Deep hole detection device and method based on optical principle

Abstract

The invention belongs to the technical field of deep hole detection, and particularly relates to a deep hole detection device and method based on the optical principle, the device comprises a detection head and a calculation unit, the detection head comprises an annular laser generator, a rotating surface reflector and an endoscope; the endoscope is fixedly connected with the annular laser generator, and the annular laser generator and the rotating surface reflector are both coaxially arranged with the deep blind hole; the annular laser emitted by the annular laser generator is reflected by the rotating surface reflecting mirror, is converged at one point and then is divergently irradiated on the inner wall of the deep blind hole, and is used for acquiring an annular laser image on the inner wall of the deep blind hole and sending the annular laser image to the calculation unit; and the calculation unit is used for calculating point cloud coordinates of the cross section of the deep blind hole according to the annular laser image on the inner wall of the deep blind hole, and calculating geometrical characteristics of the deep blind hole according to the point cloud coordinates. According to the invention, high-precision detection can be realized, and the production quality of special-shaped deep hole parts is effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of deep hole detection technology, specifically relating to a deep hole detection device and method based on optical principles. Background Technology

[0002] With the rapid development of manufacturing and industry, more stringent precision requirements have been placed on the processing technology of hole-type components, which in turn has led to higher standards for the accuracy of inspection technologies. In particular, a portion of deep-hole components are irregularly shaped deep holes, including complex structures such as internal annular grooves and tapered holes. These irregularly shaped deep-hole structures are widely used in key components in aerospace, military equipment, and mechanical equipment. To ensure these products possess excellent performance and a long service life, the requirements for surface accuracy and geometric tolerances during the production process are extremely stringent. Therefore, accurate inspection of irregularly shaped deep holes plays a crucial role in the manufacturing process. However, current research on inspection methods for irregularly shaped deep holes is relatively limited.

[0003] In the current technological field, the inspection of irregularly shaped deep holes faces significant challenges. Both contact and non-contact inspection methods encounter major difficulties in detecting irregularly shaped deep blind holes. For contact inspection methods, the main limitation lies in the fact that traditional contact measuring tools (such as dial indicators) cannot penetrate long distances to measure when encountering variations in the hole's internal space, and they cannot effectively inspect complex geometries such as conical surfaces or the arcs of bottom holes, thus failing to meet the multi-dimensional geometric measurement requirements of irregularly shaped deep blind holes. In practical applications, companies often use custom molds inserted into the deep hole, performing qualitative inspections by observing the light-transmitting gap between the mold and the hole wall. This method has low measurement accuracy and lacks digital features. For non-contact inspection methods, due to the complexity of the hole's internal morphology, conventional non-contact measurement techniques are insufficient to meet the measurement requirements. For example, while laser rangefinders are suitable for radial measurements, their capabilities are limited when inspecting the arcs of bottom holes and small-diameter deep holes, preventing them from penetrating deep into the hole for effective measurement. In summary, both of these inspection methods have significant limitations.

[0004] Therefore, it is necessary to provide a new deep hole inspection device and method to simultaneously measure blind hole parts with different geometric features such as hole diameter, taper, and arc radius, thus providing a new solution for the inspection of irregular deep holes. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a deep hole detection device and method based on optical principles to achieve multi-geometric quantity detection of irregularly shaped deep blind holes.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a deep hole detection device based on optical principles, comprising: a detection head and a computing unit, wherein the detection head includes a ring laser generator, a rotating surface mirror, and an endoscope; The endoscope is fixedly connected to the ring laser generator, and both the ring laser generator and the rotating surface mirror are coaxially arranged with the deep blind hole. The ring laser emitted by the ring laser generator is reflected by the rotating surface mirror, converges to a point, and then diverges to irradiate the inner wall of the deep blind hole. This is used to acquire the ring laser image on the inner wall of the deep blind hole and send it to the computing unit. The computing unit is used to calculate the point cloud coordinates of the cross-section of the deep blind hole based on the ring laser image on the inner wall of the deep blind hole, and to calculate the geometric features of the deep blind hole based on the point cloud coordinates.

[0007] With the endoscope center as the origin and the deep blind hole axis as the x-axis, the formula for calculating the point cloud coordinates is as follows: x= d*tanα / (tanα-tanθ); y=d*tanα*tanθ / (tanα-tanθ); Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d represents the distance between the convergence point of the ring laser and the origin of the coordinate system; α represents half of the emission angle of the ring laser; and θ represents the field of view angle of the endoscope.

[0008] The deep hole detection device based on optical principles further includes a connecting sleeve, through which the ring laser generator is fixedly connected to the endoscope.

[0009] The rotating surface reflector is a conical surface reflector with a fixed taper, and the rotating surface reflector is fixedly connected to the ring laser generator.

[0010] The deep hole detection device based on optical principles further includes an electric slide, on which a push rod is mounted and fixedly connected to a ring laser generator; the electric slide is used to push the push rod to move, thereby causing the endoscope and the ring laser generator to move along the axis of the deep blind hole.

[0011] The rotating surface reflector is a variable taper conical surface reflector.

[0012] The deep hole detection device based on optical principles further includes a driving mechanism. The rotating surface mirror is disposed on the outer periphery of the ring laser generator and is slidably connected to the ring laser generator. The driving mechanism is used to drive the rotating surface mirror to move relative to the ring laser generator along the axis of the deep blind hole.

[0013] Furthermore, the present invention also provides a deep hole detection method based on optical principles, implemented using the aforementioned device, comprising the following steps: Step 1: Drive the endoscope and the ring laser generator to move along the axis of the deep blind hole, and acquire the ring laser image on the inner wall of the deep blind hole through the endoscope; Step 2: Calculate the point cloud coordinates of the deep blind hole cross section based on the ring laser image at each location, and unify the coordinate system according to the moving distance of the ring laser generator to obtain the final point cloud coordinates of the deep blind hole cross section at each location. Step 3: Calculate the geometric features of the deep blind hole based on the final point cloud coordinates.

[0014] Furthermore, this invention also provides another deep hole detection method based on optical principles, implemented using the aforementioned device, comprising the following steps: Step 1: Drive the rotating surface mirror to move along the axis of the deep blind hole, so that the ring laser emitted by the ring laser generator irradiates different cross-sectional positions of the deep blind hole until the ring laser irradiates the bottom of the deep blind hole; collect the ring laser image on the inner wall of the deep blind hole through the endoscope (4); Step 2: Obtain the annular laser image at each location and calculate the point cloud coordinates of the deep blind hole section; Step 3: Calculate the geometric features of the deep blind hole based on the point cloud coordinates.

[0015] The deep hole detection method based on optical principles further includes the steps of calibrating the relationship between the moving distance L of the rotating surface mirror, the distance d between the convergence point of the ring laser and the origin of the coordinate system, and half of the emission angle α of the ring laser, d(L) and α(L). In step two, based on the relationship between the moving distance L of the rotating reflector, the distance d between the convergence point of the ring laser and the origin of the coordinate system, and half of the emission angle α of the ring laser, the point cloud coordinates of the deep blind hole section are calculated from the ring laser image at each location. The calculation formula is as follows: x= d(L)*tanα(L) / (tanα(L)-tanθ); y=d(L)*tanα(L)*tanθ / (tanα(L)-tanθ); Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d(L) represents the distance between the convergence point of the ring laser and the origin of the coordinate system when the laser moves a distance L; α(L) represents half of the emission angle of the ring laser when the laser moves a distance L; and θ represents the field of view direction angle of the endoscope.

[0016] Compared with the prior art, the present invention has the following advantages: This invention proposes a deep hole inspection device and method based on optical principles. A rotating reflector reflects a ring laser output from a ring laser generator, causing it to illuminate the inner wall of a deep blind hole. An endoscope images the illumination position, enabling point cloud coordinate measurement of various cross-sections of the deep blind hole. The rotating reflector avoids positional interference between the endoscope and the ring laser generator, and also converges the ring laser, allowing it to illuminate the bottom of the deep blind hole for morphological measurement. Furthermore, by using a variable taper reflector and manipulating it to scan the ring laser at different positions on the inner wall of the deep blind hole, the travel distance is reduced, improving measurement accuracy. In summary, this invention allows for direct observation of the internal structure of deep holes, featuring a simple structure and convenient operation. It is particularly suitable for inspecting difficult-to-detect irregular deep holes with taper, arc-shaped bottoms, or variable diameter characteristics, offering a wide range of applications and achieving high-precision inspection results. Using this invention can effectively improve the production quality of irregular deep hole components and meet the demands of high-precision machining technologies. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of an optical-based detection device for irregularly shaped deep blind holes provided in Embodiment 1 of the present invention; Figure 2 This is a three-dimensional structural diagram of an optical-based irregular deep blind hole detection device provided in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram illustrating the principle of point cloud coordinate calculation in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the detection of the cylindrical segment in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the detection of the conical segment in Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the arc-shaped section at the bottom of the detection hole in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram illustrating the detection principle of an optical-based deep blind hole detection device according to Embodiment 2 of the present invention.

[0018] In the figure: 1-ring laser generator; 2-rotating surface mirror; 3-connecting sleeve; 4-industrial endoscope; 5-deep blind hole workpiece; 6-ring light ring; 8-electric precision slide; 9-long push rod; 10-locking sleeve; 11-workpiece fixing part; 12-operating table. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but 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.

[0020] Example 1 like Figure 1 As shown, Embodiment 1 of the present invention provides a deep hole detection device based on optical principles, comprising: a detection head and a calculation unit. The detection head includes a ring laser generator 1, a rotating surface reflector 2, an endoscope 4, and a calculation unit. Figure 1 As shown, the endoscope 4 is fixedly connected to the ring laser generator 1. Both the ring laser generator 1 and the rotating surface mirror 2 are coaxially arranged with the deep blind hole. The ring laser emitted by the ring laser generator 1 is reflected by the rotating surface mirror 2, converges at a point, and then diverges to irradiate the inner wall of the deep blind hole. This is used to collect the ring laser image on the inner wall of the deep blind hole and send it to the calculation unit. The calculation unit is used to calculate the point cloud coordinates of the cross-section of the deep blind hole based on the ring laser image on the inner wall of the deep blind hole, and to calculate the geometric features of the deep blind hole based on the point cloud coordinates.

[0021] like Figure 2 As shown, the deep hole detection device based on optical principle described in this embodiment also includes an operating table 12, on which a workpiece fixing part 11 is provided, and an electric slide 8 is provided on the operating table 12. The workpiece fixing part 11 is used to fix the deep blind hole workpiece 5.

[0022] Furthermore, in this embodiment of a deep hole detection device based on optical principles, the rotating surface reflector 2 is a conical surface reflector with a fixed taper, and the rotating surface reflector 2 is fixedly connected to the ring laser generator 1.

[0023] Furthermore, the deep hole detection device based on optical principles in this embodiment also includes a connecting sleeve 3, through which the ring laser generator 1 is fixedly connected to the endoscope 4.

[0024] like Figure 3 As shown, in this embodiment, a rectangular coordinate system is established with the center of endoscope 4 as the origin and the axis of the deep blind hole as the x-axis. Assuming the distance between the convergence point of the ring laser and the origin is d, the emission angle of the ring laser is 2α, the field of view angle of the endoscope is θ, and the intersection point of the ring laser and the inner wall of the deep blind hole is A, the coordinates of this intersection point A are the point cloud coordinates of the deep blind hole cross-section. The distance between intersection point A and the x-axis is R, and the distance between intersection point A and the y-axis is D. According to trigonometric relationships: R=(Dd)tanα=Dtanθ; (1) Therefore: D= d*tanα / (tanα-tanθ); (2) The formula for calculating point cloud coordinates is: x= D=d*tanα / (tanα-tanθ); (3) y=R=D tanθ=d*tanα*tanθ / (tanα-tanθ); (4) Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d represents the distance between the convergence point of the ring laser and the origin of the coordinate system; α represents half of the emission angle of the ring laser; and θ represents the field of view direction angle of the endoscope. Specifically, the field of view direction angle of the endoscope can be determined based on the coordinates of the light spot in the field of view.

[0025] In this embodiment, the above formulas (3) and (4) give Figure 2 The point cloud coordinates shown in the cross section can also be calculated using the above formula for point clouds within the cross section corresponding to different polar coordinate angles. Then, by combining the polar coordinate angles corresponding to each point cloud coordinate, the three-dimensional coordinates of the point cloud can be obtained.

[0026] Furthermore, the deep hole detection device based on optical principles in this embodiment also includes an electric slide 8, on which a push rod 9 is provided. The push rod 9 is fixedly connected to the ring laser generator 1 through a locking sleeve 10. The electric slide 8 is used to push the push rod 9 to move, thereby causing the endoscope 4 and the ring laser generator 1 to move along the axis of the deep blind hole.

[0027] like Figures 4-6 The diagram illustrates a deep hole detection device based on optical principles used in this embodiment to detect deep blind holes. As the push rod 9 advances the entire detection head, including the ring laser generator 1, rotating mirror 2, and endoscope 4, towards the deep blind hole workpiece 5, the ring laser continuously propels forward along the inner wall of the hole to the bottom. This allows the acquisition of point cloud coordinates of the entire inner wall of the deep blind hole. Based on these point cloud coordinates, multiple geometric features of the deep blind hole can be obtained, including parameters such as hole diameter, taper, and bottom radius. Furthermore, the device also calculates aggregate features such as roundness and straightness of the deep blind hole.

[0028] Specifically, such as Figure 4 As shown, when the ring laser advances along the interior of the deep blind hole to the cylindrical section, the corresponding aperture size can be obtained by fitting the ring point cloud coordinates at any position on the cylindrical section; for example... Figure 5As shown, when the ring laser advances along the interior of the deep blind hole to the conical section, the taper of the irregular hole wall can be calculated based on the taper definition by combining the detected hole diameters at multiple locations on the conical section and the corresponding travel distances; for example... Figure 6 As shown, when the ring laser advances along the interior of the deep blind hole to the bottom arc segment, the radius of the bottom arc of the irregular hole can be calculated using a fitting algorithm by detecting the hole diameter at multiple locations on the arc segment and combining this with the corresponding travel distance. Finally, when the ring laser illuminates the surface of the deep hole, the ring beam will gradually decrease in size, eventually forming a single point.

[0029] In this embodiment, the coordinate system corresponding to the three-dimensional coordinates of the point cloud at each position can be unified according to the distance the detection head moves, so as to obtain the three-dimensional point cloud coordinates under the same coordinate system. Then, the bottom morphology of the irregular deep blind hole can be reconstructed according to the interpolation method or other fitting algorithm.

[0030] Example 2 like Figure 7 As shown, Embodiment 2 of the present invention provides a deep hole detection device based on optical principles. Similar to Embodiment 1, it includes a detection head and a calculation unit. The detection head includes a ring laser generator 1, a rotating surface mirror 2, an endoscope 4, and a calculation unit. The endoscope 4 is fixedly connected to the ring laser generator 1. Both the ring laser generator 1 and the rotating surface mirror 2 are coaxially arranged with the deep blind hole. The ring laser emitted by the ring laser generator 1 is reflected by the rotating surface mirror 2, converges at a point, and then diverges to irradiate the inner wall of the deep blind hole, thereby acquiring the ring laser image on the inner wall of the deep blind hole and sending it to the calculation unit. The calculation unit is used to calculate the point cloud coordinates of the cross-section of the deep blind hole based on the ring laser image on the inner wall of the deep blind hole, and to calculate the geometric features of the deep blind hole based on the point cloud coordinates.

[0031] Unlike Embodiment 1, in this embodiment, the rotating surface mirror 2 and the ring laser generator 1 are not fixedly connected, but can slide along the axial direction. During measurement, the rotating surface mirror 2 and the endoscope 4 are fixed, while the rotating surface mirror 2 moves along the axis 5 of the deep blind hole workpiece.

[0032] Furthermore, this embodiment also includes a driving mechanism. The rotating surface mirror 2 is disposed on the outer periphery of the ring laser generator 1 and is slidably connected to the ring laser generator 1. The driving mechanism is used to drive the rotating surface mirror 2 to move relative to the ring laser generator 1 along the axial direction of the deep blind hole.

[0033] like Figure 7As shown in this embodiment, as the rotating surface reflector 2 moves away from the deep blind hole workpiece 5, the ring laser can also be adjusted to move along the bottom of the deep blind hole until the convergence point of the ring laser moves to the bottom of the hole, thereby realizing the scanning of all positions of the deep blind hole and obtaining the point cloud coordinates of the hole wall.

[0034] Similar to Embodiment 1, in this embodiment, when calculating the point cloud coordinates using the above formulas (3) and (4), it is also necessary to calibrate the distance d between the convergence point of the ring laser and the origin of the coordinate system. Specifically, when the rotating surface reflector 2 is a conical reflector, the formula for calculating d is: d=d0+L*sinα2cos(2α1-2α2) / [sin(α1-α2)sinα]; (5) Where α1 represents the angle between the direction of the ring laser emitted by the ring laser generator 1 and the direction of the axis of the deep blind hole, α2 represents half of the apex angle of the rotating surface mirror 2, L represents the moving distance of the rotating surface mirror 2, and d0 represents the distance between the convergence point of the ring laser and the origin of the coordinate system before the rotating surface mirror 2 moves. α2=(α-α1) / 2.

[0035] Furthermore, in this embodiment, the rotating surface mirror 2 is a variable taper conical mirror. For example, a spherical mirror or a parabolic mirror. In this case, the values ​​of d and α are related to the moving distance L of the rotating surface mirror 2. The correspondence between d and α and the moving distance L of the rotating surface mirror 2 can be obtained in advance through experimental calibration, d(L) and α(L). Then, the point cloud coordinates are calculated by combining the above formulas (3) and (4). Specifically, the calculation formula is: x= d(L)*tanα(L) / (tanα(L)-tanθ); (6) y=d(L)*tanα(L)*tanθ / (tanα(L)-tanθ); (7) Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d(L) represents the distance between the convergence point of the ring laser and the origin of the coordinate system when the laser moves a distance L; α(L) represents half of the emission angle of the ring laser when the laser moves a distance L; and θ represents the field of view direction angle of the endoscope.

[0036] In this embodiment, by setting the rotating surface reflector (2) as a variable taper conical surface reflector, the irradiation position of the ring laser on the inner wall of the deep blind hole can be moved significantly with a small moving distance.

[0037] Example 3 Embodiment 3 of the present invention provides a deep hole detection method based on optical principles, implemented using the device described in Embodiment 1, and includes the following steps: Step 1: Drive the endoscope 4 and the ring laser generator 1 to move along the axis of the deep blind hole, and acquire the ring laser image on the inner wall of the deep blind hole through the endoscope 4; Step 2: Calculate the point cloud coordinates of the deep blind hole cross section based on the ring laser image at each location, and unify the coordinate system according to the moving distance of the ring laser generator 1 to obtain the final point cloud coordinates of the deep blind hole cross section at each location. Step 3: Calculate the geometric features of the deep blind hole based on the final point cloud coordinates.

[0038] Example 4 Embodiment 4 of the present invention provides a deep hole detection method based on optical principles, implemented using the device described in Embodiment 2, and includes the following steps: Step 1: Drive the rotating surface mirror 2 to move along the axis of the deep blind hole, so that the ring laser emitted by the ring laser generator 1 irradiates different cross-sectional positions of the deep blind hole until the ring laser irradiates the bottom of the deep blind hole; and collect the ring laser image on the inner wall of the deep blind hole through the endoscope 4. Step 2: Calculate the point cloud coordinates of the deep blind hole section based on the annular laser images at each location; Step 3: Calculate the geometric features of the deep blind hole based on the point cloud coordinates.

[0039] Furthermore, this embodiment also includes a step of calibrating the relationship between the moving distance of the rotating surface mirror 2 and the distance d between the convergence point of the ring laser and the origin of the coordinate system. The specific method of step two is to calculate the point cloud coordinates of the deep blind hole section by calculating the ring laser image at each position based on the relationship between the moving distance L of the rotating surface reflector (2), the distance d between the convergence point of the ring laser and the origin of the coordinate system, and half of the emission angle α of the ring laser, d(L) and α(L). The calculation formulas are the above formulas (6) and (7).

[0040] In this embodiment, since the endoscope 4 is fixed, the point cloud coordinates of the deep blind hole section calculated in step two are located in the same coordinate system, so there is no need to perform the coordinate system step one.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A deep hole detection device based on optical principles, characterized in that, include: The detection head and the computing unit include a ring laser generator (1), a rotating surface mirror (2), and an endoscope (4). The endoscope (4) is fixedly connected to the ring laser generator (1). The ring laser generator (1) and the rotating surface mirror (2) are both coaxially arranged with the deep blind hole. The ring laser emitted by the ring laser generator (1) is reflected by the rotating surface mirror (2), and then converges to a point before diverging to irradiate the inner wall of the deep blind hole. This is used to collect the ring laser image on the inner wall of the deep blind hole and send it to the calculation unit. The calculation unit is used to calculate the point cloud coordinates of the cross section of the deep blind hole based on the ring laser image on the inner wall of the deep blind hole, and to calculate the geometric features of the deep blind hole based on the point cloud coordinates.

2. The deep hole detection device based on optical principles according to claim 1, characterized in that, With the center of the endoscope (4) as the origin and the axis of the deep blind hole as the x-axis, the formula for calculating the point cloud coordinates is as follows: x= d*tanα / (tanα-tanθ); y=d*tanα*tanθ / (tanα-tanθ); Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d represents the distance between the convergence point of the ring laser and the origin of the coordinate system; α represents half of the emission angle of the ring laser; and θ represents the field of view angle of the endoscope.

3. The deep hole detection device based on optical principles according to claim 1, characterized in that, It also includes a connecting sleeve (3), through which the ring laser generator (1) is fixedly connected to the endoscope (4).

4. The deep hole detection device based on optical principles according to claim 1, characterized in that, The rotating surface reflector (2) is a conical surface reflector with a fixed taper, and the rotating surface reflector (2) is fixedly connected to the ring laser generator (1).

5. A deep hole detection device based on optical principles according to claim 4, characterized in that, It also includes an electric slide (8), on which a push rod (9) is provided, and the push rod (9) is fixedly connected to the ring laser generator (1); the electric slide (8) is used to push the push rod (9) to move, thereby causing the endoscope (4) and the ring laser generator (1) to move along the axis of the deep blind hole.

6. The deep hole detection device based on optical principles according to claim 1, characterized in that, The rotating surface reflector (2) is a variable taper conical surface reflector.

7. A deep hole detection device based on optical principles according to claim 6, characterized in that, It also includes a drive mechanism. The rotating surface mirror (2) is disposed on the outer periphery of the ring laser generator (1) and is slidably connected to the ring laser generator (1). The drive mechanism is used to drive the rotating surface mirror (2) to move relative to the ring laser generator (1) along the axis of the deep blind hole.

8. A deep hole detection method based on optical principles, implemented using the device described in claim 5, characterized in that, Includes the following steps: Step 1: Drive the endoscope (4) and the ring laser generator (1) to move along the axis of the deep blind hole, and collect the ring laser image on the inner wall of the deep blind hole through the endoscope (4); Step 2: Calculate the point cloud coordinates of the deep blind hole section based on the ring laser image at each location, and unify the coordinate system according to the moving distance of the ring laser generator (1) to obtain the final point cloud coordinates of the deep blind hole section at each location. Step 3: Calculate the geometric features of the deep blind hole based on the final point cloud coordinates.

9. A deep hole detection method based on optical principles, implemented using the device described in claim 7, characterized in that, Includes the following steps: Step 1: Drive the rotating surface mirror (2) to move along the axis of the deep blind hole, so that the ring laser emitted by the ring laser generator (1) irradiates different cross-sectional positions of the deep blind hole until the ring laser irradiates the bottom of the deep blind hole; collect the ring laser image on the inner wall of the deep blind hole through the endoscope (4); Step 2: Obtain the annular laser image at each location and calculate the point cloud coordinates of the deep blind hole section; Step 3: Calculate the geometric features of the deep blind hole based on the point cloud coordinates.

10. The deep hole detection method based on optical principles according to claim 9, characterized in that, It also includes the steps of calibrating the relationship between the moving distance L of the rotating surface mirror (2), the distance d between the convergence point of the ring laser and the origin of the coordinate system, and half of the emission angle α of the ring laser, d(L) and α(L); In step two, based on the relationship between the moving distance L of the rotating reflector (2), the distance d between the convergence point of the ring laser and the origin of the coordinate system, and half of the emission angle α of the ring laser, the point cloud coordinates of the deep blind hole section are calculated from the ring laser image at each position. The calculation formula is as follows: x= d(L)*tanα(L) / (tanα(L)-tanθ); y=d(L)*tanα(L)*tanθ / (tanα(L)-tanθ); Where x and y represent the horizontal and vertical coordinates of the point cloud, respectively; d(L) represents the distance between the convergence point of the ring laser and the origin of the coordinate system when the laser moves a distance L; α(L) represents half of the emission angle of the ring laser when the laser moves a distance L; and θ represents the field of view direction angle of the endoscope.

Images