Calculation method for sight blind area of ship cab

Abstract

The invention discloses a ship cab sight blind area calculation method. The ship cab sight blind area calculation method specifically comprises the following steps of S1, selecting an obstacle which shields sight; s2, determining an obstacle horizontal section S of the obstacle at the sight height of the driver; s3, determining a center point P of head rotation when the driver observes the obstacle in the plane where the eyes of the driver are located; s4, respectively selecting a point on the left eye and the right eye of the driver, respectively defining the points as a point E1 and a point E2, and connecting the point E1 with the point E2; s5, calculating the blind area angle of the cross section of the obstacle S based on the point E1, the point E2 and the point P; s6, blind area angles of all obstacles in the required view range are calculated through the calculation method, and finally superposition is carried out to obtain the total blind area range. According to the method for calculating the sight blind area of the ship cab, the concept of double eyes is introduced, traditional points are replaced by the pupil distance, and the actual sight blind area is simulated more accurately.

Description

Technical Field

[0001] The invention relates to the technical field of shipbuilding, and in particular to a method for calculating a blind area of ​​vision in a ship's cab. Background Art

[0002] According to the annex to Resolution A.708 (17) of the International Maritime Organization (IMO), it is required that within the horizontal range of 180 degrees directly in front of the command position in the ship's wheelhouse, the single line of sight blind area shall not exceed 10 degrees, and the total line of sight blind area shall not exceed 20 degrees. The content of the second article of Section 3 of Chapter 6 of the Norwegian Classification Society (DNV) Rules stipulates that for ships with a one-man bridge class symbol, the horizontal line of sight of the driving, operating and monitoring positions shall not be less than 225 degrees, and the total line of sight blind area shall not exceed 30 degrees. In the ISO8468:2007 standard, the driving and operating working positions are required to meet the 225-degree field of view, and the total blind area shall not exceed 20 degrees. In order to meet the requirements of relevant laws, regulations and standards, it is necessary to calculate and verify the blind area of ​​the wheelhouse during the ship design stage.

[0003] The current method for calculating the blind spot of the cab is to approximate the eye as a point and measure the size of the blind spot through the tangent formed by the point and the outer edge structure of the structure that blocks the line of sight. The combined field of vision of the eyes exceeds the field of vision measured with a single point as the center. The current calculation method cannot accurately reflect the actual blind spot of vision, which will lead to an overestimation of the actual size of the blind spot, resulting in an increase in shipbuilding costs and waste in actual operations. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for calculating the blind spot of the ship's cab, which more accurately simulates the actual blind spot by introducing the concept of binoculars and replacing the traditional point with the pupil distance.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions: A method for calculating the blind area of ​​a ship's cab vision comprises the following steps: S1. Select an obstacle that blocks the view; S2. Determine the horizontal cross section S of the obstacle at the driver's sight height; S3. Determine the center point P of the driver's head rotation when observing obstacles in the plane where his eyes are located; S4. Select a point on the left and right eyes of the driver, respectively, defined as point E1 and point E2, and connect point E1 and point E2; S5. If the obstacle is located on the port side of the ship, rotate the line connecting point E1 and point E2 around point P so that the tangent line from point E1 to the left side of the S section is at right angles to the line connecting point E1 and point E2. Draw a tangent line from point E1 to the left side of the S section and a tangent line from point E2 to the right side of the S section. Draw a line parallel to the former tangent line from point E2. The plane angle formed by the latter tangent line is the blind spot angle of the obstacle S section. If the obstacle is located on the starboard side of the ship, the line connecting point E1 and point E2 rotates around point P so that the tangent from point E2 to the right side of section S2 forms a right angle with the line connecting point E1 and point E2. A tangent is drawn from point E2 to the right side of section S and from point E1 to the left side of section S. A line parallel to the former tangent is drawn from point E1. The plane angle formed by the latter tangent is the blind spot angle of section S of the obstacle. S6. All obstacles within the field of view are required to be calculated using the above calculation method to calculate the blind spot angles respectively, and finally superimposed to obtain the total blind spot range.

[0006] Furthermore, the S2 specifically includes the following steps: S21. Determine the center position V of the driver's head at his / her sight height; S22. Determine the horizontal plane where point V is located, and use the intersection of the horizontal plane and the selected obstacle as the obstacle cross section S calculated for the obstacle blind spot.

[0007] Further, in S4, the point E1 and the point E2 are the pupil point of the driver's left eye and the pupil point of the driver's right eye, respectively.

[0008] Furthermore, the distance between the line connecting point E1 and point E2 and point P is 99 mm.

[0009] Furthermore, the obstacles include all cab structures that block the view within a 112.5° viewing angle on both sides of the horizontal direction when the driver is in the driving seat.

[0010] Furthermore, when calculating the blind spot of the wheelhouse during the ship design stage, the distance between the centers of the two pupils of the driver is set to 60 mm.

[0011] Furthermore, the height of the head center position V point from the cab deck is 1500mm, and the horizontal and vertical distance between the head center position V point and the control console is 350mm.

[0012] The method for calculating the blind spot of the ship's cab vision of the present invention introduces the concept of binoculars, replacing the previous single-point calculation method, and can effectively reduce the value of the blind spot. The concept of binoculars is closer to the normal use conditions of the human body and has been recognized by ship inspections in actual ship projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1This is an example of the method for calculating the blind spot of the ship's cab according to the present invention.

[0014] Figure 2 This is a schematic diagram of determining the V point of the present invention.

[0015] Figure 3 It is a schematic diagram of the horizontal sight line range described in the present invention.

[0016] Figure 4 This is a schematic diagram of the positional relationship between point P and the connecting lines between points E1 and E2 according to the present invention.

[0017] Figure 5 This is an example of the existing method for calculating the blind spot of the ship's cab. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. 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.

[0019] The blind spot is the area at the driver's seat that is blocked by the structure between the windows of the cab and cannot be directly observed.

[0020] like Figure 1~Figure 4 As shown, a method for calculating the blind area of ​​the ship's cab vision includes the following steps: S1. Select an obstacle that blocks the view; S2. Determine the horizontal cross section S of the obstacle at the driver's sight height; S3. Determine the center point P of the driver's head rotation when observing obstacles in the plane where his eyes are located; S4. Select a point on the left and right eyes of the driver, respectively, defined as point E1 and point E2, and connect point E1 and point E2; S5. If the obstacle is located on the port side of the ship, rotate the line connecting point E1 and point E2 around point P so that the tangent line from point E1 to the left side of the S section is at right angles to the line connecting point E1 and point E2. Draw a tangent line from point E1 to the left side of the S section and a tangent line from point E2 to the right side of the S section. Draw a line parallel to the former tangent line from point E2. The plane angle formed by the latter tangent line is the blind spot angle of the obstacle S section. If the obstacle is located on the starboard side of the ship, the line connecting point E1 and point E2 rotates around point P so that the tangent from point E2 to the right side of section S2 forms a right angle with the line connecting point E1 and point E2. A tangent is drawn from point E2 to the right side of section S and from point E1 to the left side of section S. A line parallel to the former tangent is drawn from point E1. The plane angle formed by the latter tangent is the blind spot angle of section S of the obstacle. S6. All obstacles within the field of view are required to be calculated using the above calculation method to calculate the blind spot angles respectively, and finally superimposed to obtain the total blind spot range.

[0021] In this embodiment, S2 specifically includes the following steps: S21. Determine the center position V of the driver's head at the height of his line of sight; in this embodiment, the height of the center position V of the head from the cab deck is 1500mm, and the horizontal and vertical distance between the control console and the control console is 350mm; S22. Determine the horizontal plane where point V is located, and use the intersection of the horizontal plane and the selected obstacle as the obstacle cross section S calculated for the obstacle blind spot.

[0022] In this embodiment, in S4, the point E1 and the point E2 are the pupil points of the driver's left eye and right eye respectively; when calculating the blind spot of the cab during the ship design stage, the distance between the centers of the two pupils of the driver is set to 60 mm; the distance between the line connecting the point E1 and the point E2 and the point P is 99 mm.

[0023] It can be understood that selecting point E1 and point E2 as the driver's left eye pupil point and right eye pupil point respectively can make the tangent line between the driver's line of sight and the obstacle cross section more precise and the calculation of the blind spot angle more accurate.

[0024] In this embodiment, the obstacles include all cab structures that block the view within a 112.5° viewing range on both sides of the horizontal direction when the driver is in the driving seat.

[0025] The calculation method of the present invention is used to calculate the blind area of ​​the cab, and according to the calculation result, the design of the cab is optimized to reduce the blind area. The method of the present invention takes into account the diversity of human physiological characteristics, so that the calculation of the blind area is more accurate. The method can be applied to the ship design stage to provide a scientific basis for the layout and construction of the cab.

[0026] The cab structure includes Although embodiments of the present invention have been shown and described, it is understandable to those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the blind spot of a ship's cab, characterized in that: The specific steps include: S1. Select an obstacle that blocks the view; S2. Determine the horizontal cross section S of the obstacle at the driver's sight height; S3. Determine the center point P of the driver's head rotation when observing obstacles in the plane where his eyes are located; S4. Select a point on the left and right eyes of the driver, respectively, defined as point E1 and point E2, and connect point E1 and point E2; S5. If the obstacle is located on the port side of the ship, rotate the line connecting point E1 and point E2 around point P so that the tangent line from point E1 to the left side of the S section is at right angles to the line connecting point E1 and point E2. Draw a tangent line from point E1 to the left side of the S section and a tangent line from point E2 to the right side of the S section. Draw a line parallel to the former tangent line from point E2. The plane angle formed by the latter tangent line is the blind spot angle of the obstacle S section. If the obstacle is located on the starboard side of the ship, the line connecting point E1 and point E2 rotates around point P so that the tangent from point E2 to the right side of section S2 forms a right angle with the line connecting point E1 and point E2. A tangent is drawn from point E2 to the right side of section S and from point E1 to the left side of section S. A line parallel to the former tangent is drawn from point E1. The plane angle formed by the latter tangent is the blind spot angle of section S of the obstacle. S6. All obstacles within the field of view are required to be calculated using the above calculation method to calculate the blind spot angles respectively, and finally superimposed to obtain the total blind spot range.

2. The method for calculating the blind spot of the ship's cab according to claim 1 is characterized in that: The S2 specifically includes the following steps: S21. Determine the center position V of the driver's head at his / her sight height; S22. Determine the horizontal plane where point V is located, and use the intersection of the horizontal plane and the selected obstacle as the obstacle cross section S calculated for the obstacle blind spot.

3. The method for calculating the blind spot of the ship's cab according to claim 2 is characterized in that: In S4, the point E1 and the point E2 are the pupil point of the driver's left eye and the pupil point of the driver's right eye respectively.

4. The method for calculating the blind spot of the ship's cab according to claim 3 is characterized in that: The distance between the line connecting point E1 and point E2 and point P is 99 mm.

5. The method for calculating the blind area of ​​the ship's cab according to claim 4 is characterized in that: The obstacles include all cab structures that block the view within a 112.5° view range on both sides of the horizontal direction when the driver is in the driving seat.

6. The method for calculating the blind spot of the ship's cab according to claim 5 is characterized in that: When calculating the blind spot of the wheelhouse during the ship design stage, the distance between the centers of the driver's two pupils is set to 60 mm.

7. The method for calculating the blind area of ​​the ship's cab according to claim 6 is characterized in that: The height of the head center point V from the cab deck is 1500mm, and the horizontal and vertical distance between the head center point and the control console is 350mm.

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