A CCTV-based ship driving line-of-sight compensation method

Abstract

The application discloses a kind of ship driving line of sight compensation methods based on CCTV, and the ideal problem of the problem that the line of sight of ship driving cabin commander is caused by the field of view design of image sensor is shielded is made up, the method includes calculating the angle of obstruction, determining the line of sight compensation range, determining the installation position of image sensor, calculating equivalent line of sight compensation range, selecting appropriate image sensor, cabin video connection configuration and the like steps.The design can effectively solve the problem of the line of sight blind area of cabin caused by the modification of wind power rotor and the like equipment, make up the line of sight range of crew, increase the observation ability to the environment around ship, so as to improve the driving safety of ship, satisfy the requirement of relevant specification rules.

Description

Technical Field

[0001] This invention belongs to the field of ship navigation design technology, specifically relating to a ship navigation line of sight compensation method based on CCTV (Closed Circuit Television). Background Technology

[0002] In order to carry out engineering demonstration and application research on marine wind-powered propulsion rotors, it is necessary to install wind-powered propulsion rotors on larger ship platforms. Since wind-powered propulsion rotors are large deck equipment, the installed wind-powered propulsion rotors are very likely to obstruct the view of the bridge in the existing design where the bridge is located amidships or stern, which will affect the driving safety.

[0003] Taking a 45,000 DWT bulk carrier as the target vessel, an energy-saving retrofit involving the installation of four wind-powered propeller rotors is required. However, after installing these rotors, according to the ISO-provided method for determining line-of-sight, the position 750mm from the forward bulkhead of the bridge is considered the command position. At this position, the rotor's obstruction angle of vision is approximately 5.49°, which does not comply with the China Maritime Safety Administration's "Statutory Inspection Technical Rules for Domestic Navigation Seagoing Vessels," which stipulates that within a 10° range from the bow to any side, each individual blind spot should not exceed 5°. The obstruction of vision from the bridge is shown in the attached figure. Figure 3 As shown, line-of-sight compensation design is required. Summary of the Invention

[0004] To address the above problems, this invention designs a CCTV-based method for compensating for obstructed visibility in ship navigation. This method utilizes a closed-circuit television camera that can avoid obstruction, based on actual ship parameters and wind-powered main rotor installation parameters, to ensure that the design of obstructed visibility in ship navigation meets regulatory requirements.

[0005] This invention discloses a ship navigation line-of-sight compensation method based on CCTV. Through appropriate field-of-sight design of at least one image sensor (CCTV camera), it compensates for the unsatisfactory visibility caused by obstructed vision for the ship's bridge commander. The method is characterized by the following steps:

[0006] S1. Calculate the obstruction angle. Based on the driving command position, the size of the wind-powered booster rotor and the installation position, calculate the obstruction angle of the wind-powered booster rotor according to the ISO (International Organization for Standardization) line-of-sight determination method. The obstruction angle includes the horizontal obstruction angle and the vertical obstruction angle (which can be ignored in the obstruction calculation of this invention).

[0007] S2. Determine the line-of-sight compensation range, which includes the range covering the horizontal obstruction angle;

[0008] S3. Determine the installation location of the image sensor (CCTV camera). The installation location of the image sensor includes the main mast or foremast. Generally, it should be a location on the deck with a good view of the sea surface in the bow direction.

[0009] S4. Calculate the equivalent line-of-sight compensation range. The calculation principle of the equivalent line-of-sight compensation range includes looking from the image sensor installation position towards the direction of line-of-sight occlusion, covering the line-of-sight compensation range (both sides of the bow) described in step S2.

[0010] Let a (in meters) be the horizontal distance from the driver's command position to the image sensor installation position, b be the horizontal distance from the image sensor installation position to the bow, θ be the line-of-sight compensation range, and d be the length of the obstruction boundary from the bow; then the equivalent line-of-sight compensation range φ is...

[0011] φ=2*atan((a+b+d)*tan(θ / 2) / (b+d))

[0012] Where tan() is the tangent function and atan() is the arctangent function;

[0013] S5. Select a suitable image sensor (CCTV camera). The selection principles include that the field of view of the image sensor meets the equivalent line-of-sight compensation range requirements (the horizontal field of view should be at least greater than the equivalent line-of-sight compensation range, and generally should be significantly greater), the viewing distance should not be less than 1000m, and determine the focal length, field of view, and visible range of the CCTV camera. A shorter focal length can provide a wider field of view, but the image may be more blurry, while a longer focal length can provide a farther viewing distance and a clearer image, but the field of view is narrower.

[0014] S6, cab video connection configuration, real-time compensation for obstructed line of sight.

[0015] Furthermore, the image sensor includes a primary image sensor and a backup image sensor. The primary image sensor and the backup image sensor are installed in a vertical structure or a horizontal structure, and their field of view meets the requirements of the equivalent line-of-sight compensation range and the specifications. When installed in a vertical structure, the horizontal field of view coverage of the two image sensors basically overlaps. When installed in a horizontal structure, the overlapping part of the horizontal field of view of the two image sensors is not less than the equivalent line-of-sight compensation range.

[0016] Furthermore, the image sensor includes at least a first image sensor, a second image sensor, and a third image sensor. Three or more image sensors are placed side by side in a horizontal direction. The field of view coverage of two adjacent image sensors is connected or partially overlaps with each other. The field of view of all image sensors is combined to simulate the panoramic field of view of the human eye.

[0017] Furthermore, the image sensor is designed with safety protection features, which include any number of measures such as enhancing the wave resistance of the camera glass (e.g., using thicker tempered glass), adding a stainless steel protective cover (referring to the part excluding the optical axis direction), raising the placement position (in this embodiment, the camera is placed 16.9 meters above the waterline of the structure), and strengthening the equipment base (to improve its corrosion resistance, impact resistance, and vibration resistance).

[0018] Furthermore, the image sensor is designed to be waterproof to prevent water from entering the device and freezing. The waterproof design includes any of the following: the camera is IP68 waterproof, a heating function is added, and a wiper function is provided.

[0019] Furthermore, the image sensor is designed to have night vision functionality to prevent unclear images at night. The night vision functionality includes the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array lamp. The combination of the two can enable an effective detection distance of up to 2000m at night.

[0020] The advantages and beneficial effects of this invention are as follows: The CCTV-based ship navigation visibility compensation method designed in this invention, through the optimized design of installing a CCTV camera on the bow mast as visibility compensation, can effectively solve the problem of blind spots in the bridge caused by wind turbine rotor equipment, compensate for the crew's field of vision, increase the ability to observe the ship's surrounding environment, thereby improving the ship's navigation safety and meeting the requirements of relevant regulations and rules. On the other hand, the design of panoramic and night vision functions can further optimize the navigation visibility effect in the bridge, providing a larger range, farther distance, and more stable viewing effect than manual observation. Simultaneously, it avoids the significant modification costs incurred due to alterations to the hull structure and rotor installation dimensions. This invention has significant reference value for other ships with similar blind spot problems. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a method for compensating for a ship's driver's line of sight based on CCTV.

[0022] Figure 2 This is a side view of the ship's main body after the wind-powered propulsion rotor has been installed;

[0023] Figure 3 This is a diagram showing the obstruction angle (top view) from the driver's position;

[0024] Figure 4 This is a block diagram illustrating the principle of video connection in the driver's cab.

[0025] Marked in the image:

[0026] Image sensor 1, command position 2, wind-powered propulsion rotor 3, bow 4, ship centerline 5, waterline 6;

[0027] First wind-powered rotor (3.1), second wind-powered rotor (3.2), third wind-powered rotor (3.3), fourth wind-powered rotor (3.4);

[0028] The horizontal distance from the driving command position to the image sensor installation position is a (in meters), the horizontal distance from the image sensor installation position to the bow is b, the length of the obstruction boundary defined by the standard is d, and the horizontal length of the extension line connecting the driving position and the bow end extending outward from the bow is e.

[0029] The left and right boundary lines of the shielding angle, when extended, intersect with the shielding boundary defined by the standard from the bow at points A and B, respectively. The line AB is the shielding boundary defined by the standard in the length direction. Detailed Implementation

[0030] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0031] Example 1

[0032] This embodiment uses a 45,000 DWT bulk carrier as the target vessel. Four wind-powered propulsion rotors need to be installed on board. Based on the energy-saving technical requirements, the overall rotor size and layout cannot be modified; only other technical designs can meet the regulatory requirements. According to Article 5, "Equivalent and Alternative Designs," of the "General Provisions" of the China Maritime Safety Administration's "Technical Rules for Statutory Inspection of Domestic Seagoing Ships" (2020), this vessel will adopt an equivalent design for CCTV to compensate for blind spots in the wheelhouse's field of vision, thereby increasing the crew's ability to observe the surrounding environment and improving the ship's navigation safety.

[0033] like Figure 2 Figure 3 As shown, the wind-powered propulsion rotors 3 are arranged along the ship's centerline 5 from bow 4 to stern as follows: first wind-powered propulsion rotor 3.1, second wind-powered propulsion rotor 3.2, third wind-powered propulsion rotor 3.3, and fourth wind-powered propulsion rotor 3.4. The position 750mm from the front bulkhead of the bridge is designated as the driving command position. At this position, the fourth wind-powered propulsion rotor, which is closest to the driving position, has the largest obstruction angle for the line of sight, approximately 5.49°. This does not comply with the requirement of the China Maritime Safety Administration's "Statutory Inspection Technical Rules for Seagoing Ships Navigating Domestically" that within a 10° range from the bow to any side, each individual blind spot should not exceed 5°.

[0034] This invention presents a CCTV-based method for compensating for obstructed vision in ship navigation. Through appropriate field-of-view design of the image sensor 1 (CCTV camera, at least one unit), it compensates for the unsatisfactory visibility caused by obstructed vision for the ship's bridge commander. Figure 1 As shown, it includes the following steps:

[0035] S1. Calculate the occlusion angle, such as Figure 2 and Figure 3 As shown, based on the driving command position 2, the size and installation position of the wind-powered rotor 3, the obstruction angle of the wind-powered rotor is calculated according to the ISO (International Organization for Standardization) line-of-sight determination method. The obstruction angle includes the horizontal obstruction angle and the vertical obstruction angle (which can be ignored in the obstruction calculation of this invention).

[0036] S2. Determine the line-of-sight compensation range, which includes the range covering the horizontal obstruction angle; in this embodiment, the horizontal line-of-sight compensation range is not less than 5.49° (looking from the driver's command position towards the bow); in many cases, in addition to being greater than the obstruction angle requirement, the determination of the line-of-sight compensation range will also take into account the driver's visual habits and leave room for error, and is generally significantly greater than the obstruction angle.

[0037] S3. Determine the installation location of the image sensor (CCTV camera). The image sensor installation location includes the mainmast or foremast, and should generally be located on the deck in a region with good visibility of the sea surface in the bow direction, such as... Figure 2 and Figure 3 As shown, the blind spot in the cockpit of this embodiment is formed by the four rotors on the deck in sequence. If we consider building an area to place the camera in the middle or stern, it will not fundamentally solve the problem of the blind spot. Therefore, to fundamentally solve the problem, it is best to place it in the bow area. At the same time, considering the need to avoid collisions with the bow loading and unloading equipment, it was finally decided to place it on the top of the foremast, and the position of the foremast is the location of the image sensor.

[0038] According to ship design specifications, from the wheelhouse, the sea view should not be obstructed by a distance exceeding twice the ship's length or 500m (whichever is smaller) within a 10° radius from the bow to any side, regardless of draft, trim, or deck cargo position. This example describes a 45,000 DWT bulk carrier. Figure 2 As shown, the horizontal length e of the extension line from the bow of the ship, which is connected to the driving position, is approximately 365m, which is less than twice the ship's length, 380m. However, the length of the image sensor installation position, i.e. the line of sight, which is connected to the bow of the ship through step S3, is much less than e. Therefore, the image sensor installation position selected in this embodiment can meet the specification requirements.

[0039] S4. Calculate the equivalent line-of-sight compensation range. The calculation principle of the equivalent line-of-sight compensation range includes covering the line-of-sight compensation range on both sides of the bow as described in step S2, viewed from the image sensor installation position towards the direction of line-of-sight obstruction. Since the line of sight for ship navigation at sea is generally in the direction of the water surface, i.e., the horizontal direction, there is generally no compensation requirement in the vertical direction. Moreover, the vertical coverage range of the image sensor generally reaches more than 10 degrees, and its equivalent line-of-sight compensation range can be calculated with the horizontal optical axis as the reference. This invention calculates the equivalent line-of-sight compensation range based on the relative relationship between the driving position and the installation position, the direction of the optical axis, and the line-of-sight compensation range. Figure 3 As shown, based on geometric principles, the occlusion angle is directly used as the line-of-sight compensation range. The intersection points of the extended left and right boundary lines of the occlusion angle with the occlusion boundary defined by the standard from the bow are points A and B, respectively (the line AB is the occlusion boundary defined by the standard in the length direction; the boundary length d shown in the figure is not proportional to the lengths a and b). Therefore, the equivalent line-of-sight compensation range of the image sensor installation position is the angle range covered by the lines connecting the installation point to points A and B, respectively.

[0040] In this embodiment, the horizontal distance from the driver's position to the image sensor installation position is 'a' (in meters), the horizontal distance from the image sensor installation position to the bow is 'b', the line-of-sight compensation range is 'θ', and the obstruction boundary length 'd' is defined by the bow. Based on ship specifications and the actual dimensions of the 45000 DWT bulk carrier in this embodiment, the horizontal length e = 365m of the extended line connecting the driver's position and the bow is used as the boundary length 'd' for obstruction calculation (or twice the ship length, 380m, can be considered). Therefore, the equivalent line-of-sight compensation range 'φ' is calculated.

[0041] φ=2*atan((a+b+d)*tan(θ / 2) / (b+d))

[0042] Where tan() is the tangent function and atan() is the arctangent function;

[0043] In this embodiment, the line-of-sight compensation range is taken as the obstruction angle, i.e., θ = 5.49°. Based on the actual ship dimensions a = 155.7m, b = 12.8m, and d = 365m, the calculated equivalent line-of-sight compensation range φ = 7.75°. For clarity, the length d in the diagram is not proportional to a or b; it is only for illustrative purposes. When d = 380m, φ = 7.66°.

[0044] S5. Select a suitable image sensor (CCTV camera). The selection principles include that the field of view of the image sensor meets the equivalent line-of-sight compensation range requirements (the horizontal field of view should be at least greater than the equivalent line-of-sight compensation range, and generally should be significantly greater), the viewing distance should not be less than 1000m, and determine the focal length, field of view, and visible range of the CCTV camera. A shorter focal length can provide a wider field of view, but the image may be more blurry, while a longer focal length can provide a farther viewing distance and a clearer image, but the field of view is narrower.

[0045] This embodiment optimized the focal length and field of view based on the actual conditions during the ship's sea trials to balance the requirements of field of view and image clarity; the final camera parameters are as follows:

[0046] Focal length: 4.8~120mm

[0047] Day / Night Mode: Automatic Switching

[0048] Viewing angle (T telephoto) horizontal: 2.5°~57.6°

[0049] Vertical: 1.4°~34.4°

[0050] Minimum visibility distance: 1m

[0051] Effective visual distance: 2000m

[0052] Focusing modes: Manual / Auto / One-time focus

[0053] To meet the basic requirement that the horizontal field of view must be greater than the equivalent line-of-sight compensation range (7.75°) when adjusting the focal length of the image sensor, this embodiment adjusts the focal length to a medium range, setting the horizontal field of view to 25° and the vertical field of view to approximately 12°. This setting is primarily for medium- to long-distance visibility. Even after the commander makes a small adjustment to the command position, the wind turbine will still create a new obstruction direction within the line-of-sight compensation range of the image sensor, thus not affecting the final visibility effect.

[0054] The optical axis of the image sensor can be oriented horizontally forward or tilted downward appropriately. The tilt angle is generally no more than 5°, depending on the installation height of the image sensor (height above the water surface). The higher the height, the more likely the optical axis should be tilted downward.

[0055] S6, cab video connection configuration, real-time compensation for obstructed line of sight.

[0056] A video monitor is installed near the command position in the driver's cab. Through an image processor and communication module, images from the selected image sensors are displayed in real time for the commander to observe. The connection diagrams of each unit or module are shown below. Figure 4As shown (the markings on the cable connections in the figure indicate the cable number or model); the image processor includes modules such as a hard disk recorder, a power supply unit, an optical fiber box, and an optical fiber transceiver; this embodiment uses image processing algorithms to perform line-of-sight compensation processing on the real-time video signal transmitted by CCTV, repairing images in blind spots and enhancing the brightness, contrast, and sharpness of the image; the signal transmission line uses optical fiber cables to better ensure the stability of signal transmission.

[0057] Preferably, the image sensor is designed with safety protection features, which include any number of measures such as enhancing the wave resistance of the camera glass (e.g., using thicker tempered glass), adding a stainless steel protective cover (referring to the part excluding the optical axis direction), raising the placement position (in this embodiment, the camera is placed 16.9 meters above the structural waterline), and strengthening the equipment base (to improve its corrosion resistance, impact resistance, and vibration resistance). All of the above measures have been designed in this embodiment.

[0058] Preferably, the image sensor is designed to be waterproof to prevent water from entering the device and freezing. The waterproof design includes any of the following: the camera adopts an IP68 waterproof design, an added heating function, and a wiper function. In this embodiment, IP68 waterproof, heating, and wiper functions are designed simultaneously.

[0059] Preferably, the image sensor is designed to have night vision functionality to prevent unclear images at night. The night vision functionality includes the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array lamp. The combination of the two can enable an effective detection distance of up to 2000m at night.

[0060] Because the marine environment is harsh, with salt spray, high temperature, and vibration, it has a significant impact on ship equipment, especially external equipment. Regular maintenance and calibration are necessary, and a risk control measures manual should be compiled. This manual should be used to regularly check the cleanliness of cameras and adjust parameters such as focus and field of view to maintain optimal image quality and line-of-sight compensation (navigation visibility).

[0061] Example 2

[0062] The difference from Embodiment 1 is that the image sensor includes a primary image sensor and a backup image sensor. The primary and backup image sensors are installed either vertically or horizontally, with their field of view meeting the requirements of equivalent line-of-sight compensation and specifications. When installed vertically, the horizontal field of view coverage of the two image sensors essentially overlaps; when installed horizontally, the overlapping portion of the horizontal field of view is not less than the equivalent line-of-sight compensation range. This embodiment adds a backup CCTV system, installed on the foremast in both vertical and horizontal configurations. If one system fails, the other can be used for line-of-sight compensation. The equipment is powered by two separate power supplies: a normal supply and an emergency supply. The equipment cables are protected by steel pipes and placed within the hatch coaming protection area to prevent cable damage. Embodiment 1 only installed one image sensor, which is the primary image sensor.

[0063] Example 3

[0064] The difference from Embodiment 1 is that the image sensor includes at least a first image sensor, a second image sensor, and a third image sensor. Three or more image sensors are placed side by side in the horizontal direction. The field of view coverage of two adjacent image sensors is connected or partially overlaps with each other. The field of view of all image sensors is combined to simulate the panoramic field of view of the human eye.

[0065] The configuration scheme of this embodiment mainly considers that when one of the image sensors can meet the driving equivalent line-of-sight compensation range requirements, by stitching images from multiple image sensors, the stitched field of view is similar to or larger than the field of view observed by the human eye, thereby realizing near-panoramic observation using image sensors; the image stitching technology is a mature technology.

[0066] Because navigation at sea requires continuous monitoring of the port and starboard sides and the front, especially at night, sometimes observation posts need to be set up on the port and starboard sides. On the other hand, the human eye is prone to fatigue after prolonged observation. In reality, the human visual field is sensitive within 10 degrees, 10-20 degrees can correctly identify information, and 20-30 degrees is more sensitive to moving objects. Generally, when the vertical viewing angle of the image is 20 degrees and the horizontal viewing angle is 36 degrees, there will be a very good sense of visual presence. To make up for this by actively moving the person, a larger range of high-quality observation is required.

[0067] Therefore, this embodiment combines line-of-sight compensation and uses image stitching from multiple cameras to achieve a wide-range observation effect for one or more people, enabling homogeneous and fatigue-free observation within a larger field of view.

[0068] Considering that the maximum horizontal field of view for a single human eye is 156 degrees, and the maximum horizontal field of view for both eyes is 188 degrees; the overlapping field of view for both eyes is 124 degrees, which is about one-fifth (25 degrees) when focusing attention, and the comfortable field of view for a single eye is 60 degrees. Therefore, this embodiment configures three image sensors, each with a horizontal field of view of 50 degrees and a vertical field of view of 30 degrees. Adjacent image sensors have a 10-degree overlap in coverage. Thus, the images from the three sensors, when stitched together, form a stable coverage area of ​​130 degrees horizontally and 30 degrees vertically. More image sensors can be configured to create different near-panoramic observation coverage.

[0069] The basic principle of this invention is as follows: by calculating the obstruction angle, determining the line-of-sight compensation range, determining the image sensor installation position, calculating the equivalent line-of-sight compensation range, selecting a suitable image sensor, and configuring the bridge video connection, the field of view of the image sensor is designed to compensate for the problem of unsatisfactory visibility caused by line-of-sight obstruction for the bridge commander. This design can effectively solve the problem of blind spots in the bridge caused by the modification of equipment such as wind turbine rotors, compensate for the line-of-sight range physically obstructed by the bridge commander, increase the ability to observe the surrounding environment of the ship, thereby improving the ship's navigation safety and meeting the requirements of relevant regulations and rules.

[0070] The above descriptions are merely some relatively systematic and comprehensive embodiments of the CCTV-based ship navigation line-of-sight compensation method of the present invention. In fact, the image sensor configuration can be optimized according to the preferred scheme (such as setting more image sensors), and the image sensor can be selectively designed for safety protection, waterproofing, night vision function, etc. These combinations should also be considered within the scope of protection of the present invention, and will not be listed one by one here.

Claims

1. A CCTV-based ship steering line-of-sight compensation method, characterized by, Includes the following steps: S1. Calculate the obstruction angle: Based on the size and installation position of the driver command position (2) and the wind-powered booster rotor (3), calculate the obstruction angle of the wind-powered booster rotor to the driver command position according to the ISO line of sight determination method. The obstruction angle includes the horizontal obstruction angle. S2. Determine the line-of-sight compensation range: The line-of-sight compensation range covers the range of the horizontal obstruction angle; S3. Determine the image sensor installation location: The image sensor installation location includes the main mast or the foremast; S4. Calculate the equivalent line-of-sight compensation range: The calculation principle of the equivalent line-of-sight compensation range includes looking from the installation position of the image sensor towards the direction of line-of-sight occlusion, covering the line-of-sight compensation range described in step S2. Let a be the horizontal distance from the driver's command position to the image sensor mounting position, b be the horizontal distance from the image sensor mounting position to the bow, θ be the line-of-sight compensation range, d be the length of the obstruction boundary defined by the bow, and φ be the equivalent line-of-sight compensation range. φ=2*atan((a+b+d)*tan(θ / 2) / (b+d)) Where tan() is the tangent function and atan() is the arctangent function; S5. Select image sensor: The horizontal field of view of the image sensor is greater than the equivalent line-of-sight compensation range; S6. Install and configure the image sensor: Install the image sensor at the location determined in step S3, and transmit its video signal in real time to the video monitor configured near the driver's cab command position to compensate for the obstructed line of sight.

2. The method of claim 1, wherein, The image sensor includes a primary image sensor and a backup image sensor, which are mounted vertically or horizontally.

3. The method of claim 1, wherein, The image sensor includes at least a first image sensor, a second image sensor, and a third image sensor. The image sensors are placed side by side in a horizontal direction. The field of view coverage of two adjacent image sensors is connected or partially overlaps with each other. The field of view of all image sensors is combined to simulate the panoramic field of view of the human eye.

4. A CCTV-based ship's eye-sight line compensation method according to any one of claims 1 to 3, characterized in that, The image sensor is designed with safety protection measures, which include at least one of the following: enhancing the wave resistance of the camera glass, adding a stainless steel protective cover, raising the placement position, and strengthening the corrosion resistance, impact resistance, and vibration resistance of the equipment base.

5. A CCTV-based ship's eye-sight line compensation method according to any one of claims 1 to 3, characterized in that, The image sensor is designed to be waterproof, and the waterproof design includes at least one of the following: the camera is designed to be IP68 waterproof, a heating function is added, and a wiper function is provided.

6. A method for compensating for ship navigation visibility based on CCTV according to claim 4, characterized in that, The image sensor is designed to be waterproof, and the waterproof design includes at least one of the following: the camera is designed to be IP68 waterproof, a heating function is added, and a wiper function is provided.

7. A method for compensating for ship navigation visibility based on CCTV according to any one of claims 1 to 3, characterized in that, The image sensor is designed to have night vision capabilities, which include the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array.

8. A method for compensating for ship navigation visibility based on CCTV according to claim 4, characterized in that, The image sensor is designed to have night vision capabilities, which include the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array.

9. A method for compensating for ship navigation visibility based on CCTV according to claim 5, characterized in that, The image sensor is designed to have night vision capabilities, which include the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array.

10. A method for compensating for ship driving visibility based on CCTV according to claim 6, characterized in that, The image sensor is designed to have night vision capabilities, which include the use of a high-sensitivity infrared sensor and / or a high-efficiency white light array.

Images