Long-baseline deep-sea binocular measurement camera

Abstract

The invention discloses a long-baseline deep-sea binocular measurement camera which comprises a control cabin, a deep-sea camera and a double-rod supporting assembly. The control cabin is used for camera control and a storage circuit; pressure-resistant fastening assemblies are symmetrically mounted at the two ends of the control cabin; the number of the deep sea cameras is two. The two deep sea cameras are installed at the ends, away from the control cabin, of the two pressure-resistant fastening assemblies correspondingly. The optical axes of the two deep sea cameras are located on the same plane, and the included angle between the two optical axes is 180 degrees to 2 alpha. The two deep sea cameras are electrically connected with the control cabin; the double-rod supporting assembly is installed between the two deep sea cameras. According to the invention, the binocular measurement camera has a long base line, can obtain a large public field of view, is small in deformation and stable in structure in a deep sea high-pressure environment, guarantees the constancy of internal and external parameters of the binocular measurement camera in the measurement process, and improves the measurement precision and accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of binocular cameras, and in particular to a long-baseline deep-sea binocular measurement camera. Background Art

[0002] Because deep-sea creatures are difficult to capture, most studies on them use deep-sea cameras or cameras to record or take pictures. Binocular cameras can simulate the way humans observe the world with two eyes, using two cameras to obtain two images of the same scene from different perspectives, and use computer vision algorithms to calculate the parallax between the two images to obtain three-dimensional information about objects in the scene, including key data such as depth and size. However, binocular vision technology is difficult to apply to the deep sea.

[0003] First, the binocular measurement algorithm needs to calibrate the two cameras, determine their internal and external parameters, establish a coordinate system, and then calculate the three-dimensional coordinates of the objects in the scene. For the measurement of deep-sea organisms and other targets, a viewing distance of 1-5 meters is usually required. Therefore, the binocular camera needs to have a long baseline to ensure the accuracy of the measurement, and the camera optical axis needs to form a certain angle to obtain a larger public field of view. At the same time, the accuracy of the angle will also affect the accuracy of the measurement. Since the calibration work is difficult to implement on-site in the deep sea, the usual practice is to calibrate in the shallow water environment before going to the deep sea for measurement. After completing the camera calibration, it is necessary to ensure that the internal and external parameters of the binocular camera remain unchanged. However, in the high-pressure environment of the deep sea, the conventional pressure cabin will be deformed under pressure, and the bending stress deformation of the connector and the force of the center of gravity will cause the position of the two cameras to shift, resulting in changes in the external parameters such as the baseline and measurement angle of the two cameras, which will cause a large error in the measurement results.

[0004] The Chinese patent with publication number CN212628104U discloses a deep-sea binocular stereo vision camera, but it is a short-baseline binocular camera that is difficult to measure at a long distance with high precision. The Chinese patent with publication number CN110260820A discloses an underwater binocular stereo vision measurement system that can be used in a high-pressure environment at a depth of 4,000 meters in the sea. It uses a dynamic reference coordinate system to eliminate the measurement error caused by vibration, and requires the deployment of four active cursor targets and a square aluminum profile frame. Therefore, it can only be loaded on a fixed platform in the deep sea, and is very limited in terms of usage scenarios.

[0005] Therefore, a long baseline deep-sea binocular measurement camera is proposed to structurally solve the problem of external parameter changes of binocular measurement cameras in deep-sea applications. Summary of the invention

[0006] The object of the present invention is to provide a long baseline deep-sea binocular measurement camera, aiming to solve or improve at least one of the above-mentioned technical problems.

[0007] To achieve the above object, the present invention provides the following solution: The present invention provides a long baseline deep-sea binocular measurement camera, comprising:

[0008] A control cabin, which is used for camera control and storage circuits; pressure-resistant fastening components are symmetrically installed at both ends of the control cabin;

[0009] A deep-sea camera, wherein two deep-sea cameras are provided; the two deep-sea cameras are respectively installed at one end of the two pressure-resistant fastening components away from the control cabin; the optical axes of the two deep-sea cameras are located in the same plane, and the angle between the two optical axes is 180°-2α; the two deep-sea cameras are electrically connected to the control cabin;

[0010] A double-rod support assembly is installed between the two deep-sea cameras.

[0011] According to a long baseline deep-sea binocular measurement camera provided by the present invention, the deep-sea camera comprises a camera cabin end cover, a camera cabin body, a camera movement, a pressure-bearing optical lens and a lens cover;

[0012] The camera compartment end cover is cylindrical and one side is cut into a rectangular plane, a camera axis hole is vertically opened on the rectangular plane, the camera axis hole is connected to the inside of the camera compartment body, and the angle between the camera axis hole and the central axis of the camera compartment body is α;

[0013] An inner flange is provided on the inner side wall of the camera cabin, and the inner flange is integrally formed with the camera cabin; the camera movement is installed on the inner flange; the pressure-bearing optical lens is installed on the side of the camera cabin away from the camera cabin end cover, and the lens cover is installed on the side of the pressure-bearing optical lens away from the camera cabin end cover; the camera cabin end cover is rigidly connected to the pressure-resistant fastening assembly; the double-rod support assembly is detachably connected to the camera cabin; and both camera movements are electrically connected to the control cabin.

[0014] According to a long baseline deep-sea binocular measurement camera provided by the present invention, the pressure-resistant fastening assembly includes a pressure-resistant straight tube, a rectangular flange and a circular flange; O-ring grooves are provided at both ends of the pressure-resistant straight tube, and O-rings are installed in the O-ring grooves; the rectangular flange and the circular flange are respectively vertically fixed to the two ends of the outer wall of the pressure-resistant straight tube; one end of the pressure-resistant straight tube is plugged into the camera shaft hole, and is fixedly connected to the camera cabin end cover through the rectangular flange; the other end of the pressure-resistant straight tube is plugged into the control cabin, and is fixedly connected to the control cabin through the circular flange.

[0015] According to a long baseline deep-sea binocular measurement camera provided by the present invention, the double-rod support assembly includes a support rod, a reinforcing rod and a bolt; two support rods are provided, and a plurality of reinforcing rods and a plurality of bolts are provided; the two camera cabins are installed at both ends of the support rods through the bolts, and the two support rods are respectively located at the top and bottom of one side of the camera cabin close to the lens cover; the reinforcing rod is detachably connected between the two support rods through the bolts.

[0016] According to a long baseline deep-sea binocular measurement camera provided by the present invention, a reinforcement ring is provided on the outer side wall of the camera cabin, and the reinforcement ring and the inner flange are integrally formed with the camera cabin; the reinforcement ring and the inner flange are located on the same plane.

[0017] According to the long baseline deep sea binocular measurement camera provided by the present invention, the angle α is calculated according to the formula Obtain, l represents the baseline length between the two camera movements, and u represents the object distance between the camera movement and the object to be measured.

[0018] According to a long baseline deep-sea binocular measurement camera provided by the present invention, the control cabin includes a control cabin body, control cabin end covers are respectively installed at both ends of the control cabin body, a control cabin axial hole is opened on the control cabin end cover, one end of the pressure-resistant straight pipe close to the circular flange is plugged into the control cabin axial hole, and the circular flange is fixedly connected to the control cabin end cover; a control system is installed in the control cabin body, and the deep-sea camera is electrically connected to the control system through a cable, and the cable is arranged in the pressure-resistant straight pipe.

[0019] According to a long baseline deep-sea binocular measurement camera provided by the present invention, fixing seats are respectively installed on the outer side walls at both ends of the control cabin body, and the two fixing seats are located between the two control cabin end covers; the fixing seats are semicircular sleeve clamps made of electrochemically inert plastic.

[0020] The present invention discloses the following technical effects:

[0021] The present invention installs the deep-sea cameras on both sides of the control cabin through a pressure-resistant fastening assembly, thereby ensuring that the deep-sea binocular measurement camera has a long baseline and can obtain a large position difference of the target to be measured, thereby ensuring the accuracy of binocular vision long-distance measurement; after the two deep-sea cameras are installed, the optical axes are on the same plane, and the two optical axes converge on the observation target, so that the binocular measurement cameras obtain a larger common field of view, thereby enabling the two deep-sea cameras to simultaneously capture more feature points of the target to be measured, thereby improving the accuracy of the binocular measurement camera in positioning and measuring the target to be measured; the connection structure of the entire device is free of bending, thereby eliminating the deformation caused by stress generated by the deep-sea high pressure on the curved structure, thereby ensuring that the external parameters of the binocular camera do not change with the change of water depth after calibration, thereby ensuring the accuracy of the measurement result, and also protecting the safety of the electrical connection between the deep-sea camera and the control cabin;

[0022] The present invention eliminates the torque generated by the fact that the center of gravity of the two deep-sea cameras and the center of gravity of the control cabin are not in the same straight line by installing a double-rod support assembly between the two deep-sea cameras, thereby ensuring the stability of the relative positions of the two deep-sea cameras when operating under various working conditions in a deep-sea high-pressure environment, thereby ensuring the constancy of the internal and external parameters of the binocular measurement camera during the measurement process, and improving the accuracy of the measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 is an axonometric view of the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the deep-sea camera in the present invention;

[0026] Figure 3 It is a structural schematic diagram of the pressure-resistant fastener assembly in the present invention;

[0027] Figure 4 It is a schematic diagram of the structural force of the camera cabin optimized in the present invention;

[0028] Figure 5 It is a structural schematic diagram of the control cabin in the present invention;

[0029] Figure 6 is a cross-sectional view of the camera compartment end cover of the present invention;

[0030] Figure 7 It is a force diagram of the torque of the double rod support assembly in the present invention;

[0031] Figure 8 It is a force diagram of the load pressure of the double rod support assembly in the present invention;

[0032] Among them, 1. deep-sea camera; 11. camera cabin end cover; 111. camera axis hole; 112. end cover axis hole; 12. camera cabin body; 121. inner flange; 122. reinforcement ring; 13. camera movement; 14. lens cover; 15. pressure-bearing optical lens; 2. control cabin; 21. control cabin body; 22. control cabin end cover; 221. control cabin axis hole; 3. pressure-resistant fastening assembly; 31. pressure-resistant straight pipe; 32. rectangular flange; 33. circular flange; 34. O-ring groove; 4. double-rod support assembly; 41. support rod; 42. reinforcement rod; 43. bolt; 5. fixing seat. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Reference Figure 1-Figure 8 The present invention provides a long baseline deep-sea binocular measurement camera, comprising:

[0036] The control cabin 2 is used for camera control and storage circuits; pressure-resistant fastening components 3 are symmetrically installed at both ends of the control cabin 2; in this embodiment, the control cabin 2 is a cylindrical cabin made of titanium alloy material, which has good corrosion resistance and pressure resistance effects; a processor circuit for controlling the camera to start taking pictures and storing pictures is installed inside the control cabin 2;

[0037] Deep-sea camera 1, two deep-sea cameras 1 are provided; the two deep-sea cameras 1 are respectively installed at one end of the two pressure-resistant fastening components 3 away from the control cabin 2; the optical axes of the two deep-sea cameras 1 are located in the same plane, and the angle between the two optical axes is 180°-2α; the two deep-sea cameras 1 are electrically connected to the control cabin 2; in this embodiment, the optical axis angle of the two deep-sea cameras 1 is 39°, which is used to observe deep-sea organisms at a viewing distance of 1.5m in the deep-sea environment, and the fields of view of the two deep-sea cameras 1 are almost completely overlapped;

[0038] A double-rod support assembly 4, which is installed between two deep-sea cameras 1;

[0039] With such arrangement, the present invention installs the deep-sea camera 1 on both sides of the control cabin 2 through the pressure-resistant fastening assembly 3, thereby ensuring that the deep-sea binocular measurement camera has a longer baseline and can obtain a larger position difference of the target to be measured, thereby ensuring the accuracy of binocular vision long-distance measurement; after the two deep-sea cameras 1 are installed, the optical axes are on the same plane, and the two optical axes converge on the observation target, so that the binocular measurement camera obtains a larger common field of view, thereby enabling the two deep-sea cameras 1 to simultaneously capture more feature points of the target to be measured, thereby improving the accuracy of the binocular measurement camera in positioning and measuring the target to be measured; the connection structure of the entire device is free of bending, thereby eliminating the deformation caused by stress generated by the deep-sea high pressure on the curved structure, thereby ensuring that the external parameters of the binocular camera do not change with the change of water depth after calibration, thereby ensuring the accuracy of the measurement result, and also protecting the safety of the electrical connection between the deep-sea camera 1 and the control cabin 2;

[0040] The present invention eliminates the torque generated by the fact that the center of gravity of the two deep-sea cameras 1 and the center of gravity of the control cabin 2 are not in the same straight line by installing a double-rod support assembly 4 between the two deep-sea cameras 1, thereby ensuring the stability of the relative positions of the two deep-sea cameras 1 when operating under various working conditions in a deep-sea high-pressure environment, thereby ensuring the constancy of the internal and external parameters of the binocular measurement camera during the measurement process, and improving the accuracy of the measurement results.

[0041] Further optimizing the scheme, the deep-sea camera 1 comprises a camera cabin end cover 11, a camera cabin body 12, a camera movement 13, a pressure-bearing optical lens 15 and a lens cover 14; the camera cabin end cover 11 is cylindrical and one side is cut into a rectangular plane, a camera axis hole 111 is vertically opened on the rectangular plane, the camera axis hole 111 is connected to the inside of the camera cabin body 12, and the angle between the camera axis hole 111 and the central axis of the camera cabin body 12 is α;

[0042] An inner flange 121 is provided on the inner side wall of the camera cabin body 12, and the inner flange 121 is integrally formed with the camera cabin body 12; the camera movement 13 is installed on the inner flange 121; the pressure-bearing optical lens 15 is installed on the side of the camera cabin body 12 away from the camera cabin end cover 11, and the lens cover 14 is installed on the side of the pressure-bearing optical lens 15 away from the camera cabin end cover 11; the camera cabin end cover 11 is rigidly connected to the pressure-resistant fastening assembly 3; the double-rod support assembly 4 is detachably connected to the camera cabin body 12; both camera movements 13 are electrically connected to the control cabin 2;

[0043] In this embodiment, an end cover shaft hole 112 is provided on the end surface of the camera compartment end cover 11 close to the camera compartment body 12, and the camera shaft hole 111 is connected with the interior of the camera compartment body 12 through the end cover shaft hole 112, and the angle between the axis of the camera shaft hole 111 and the axis of the end cover shaft hole 112 is α;

[0044] In this embodiment, the camera movement 13 adopts an industrial camera with an unprocessed and compressed original image format (raw format) output function to ensure the accuracy of the measurement algorithm analysis; the pressure-bearing optical lens 15 adopts an artificial corundum optical lens, which has a very high pressure-bearing capacity while ensuring the transmittance of light; by setting the inner diameter of the lens cover 14 to be smaller than the pressure-bearing optical lens 15, the pressure-bearing optical lens 15 can be blocked and given a certain pre-tightening force, so that the sealing ring can be pressed to prevent water leakage in the deep-sea high-pressure environment, so that the deep-sea camera 1 has good sealing performance; the camera cabin end cover 11 is made of titanium alloy material, which has good pressure resistance and corrosion resistance.

[0045] Further optimizing the scheme, the pressure-resistant fastening assembly 3 includes a pressure-resistant straight tube 31, a rectangular flange 32 and a circular flange 33; O-ring grooves 34 are provided at both ends of the pressure-resistant straight tube 31, and O-rings are installed in the O-ring grooves 34; the rectangular flange 32 and the circular flange 33 are respectively and vertically fixed to the two ends of the outer wall of the pressure-resistant straight tube 31; one end of the pressure-resistant straight tube 31 is plugged into the camera shaft hole 111, and is fixed to the camera cabin end cover 11 through the rectangular flange 32; the other end of the pressure-resistant straight tube 31 is plugged into the control cabin 2, and is fixed to the control cabin 2 through the circular flange 33;

[0046] With such a configuration, the O-ring is used to prevent seawater from penetrating into the cabin; the two camera cores 13 form a long baseline binocular visual observation structure with a straight pipe fixed to the control cabin 2 through a pressure-resistant straight pipe 31, which, on the one hand, ensures the electrical connection between the control cabin 2 and the camera core 13 at normal pressure to achieve high-speed image data exchange, and on the other hand, ensures the stability of the positions of the two camera cores 13 under different water depth pressures. Compared with the bending design of the pipeline pressure-resistant pipe, the straight pipe fixed structure has a higher bending deformation strength, because the straight pipe is mainly subjected to force in the axial direction of the pipe, and the force is in the form of tension and compression. According to the principle of mechanics, the tensile stress and compressive stress are equal in magnitude; the curved pipe has a large stress in the bending direction, and there are also shear stress and axial stress. In the curved pipe, the smaller the radius of curvature, the greater the degree of bending, and the greater the stress. By respectively fixing the rectangular flange 32 and the circular flange 33 perpendicularly at both ends of the pressure-resistant straight pipe 31, the larger radial cross-sections of the rectangular flange 32 and the circular flange 33 are fastened with bolts, thereby enhancing the bending and shear strength of the connection points. Meanwhile, the large contact surface also enhances the tightness of the connection, thereby avoiding slippage caused by the gap between the control cabin 2 and the camera cabin end cover 11 and the pressure-resistant straight pipe 31 due to the radial seal, making it more suitable for deep-sea environments. Under the premise of realizing that the optical axis of the deep-sea camera 1 converges on the target to be measured and obtaining a large common field of view, the relative positions of the two deep-sea cameras 1 are fixed and stable.

[0047] Further optimized solution, the double rod support assembly 4 includes a support rod 41, a reinforcing rod 42 and a bolt 43; there are two support rods 41, and there are several reinforcing rods 42 and bolts 43; two camera cabins 12 are installed at both ends of the support rod 41 by bolts 43, and the two support rods 41 are respectively located at the top and bottom of the camera cabin 12 near the lens cover 14; the reinforcing rod 42 is detachably connected between the two support rods 41 by bolts 43; several reinforcing rods 42 can be installed vertically or any two of them form an X structure, or the two installation methods are combined; in this embodiment, it is preferred to vertically install several reinforcing rods 42 between the two support rods 41;

[0048] By installing the support rods 41 at the top and bottom of the camera assembly, the deformation problem caused by the center of gravity of the two camera assemblies and the center of gravity of the control cabin 2 not being in the same straight line is eliminated, making the structure of the binocular measurement camera more stable. Figure 7 As shown, in the single-point support structure, the camera cabin end cover 11 generates a torque M=L1F relative to the connection point of the pressure-resistant straight pipe 31; in the double-point support structure, the force support point of the camera cabin body 12 is changed to the force points at both ends of the original force arm. For example, when the pressure on the force point C is F C When the moment M is generated relative to point A A =L1F C , the force F of the support rod 41 C1 The opposite force F to point D D The force F of the support rod 41 D1 The directions are opposite, forming a set of action and reaction, thus canceling out the torque generated on A;

[0049] By vertically installing a plurality of reinforcing rods 42 between the two support rods 41, the load-bearing capacity of the support rods 41 can be improved, and no obvious bending deformation will occur, thereby causing the camera cabin 12 to be affected by the torque; for concentrated uniform load q, adding force-bearing rods can share the load pressure, such as the attached Figure 8 As shown, ql = F A +F B ; as attached Figure 8 As shown, two reinforcing rods 42 are installed between the two support rods 41, ql = F A +F B +F C +F D For concentrated loads, adding reinforcing rods 42 can reduce the moment generated between adjacent rods, such as Figure 8 As shown, the support rod 41 is subjected to a concentrated load F, and the moment generated at point AB is As attached Figure 8 As shown, two reinforcing rods 42 are installed between two support rods 41. The support rods 41 are subjected to a concentrated load F, and the moment generated at point CD is Because lCD <l AB Therefore, by installing the reinforcing rod 42 between the two support rods 41, the moment generated by the support rod 41 when subjected to concentrated load becomes smaller, thereby reducing the possibility of deformation.

[0050] Further optimization scheme, a reinforcing ring 122 is provided on the outer wall of the camera cabin body 12, and the reinforcing ring 122 and the inner flange 121 are integrally formed with the camera cabin body 12; the reinforcing ring 122 and the inner flange 121 are located on the same plane; in this embodiment, the camera cabin body 12 is made of titanium alloy material Ti-6A l-4V (TC4), with an outer diameter of 87mm and a wall thickness of 11mm, the inner flange 121 is 8mm wide and 8mm thick, and the reinforcing ring 122 has an axial length of 16mm and a thickness of 15mm;

[0051] The following is a calculation and verification of its compressive strength and deformation optimization. According to the cabin thickness design, the allowable external pressure of the camera cabin 12 is The permissible external pressure of the camera cabin 12 is greater than the maximum pressure of 110 MPa on the seabed, so the camera cabin 12 is suitable for full sea depth pressure environment. The thickened area [p w ] is much greater than the deep sea environment pressure, so the compressive strength of the connection between the inner flange 121 and the reinforcement ring 122 can be ensured. In the deep sea environment of 110Mpa, the radial deformation is The camera cabin 12 is almost not deformed. The meanings of the letters in the formula are as follows:

[0052] p]: Calculate the allowable external pressure

[0053] [p w ]: Maximum working pressure

[0054] D0: camera cabin 12 outer diameter

[0055] D 01 : The outer diameter of the camera cabin 12 after the reinforcement ring is thickened

[0056] δ e :Camera cabin 12 design thickness

[0057] δ1: Design thickness of camera cabin 12 after reinforcing ring thickening

[0058] δ: Design thickness of inner flange 121

[0059] w g : Inner flange 121 design width

[0060] L: calculated length of the camera cabin 12 (the distance between the center lines of adjacent thickened areas)

[0061] [σ] t : Allowable stress at material design temperature

[0062] Δr: radial displacement of the camera cabin 12

[0063] Δr1: Radial variation at inner flange 121

[0064] E: Material elastic modulus

[0065] v: Material Poisson's ratio

[0066] Welding joint coefficient

[0067] With such arrangement, the inner flange 121, the reinforcement ring 122 and the camera cabin 12 are integrally formed to form a support structure that can resist the deformation of the camera cabin 12 caused by the hollow container under the extreme pressure of the deep sea, so that the camera cabin 12 can withstand the high pressure of 110MPa without deformation even at the deepest seabed of 11,000 meters, and the camera movement 13 will not produce an angle change, which effectively ensures the fixation and stability of the relative positions of the two deep-sea camera movements 13, thereby ensuring that the external parameters of the binocular measurement camera do not change with the change of water depth after calibration, thereby ensuring the precision and accuracy of image measurement; because the binocular measurement camera needs to work under different water depths and different pressures in the deep sea, the two deep-sea cameras 1 need to keep the external parameters unchanged under the premise of obtaining a long baseline and having an optical axis angle, that is, the relative posture of the two camera movements 13, including distance and angle, will not change, in order to have a higher measurement accuracy. Especially for binocular vision measurement applied to deep sea, since the pressure of tens to more than one hundred megapascals will be generated at a depth of several thousand to tens of thousands of meters in the deep sea, the hollow metal container or pipe will be deformed by pressure, thereby changing the distance and angle of the two camera movements 13, causing measurement errors. The solution provided by the present invention solves the three problems of compression deformation of the camera cabin, stress deformation of the pressure-resistant fastening components, and torque deformation of the two cameras of the long baseline equipment, and designs a binocular measurement camera structure that is resistant to deep sea high pressure. While obtaining a larger public field of view, it ensures that the deep sea binocular camera will not be affected by the deep sea pressure.

[0068] To further optimize the solution, the angle α is calculated according to the formula Obtained, l represents the baseline length between the two camera movements 13, u represents the object distance between the camera movement 13 and the object to be measured; in this embodiment, the baseline distance of the deep-sea binocular camera is 1m, the observation distance is 1.5m underwater, and the value of the angle α obtained according to the formula is 70.53°.

[0069] A further optimized solution is as follows: the control cabin 2 includes a control cabin body 21, and control cabin end covers 22 are respectively installed at both ends of the control cabin body 21. A control cabin axial hole 221 is opened on the control cabin end cover 22, and one end of the pressure-resistant straight pipe 31 close to the circular flange 33 is plugged into the control cabin axial hole 221, and the circular flange 33 is fixedly connected to the control cabin end cover 22; a control system is installed in the control cabin body 21, and the camera movement 13 is electrically connected to the control system through cables, and the cables are arranged in the pressure-resistant straight pipe 31.

[0070] Further optimizing the scheme, fixing seats 5 are respectively installed on the outer side walls at both ends of the control cabin 2, and the two fixing seats 5 are located between the two control cabin end covers 22; the fixing seats 5 are semicircular sleeve-type fixtures made of electrochemically inert plastic; in this embodiment, the fixing seat 5 includes two semi-fixed plates, the two semi-fixed plates are detachably connected, and semicircular grooves are provided on the opposite end surfaces of the two semi-fixed plates, and the two semi-circular grooves enclose a circular clamping space, and the control cabin 2 is fixed in the circular clamping space;

[0071] In this embodiment, the control system includes electronic devices such as control elements and image analysis processors; the image analysis processor has built-in deep-sea binocular camera measurement software; the internal structure and working principle of electronic devices such as control elements and image analysis processors are all prior art and will not be described in detail here;

[0072] In this arrangement, by installing the fixing seat 5 on the outer wall of the control cabin 2, it is convenient to place the binocular measurement camera on a deep-sea observation platform or a robot and other equipment, so as to carry out a series of positioning and measurement work on the target to be measured.

[0073] To further optimize the scheme, the deep-sea binocular camera measurement software includes a calibration and matching algorithm; in this embodiment, before measuring the deep-sea target image, the binocular camera is first calibrated in shallow water, and the spatial relative position of the two cameras is obtained using chessboard images at multiple angles; in the first step, the two cameras are calibrated as single cameras to obtain the intrinsic parameter matrix K, absolute extrinsic parameters R, T and distortion coefficient d of each camera, and the single camera calibration adopts the classic Zhang Zhengyou calibration method. Then, the relative extrinsic parameters collected each time are calculated, and the median is taken as the initial value; under this scheme, the intrinsic parameters of the camera are fixed values, and the unknowns are the absolute extrinsic parameters (Ri, Ti) of N groups of left cameras and the relative extrinsic parameters R' and T' of 1 group of right cameras relative to the left camera. The minimum reprojection error equation is established, and the absolute extrinsic parameters of the right camera are calculated by the absolute extrinsic parameters and relative extrinsic parameters of the left camera. Finally, based on minimizing the reprojection error, nonlinear iterative optimization obtains the optimal solution.

[0074] Further optimization scheme, deep sea binocular camera measurement software includes a three-dimensional reconstruction algorithm; in this embodiment, the epipolar line correction of the image is first performed. In the ideal case where two image planes are parallel, the direction of the epipolar line is parallel to the scan line of the image. Since the actual stereo vision system does not meet the condition of parallel image planes, the epipolar line correction of the image is equivalent to the image taken under the condition of parallel image planes. In the subsequent feature matching, a one-dimensional epipolar line search can be performed, thereby improving the efficiency of epipolar line matching; then Harris corner points and SIFT feature points with local invariant characteristics are used to extract and match the local features of the image; For the matching of corner points, if there are multiple points to be matched on an epipolar line, other constraints such as boundary constraints are used to remove false matches; for SIFT local feature points, in the initial matching point set determined by the epipolar constraint, if the SIFT local feature point description vectors of two pairs of points are the closest, they are considered to be matching points; on the basis of sparse matching, normalized cross-correlation matching NCC is used for dense matching; based on the matching point set, the three-dimensional model of the deep-sea target organism can be calculated by optical triangulation; after obtaining the three-dimensional model, the distance between any two points can be calculated, thereby realizing the measurement of the deep-sea target organism.

[0075] With this setting, the deep-sea binocular camera measurement software combined with the low-deformation structure design of the deep-sea binocular camera can be calibrated using a chessboard in a pool or shallow sea, and then carried on a platform to measure targets. There is no need to recalibrate at different water depths on the seabed or use high-precision targets for correction, which greatly increases its scope of use.

[0076] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0077] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. For ordinary technical users in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A long baseline deep-sea binocular measurement camera, characterized in that: include: A control cabin (2), the control cabin (2) being used for camera control and storage circuits; Pressure-resistant fastening components (3) are symmetrically installed at both ends of the control cabin (2); A deep-sea camera (1), wherein two of the deep-sea cameras (1) are provided; the two deep-sea cameras (1) are respectively mounted on one end of the two pressure-resistant fastening components (3) away from the control cabin (2); the optical axes of the two deep-sea cameras (1) are located in the same plane, and the angle between the two optical axes is 180°-2α; the two deep-sea cameras (1) are both electrically connected to the control cabin (2); A double-rod support assembly (4), wherein the double-rod support assembly (4) is installed between the two deep-sea cameras (1).

2. The long baseline deep sea binocular measurement camera according to claim 1, characterized in that: The deep-sea camera (1) comprises a camera cabin end cover (11), a camera cabin body (12), a camera movement (13), a pressure-bearing optical lens (15) and a lens cover (14); The camera compartment end cover (11) is cylindrical and one side is cut into a rectangular plane, a camera axis hole (111) is vertically opened on the rectangular plane, the camera axis hole (111) is connected to the interior of the camera compartment body (12), and the angle between the camera axis hole (111) and the central axis of the camera compartment body (12) is α; An inner flange (121) is provided on the inner side wall of the camera cabin (12), and the inner flange (121) is integrally formed with the camera cabin (12); the camera movement (13) is mounted on the inner flange (121); the pressure-bearing optical lens (15) is mounted on a side of the camera cabin (12) away from the camera cabin end cover (11), and the lens cover (14) is mounted on a side of the pressure-bearing optical lens (15) away from the camera cabin end cover (11); the camera cabin end cover (11) is rigidly connected to the pressure-resistant fastening assembly (3); the double-rod support assembly (4) is detachably connected to the camera cabin (12); and both camera movements (13) are electrically connected to the control cabin (2).

3. The long baseline deep sea binocular measurement camera according to claim 2, characterized in that: The pressure-resistant fastening assembly (3) comprises a pressure-resistant straight tube (31), a rectangular flange (32) and a circular flange (33); O-ring grooves (34) are provided at both ends of the pressure-resistant straight tube (31), and O-ring sealing rings are installed in the O-ring grooves (34); the rectangular flange (32) and the circular flange (33) are respectively and vertically fixed to the two ends of the outer wall of the pressure-resistant straight tube (31); one end of the pressure-resistant straight tube (31) is plugged into the camera shaft hole (111), and is fixedly connected to the camera cabin end cover (11) through the rectangular flange (32); the other end of the pressure-resistant straight tube (31) is plugged into the control cabin (2), and is fixedly connected to the control cabin (2) through the circular flange (33).

4. The long baseline deep sea binocular measurement camera according to claim 2, characterized in that: The double-rod support assembly (4) comprises a support rod (41), a reinforcing rod (42) and a bolt (43); two support rods (41) are provided, and a plurality of reinforcing rods (42) and a plurality of bolts (43) are provided; the two camera cabins (12) are installed at both ends of the support rod (41) by means of the bolts (43), and the two support rods (41) are respectively located at the top and bottom of a side of the camera cabin (12) close to the lens cover (14); the reinforcing rod (42) is detachably connected between the two support rods (41) by means of the bolts (43).

5. The long baseline deep sea binocular measurement camera according to claim 2, characterized in that: A reinforcement ring (122) is provided on the outer wall of the camera cabin (12); the reinforcement ring (122) and the inner flange (121) are both integrally formed with the camera cabin (12); and the reinforcement ring (122) and the inner flange (121) are located on the same plane.

6. The long baseline deep sea binocular measurement camera according to claim 2, characterized in that: The angle α is calculated according to the formula Obtained, l represents the baseline length between the two camera movements (13), and u represents the object distance between the camera movement (13) and the object to be measured.

7. The long baseline deep sea binocular measurement camera according to claim 3, characterized in that: The control cabin (2) comprises a control cabin body (21), control cabin end covers (22) are respectively installed at both ends of the control cabin body (21), a control cabin axial hole (221) is opened on the control cabin end cover (22), one end of the pressure-resistant straight pipe (31) close to the circular flange (33) is plugged into the control cabin axial hole (221), and the circular flange (33) is fixedly connected to the control cabin end cover (22); a control system is installed in the control cabin body (21), and the camera movement (13) is electrically connected to the control system via a cable, and the cable is arranged in the pressure-resistant straight pipe (31).

8. The long baseline deep sea binocular measurement camera according to claim 7, characterized in that: A fixing seat (5) is installed on the outer side wall of the control cabin body (21), and the fixing seat (5) is located between the two control cabin end covers (22); the fixing seat (5) is a semicircular sleeve-type fixture processed from electrochemically inert plastic.

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