A special vehicle water attitude testing device and method

Abstract

The application discloses a kind of special vehicle water attitude testing device and method, the method includes: the measuring body of special vehicle front and rear side and the electric signal conversion acquisition control display unit of communication connection with the measuring body, the measuring body includes at least three transparent risers with scale and the communicating vessel of communication each transparent riser, the transparent riser is set on at least three angles of special vehicle front and rear side by mounting bracket, the electric signal conversion acquisition control display unit includes: the magnetic sensitive element of being arranged in each transparent riser, the magnetic sensitive element is equidistant arrangement with the scale of the transparent riser and constitutes magnetic grid position sensor.The advantages of the present application are: can realize automatic acquisition record, also can be observed and read scale data artificial calculation result.Double measurement, improve the accuracy of vehicle water attitude measurement.

Description

Technical Field

[0001] This invention relates to the field of special vehicle technology, specifically to a device and method for testing the attitude of special vehicles in water. Background Technology

[0002] The demand for multi-functional transport vehicles is constantly increasing in today's society. Amphibious vehicles, possessing both the mobility and flexibility of land vehicles and the ability to travel directly on water, have significant strategic importance and have experienced rapid development. Amphibious vehicles, also known as amphibious transport vehicles, are capable of traversing both land and water, possessing broad application value and market prospects, and have attracted considerable attention. For example, in the military field, amphibious vehicles can travel rapidly on roads connecting factories and warehouses or on general land surfaces. When they reach rivers or the sea, they can directly enter the water and maneuver on the water, eliminating the need for docking for the transfer of supplies or personnel. Furthermore, amphibious vehicles can serve as landing craft in wartime, quickly traversing shallow waters to reduce soldier casualties, or in inland waterways. In the civilian sector, amphibious vehicles can rapidly maneuver on muddy and flooded roads during floods; in the tourism industry, amphibious vehicles can be used for both land-based sightseeing and direct waterborne tourism and island hopping.

[0003] The common practice for measuring the attitude of amphibious vehicles in still water involves attaching scales to the four sides of the vehicle (front, rear, left, and right). After the vehicle is submerged, the draft readings on these scales are visually observed, and the vehicle's still-water attitude data is calculated. This method is prone to errors. First, the scales are affected by the vehicle's shape; irregularities in the body or the angle of the sides can introduce measurement errors. Second, when reading data, approaching the vehicle in a small boat creates waves, and visually reading the scales while the water is turbulent introduces subjectivity and cannot yield accurate data. Third, reading data from inside the vehicle is affected by the movement of personnel in different positions, causing changes in the vehicle's center of gravity and introducing errors. Therefore, a convenient and highly accurate attitude measurement device is needed for amphibious vehicle water attitude measurement. Using a gyroscope requires calibrating the zero point on a level surface before launching the vehicle, but finding a standard level surface around the test site is difficult. Summary of the Invention

[0004] This invention proposes a special vehicle water attitude testing device and method, which overcomes or at least partially solves the above-mentioned problems.

[0005] According to one aspect of the present invention, a special vehicle water attitude testing device is provided, characterized in that it comprises: a measuring body installed on the front and rear sides of the special vehicle and an electrical signal conversion, acquisition, control, and display unit communicatively connected to the measuring body. The measuring body includes at least three transparent risers with scales and a connector connecting each of the transparent risers. The transparent risers are mounted on at least three corners of the front and rear sides of the special vehicle via mounting brackets. The electrical signal conversion, acquisition, control, and display unit includes: a magnetic sensitive element disposed within each transparent riser. The magnetic sensitive element is arranged at equal intervals with the scales of the transparent riser to form a magnetic grating position sensor. A magnetic float is placed in the transparent riser and floats on the water surface inside the transparent riser. The position of the float changes with the change of the liquid level inside the riser. The magnetic grating position sensor senses the position of the magnetic float, acquires and calculates data of the pitch and roll angles of the special vehicle for display.

[0006] Furthermore, the mounting bracket includes multiple connecting rods that conform to the shape of the special vehicle and are fixed to each other, with a fixed base for mounting the transparent riser on the connecting rod.

[0007] Furthermore, the connection between the connecting rods is a detachable connection.

[0008] Furthermore, the communicating vessel is a flexible water pipe.

[0009] Furthermore, quick-connect couplings are provided at both ends of the flexible water pipe.

[0010] Furthermore, the magnetic grating position sensor is connected to the central control module / microcontroller via a CAN bus.

[0011] Furthermore, the central control module / microcontroller is connected to the LCD display module.

[0012] According to another aspect of the present invention, a method for testing the water attitude of a special vehicle is provided, characterized in that it includes:

[0013] A measuring body is provided for installation on the front and rear sides of a special vehicle, and an electrical signal conversion, acquisition, control, and display unit is provided for communication with the measuring body. The measuring body includes at least three transparent risers with scales and a connector connecting each of the transparent risers. The transparent risers are installed at at least three corners on the front and rear sides of the special vehicle via a mounting bracket. The electrical signal conversion, acquisition, control, and display unit includes: a magnetic sensitive element installed in each transparent riser. The magnetic sensitive element is arranged at equal intervals with the scales of the transparent riser to form a magnetic grating position sensor. A magnetic float is placed in the transparent riser and floats on the water surface inside the transparent riser. The position of the float changes with the change of the liquid level inside the riser.

[0014] The magnetic grating position sensor detects the position of the magnetic float, acquires and calculates the pitch and roll angle data of the special vehicle for display.

[0015] Furthermore, the acquisition and calculation of the pitch and roll angle data of the special vehicle includes: determining the initial values ​​of the special vehicle parked on a standard plane.

[0016] Furthermore, the acquisition and calculation of the pitch and roll angle data of the special vehicle includes: determining the initial values ​​for parking the special vehicle under unknown slope conditions.

[0017] As can be seen from the technical solution provided by the present invention, the special vehicle water attitude testing device provided by the present invention includes a measuring device body and an electrical signal conversion, acquisition, control, and display unit. The measuring device body includes at least three graduated transparent risers, a mounting base, and a connecting hose connecting these four risers. The electrical signal conversion, acquisition, control, and display unit includes a magnetic grating position sensor, a magnetic float, and a microcontroller acquisition and control board for electrical signal conversion, acquisition, processing, and real-time display. The present invention can achieve automatic acquisition and recording, or the results can be manually calculated by observing and reading the graduated data. Dual measurement improves the accuracy of vehicle water attitude measurement.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0020] Figure 1 This is a schematic diagram of an embodiment of the special vehicle water attitude testing device of the present invention;

[0021] Figure 2 for Figure 1 A schematic diagram of a four-point measurement embodiment of the mounting bracket of the device shown;

[0022] Figure 3 for Figure 1 A schematic diagram of a three-point measurement embodiment of the mounting bracket of the device shown;

[0023] Figure 4 This is a schematic diagram of the internal mounting of the magnetic grating sensor of the present invention;

[0024] Figure 5 This is a schematic diagram of the wall-mounted installation of the magnetic grating sensor of the present invention;

[0025] Figure 6 This is a schematic diagram of an embodiment of the electrical signal conversion, acquisition, control, and display unit of the present invention;

[0026] Figure 7 This is a schematic diagram of the magnetic grating position sensor of the present invention;

[0027] Figure 8 for Figure 1 The system interface relationship diagram of the embodiment shown is illustrated. Detailed Implementation

[0028] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0029] Please refer to Figures 1 to 6 This invention utilizes the principle of equal liquid levels in interconnected containers. Under the influence of gravity, the water levels at different locations will eventually remain consistent. It includes: a measuring body mounted on the front and rear sides of a special vehicle, and an electrical signal conversion, acquisition, control, and display unit communicatively connected to the measuring body. The measuring body includes at least three transparent risers with scales and a connector linking each transparent riser. The transparent risers are mounted on at least three corners of the front and rear sides of the special vehicle via mounting brackets. The electrical signal conversion, acquisition, control, and display unit includes: magnetic sensitive elements disposed within each transparent riser. These magnetic sensitive elements are arranged equidistantly with the scales on the transparent risers to form a magnetic grating position sensor. A magnetic float is placed in each transparent riser, floating on the water surface. The float's position changes with the liquid level within the riser. The magnetic grating position sensor senses the position of the magnetic float, acquires and calculates the pitch and roll angle data of the special vehicle for display.

[0030] The method of converting scale values ​​into electrical signals is as follows: magnetic sensitive elements are arranged at equal intervals with the scale of the riser to form a magnetic grating position sensor. A magnetic float is placed in the riser and floats on the water surface inside the riser. The position of the float changes with the change of the liquid level inside the riser. The MCU is connected to the magnetic sensitive elements to sense the position of the float and calculate the pitch and roll angles of the vehicle body.

[0031] The sensing element of a magnetic grating position sensor is a magnetically sensitive element, which can be a reed switch, a Hall effect chip, or a tunnel magnetoresistive (TMR) sensor. These sensing elements can be arranged in equidistant or unequally spaced gratings. The actual magnetic grating topology is as follows: when an external magnetic object approaches, one or more sensing elements on the grating respond to a magnetic signal, satisfying the following condition in the data-distance domain:

[0032] The relationship between the centroid of Xn-i,...,Xn-2,Xn-1,Xn,Xn+1,Xn+2,...Xn+i and Xn.

[0033] The greatest advantage of this invention is that the distance obtained by the magnetic grating ruler is only related to the location of the magnetic material, and has no relation to the magnetic pole direction, strength, shape, or distance (within the effective distance) of the magnetic material, thus ensuring the stability of distance measurement in various environments.

[0034] Specifically, the measuring riser structure is designed as follows: it includes a communicating vessel, which is mainly composed of flexible water pipes. Quick-connect couplings are used on both sides of the water pipes to connect the front end of the device together, such as... Figure 4 and Figure 5 As shown, the magnetic grating position sensor can be installed inside the measuring riser or attached to the wall outside the measuring riser.

[0035] Specifically, the three magnetic grating position sensors are connected to the built-in microcontroller control module via a CAN bus to process the data collected by the three risers, and the processed position calculation results are displayed on the display.

[0036] In a specific embodiment, four sets of float level sensors are horizontally installed on the front and rear sides of the device under test, with all four sensors remaining horizontal at all times. When the amphibious vehicle enters the water, the magnetic float of each float level sensor floats under the buoyancy of the water. If the device under test tilts to varying degrees in the water, the float will move up and down along the measuring rod. The internal magnet causes the Hall element at the corresponding position within the rod to switch instantaneously, outputting a corresponding position contact signal. This signal is then transmitted via the circuit board through the external interface to the central control module. After single-chip processing, the signal is finally displayed in real-time on the LCD display module, showing the device's attitude in the water.

[0037] In a specific embodiment, alternatively, this device installs three graduated transparent hollow risers at the three corners of the vehicle. The bottom of each riser has a T-junction, and the four hollow risers are interconnected via flexible hoses to form an interconnected container. An appropriate amount of water is injected into the container, ensuring the water level fluctuates within the graduated range. Before measurement, the vehicle is parked on a standard level surface, and the initial graduations of the liquid levels in the three risers are recorded. Then, the vehicle is submerged in water. When the vehicle is level, the graduations of the liquid levels in the three risers are the same as before submersion (relative to the calibration position). When the vehicle is tilted, because the bottoms of the three risers are connected by flexible hoses, the liquid levels in the three risers remain at the same level, and the liquid level changes. By reading the graduations of the liquid levels in the three risers and considering the changes in liquid level and the distance between the risers, the pitch and roll angles of the vehicle can be calculated.

[0038] The present invention provides a method for testing the water attitude of a special vehicle, comprising:

[0039] A measuring body is provided for installation on the front and rear sides of a special vehicle, and an electrical signal conversion, acquisition, control, and display unit is provided for communication with the measuring body. The measuring body includes at least three transparent risers with scales and a connector connecting each of the transparent risers. The transparent risers are installed at at least three corners on the front and rear sides of the special vehicle via a mounting bracket. The electrical signal conversion, acquisition, control, and display unit includes: a magnetic sensitive element installed in each transparent riser. The magnetic sensitive element is arranged at equal intervals with the scales of the transparent riser to form a magnetic grating position sensor. A magnetic float is placed in the transparent riser and floats on the water surface inside the transparent riser. The position of the float changes with the change of the liquid level inside the riser.

[0040] The magnetic grating position sensor detects the position of the magnetic float, acquires and calculates the pitch and roll angle data of the special vehicle for display.

[0041] The following is a detailed description of a method for testing the water attitude of special vehicles provided by this invention. Contents not described in detail in the embodiments of this invention are prior art known to those skilled in the art. Where specific conditions are not specified in the embodiments of this invention, they shall be performed according to conventional conditions in the art or conditions recommended by the manufacturer.

[0042] When a standard level cannot be found before launching the vehicle, park the vehicle stably on a plane with an unknown slope and record the initial water level readings on the three risers. Move the vehicle, turn it around, and then park it back in the original position, this time in the opposite direction, and record the water level readings on the three risers. The midpoint between the two readings is the water level reading on the three risers when the vehicle is parked on a standard level surface.

[0043] To facilitate understanding of the present invention, the relevant parameters involved in the present invention will be briefly described first:

[0044] (1) There are three water jets on the vehicle, labeled A, B, and C.

[0045] (2) Global coordinate system coordinates are represented by letters themselves, such as xy

[0046] (3) In the global coordinate system, the coordinates of the bottom of the water column are denoted as:

[0047] A(x A y A , z A )B(x B y B , z B )C(x c y c , z c )

[0048] (4) Vehicle coordinate system coordinates are represented by letters followed by an apostrophe, such as x′y′

[0049] (5) In the vehicle coordinate system, the coordinates of the bottom of the water column are denoted as:

[0050] A′(x′ A y′ A , z′ A )B′(x′ B y′ B , z′ B )C′(x′ C , y ′ C , z′ C )

[0051] (6) The vehicle roll angle, pitch angle, and heading angle are denoted as α, β, and γ, respectively.

[0052] (7) Convert the vehicle coordinate system to the world coordinate system: (Only the z-coordinate is used below)

[0053]

[0054] First measurement

[0055] (8) Let α=α1, β=β1, γ=γ1

[0056] The water column readings at this time are respectively

[0057] (9) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is:

[0058]

[0059]

[0060]

[0061] (10) Because the water column is tilted, the height of the water column is equal to the reading of the water column multiplied by the cosine of the tilt angle. Therefore, in the world coordinate system, the z-coordinate of the top of the water column is:

[0062]

[0063]

[0064]

[0065] Second measurement

[0066] (11) Let α=α2, β=β2, γ=γ2

[0067] The water column readings at this time are respectively

[0068] (12) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is:

[0069]

[0070]

[0071]

[0072] (13) Therefore, in the global coordinate system, the z-coordinate of the top of the water column is:

[0073]

[0074]

[0075]

[0076] (14) Since the vehicle is pointing in the opposite direction, α2 = -α1, β2 = -β1. Substituting these into the above equation, we get:

[0077]

[0078]

[0079]

[0080] Equality relationship

[0081] (15) The total water volume is equal, denoted as H:

[0082]

[0083]

[0084] (16) In the global coordinate system, the top of the water column is at the same height:

[0085]

[0086]

[0087] Level plane measurement

[0088] (17) Horizontal plane α=β=0

[0089] Let the water column readings at this time be h. A h B h C

[0090] (18) Obviously, physically h A h B h C It is unique. If there is a set of solutions that can satisfy the equations of equality relations (15) and (16), then it must be the water column reading at this time.

[0091] (19) The following proof

[0092]

[0093] Here is a set of solutions.

[0094] (20) Adding the two equations in (15) and dividing by two, we get:

[0095]

[0096] That is to say

[0097] h A +h B +h C =H

[0098] Therefore, this set of solutions satisfies (15).

[0099] (21) Obviously, the z-coordinate of the top of the water column in the global coordinate system is:

[0100] ζ A =h A +z′ A

[0101] ζ B =h B +z′ B

[0102] ζ C =h C +z′ C

[0103] (22)[(10) + (14)] / 2cosα1cosβ1 yields:

[0104]

[0105]

[0106] That is to say

[0107] ζ A =ζ B =ζ C

[0108] Therefore, this set of solutions satisfies equation (16).

[0109] (23) Therefore, this set of solutions is the water column reading when the vehicle is parked on a standard horizontal surface.

[0110] This device features a detachable installation, allowing for easy disassembly after data acquisition. Simple operation enables the determination of a standard horizontal reference, and the riser distance is adjusted according to the vehicle dimensions, maximizing testing accuracy. This device is beneficial for improving both testing efficiency and accuracy.

[0111] It should also be noted that the exemplary embodiments mentioned in this invention describe methods or systems based on a series of steps or apparatus. However, this invention is not limited to the order of the steps described above; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0112] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0113] Similarly, it should be understood that, in order to simplify the invention and aid in understanding one or more of the various inventive aspects, features of the embodiments of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the invention. However, this disclosure should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0114] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0115] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0116] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some or all of the components according to the embodiments of the present invention. The present invention can also be implemented as a device or apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0117] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A special vehicle water attitude testing device, characterized in that, include: A measuring body and an electrical signal conversion, acquisition, control, and display unit are installed on the front and rear sides of a special vehicle. The measuring body includes at least three transparent risers with scales and a connector connecting each transparent riser. The transparent risers are mounted on at least three corners of the front and rear sides of the special vehicle via a mounting bracket. The electrical signal conversion, acquisition, control, and display unit includes a magnetic sensitive element installed inside each transparent riser. The magnetic sensitive element is arranged at equal intervals with the scales of the transparent riser to form a magnetic grating position sensor. A magnetic float is placed in the transparent riser and floats on the water surface inside the transparent riser. The position of the float changes with the change of the liquid level inside the riser. The magnetic grating position sensor senses the position of the magnetic float, acquires and calculates the pitch and roll angle data of the special vehicle for display. (1) There are three water columns on the vehicle, denoted as A, B, and C. (2) Global coordinate system coordinates are represented by the letters themselves, such as xy (3) In the global coordinate system, the coordinates of the bottom of the water column are denoted as: (4) Vehicle coordinates are represented by letters followed by an apostrophe, such as... (5) In the vehicle coordinate system, the coordinates of the bottom of the water column are denoted as: (6) The vehicle roll angle, pitch angle, and heading angle are respectively denoted as... (7) Convert the vehicle coordinate system to the world coordinate system: (Only the z-coordinate is used below) First measurement (8) Let The water column readings at this time are respectively (9) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is: (10) Since the water column is tilted, the height of the water column is equal to the water column reading multiplied by the cosine of the tilt angle; Therefore, in the world coordinate system, the z-coordinate of the top of the water column is: Second measurement (11) Let The water column readings at this time are respectively (12) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is: (13) Therefore, in the global coordinate system, the z-coordinate of the top of the water column is: (14) Because the vehicle is heading in the opposite direction Substituting into the above equation, we get: Equality relationship (15) The total water volume is equal, denoted as H: (16) In the global coordinate system, the top of the water column is at the same height: Level plane measurement (17) Horizontal plane Let the water column readings at this time be respectively (18) Obviously physically It is unique that if there is a set of solutions that can satisfy the equations of equality relations (15) and (16), then it must be the water column reading at this time. (19) The following proof Here is a set of solutions; (20) Adding the two equations in (15) and dividing by two, we get: That is to say Therefore, this set of solutions satisfies (15); (21) Obviously, the z-coordinate of the top of the water column in the global coordinate system is: (twenty two) have to: That is to say Therefore, this set of solutions satisfies equation (16). (23) Therefore, this set of solutions is the water column reading when the vehicle is parked on a standard horizontal surface.

2. The special vehicle water attitude testing device according to claim 1, characterized in that, The mounting frame includes multiple connecting rods that conform to the shape of the special vehicle and are fixed to each other, with a fixed base for mounting the transparent riser on the connecting rod.

3. The special vehicle water attitude testing device according to claim 2, characterized in that, The connection between the connecting rods is a detachable connection.

4. The special vehicle water attitude testing device according to claim 1, characterized in that, The communicating vessel is a flexible water pipe.

5. The special vehicle water attitude testing device according to claim 4, characterized in that, The flexible water pipe is equipped with quick-connect fittings at both ends.

6. The special vehicle water attitude testing device according to claim 1, characterized in that, The magnetic grating position sensor is connected to the central control module / microcontroller via a CAN bus.

7. The special vehicle water attitude testing device according to claim 6, characterized in that, The central control module / microcontroller is connected to the LCD display module.

8. A method for testing the water attitude of special vehicles, characterized in that, include: A measuring body is provided for installation on the front and rear sides of a special vehicle, and an electrical signal conversion, acquisition, control, and display unit is provided for communication with the measuring body. The measuring body includes at least three transparent risers with scales and a connector connecting each of the transparent risers. The transparent risers are installed at at least three corners on the front and rear sides of the special vehicle via a mounting bracket. The electrical signal conversion, acquisition, control, and display unit includes: a magnetic sensitive element installed in each transparent riser. The magnetic sensitive element is arranged at equal intervals with the scales of the transparent riser to form a magnetic grating position sensor. A magnetic float is placed in the transparent riser and floats on the water surface inside the transparent riser. The position of the float changes with the change of the liquid level inside the riser. The magnetic grating position sensor detects the position of the magnetic float, acquires and calculates the pitch and roll angle data of the special vehicle for display. (1) There are three water columns on the vehicle, denoted as A, B, and C. (2) Global coordinate system coordinates are represented by the letters themselves, such as xy (3) In the global coordinate system, the coordinates of the bottom of the water column are denoted as: (4) Vehicle coordinates are represented by letters followed by an apostrophe, such as... (5) In the vehicle coordinate system, the coordinates of the bottom of the water column are denoted as: (6) The vehicle roll angle, pitch angle, and heading angle are respectively denoted as... (7) Convert the vehicle coordinate system to the world coordinate system: (Only the z-coordinate is used below) First measurement (8) Let The water column readings at this time are respectively (9) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is: (10) Since the water column is tilted, the height of the water column is equal to the water column reading multiplied by the cosine of the tilt angle; Therefore, in the world coordinate system, the z-coordinate of the top of the water column is: Second measurement (11) Let The water column readings at this time are respectively (12) According to the equation in (7), the z-coordinate of the bottom of the water column in the global coordinate system is: (13) Therefore, in the global coordinate system, the z-coordinate of the top of the water column is: (14) Because the vehicle is heading in the opposite direction Substituting into the above equation, we get: Equality relationship (15) The total water volume is equal, denoted as H: (16) In the global coordinate system, the top of the water column is at the same height: Level plane measurement (17) Horizontal plane Let the water column readings at this time be respectively (18) Obviously physically It is unique that if there is a set of solutions that can satisfy the equations of equality relations (15) and (16), then it must be the water column reading at this time. (19) The following proof Here is a set of solutions; (20) Adding the two equations in (15) and dividing by two, we get: That is to say Therefore, this set of solutions satisfies (15); (21) Obviously, the z-coordinate of the top of the water column in the global coordinate system is: (twenty two) have to: That is to say Therefore, this set of solutions satisfies equation (16). (23) Therefore, this set of solutions is the water column reading when the vehicle is parked on a standard horizontal surface.

9. The method for testing the water attitude of special vehicles according to claim 8, characterized in that, The process of acquiring and calculating the pitch and roll angle data of the special vehicle includes: determining the initial values ​​for the special vehicle when parked on a standard plane.

10. The method for testing the water attitude of special vehicles according to claim 8, characterized in that, The process of acquiring and calculating the pitch and roll angle data of the special vehicle includes: determining the initial values ​​for parking the special vehicle under unknown slope conditions.

Images