeam 503 and the second crossbeam 504 within the wedge 501 can be configured as multi-layer stacked structures. This design, while maintaining the mechanical decoupling characteristics of the orthogonal crossbeams, significantly improves the space utilization of the structure, realizes high sensitivity sensing of two-dimensional contact forces within the limited volume of the wedge 501, and makes the entire force sensing probe unit structure more compact and robust, facilitating integration into the TOFD probe attitude adjustment system.

[0024] A method for adjusting the attitude of a TOFD probe, using the aforementioned TOFD probe attitude adjustment system to perform TOFD probe attitude adjustment, includes the following steps: Real-time acquisition of the contact force between the TOFD probe unit 500 and the object being measured; With the contact force being less than or equal to a preset threshold as the control target, calculate the target attitude angle adjustment amount that the TOFD probe unit 500 needs to adjust around a fixed intersection point. Based on the spatial geometric relationship of the sound beam incident points of the first rotating motor 100, the second rotating motor 300 and the TOFD probe unit 500, the mapping relationship between the target attitude angle adjustment amount and the target rotation angles corresponding to the first rotating motor 100 and the second rotating motor 300 is determined, and the target attitude angle adjustment amount is calculated into the target rotation angles of the first rotating motor 100 and the second rotating motor 300 respectively. The controller controls the first rotating motor 100 and the second rotating motor 300 to rotate to the corresponding target angle, so as to adjust the attitude of the TOFD probe unit 500; By acquiring contact force signals in real time, calculating the desired attitude angle with a preset threshold as the target, and mapping the attitude angle to the target rotation angle of the dual motors according to a fixed geometric relationship, a closed-loop process is achieved, realizing full automation and precision from force sensing to attitude execution. This method transforms the traditional attitude adjustment process that relies on human experience into an intelligent control process based on a physical model. It not only completely overcomes the defects of low efficiency and poor consistency of manual attitude adjustment, as well as the inability of passive flexible attitude adjustment to actively adapt to curved surfaces, but also ensures that the probe can maintain a stable and optimal contact state on various workpiece surfaces through force compliance control. This significantly improves the coupling reliability, signal quality, and adaptive detection capability of TOFD detection on complex surfaces.

[0025] Real-time acquisition of the contact force between the TOFD probe unit 500 and the object under test includes the following steps: The wavelength changes corresponding to the monitoring process of the first FBG sensor 505 and the second FBG sensor 506 are obtained respectively. Using the wavelength change of the third FBG sensor 507 as temperature reference data, the corresponding wavelength changes of the first FBG sensor 505 and the second FBG sensor 506 are compensated to obtain the compensated wavelength change. Based on the mapping relationship between wavelength change and force, the components of the contact force along the axial direction of the first crossbeam 503 and the components of the contact force along the axial direction of the second crossbeam 504 are calculated respectively. Preferably, when there are multiple first FBG sensors 505 or second FBG sensors 506, the average wavelength change of the multiple first FBG sensors 505 or second FBG sensors 506 is taken as the strain data.

[0026] With the contact force being less than or equal to a preset threshold as the control target, the target attitude angle adjustment amount that the TOFD probe unit 500 needs to adjust around a fixed intersection point is calculated. The specific calculation formula is as follows: In the formula, e represents the preset threshold; This represents the component of the contact force along the axial direction of the first crossbeam 503; This represents the component of the contact force along the axial direction of the second crossbeam 504; This indicates the target attitude angle adjustment amount in the axial direction of the first crossbeam 503; This indicates the target attitude angle adjustment amount in the axial direction of the second crossbeam 504; Indicates proportional gain; This represents the integral gain.

[0027] Based on the spatial geometric relationship of the sound beam incident points of the first rotating motor 100, the second rotating motor 300, and the TOFD probe unit 500, the mapping relationship between the target attitude angle adjustment amount and the target rotation angles corresponding to the first rotating motor 100 and the second rotating motor 300 is determined, specifically including the following steps: A first coordinate system is established with the sound beam incident point of the TOFD probe unit 500 as the first origin. ,in, The axis is vertically upward. The shaft extends axially along the first crossbeam 503. The shaft extends axially along the second crossbeam 504; A second coordinate system is established with the intersection of the rotation axis of the output shaft of the second rotary motor 300 and the end face of its output end as the second origin. The second coordinate system is derived from the first coordinate system around... First angle of axis rotation Then, it is translated to coincide with the second origin to obtain the result, and The shaft coincides with the center axis of the output shaft of the second rotary motor 300; A third coordinate system is established with the intersection of the rotation axis of the output shaft of the first rotary motor 100 and the end face of its output end as the third origin. The third coordinate system is derived from the second coordinate system around... Second angle of axis rotation Then, it is translated to coincide with the third origin to obtain the result, and The shaft coincides with the central axis of the output shaft of the first rotating motor 100; Based on the first angle Second angle The rotation transformation matrices from the first coordinate system to the second and third coordinate systems are calculated respectively, and the mapping relationship between the target attitude angle adjustment and the target rotation angles corresponding to the first rotating motor 100 and the second rotating motor 300 is derived.

[0028] First angle 45°, the second angle It is 65°; The rotation transformation matrix between the first coordinate system and the second coordinate system is: The specific mathematical expression is as follows: The rotation transformation matrix between the first coordinate system and the third coordinate system is: The specific mathematical expression is as follows: in, This represents the rotation transformation matrix between the second and third coordinate systems.

[0029] Based on the rotation transformation matrix, the mapping model between the target attitude angle adjustment and the target rotation angle is constructed as follows: The following derivation and transformation are performed: The following mapping relationship is obtained by simplification: In the formula, This indicates the target rotation angle of the first rotating motor 100; This indicates the target rotation angle of the second rotating motor 300.

[0030] The mathematical expression for the mapping relationship between wavelength change and applied force is as follows: In the formula, dS Indicates the amount of wavelength change; Indicates the initial feedback wavelength; y This indicates the distance from the first FBG sensor 505 or the second FBG sensor 506 to the neutral surface of the corresponding first crossbeam 503 or second crossbeam 504; The strain is the strain at the point furthest from the neutral plane on the first beam 503 or the second beam 504. R This indicates half the thickness of the first crossbeam 503 or the second crossbeam 504; I The moment of inertia represents the cross-section of the instrument's axis. ; indicates the width of the first crossbeam 503 or the second crossbeam 504. w 2 is a preset value; Wavelength change of the third FBG sensor 507 dS 0 is only related to ambient temperature. dS 0 and temperature change dT Between ,in, The coefficient of thermal expansion is The thermo-optic coefficient is denoted as .

[0031] make F= 0.2 N and will F Substituting into the above formula, we can calculate... dS ;like dS >10pm, then it can be considered F When the wavelength difference of the FBG sensor is 0.2N, it can be detected by the fiber optic demodulator, meaning the force-sensing TOFD probe has sufficiently high force resolution. Therefore, the length of the corresponding first beam 503 or second beam 504 at this time... s 1 and thickness s 2 These are desirable design parameters; The wavelength changes of the first FBG sensor 505, the second FBG sensor 506, and the third FBG sensor 507 can be recorded using a fiber optic demodulator; among them, the wavelength change of the third FBG sensor 507... dS 0 should be used as the temperature reference data (temperature drift), and the corresponding wavelength changes of the first FBG sensor 505 and the second FBG sensor 506 should be subtracted from it. dS 0, to obtain the wavelength change after compensation.

[0032] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A TOFD probe attitude adjustment system, comprising a fixedly mounted first rotating motor (100) and a controller, characterized in that: The output shaft of the first rotary motor (100) is fixedly connected to the first connector (200), and the second rotary motor (300) is fixedly mounted on the first connector (200). The central axis of the output shaft of the first rotary motor (100) intersects the central axis of the output shaft of the second rotary motor (300) at a point, and the intersection point is defined as a fixed intersection point; The output shaft of the second rotary motor (300) is fixedly connected to a second connector (400). The second connector (400) is used to connect the TOFD probe unit (500). The TOFD probe unit (500) includes a force measuring part for real-time monitoring of the contact force between the TOFD probe unit (500) and the object being measured. The sound beam incident point of the TOFD probe unit (500) coincides with the fixed intersection point; The signal input terminal of the controller is communicatively connected to the signal output terminal of the TOFD probe unit (500) to receive contact force signals; The controller's control output terminal is connected to the first rotating motor (100) and the second rotating motor (300) respectively to control the first rotating motor (100) and the second rotating motor (300) to work together and drive the TOFD probe unit (500) to adjust its attitude around a fixed intersection point.

2. The TOFD probe attitude adjustment system according to claim 1, characterized in that, The TOFD probe unit (500) also includes a wedge (501), on which a probe body (502) for emitting ultrasonic waves is fixedly mounted. The wedge (501) is made of elastic material and can undergo elastic deformation when subjected to external force. The wedge (501) has an internally hollowed-out frame structure. Inside the wedge (501) are a first crossbeam (503) and a second crossbeam (504) that are perpendicular to each other. The plane containing the axis of the first crossbeam (503) is parallel to the plane containing the second crossbeam (504). The force measuring unit includes a first FBG sensor (505) and a second FBG sensor (506); The first FBG sensor (505) is arranged on the first crossbeam (503) and is used to measure the component of the contact force along the axial direction of the first crossbeam (503). The second FBG sensor (506) is arranged on the second crossbeam (504) and is used to measure the component of the contact force along the axial direction of the second crossbeam (504).

3. The TOFD probe attitude adjustment system according to claim 2, characterized in that, A third FBG sensor (507) is also provided on the wedge (501) to monitor the ambient temperature for temperature compensation in the measurement calculation of the contact force.

4. The TOFD probe attitude adjustment system according to claim 3, characterized in that, The number of the first crossbeam (503) and the second crossbeam (504) is set to multiple, and the total number of the first FBG sensor (505) and the second FBG sensor (506) is less than or equal to the total number of the first crossbeam (503) and the second crossbeam (504).

5. A method for adjusting the attitude of a TOFD probe, comprising using the TOFD probe attitude adjustment system as described in claim 3 or 4 to perform TOFD probe attitude adjustment, characterized in that, Includes the following steps: Real-time acquisition of the contact force between the TOFD probe unit (500) and the object being measured; With the contact force being less than or equal to a preset threshold as the control target, the target attitude angle adjustment amount that the TOFD probe unit (500) needs to be adjusted around a fixed intersection point is calculated; Based on the spatial geometric relationship of the sound beam incident points of the first rotating motor (100), the second rotating motor (300) and the TOFD probe unit (500), the mapping relationship between the target attitude angle adjustment amount and the target rotation angles corresponding to the first rotating motor (100) and the second rotating motor (300) is determined, and the target attitude angle adjustment amount is calculated as the target rotation angles of the first rotating motor (100) and the second rotating motor (300) respectively. The controller controls the first rotating motor (100) and the second rotating motor (300) to rotate to the corresponding target angle, so as to adjust the attitude of the TOFD probe unit (500).

6. The TOFD probe attitude adjustment method according to claim 5, characterized in that, Real-time acquisition of the contact force between the TOFD probe unit (500) and the object under test includes the following steps: The wavelength changes corresponding to the monitoring process of the first FBG sensor (505) and the second FBG sensor (506) are obtained respectively; Using the wavelength change of the third FBG sensor (507) as temperature reference data, the corresponding wavelength changes of the first FBG sensor (505) and the second FBG sensor (506) are compensated to obtain the compensated wavelength change. Based on the mapping relationship between wavelength change and force, the components of the contact force along the axial direction of the first crossbeam (503) and the components of the contact force along the axial direction of the second crossbeam (504) are calculated respectively.

7. The TOFD probe attitude adjustment method according to claim 6, characterized in that, With the contact force being less than or equal to a preset threshold as the control target, the target attitude angle adjustment amount that the TOFD probe unit (500) needs to be adjusted around a fixed intersection point is calculated. The specific calculation formula is as follows: In the formula, e Indicates a preset threshold; This represents the component of the contact force along the axial direction of the first crossbeam (503); This represents the component of the contact force along the axial direction of the second crossbeam (504); This indicates the target attitude angle adjustment amount in the axial direction of the first crossbeam (503); This indicates the target attitude angle adjustment amount in the axial direction of the second crossbeam (504); Indicates proportional gain; This represents the integral gain.

8. The TOFD probe attitude adjustment method according to claim 7, characterized in that, Based on the spatial geometric relationship of the sound beam incident points of the first rotating motor (100), the second rotating motor (300), and the TOFD probe unit (500), the mapping relationship between the target attitude angle adjustment amount and the target rotation angle corresponding to the first rotating motor (100) and the second rotating motor (300) is determined, specifically including the following steps: A first coordinate system is established with the sound beam incident point of the TOFD probe unit (500) as the first origin. ,in, The axis is vertically upward. The shaft extends axially along the first crossbeam (503). The shaft extends axially along the second crossbeam (504); A second coordinate system is established with the intersection of the rotation axis of the output shaft of the second rotary motor (300) and the end face of its output end as the second origin. The second coordinate system is derived from the first coordinate system around... First angle of axis rotation Then, it is translated to coincide with the second origin to obtain the result, and The shaft coincides with the center axis of the output shaft of the second rotary motor (300); A third coordinate system is established with the intersection of the rotation axis of the output shaft of the first rotating motor (100) and the end face of its output end as the third origin. The third coordinate system is derived from the second coordinate system around... Second angle of axis rotation Then, it is translated to coincide with the third origin to obtain the result, and The shaft coincides with the central axis of the output shaft of the first rotating motor (100); Based on the first angle Second angle The rotation transformation matrices from the first coordinate system to the second and third coordinate systems are calculated respectively, and the mapping relationship between the target attitude angle adjustment and the target rotation angle corresponding to the first rotating motor (100) and the second rotating motor (300) is derived.

9. The TOFD probe attitude adjustment method according to claim 8, characterized in that, First angle 45°, the second angle It is 65°; The rotation transformation matrix between the first coordinate system and the second coordinate system is: The specific mathematical expression is as follows: The rotation transformation matrix between the first coordinate system and the third coordinate system is: The specific mathematical expression is as follows: in, This represents the rotation transformation matrix between the second and third coordinate systems. Based on the rotation transformation matrix, the mapping model between the target attitude angle adjustment and the target rotation angle is constructed as follows: Further derivation and transformation yield the following mapping relationship: In the formula, This indicates the target rotation angle of the first rotating motor (100); This indicates the target rotation angle of the second rotating motor (300).

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