Blind hole inner surface defect detection method and system based on OCT imaging

Abstract

The present invention belongs to the field of defect detection technology. A method and system for detecting inner surface defects of blind holes based on OCT imaging are provided, so that the OCT probe entering vertically along the center direction of the blind hole axis is tilted at a set rotation angle; the distance from the OCT probe to the bottom of the blind hole is determined according to the rotation angle, the depth of the entire blind hole, the diameter of the OCT probe, the depth information of the 0° scanning position when the OCT probe completes a full scan for the first time, the depth information of the 180° scanning position when the OCT probe completes a full scan for the first time, and the depth information of the 0° scanning position at the current depth; the distance range of L is scanned in the upper and lower ranges of the current position of the OCT probe, and after the scanning is completed, the OCT probe continues to move forward and locates to the next distance of L to continue scanning until all scans are completed, and the scanned images are spliced ​​to detect the inner surface defects of the blind hole, thereby realizing the precise positioning of the OCT probe.

Description

Technical Field

[0001] The present invention relates to the technical field of defect detection, and in particular to a method and system for detecting inner surface defects of blind holes based on OCT imaging. Background Art

[0002] The statements in this section merely provide background art related to the present invention and do not necessarily constitute prior art.

[0003] Optical Coherence Tomography (OCT) is a non-contact, non-destructive imaging method with fast imaging speed, which is currently widely used in the field of ophthalmic testing. OCT imaging equipment can be used to scan the inner surface structure of the blind hole of large instruments. The specific process is generally to install the OCT probe on a robotic arm, which drives the OCT probe into the blind hole and uses the OCT probe to image the entire inner surface of the blind hole. Due to the limited scanning imaging range of the OCT probe, the OCT probe continuously rotates and scans a circle during the imaging process, and the OCT probe continuously moves. The obtained images are spliced ​​to obtain a complete image.

[0004] In the above scanning process, the axial movement of the OCT probe is completely controlled by the robot arm, so the error of its axial movement is caused by the movement accuracy of the robot arm itself. Due to cost and technical limitations, when the axial control accuracy of the robot arm is not high, it will lead to errors in the judgment of the true value of the specific position where the OCT probe enters, that is, it is impossible to know the accurate real-time detection position (that is, the distance from the OCT probe to the bottom of the blind hole).

[0005] At present, some researchers have tried to compensate for the errors caused by movement by adding hardware such as sensors to the OCT probe, but this will incur additional costs and is not applicable to blind holes with smaller inner diameters. At the same time, the existing detection schemes cannot determine the specific direction, shape and size of the tiny holes on the surface. Direct forward scanning along the original vertical path may damage the OCT probe and fail to perform the maximum scanning. In addition, due to inaccurate judgment of the scanning position, it will also cause excessive overlap or defects in image stitching, making the final synthesized scan image incomplete. Summary of the invention

[0006] In order to address the deficiencies in the prior art, the present invention provides a method and system for detecting inner surface defects of a blind hole based on OCT imaging, which overcomes the problem of defects in the spliced ​​image caused by the low precision of the robotic arm, and enables the OCT probe that enters vertically along the center direction of the blind hole axis to be tilted at a set rotation angle, determines the distance from the OCT probe to the bottom of the blind hole, and realizes precise positioning of the OCT probe, thereby achieving more comprehensive and higher-precision defect detection.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a method for detecting inner surface defects of blind holes based on OCT imaging.

[0009] A blind hole inner surface defect detection method based on OCT imaging includes the following processes:

[0010] The OCT probe entering the blind hole is tilted to a set rotation angle;

[0011] Determine the distance from the OCT probe to the bottom of the blind hole according to the rotation angle, the depth of the entire blind hole, the diameter of the OCT probe, the depth information of the 0° scanning position when the OCT probe completes the first scan, the depth information of the 180° scanning position when the OCT probe completes the first scan, and the depth information of the 0° scanning position at the current depth;

[0012] The distance range of L is scanned in the upper and lower ranges of the current position of the OCT probe. After the scan is completed, the OCT probe continues to move forward and locates to the next distance of L to continue scanning until the entire scan is completed. The scanned images are spliced ​​and then the inner surface defects of the blind hole are detected.

[0013] As a further limitation of the first aspect of the present invention, the distance from the OCT probe to the bottom of the blind hole is ,include: ,in, is the rotation angle, is the depth of the entire blind hole, is the diameter of the OCT probe, It is the depth information of the 0° scanning position when the OCT probe makes its first complete scan. It is the depth information of the 180° scanning position when the OCT probe makes its first complete scan. It is the depth information of the 0° scanning position at the current depth.

[0014] As a further limitation of the first aspect of the present invention, the rotation angle The limited scope includes: ,in, is the diameter of the blind hole.

[0015] As a further limitation of the first aspect of the present invention, the depth information of the 180° scanning position at the current depth is , when the OCT probe continues to probe into the blind hole and When it starts to decrease, stop scanning.

[0016] As a further limitation of the first aspect of the present invention, the rotation angle Acquisition, including:

[0017] Make the OCT probe located at the center of the blind hole and obtain the distance between the OCT probe and the inner wall of the blind hole. ;

[0018] The OCT probe is tilted, and the position of the tilted OCT probe is taken as the original position. A mobile scan is performed within the range of the upper and lower set distances to obtain multiple scanned images. This process is recorded as one area scan, and the scanned images are processed to obtain the scanned area corresponding to each scanned image. The average value is obtained after calculating the average value. ;

[0019] Move the OCT probe to perform multiple area scans and calculate the average area of ​​each scan. Calculate the average again to get the final area average , according to the final area mean And the distance , get the rotation angle .

[0020] As a further limitation of the first aspect of the present invention, the OCT probe is located at the axial center of the blind hole, including:

[0021] The OCT probe enters in a direction parallel to the axis of the blind hole, and scans to obtain the radial distance between the OCT probe and the inner arm of the blind hole, so that the radial distance of one scan is equal. At this time, the OCT probe is at the axis of the blind hole, and the radial distance at this time is obtained. .

[0022] As a further limitation of the first aspect of the present invention, the rotation angle ,include: ,in, is the total number of scanned images obtained in each scan, The total number of scans.

[0023] In a second aspect, the present invention provides a method for detecting inner surface defects of blind holes based on OCT imaging.

[0024] A blind hole inner surface defect detection method based on OCT imaging includes the following processes:

[0025] When only the outer edge surface of the blind hole can be observed, when the OCT probe is controlled to enter the blind hole surface, a preliminary scan is performed, and then the set rotation angle is deflected to obtain the elliptical area obtained by the two scans;

[0026] If the ellipse area increases, it is determined that the axis of the blind hole is close to the OCT probe that enters the measurement for the first time. If the ellipse area decreases, it is determined that the axis of the blind hole is close to the OCT probe after deflection, and the axis of the blind hole is determined;

[0027] After the axis of the blind hole is determined, the process of the blind hole inner surface defect detection method based on OCT imaging described in the first aspect of the present invention is performed.

[0028] In a third aspect, the present invention provides a blind hole inner surface defect detection system based on OCT imaging.

[0029] A blind hole inner surface defect detection system based on OCT imaging, comprising: a control terminal, a mechanical arm, and an OCT probe located at the end of the mechanical arm;

[0030] The control terminal is connected to the robotic arm and the OCT probe. The robotic arm is used to drive the OCT probe to move under the control of the control terminal. The control terminal is used to perform detection control according to the blind hole inner surface defect detection method based on OCT imaging described in the first aspect of the present invention.

[0031] In a fourth aspect, the present invention provides a blind hole inner surface defect detection system based on OCT imaging.

[0032] A blind hole inner surface defect detection system based on OCT imaging, comprising: a control terminal, a deflection angle displacement slide, a rotation angle displacement slide and an OCT probe, wherein the control terminal is connected to the deflection angle displacement slide, the rotation angle displacement slide and the OCT probe respectively;

[0033] The deflection angle displacement slide is used to control the deflection angle of the OCT probe under the control of the control terminal, and the rotation angle displacement slide is used to control the rotation angle of the OCT probe under the control of the control terminal. The control terminal is used to perform detection control according to the blind hole inner surface defect detection method based on OCT imaging described in the first aspect of the present invention.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention innovatively proposes a blind hole inner surface defect detection method based on OCT imaging, which overcomes the problem of defects in the spliced ​​image caused by the low precision of the robotic arm. The OCT probe entering the blind hole is tilted at a set rotation angle, and the distance from the OCT probe to the bottom of the blind hole is determined, thereby achieving precise positioning of the OCT probe, thereby achieving more comprehensive and higher-precision defect detection.

[0036] 2. The present invention innovatively proposes a rotation angle determination strategy, taking the position of the tilted OCT probe as the original position, performing mobile scanning within the range of the upper and lower set distances to obtain multiple scanned images, calculating the scan area corresponding to each scanned image, and averaging to obtain the area mean of an area scan. , move the OCT probe to perform multiple area scans, and calculate the average area of ​​each scan. The mean And the distance between the OCT probe and the inner wall of the blind hole when it is located at the axis of the blind hole and not rotated , get the rotation angle , achieving precise measurement of rotation accuracy, thereby improving the positioning accuracy of the OCT probe.

[0037] 3. When only the outer edge surface of the blind hole can be observed, when the OCT probe is controlled to enter the blind hole surface, a preliminary scan is performed, and then the set rotation angle is deflected to obtain the elliptical area obtained by the two scans; if the elliptical area becomes larger, it is determined that the axis of the blind hole is close to the OCT probe that entered the measurement for the first time; if the elliptical area decreases, it is determined that the axis of the blind hole is close to the deflected OCT probe, which improves the scope of application of the present invention, can effectively realize the judgment of the internal direction and shape of the blind hole, and thus avoid the collision of the OCT probe.

[0038] 4. The present invention sets the rotation angle The limited range avoids damage to the OCT probe. When the OCT probe continues to probe into the blind hole and When it starts to decrease, stop scanning to further protect the OCT probe.

[0039] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0041] Figure 1 A cross-sectional view of the OCT probe provided by the present invention obliquely entering a blind hole;

[0042] Figure 2 A schematic diagram of the cooperation between the robotic arm and the OCT probe provided by the present invention;

[0043] Figure 3 A schematic diagram of the cooperation between the slide table and the OCT probe provided by the present invention;

[0044] Figure 4A schematic diagram of detecting a tapered hole provided by the present invention;

[0045] Figure 5 A schematic diagram of detecting an inverted tapered hole provided by the present invention;

[0046] Among them, 1. OCT probe; 2. Robotic arm; 3. Swing angle displacement slide; 4. Rotation angle displacement slide. DETAILED DESCRIPTION

[0047] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0048] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0049] At present, the resolution of OCT can reach 1μm. Using an endoscopic OCT imaging system to detect related blind holes or tiny through holes can greatly accurately detect defects on the inner surface of the hole. In addition, the three-dimensional imaging characteristics of OCT itself, that is, during the scanning and imaging process, it carries depth information, which can directly present the defects on the inner surface of the hole. Compared with traditional detection methods, its size information for defects, including protrusions, pits and even scratches, can be accurate to the micron level, and its position accuracy can also reach the millimeter level. In this implementation, the high-precision characteristics of the OCT imaging system itself are used to directly process the radial position information obtained by scanning relative to the OCT imaging system, so as to obtain real-time scanning axial position information.

[0050] Specifically, this implementation provides a blind hole inner surface defect detection method based on OCT imaging, including the following process:

[0051] like Figure 1 As shown, the OCT probe 1 perpendicular to the surface of the blind hole and entering along the center direction of the blind hole axis is tilted by a certain rotation angle. , start scanning imaging, first rotate and scan around the central axis of OCT probe 1 and slowly translate toward the bottom of the blind hole until the depth information is obtained after scanning one circle, that is, the tilt rotation angle After that, the lowest end of the OCT probe 1 scans touches the edge of the hole.

[0052] Since the OCT probe 1 is tilted at a certain rotation angle The trajectory of one scan is an ellipse. The three-dimensional image is sectioned to obtain a two-dimensional image. Here, one rotation is to obtain the corresponding depth information to the side wall of the blind hole. At this time, the rotation speed is r / s, where is the diameter of the blind hole, and the depth information of the 0° and 180° scanning positions is obtained, that is, and , here the robot arm 2 is used to drive the OCT probe 1, such as Figure 2 The robot arm 2 drives the OCT probe 1 to advance a certain distance along the axial direction of the blind hole, and then performs a corresponding rotation scan around the central axis to obtain the depth information after a rotation scan again. and , which is the depth information obtained from OCT scanning;

[0053] Combined rotation angle , the depth of the entire blind hole , Depth from OCT probe 1 to the opening of the blind hole and the diameter of the OCT probe 1 , where h and H are measured by measuring tools, and the diameter of the OCT probe 1 is known information, the real-time position information detected can be obtained, that is, the distance from the OCT probe 1 to the bottom of the blind hole , without adding any other hardware, only relying on OCT's high-precision imaging scanning technology, to obtain , we need to know the distance from the extended line of the hole edge to the OCT probe 1 , can be obtained from formula (1):

[0054] (1);

[0055] Real-time depth information of OCT probe 1 for:

[0056] (2);

[0057] Get real-time depth information After that, scan the upper and lower ranges of this position respectively The distance range, and then continue to locate forward to the next The scan is repeated at a distance of 100 mm / s. Each scanned image is guaranteed to have overlapping parts and there will be no missed scans, so that the final scanned and stitched image can be complete.

[0058] In order to ensure that the OCT probe 1 does not touch the side wall of the blind hole during scanning and thus damage the OCT probe 1, in this implementation, the diameter of the hole needs to be measured. ,ensure , at the same time, when When it starts to decrease, the scanning needs to be stopped, so as to ensure that the OCT probe 1 is not damaged.

[0059] In this implementation, preferably, a rotation angle is proposed The measurement method includes the following process:

[0060] The OCT probe 1 enters in a direction parallel to the axis of the blind hole, and can scan and obtain the radial distance between the OCT probe 1 and the inner wall of the blind hole. As the OCT probe 1 continues to enter and according to the radial position information of the scan, the radial distance of one scan is adjusted to be equal. At this time, the OCT probe 1 is at the axial center of the blind hole. As the OCT probe 1 moves forward, when the average value of the distance between the surface of the blind hole scanned by the OCT probe 1 and the OCT probe 1 is equal, the OCT probe 1 moves along the center of the axis and obtains the distance at this time. (i.e., the distance from the inner wall of the blind hole), and then tilt the OCT probe 1 to scan. and are equal, then the OCT probe 1 is at the axial center of the blind hole.

[0061] To ensure that the OCT probe 1 is deflected with the OCT probe 1 as the origin, Figure 3 As shown, a yaw angle displacement slide 3 is added to the system to realize hardware control, and then the position of the OCT probe 1 is determined in combination with the above-mentioned positioning method. The position of the origin remains unchanged. During the rotation control process, the position where the OCT probe 1 emits light is ensured to be the center of the circle of the OCT probe 1, that is, the fixed point during the rotation process. At the same time, in order to ensure that the rotation and the angle offset do not affect each other, an electric rotation angle displacement slide 4 is selected for control, and the specific position of the OCT probe 1 is determined by the method mentioned in the present invention.

[0062] The OCT probe 1 scans one circle to obtain depth information by performing edge recognition on the image. After the OCT probe 1 is deflected, only a small range of distance of the long axis of the scanned elliptical trajectory is used to calculate the angle, which will be subject to greater noise interference, and there are defects on the inner wall of the blind hole. Therefore, the area of ​​multiple scans is used to determine the axial center of the OCT probe 1 at the blind hole after deflection.

[0063] With the position of the deflected OCT probe 1 as the original position, a mobile scan is performed within a range of 0.2 mm (i.e., the set distance) to obtain multiple scanned images. This process is recorded as one area scan, and the scanned image is processed to obtain the scanned area. And average according to formula (3):

[0064] (3);

[0065] in, , is the total number of images obtained in each scan, Representative Scan.

[0066] Move the OCT probe 1 to perform multiple area scans. When the average area obtained each time differs by Below this level, the OCT probe 1 is always moved in the center of the axis, and the average value of multiple area measurements is taken:

[0067] (4);

[0068] in, is the total number of scans.

[0069] According to area To calculate the angle :

[0070] (5).

[0071] In order to solve the problem that only the outer edge of the blind hole can be seen, and in the process of measurement, since the size of the hole is very small and no sensor can be added, when the OCT probe 1 is controlled to enter the blind hole surface, a preliminary rotation scan is performed, and then it is deflected by a certain angle. The above method and formula are combined to measure the change in the area of ​​the two ellipses. If the area of ​​the ellipse increases, it proves that the axis of the hole is close to the OCT probe 1 that entered the measurement for the first time. If the area of ​​the ellipse decreases, it proves that the axis of the hole is close to the OCT probe 1 after deflection. At this time, the deflection angle The value of is determined, and the only deflection direction is also determined. Compared with the case of only scanning imaging, the specific position of the defect after imaging can be directly obtained, rather than being limited to judging whether there is a defect. Specifically, after determining the internal direction of the blind hole, according to the above-mentioned detection scanning method, the entry direction of the probe is adjusted to achieve complete detection of the unknown hole.

[0072] In combination with the method provided above in the present implementation, internal imaging detection of blind holes can be realized. For example, detection of tiny through holes with a diameter less than 1 mm can be realized. The OCT probe 1 used for medical endoscopy can be selected for detection, which satisfies the defect detection in tiny spaces. It can be understood that as long as an accurate image of the inside of the blind hole after splicing is obtained, some existing recognition algorithms can be used for defect recognition. The defect recognition algorithm can be implemented in an existing manner, which will not be described in detail here.

[0073] In view of the blind hole inner surface defect detection method based on OCT imaging provided above, the present implementation also proposes a blind hole inner surface defect detection system based on OCT imaging, including: a control terminal, a mechanical arm 2, and an OCT probe 1 located at the end of the mechanical arm 2;

[0074] The control terminal is connected to the robotic arm 2 and the OCT probe 1. The robotic arm 2 is used to drive the OCT probe 1 to move under the control of the control terminal. The control terminal is used to perform detection control according to the above-mentioned blind hole inner surface defect detection method based on OCT imaging.

[0075] A blind hole inner surface defect detection system based on OCT imaging can also be provided, comprising: a control terminal, a yaw angle displacement slide, a rotation angle displacement slide and an OCT probe 1, wherein the control terminal is respectively connected to the yaw angle displacement slide, the rotation angle displacement slide and the OCT probe 1; the yaw angle displacement slide is used to control the deflection angle of the OCT probe 1 under the control of the control terminal, the rotation angle displacement slide is used to control the rotation angle of the OCT probe 1 under the control of the control terminal, and the control terminal is used to perform detection control according to the above-mentioned blind hole inner surface defect detection method based on OCT imaging of the present invention.

[0076] More specifically, this implementation provides the following experimental cases:

[0077] Case 1:

[0078] In this case, during the blind hole inspection process on large instruments, first, for holes with equal cross-sectional diameters, an OCT probe 1 with an axial resolution of 1 μm was used to adjust the deflection angle The angle of deflection is 30°, the diameter of the blind hole is 10mm, and the depth is 9mm, so the deflection angle can ensure the safety of the OCT probe 1. When the moving distance is 2mm, the error of the six-axis robot 2 directly driving the OCT probe 1 forward is 0.2mm according to the theoretical value of the robot 2. When the OCT probe 1 is tilted 30°, the axial moving distance of the OCT probe 1 in the blind hole is 1mm. Combined with the scanning resolution of the OCT probe 1 of 1μm, the maximum error of this distance is mm, this error fully meets the error requirements in the imaging stitching process. It can ensure the integrity of the imaging. Compared with direct vertical entry, its absolute error is .

[0079] Case 2:

[0080] like Figure 4 As shown, during the detection of tapered holes, it is necessary to know the bottom angle If the robot 2 is used to directly drive the OCT probe 1 with an axial resolution of 2μm to move 1mm, the error is 0.1mm, so the deflection angle is 45°, When the moving distance of OCT probe 1 along the center of the blind hole axis is 1 mm, the moving distance of OCT probe 1 is 2 mm. In this case, the moving distance along the center of the blind hole axis is calculated as follows: , and The depth information obtained by the two scans is respectively. For the scanning of the conical hole, the distance information scanned by the side of the OCT probe 1 should be used as the calculated distance. The error is related to the resolution of the OCT. Therefore, the error between the actual moving distance and the actual position obtained by the method of the present invention is mm.

[0081] Case 3:

[0082] During the inspection of the flipped tapered hole, , where if the robot arm 2 is used to directly drive the OCT probe 1 with an axial resolution of 1.5μm to move 3mm, the error is 0.2mm, and the deflection angle is 50°. When the moving distance of the OCT probe 1 in the center direction of the blind hole axis is 3mm, the moving distance of the OCT probe 1 is mm, for the scanning of the conical hole, the distance information scanned by the side of the OCT probe 1 should be used as the calculated distance, and the error is related to the resolution of the OCT and the number of significant digits retained for rational numbers. Compared with the error caused by the resolution, the error caused by the number of significant digits retained is negligible. Therefore, the error between the actual moving distance and the actual position obtained by the method of the present invention is mm.

[0083] In summary, the present invention utilizes the high resolution characteristic of the OCT imaging technology itself to achieve the real position positioning of the OCT probe 1 and can meet the accuracy required by the industry.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A blind hole inner surface defect detection method based on OCT imaging, characterized in that: The process includes: The OCT probe entering the blind hole is tilted to a set rotation angle; Rotation Angle Acquisition, including: Make the OCT probe located at the center of the blind hole and obtain the distance between the OCT probe and the inner wall of the blind hole. ; The OCT probe is tilted, and the position of the tilted OCT probe is taken as the original position. A mobile scan is performed within the range of the upper and lower set distances to obtain multiple scanned images. This process is recorded as one area scan, and the scanned images are processed to obtain the scanned area corresponding to each scanned image. The average value is obtained after calculating the average value. ; Move the OCT probe to perform multiple area scans and calculate the average area of ​​each scan. Calculate the average again to get the final area average , according to the final area mean And the distance , get the rotation angle ; The rotation angle ,include: ,in, is the total number of scanned images obtained in each scan, is the total number of scans; Determine the distance from the OCT probe to the bottom of the blind hole according to the rotation angle, the depth of the entire blind hole, the diameter of the OCT probe, the depth information of the 0° scanning position when the OCT probe completes the first scan, the depth information of the 180° scanning position when the OCT probe completes the first scan, and the depth information of the 0° scanning position at the current depth; The distance range of L is scanned in the upper and lower ranges of the current position of the OCT probe. After the scan is completed, the OCT probe continues to move forward and locates to the next distance of L to continue scanning until the entire scan is completed. The scanned images are spliced ​​and then the inner surface defects of the blind hole are detected.

2. The blind hole inner surface defect detection method based on OCT imaging according to claim 1, characterized in that: Distance from OCT probe to bottom of blind hole ,include: ,in, is the rotation angle, is the depth of the entire blind hole, is the diameter of the OCT probe, It is the depth information of the 0° scanning position when the OCT probe makes its first complete scan. It is the depth information of the 180° scanning position when the OCT probe makes its first complete scan. It is the depth information of the 0° scanning position at the current depth.

3. The blind hole inner surface defect detection method based on OCT imaging according to claim 2, characterized in that: Rotation Angle The limited scope includes: ,in, is the diameter of the blind hole.

4. The method for detecting inner surface defects of blind holes based on OCT imaging according to claim 1 or 2, characterized in that: The depth information of the 180° scanning position at the current depth is , when the OCT probe continues to probe into the blind hole and When it starts to decrease, stop scanning.

5. The blind hole inner surface defect detection method based on OCT imaging according to claim 1, characterized in that: The OCT probe is centered on the axis of the blind hole, including: The OCT probe enters in a direction parallel to the axis of the blind hole, and scans to obtain the radial distance between the OCT probe and the inner wall of the blind hole, so that the radial distance of one scan is equal. At this time, the OCT probe is at the axis of the blind hole, and the radial distance at this time is obtained. .

6. A blind hole inner surface defect detection method based on OCT imaging, characterized in that: The process includes: When only the outer edge surface of the blind hole can be observed, when the OCT probe is controlled to enter the blind hole surface, a preliminary scan is performed, and then the set rotation angle is deflected to obtain the elliptical area obtained by the two scans; If the ellipse area increases, it is determined that the axis of the blind hole is close to the OCT probe that enters the measurement for the first time. If the ellipse area decreases, it is determined that the axis of the blind hole is close to the OCT probe after deflection, and the axis of the blind hole is determined; After determining the axis of the blind hole, the process of the blind hole inner surface defect detection method based on OCT imaging as described in claim 1 or 2 is performed.

7. A blind hole inner surface defect detection system based on OCT imaging, characterized in that: include: Control terminal, robotic arm and OCT probe located at the end of the robotic arm; The control terminal is connected to the robotic arm and the OCT probe. The robotic arm is used to drive the OCT probe to move under the control of the control terminal. The control terminal is used to perform detection control according to the blind hole inner surface defect detection method based on OCT imaging according to claim 1 or 2.

8. A blind hole inner surface defect detection system based on OCT imaging, characterized in that: include: A control terminal, a yaw angle displacement slide, a rotation angle displacement slide, and an OCT probe, wherein the control terminal is connected to the yaw angle displacement slide, the rotation angle displacement slide, and the OCT probe respectively; The deflection angle displacement slide is used to control the deflection angle of the OCT probe under the control of the control terminal, and the rotation angle displacement slide is used to control the rotation angle of the OCT probe under the control of the control terminal. The control terminal is used to perform detection control according to the blind hole inner surface defect detection method based on OCT imaging according to claim 1 or 2.

Images