Fisheye image-based depth measurement device for scene structure

Abstract

A depth measurement device for scene structure based on fisheye images is disclosed. [Solution] The depth measuring device is equipped with a mounting base 1, a mounting groove 2 is opened at the front end of the mounting base, and two fisheye lenses 4 are fixedly connected to the front end of the mounting base. A housing 5 is fitted onto the outside of the fisheye lenses, and position regulating units are attached to both sides of the housing. Fixed bases 9 are fixedly connected to both sides of the mounting base, and slide grooves are opened on the outside of the fixed bases. The position regulating units cooperate with the fixed bases, position regulating clamp blocks 11, springs, tension rods and tension blocks to form a rapid clamp position regulating structure, enabling rapid attachment and detachment of the housing without the use of tools.

Description

Technical Field

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[0003]

[0001] The present invention relates to the technical field of measuring devices, and particularly to a depth measuring device for scene structure based on fisheye images.

Background Art

[0002] Fisheye lenses have the advantages of ultra-wide-angle and panoramic imaging, and are widely applied in fields such as scene 3D reconstruction, spatial depth measurement, intelligent monitoring, and autonomous driving environment recognition. When measuring the depth of a scene structure using binocular fisheye images, the spatial distance and 3D shape are calculated by binocular disparity and stereo matching algorithms, featuring a wide imaging range, simple arrangement, and high measurement efficiency.

[0003] In conventional measuring devices, the fisheye lens is directly exposed to the outside when not in use and does not have a dedicated protection structure. Therefore, it is easily subject to external force collisions and dust contamination, leading to lens damage and a decrease in imaging accuracy. In order to solve the drawbacks existing in the prior art, the present invention proposes a depth measuring device for scene structure based on fisheye images.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The object of the present invention is to provide a depth measuring device for scene structure based on fisheye images in order to solve the drawbacks existing in the prior art.

Means for Solving the Problems

[0005] To achieve the above object, the present invention adopts the following technical means. A depth measuring device for scene structure based on a fisheye image, comprising a mounting base. A mounting groove is opened at the front end of the mounting base, and two fisheye lenses are fixedly connected to the front end of the mounting base. A housing is fitted to the outside of the fisheye lenses, and position regulating units are attached to both sides of the housing. Fixed bases are fixedly connected to both sides of the mounting base, and a sliding groove is opened on the outside of the fixed base. Two position regulating clamp blocks are slidably connected within the sliding groove, and support blocks are fixedly connected to both sides of the outside of the fixed base. A tension rod passes through and is slidably connected within the support blocks. An image sensor is fixedly connected to the center of the rear end of the mounting base, a distortion correction / stereo matching module is fixedly connected to the upper left of the rear end of the mounting base, and a calibration parameter storage module is fixedly connected to the lower left of the rear end of the mounting base.

[0006] Further explanation of the above technical solution is provided that the position regulating unit includes a connecting block, which is fixedly connected to the housing. A connecting rod is fixedly connected to the inside of the connecting block, and a position regulating plug block is fixedly connected to the end of the connecting rod.

[0007] As a further explanation of the above technical solution, the mounting groove corresponds to the housing, and a seal ring is fixedly connected within the mounting groove.

[0008] As a further explanation of the above technical solution, one adjacent side of each of the two tension rods is fixedly connected to a position-regulating clamp block.

[0009] As a further explanation of the above technical solution, a spring is fitted onto the outer circumference of the tension rod, and the spring is positioned between the support block and the position-regulating clamp block.

[0010] As a further explanation of the above technical solution, a tension block is fixedly connected to one outer end of the tension rod.

[0011] As a further explanation of the above technical solution, a processor is fixedly connected to the right rear end of the mounting base.

[0012] As a further explanation of the above technical solution, the position-regulating plug block is positioned between the two position-regulating clamp blocks. [Effects of the Invention]

[0013] This invention has the following beneficial effects. In this invention, a rapid clamp position regulating structure is formed through the cooperation of a position regulating unit (connecting block, connecting rod, position regulating plug block), a fixed base, a position regulating clamp block, a spring, a tension rod, and a tension block. This enables rapid attachment and detachment of the housing without the use of tools. By placing a seal ring in the mounting groove, after the housing is fitted into the mounting groove, the seal ring adheres tightly to the housing, forming a sealed protective structure. This effectively blocks the intrusion of dust and water vapor, providing dustproof and moisture-proof effects. Furthermore, when the device is not in use, the housing is directly fitted to the outside of the fisheye lens, completely covering the lens and achieving all-around external protection for the lens. This effectively solves the dual problems of insufficient sealing and insufficient protection when not in use in conventional devices, ensuring the integrity of the lens and subsequent imaging accuracy. [Brief explanation of the drawing]

[0014] [Figure 1] A perspective view of a depth measuring device for a scene structure based on a fisheye image according to the present invention. [Figure 2] An exploded view of the depth measurement device for a scene structure based on a fisheye image according to the present invention. [Figure 3] A schematic diagram of the position regulating clamp block structure of the depth measuring device for a scene structure based on a fisheye image according to the present invention. [Figure 4] Rear view of the mounting base for the depth measuring device for a scene structure based on a fisheye image according to the present invention. [Explanation of Symbols]

[0015] 1: Mounting base; 2: Mounting groove; 3: Seal ring; 4: Fisheye lens; 5: Housing; 6: Connecting block; 7: Connecting rod; 8: Position regulating plug block; 9: Fixing base; 10: Sliding groove; 11: Position regulating clamp block; 12: Support block; 13: Tension rod; 14: Spring; 15: Tension block; 16: Image sensor; 17: Processor; 18: Calibration parameter memory module; 19: Distortion correction / stereo matching module. [Modes for carrying out the invention]

[0016] The following describes the technical means in the embodiments of the present invention clearly and completely, with reference to the drawings of the embodiments. Note that the embodiments described are only a selection of the present invention, not all embodiments. All other embodiments that a person skilled in the art could obtain without creative work based on the embodiments of the present invention fall within the scope of the present invention.

[0017] In the description of this invention, directions or positional relationships indicated by terms such as "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the directions or positional relationships shown in the drawings and are solely for the purpose of describing and simplifying the description of this invention. They do not indicate or imply that the device or element has a specific direction, or that it must be configured and operate in a specific direction. Therefore, they should not be understood as limiting this invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. Furthermore, unless otherwise clearly defined and limited, the terms "attachment," "connection," and "linking" are understood in a broad sense. For example, it may be a fixed connection, a removable connection, or an integral connection. It may be a mechanical connection or an electrical connection. It may be a direct connection, an indirect connection via an intermediate medium, or internal communication between two elements. Those skilled in the art will understand the specific meaning of the above terms in this invention depending on the specific situation.

[0018] Referring to Figures 1 to 4, an embodiment of the present invention: a depth measuring device for a scene structure based on a fisheye image includes a mounting base (1). A mounting groove (2) is opened at the front end of the mounting base (1), and two fisheye lenses (4) are fixedly connected to the front end of the mounting base (1). A housing (5) is fitted outside the fisheye lenses (4), and position regulating units are attached to both sides of the housing (5). Fixed bases (9) are fixedly connected to both sides of the mounting base (1), and a sliding groove (10) is opened on the outside of the fixed base (9). Two position regulating clamp blocks (11) are slidably connected within the sliding groove (10), and support blocks (12) are fixedly connected to both sides of the outside of the fixed base (9). A tension rod (13) passes through and is slidably connected within the support block (12). An image sensor (16) is fixedly connected to the center of the rear end of the mounting base (1), a distortion correction / stereo matching module (19) is fixedly connected to the upper left rear end of the mounting base (1), and a calibration parameter storage module (18) is fixedly connected to the lower left rear end of the mounting base (1).

[0019] Specifically, the overall structure mainly uses a mounting base 1 formed by integral machining of an aluminum alloy as the main support structure. The outer shape of the mounting base 1 is an oval block, with a length of 120 mm, a width of 80 mm, and a thickness of 25 mm. Its surface is treated with hard anodizing, and the surface roughness Ra ≤ 0.8 μm, providing good structural strength and corrosion resistance, enabling long-term stable use indoors and outdoors. At the center position of the front end of the mounting base 1, a mounting groove 2 is opened. The fitting surface between the inner wall of the mounting groove 2 and the housing 5 is machined by precision milling, and the coaxiality error ≤ 0.02 mm. A fluororubber sealing ring 3 is fitted inside the mounting groove 2. The cross-section of the sealing ring 3 is oval, with a shore hardness of 60 ± 5 HA and a compression rate of 30% - 40% after assembly, achieving IP54-class dust and waterproof performance, effectively blocking the intrusion of dust and water vapor to protect the fisheye lens 4. At the front end of the mounting base 1, two fisheye lenses 4 with a size of 1 / 2.3 inch, a focal length of 1.05 mm, and an angle of view of 190° are symmetrically fixed. The center distance (baseline length) between the two lenses is 60 mm, and the parallelism error of the optical axes after assembly ≤ 0.1°, stabilizing the geometric relationship of binocular imaging. Outside the fisheye lens 4, a housing 5 made of ABS engineering plastic injection molding is externally fitted. The housing 5 has a cover-like structure with a closed front end and an open rear end. The gap between the inner wall and the outer periphery of the lens is uniformly 0.5 mm, completely covering the lens to achieve all-round protection.

[0020] Fixing bases 9 are integrally formed on both the left and right sides of the mounting base 1. The fixing base 9 has a length of 50 mm, a width of 20 mm, and a thickness of 15 mm. On the outside, slide grooves 10 with a width of 6 mm and a depth of 5 mm are opened. Two POM position-regulating clamp blocks 11 are slidably assembled in the slide grooves 10. One adjacent side of the position-regulating clamp block 11 is inclined, and a locking groove for facilitating the regulation of the position-regulating plug block 8 is opened inside. The fitting gap between the position-regulating clamp block 11 and the slide groove 10 ≤ 0.05 mm, and the sliding is smooth without jamming. Support blocks 12 are integrally provided on both sides of the outer end of the fixing base 9. At the center of the support block 12, a guide hole with a diameter of 3.2 mm is opened, which is used for the insertion of the tension rod 13.

[0021] The tension rod 13 is made of SUS304 stainless steel, with a diameter of 3 mm, a length of 40 mm, its surface is polished, and the sliding clearance with the support block 12 is ≤ 0.02 mm. A stainless steel compression spring 14 is externally fitted on the outer periphery of the tension rod 13. The spring 14 has a wire diameter of 0.5 mm, an outer diameter of 6 mm, a free length of 12 mm, a spring constant of 0.5 N / mm, and the preload force after assembly is 2 N, ensuring that the position regulation clamp block 11 stably holds the position regulation plug block 8. A tension block 15 is screwed to the outer end of the tension rod 13. The tension block 15 is a butterfly-shaped plastic part, suitable for manual operation. The image sensor 16 adopts a SONY IMX415 CMOS sensor, with a size of 1 / 2.3 inch, 8 million effective pixels, a frame rate of 30 fps, corresponding to a wide dynamic range, is mounted at the center position of the rear end, and the image plane distance from the fisheye lens 4 is accurately aligned at 12 mm. The calibration parameter storage module 18 adopts a W25Q128 flash memory chip, with a storage capacity of 128 Mbit, and can store calibration data such as internal lens parameters, external parameters, and distortion coefficients for a long time. The distortion correction and stereo matching module 19 adopts an FPGA EP4CE10, realizes real-time correction of image distortion and binocular stereo matching, and the processing delay is ≤ 50 ms.

[0022] The position regulation unit includes a connecting block 6, and the connecting block 6 is fixedly connected to the housing 5. A connecting rod 7 is fixedly connected inside the connecting block 6, and a position regulation plug block 8 is fixedly connected to the end of the connecting rod 7. The position regulation plug block 8 is arranged between two position regulation clamp blocks 11.

[0023] Specifically, the position regulation units are symmetrically mounted on both the left and right sides of the housing 5. The position regulation unit includes a connecting block 6, a connecting rod 7, and a position regulation plug block 8 made of PA66. The connecting block 6 is fixed to the outer wall of the housing 5 by thermal welding. The connecting rod 7 has a diameter of 3 mm and a length of 15 mm, and the position regulation plug block 8 is hemispherical and suitable for guiding and inserting.

[0024] Mounting groove 2 corresponds to housing 5, and a seal ring 3 is fixedly connected within mounting groove 2. One adjacent end of each of the two tension rods 13 is fixedly connected to position regulating clamp block 11. A spring 14 is fitted onto the outer circumference of the tension rod 13, and the spring 14 is positioned between the support block 12 and the position regulating clamp block 11. A tension block 15 is fixedly connected to one outer end of the tension rod 13. A processor 17 is fixedly connected to the rear right end of mounting base 1. The processor 17 employs an STM32H750 high-performance microcontroller with a main frequency of 400MHz, equipped with floating-point arithmetic and high-speed data processing functions, and is responsible for overall timing control and depth calculation.

[0025] Operating principle: Protection principle when not in use: When the device is not in use, the housing 5 is placed over the outside of the fisheye lens 4. The housing 5 completely covers the fisheye lens 4, preventing damage to the lens from dust, water vapor, external impacts, etc. This provides external protection for the fisheye lens 4, ensures subsequent imaging accuracy, and extends the service life of the device.

[0026] Mounting and Fixing Principle: The housing 5 is aligned with the mounting groove 2 and inserted. At this time, the connecting rods 7 on both sides and the position-regulating plug block 8 are aligned and inserted between the two position-regulating clamp blocks 11. When the position-regulating plug block 8 is inserted into the two position-regulating clamp blocks 11, the two position-regulating clamp blocks 11 are pressed and slide back and forth within the slide groove 10, compressing the spring 14. After the position-regulating plug block 8 enters the position-regulating clamp block 11, the spring 14 returns to its original position, causing the two position-regulating clamp blocks 11 to move relative to each other again, regulating the position-regulating plug block 8, and completing the fixing and mounting of the housing 5. If removal is necessary, the tension block 15 is pulled by hand, moving the tension rod 13 and the position-regulating clamp block 11, and releasing the restriction on the position-regulating plug block 8. This allows the position-regulating plug block 8 to be easily removed from between the two position-regulating clamp blocks 11.

[0027] Image acquisition principle: When the device is started, two fisheye lenses 4 operate synchronously to acquire a raw image of the scene with an ultra-wide field of view. The acquired image signal is transmitted to an image sensor 16 located at the center of the rear end of the mounting base 1. The image sensor 16 performs photoelectric conversion to convert the analog image signal into a digital signal, and also performs rudimentary signal filtering on the raw image to provide clear and stable image data for subsequent processing.

[0028] Data Processing Principle: The digital image signal processed by the image sensor 16 is transmitted to the distortion correction / stereo matching module 19 located on the upper left rear end of the mounting base 1. The calibration parameter memory module 18 located on the lower left rear end of the mounting base 1 has calibration data such as the internal parameters (focal length, pixel size), external parameters (relative orientation of both lenses, rotation matrix, translation vector), and distortion coefficient of the fisheye lens 4 stored in advance. The distortion correction / stereo matching module 19 retrieves the above parameters and corrects the barrel distortion of the fisheye image with high precision, restoring the true geometric relationship of the scene. Subsequently, stereo matching processing is performed on the corrected binocular fisheye image to extract corresponding feature points in the scene, calculate the pixel parallax between the corresponding points, and complete the generation of the parallax diagram.

[0029] Depth Measurement Principle: The processor 17 located on the right rear end of the mounting base 1 comprehensively controls the coordinated operation of each module and receives parallax data output by the distortion correction / stereo matching module 19. Combining parameters such as the baseline length and focal length of the binocular fisheye lenses 4, the depth measurement algorithm (Z = B·f / d, where Z is depth, B is baseline length, f is focal length, and d is parallax) calculates the depth information of each point in the scene on a pixel-by-pixel basis. Finally, the processor 17 combines the depth information and pixel coordinates, generates a 3D point cloud of the scene by back projection, and restores the complete scene spatial structure, distance dimensions, and 3D shape, completing the depth measurement work of the scene structure.

[0030] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and does not limit it. Although the present invention has been described in detail with reference to the embodiments described above, those skilled in the art can modify the technical means described in each of the embodiments above, or substitute some of the technical features thereof. All modifications, substitutions, improvements, etc., made within the spirit and principles of the present invention are all within the scope of protection of the present invention.

Claims

1. A depth measuring device for a scene structure based on a fisheye image, comprising a mounting base (1), a mounting groove (2) opening at the front end of the mounting base (1), two fisheye lenses (4) fixedly connected to the front end of the mounting base (1), a housing (5) fitted outside the fisheye lenses (4), position regulating units attached to both sides of the housing (5), fixed bases (9) fixedly connected to both sides of the mounting base (1), a slide groove (10) opening on the outside of the fixed base (9), two position regulating clamp blocks (11) slidably connected within the slide groove (10), support blocks (12) fixedly connected to both sides of the outside of the fixed base (9), and a tension rod (13) passing through and slidably connected within the support blocks (12). An image sensor (16) is fixedly connected to the center of the rear end of the mounting base (1), a distortion correction / stereo matching module (19) is fixedly connected to the upper left rear end of the mounting base (1), and a calibration parameter storage module (18) is fixedly connected to the lower left rear end of the mounting base (1). A depth measuring device for scene structure based on a fisheye image, characterized by the above.

2. The position regulating unit includes a connecting block (6), the connecting block (6) is fixedly connected to the housing (5), a connecting rod (7) is fixedly connected to the inside of the connecting block (6), and a position regulating plug block (8) is fixedly connected to the end of the connecting rod (7). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

3. The mounting groove (2) corresponds to the housing (5), and a seal ring (3) is fixedly connected within the mounting groove (2). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

4. One adjacent side of each of the two tension rods (13) is fixedly connected to the position-regulating clamp block (11). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

5. A spring (14) is fitted onto the outer circumference of the tension rod (13), and the spring (14) is positioned between the support block (12) and the position regulating clamp block (11). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

6. A tension block (15) is fixedly connected to one outer end of the tension rod (13). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

7. A processor (17) is fixedly connected to the right rear end of the mounting base (1). A depth measuring device for a scene structure based on a fisheye image, as described in claim 1.

8. The position-regulating plug block (8) is positioned between the two position-regulating clamp blocks (11). A depth measuring device for a scene structure based on a fisheye image, as described in claim 2.

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