An optical projection system and method for ultrasonic testing of defect locations

Abstract

This invention belongs to the field of ultrasonic testing technology, specifically a defect location optical projection system and method for ultrasonic testing. The system includes an ultrasonic testing instrument, an ultrasonic probe, a data processing unit, and an optical projection device. The ultrasonic testing instrument and ultrasonic probe perform conventional ultrasonic testing functions, detecting defects and calculating their horizontal distance L. The data processing unit receives the horizontal distance L and, based on pre-input or stored probe parameters, calculates accurate projection coordinates using a mapping algorithm. The optical projection device receives instructions from the data processing unit and emits visible laser light. In this invention, the system uses the data processing unit to accurately convert the abstract defect horizontal distance data output by the ultrasonic testing instrument into projected coordinates on the workpiece surface, combined with probe parameters. The optical projection device then projects visible marks in real time, eliminating the need for manual marking and making the defect location intuitively visible. This significantly improves positioning accuracy by eliminating the need for secondary estimation by operators.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic testing technology, and in particular to an optical projection system and method for defect location in ultrasonic testing. Background Technology

[0002] In traditional ultrasonic testing technology, the ultrasonic testing instrument usually relies on generating high-frequency electrical pulses to excite the ultrasonic probe. The ultrasonic probe performs electro-acoustic and acoustic-electric conversion, transmits sound waves to the workpiece and receives the defect echo signal. After receiving and amplifying the echo signal, the ultrasonic testing instrument calculates the depth and horizontal distance of the defect.

[0003] However, the defect coordinate data (such as horizontal distance) obtained at this time is only abstract data from within the instrument. During transverse wave ultrasonic testing, when a defect is detected, the instrument can display data such as the depth and horizontal position of the defect. Operation requires holding the probe still with one hand and using a ruler to measure the horizontal position with the other to determine if the defect is on the weld. This is not a problem for a single person operating on a platform, but it becomes very problematic when operating alone at heights or in confined spaces. Therefore, corresponding improvements have been made to address this issue. Summary of the Invention

[0004] Based on the technical problems existing in the prior art, this invention proposes an optical projection system and method for defect location in ultrasonic testing.

[0005] The present invention proposes an optical projection system for defect location in ultrasonic testing, comprising an ultrasonic testing instrument, an ultrasonic probe, a data processing unit, and an optical projection device; The ultrasonic testing instrument and ultrasonic probe are responsible for performing routine ultrasonic testing functions, detecting defects and calculating their horizontal distance L; The data processing unit receives the horizontal distance L and, based on pre-input or stored probe parameters (such as probe leading edge L0 and K value), calculates the accurate projection coordinates using a mapping algorithm. The core algorithm is S = Kd - L0, where S is the actual distance from the ultrasonic probe incident point along the weld direction to the defect projection point. For curved workpieces, a surface compensation algorithm can be introduced to correct S. The optical projection device (preferably a laser module) receives instructions from the data processing unit and emits visible laser light to form a clear spot at the calculated coordinate position (S), thereby transforming the abstract "digital L" into a specific "physical mark" on the workpiece.

[0006] Preferably, the probe parameters include at least the probe leading edge distance L0 and the probe K value, and the data processing unit calculates the projection coordinates S through the mapping algorithm S=Kd-L0, where S is the actual distance from the probe incident point to the projected light spot.

[0007] Preferably, the optical projection device is a laser module, and its light emission direction and the direction of the main ultrasonic beam maintain a fixed geometric relationship in the longitudinal plane of the probe; the laser beam should be parallel to the axis of the main ultrasonic beam, so that no matter how far the ultrasonic probe is from the surface of the workpiece (within a reasonable range), the laser spot can indicate the position of the beam axis on the surface of the workpiece. Combined with the above algorithm, defects can be accurately marked.

[0008] Preferably, the laser module and the ultrasonic probe are integrated into a single structure, and the optical projection axis and ultrasonic beam axis have been calibrated before leaving the factory. The laser module is permanently encapsulated in the housing of the ultrasonic probe, and the housing is specially designed to provide an installation position and light emission port for the laser module. When using the device, the user only needs to connect the ultrasonic probe to an ultrasonic testing instrument compatible with this invention, and the instrument can automatically identify the probe parameters to achieve "plug and play" without any on-site calibration, ensuring the highest reliability and ease of operation.

[0009] Preferably, the laser module is a universal accessory independent of the ultrasonic probe, fixed to the probe by a detachable clamping mechanism, and includes a calibration module for on-site calibration; it includes its own housing, laser module, data processing unit, power supply and clamping mechanism, which can be spring clip, magnetic base, strap or clamp, etc., so that it can be firmly attached to various existing probes; the calibration module can be a physical button, which is used in conjunction with a specific operating procedure.

[0010] Preferably, when the inspected workpiece is a curved surface, the data processing unit is also configured with a surface compensation algorithm, which corrects the projected coordinates S based on the workpiece's radius of curvature. This algorithm requires the user to input the workpiece's radius of curvature R. After calculating the straight-line distance S, the data processing unit will calculate the central angle corresponding to the arc length S according to geometric principles, and then calculate the angle that the laser beam needs to deflect in order to project to the end point of the arc length, or directly calculate the projection correction amount in the tangential direction.

[0011] Preferably, the data processing unit is integrated inside the ultrasonic detector, inside the optical projection device, or in a separate external controller.

[0012] Preferably, the optical projection device is capable of responding to multiple defect signals by simultaneously or sequentially projecting multiple defect locations using light spots of different colors, flashing frequencies, or shapes. Simultaneous projection: If the laser module can be composed of multiple laser diodes (such as red, green, and blue lasers), different colored light spots can be projected simultaneously to distinguish defects of different natures (e.g., red indicates an out-of-range defect, green indicates a recorded defect). Sequential projection / scanning: The monochromatic laser module is controlled to rapidly switch between different defect coordinates at a very high frequency. Due to the persistence of vision, the operator will see multiple light spots existing simultaneously. Alternatively, they can be distinguished by different flashing frequencies (e.g., defect 1 flashes quickly, defect 2 flashes slowly).

[0013] Preferably, the optical projection system for defect location in ultrasonic testing further includes an ambient light sensor for detecting ambient light intensity. The data processing unit dynamically adjusts the output power of the optical projection device based on the ambient light intensity. The sensor detects the ambient light intensity in real time and sends the signal to the data processing unit. The data processing unit has a pre-stored light intensity-power correspondence table or algorithm. When working in bright outdoor conditions, the laser drive current is automatically increased to make the light spot clearly visible; when working in dim environments, the power is automatically reduced, saving electricity and avoiding discomfort or potential risks to the operator's eyes from strong laser light.

[0014] In addition, the present invention also provides a defect location optical projection method for a defect location optical projection system for ultrasonic testing, comprising the following steps: S1: Enter the probe parameters of the currently used ultrasound probe; S2: Detect internal defects in the workpiece using an ultrasonic testing instrument and obtain the horizontal distance L of the defect; S3: The data processing unit calculates the projection coordinates of the optical projection device on the workpiece surface based on the probe parameters and the horizontal distance L; S4: Control the optical projection device to project the light spot representing the defect location onto the workpiece surface according to the projection coordinates.

[0015] Compared with the prior art, the present invention provides an optical projection system and method for defect location in ultrasonic testing, which has the following advantages: Improved accuracy and intuitiveness of defect location: The system uses a data processing unit to accurately convert the abstract horizontal distance data of defects output by the ultrasonic testing instrument into projected coordinates on the workpiece surface, combined with probe parameters. Then, a visible mark is projected in real time by an optical projection device. No manual marking is required, making the defect location intuitively visible and eliminating the need for secondary estimation by operators, thus greatly improving the positioning accuracy.

[0016] Enhanced ease of operation and scenario adaptability: Supports two optical projection device implementation methods: integrated probe and universal accessory. The integrated probe is calibrated and parameters are fixed before leaving the factory, achieving "plug and play" without the need for on-site calibration. The universal accessory is adapted to existing probes through a detachable clamping mechanism, and together with the on-site calibration module, it meets the reuse requirements of different probes, reduces equipment replacement costs, and adapts to diverse testing scenarios.

[0017] Solving the challenge of inspecting complex workpieces: A surface compensation algorithm is configured for curved workpieces. Combined with the workpiece curvature radius correction projection coordinates, the straight-line distance on the plane is converted into the projection position corresponding to the actual arc length on the curved surface, ensuring the accuracy of defect markings on curved workpieces and breaking through the limitations of traditional planar inspection.

[0018] Optimizing multiple defects and environmental adaptability can distinguish multiple defects by different colors, flashing frequencies, or time-sharing projection methods, making it easy to identify the location of multiple defects simultaneously; with the ambient light sensor, the data processing unit can dynamically adjust the output power of the optical projection device to ensure clear light spots in bright environments and reduce power in dim environments to avoid eye discomfort, thus balancing visibility and safety.

[0019] Lowering the barriers to equipment upgrades and use: The data processing unit can be integrated into the ultrasonic testing instrument, the optical projection device, or a separate external controller. This supports highly integrated designs for new equipment and facilitates upgrades to existing ultrasonic testing equipment without replacing the entire system. The "plug-and-play" integrated probe design also reduces the skill requirements for operators, minimizes calibration steps, and improves testing efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of an optical projection system for ultrasonic detection of defect locations proposed in this invention. Figure 2 This is a schematic diagram of coordinate transformation for an optical projection system for ultrasonic testing of defect locations proposed in this invention. Figure 3 This is a flowchart of an optical projection system for ultrasonic testing of defect locations proposed in this invention.

[0021] In the diagram: 1. Ultrasonic testing instrument; 2. Ultrasonic probe. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] Reference Figures 1-3 An optical projection system for defect location in ultrasonic testing includes an ultrasonic testing instrument 1, an ultrasonic probe 2, a data processing unit, and an optical projection device. Ultrasonic testing instrument 1: Its core functions include generating high-frequency electrical pulses to excite the probe, receiving and amplifying the echo signal, and calculating the depth d and horizontal distance L of the defect through an internal processor. In this invention, the testing instrument needs to have a data output interface (such as USB, Bluetooth, Wi-Fi, or a custom digital interface) to send out the calculated defect coordinate data (at least including the horizontal distance L).

[0025] Ultrasonic probe 2: This can be a straight probe or an angled probe. In transverse wave detection, an angled probe (such as a K-value probe) is typically used. The probe is connected to the ultrasonic testing instrument 1 via a cable to perform electro-acoustic and acoustic-electric conversion.

[0026] Data processing unit: This can be a microprocessor, microcontroller (MCU), field-programmable gate array (FPGA), or application-specific integrated circuit (ASIC). This unit receives the defect horizontal distance L from the ultrasonic testing instrument 1 and stores or receives probe parameters input by the operator. Its core function is to execute a coordinate transformation program, converting the abstract instrument data L into specific spatial coordinate instructions on the workpiece surface, and then sending this information to the optical projection device.

[0027] An optical projection device receives instructions from a data processing unit, generates a visible optical mark, and precisely projects it onto the calculated workpiece surface position. A preferred embodiment is a laser module because it can produce a high-brightness, small-spot collimated beam that is easy to observe. This module typically includes a laser diode, a driving circuit, and an optical lens. The projected beam can be steady-state or flickering to enhance attention.

[0028] In this invention, reference is made to Figure 2The probe parameters include at least the probe tip distance L0 and the probe K value. The probe tip distance L0 refers to the distance from the probe incident point (the position where the ultrasonic beam enters the workpiece) to the front end face of the probe housing. This is a fixed geometric parameter, usually calibrated at the factory. Probe K value: For angle probes, K = tanθ = L1 / d1 = L2 / d2, where θ is the transverse wave refraction angle. The data processing unit calculates the projected coordinates S using the mapping algorithm S = Kd - L0, where S is the actual distance from the probe incident point to the projected light spot.

[0029] In this invention, the optical projection device is a laser module, whose light emission direction maintains a fixed geometric relationship with the direction of the main ultrasonic beam within the longitudinal plane of the probe. Ideally, the laser beam should be parallel to the axis of the main ultrasonic beam. Thus, regardless of the distance between the ultrasonic probe 2 and the workpiece surface (within a reasonable range), the laser spot can indicate the position of the beam axis on the workpiece surface. Combined with the aforementioned algorithm, defects can be accurately marked. This fixed geometric relationship can be established and maintained in the factory through precision structural design (for integrated probes) or through on-site calibration procedures (for general-purpose accessories).

[0030] In this invention, the laser module and the ultrasonic probe 2 are integrated into a single structure, and the optical projection axis and the ultrasonic beam axis have been calibrated before leaving the factory. In this embodiment, the laser module is permanently encapsulated in the housing of the ultrasonic probe 2, and the housing is specially designed to provide the laser module with an installation position and a light output hole. "Calibration completed before leaving the factory" means that the manufacturer has adjusted the parallelism and relative position between the laser optical axis and the ultrasonic beam axis using precision instruments before leaving the factory, and has solidified the inherent L0 and K value parameters of the probe in a storage chip (such as EEPROM) inside the probe, or generated a unique probe ID associated with it. When using it, the user only needs to connect the ultrasonic probe 2 to the ultrasonic testing instrument 1 compatible with this invention, and the instrument can automatically identify the probe parameters to achieve "plug and play" without any on-site calibration, ensuring the highest reliability and ease of operation.

[0031] In this invention, the laser module is a universal accessory independent of the ultrasonic probe 2. It is fixed to the probe by a detachable clamping mechanism and includes a calibration module for on-site calibration. This embodiment is an independent, detachable module that includes its own housing, laser module, data processing unit, power supply, and clamping mechanism. The clamping mechanism can be a spring clip, magnetic base, strap, or clamp, etc., to firmly attach it to various existing probes. Due to the uncertainty of the clamping position and angle, on-site calibration is necessary. The calibration module can be a physical button, used in conjunction with a specific operating procedure. For example, the user places the probe (with the accessory clamped) at a specific position on a standard test block. When the instrument detects a reference reflector at a known position, the user manually fine-tunes the position of the accessory or inputs a command via the APP to make the laser point coincide with the actual position of the reflector. At this time, pressing the calibration button will cause the data processing unit to record the current compensation parameters (which can be regarded as an equivalent synthesis front L0').

[0032] In this invention, when the inspected workpiece is a curved surface, the data processing unit is also equipped with a curved surface compensation algorithm, which corrects the projected coordinates S based on the workpiece's radius of curvature. On a plane, the distance S is a straight line, but on a curved surface, the actual path is an arc, so a curved surface compensation algorithm is needed. The algorithm requires the user to input the workpiece curvature radius R. After calculating the straight-line distance S, the data processing unit will calculate the central angle corresponding to the arc length S according to geometric principles, and then calculate the angle that the laser beam needs to deflect in order to project to the end point of the arc length, or directly calculate the projection correction amount in the tangential direction. For example, for cylindrical workpieces, the algorithm will consider the circumferential position of the probe and convert the straight-line distance S into the corresponding arc length, thereby driving the laser module (if it supports small-angle deflection) or directly making corrections in the calculation to ensure that the spot can accurately indicate the projection position of the defect on the curved surface.

[0033] In this invention, the data processing unit is integrated inside the ultrasonic testing instrument 1, inside the optical projection device, or in a separate external controller; Integrated into the ultrasonic testing instrument 1: This is a highly integrated solution. The instrument's CPU directly executes the mapping algorithm and controls the external or built-in optical projection device through the newly added hardware interface, which helps to reduce system complexity and cost. Integrated into the optical projection device: As mentioned above, the general accessory solution has the best compatibility and can work with any conventional ultrasonic testing instrument 1 that can output L value; Independent external controller: The data processing unit can be a separate handheld device or box connected between the ultrasonic detector 1 and the optical projection device. This solution facilitates the upgrading and transformation of existing equipment.

[0034] In this invention, the optical projection device can respond to multiple defect signals and project multiple defect locations simultaneously or at different times through light spots of different colors, flashing frequencies, or shapes. In ultrasonic testing, a single scan may detect multiple defects, and the data processing unit can cache the coordinates of these defects. Simultaneous projection: If the laser module can be composed of multiple laser diodes (such as red, green and blue lasers), different colored light spots can be projected simultaneously to distinguish defects of different natures (such as red indicating defects exceeding the standard, and green indicating recording defects). Time-sharing projection / scanning: A more common implementation is to control a monochromatic laser module to switch rapidly between different defect coordinates at a very high frequency. Due to the persistence of vision, the operator will see multiple light spots existing at the same time; or, they can be distinguished by different flashing frequencies (e.g., defect 1 flashes quickly, defect 2 flashes slowly).

[0035] In this invention, the optical projection system for defect location in ultrasonic testing also includes an ambient light sensor for detecting ambient light intensity, and the data processing unit dynamically adjusts the output power of the optical projection device according to the ambient light intensity. The system incorporates an ambient light sensor (such as a photodiode or photoresistor) that detects ambient light intensity in real time and sends the signal to the data processing unit. The data processing unit pre-stores a light intensity-power correspondence table or algorithm. When working in bright outdoor conditions, the laser drive current is automatically increased to ensure a clearly visible laser spot; when working in dim environments, the power is automatically reduced, saving electricity and avoiding discomfort or potential risks to the operator's eyes from the strong laser.

[0036] In addition, the present invention also provides a defect location optical projection method for a defect location optical projection system for ultrasonic testing, comprising the following steps: S1: Input probe parameters: The operator inputs the L0 and K values ​​of the currently used probe into the system (i.e., provides them to the data processing unit) through the instrument panel, mobile APP or automatic recognition. S2: Detecting defects and obtaining the L value: The operator scans the workpiece, and when the ultrasonic detector 1 determines that there is a defect based on the echo signal, its internal algorithm will calculate the horizontal distance L of the defect in real time. S3: Calculate projection coordinates: The data processing unit is triggered, it obtains the L value, calls the stored probe parameters, and calculates the precise projection coordinates S through the core mapping algorithm (and possible surface compensation algorithm); S4: Projected light spot: The data processing unit converts the coordinate S into control commands (such as drive current, deflection angle, etc.) and sends them to the optical projection device. The optical projection device responds to the command and immediately projects a visible light spot at point S on the workpiece surface.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An optical projection system for defect location in ultrasonic testing, characterized in that, include: An ultrasonic testing instrument (1) is used to transmit and receive ultrasonic signals and to calculate the depth and horizontal distance L of the defect; An ultrasonic probe (2) is connected to the ultrasonic testing instrument (1) and is used to emit ultrasonic waves to the workpiece under inspection and receive the echo. The data processing unit is used to receive the defect horizontal distance L calculated by the ultrasonic detector (1), and convert the horizontal distance L into the projection coordinates of the optical projection device on the workpiece surface based on the preset probe parameters. An optical projection device, connected to the data processing unit, is used to project the defect location onto the workpiece surface in the form of visible light according to the projection coordinates.

2. The optical projection system for defect location in ultrasonic testing according to claim 1, characterized in that, The probe parameters include at least the probe leading edge distance L0 and the probe K value. The data processing unit calculates the projection coordinates S through the mapping algorithm S=Kd-L0, where S is the actual distance from the incident point of the ultrasonic probe (2) to the projected light spot.

3. The defect location optical projection system for ultrasonic testing according to claim 1 or 2, characterized in that, The optical projection device is a laser module, and its light output direction and the direction of the main ultrasonic beam maintain a fixed geometric relationship in the longitudinal plane of the ultrasonic probe (2).

4. The defect location optical projection system for ultrasonic testing according to claim 3, characterized in that, The laser module and the ultrasonic probe (2) are integrated into a single structure, and the optical projection axis and the ultrasonic beam axis have been calibrated before leaving the factory.

5. The defect location optical projection system for ultrasonic testing according to claim 3, characterized in that, The laser module is a general accessory independent of the ultrasonic probe (2), which is fixed to the ultrasonic probe (2) by a detachable clamping mechanism and includes a calibration module for on-site calibration.

6. The defect location optical projection system for ultrasonic testing according to claim 2, characterized in that, When the workpiece being inspected is a curved surface, the data processing unit is also equipped with a surface compensation algorithm, which corrects the projected coordinates S based on the workpiece's radius of curvature.

7. The defect location optical projection system for ultrasonic testing according to claim 1, characterized in that, The data processing unit is integrated inside the ultrasonic detector (1), inside the optical projection device, or in a separate external controller.

8. The defect location optical projection system for ultrasonic testing according to claim 1, characterized in that, The optical projection device can respond to multiple defect signals and project multiple defect locations simultaneously or at different times using light spots of different colors, flashing frequencies, or shapes.

9. The defect location optical projection system for ultrasonic testing according to claim 1, characterized in that, The optical projection system for defect location in ultrasonic testing also includes an ambient light sensor for detecting ambient light intensity, and the data processing unit dynamically adjusts the output power of the optical projection device according to the ambient light intensity.

10. A defect location optical projection method using the defect location optical projection system for ultrasonic testing as described in any one of claims 1-9, characterized in that, Includes the following steps: S1: Input the probe parameters of the currently used ultrasound probe (2); S2: The internal defects of the workpiece are detected by an ultrasonic testing instrument (1), and the horizontal distance L of the defect is obtained; S3: The data processing unit calculates the projection coordinates of the optical projection device on the workpiece surface based on the probe parameters and the horizontal distance L; S4: Control the optical projection device to project the light spot representing the defect location onto the workpiece surface according to the projection coordinates.

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