An autonomous underwater vehicle with variable shape and shape changing method

Abstract

An autonomous underwater vehicle with a changeable shape and a method for changing its shape belong to the field of underwater unmanned vehicles. The present invention solves the problem that current autonomous underwater vehicles cannot change their shape according to operational requirements and the fluid environment in which they are located. The present invention divides the outer shell of the autonomous underwater vehicle into two parts: a fixed part and a deformable part. When the autonomous underwater vehicle needs to navigate at high speed, the deformable part is in a first state to ensure that the vehicle has a good fluid shape to reduce fluid resistance; when the autonomous underwater vehicle needs to operate and navigate at low speed, the deformable part is in a second state to ensure that the vehicle has excellent stability. This ensures that the autonomous underwater vehicle has both rapid navigation and operational stability, optimizes navigation performance, and improves the endurance of the autonomous underwater vehicle. The method of the present invention can be applied to the field of underwater unmanned vehicles.

Description

Technical Field

[0001] The present invention belongs to the field of underwater unmanned vehicles, and in particular relates to an autonomous underwater vehicle (AUV) with a changeable shape. Background Art

[0002] The overall shape of an underwater vehicle is the shape of its outermost hull envelope, and its specific shape affects the vehicle's underwater navigation performance. Aircraft can be categorized by their appearance: torpedo-shaped, flat, and irregular.

[0003] Torpedo-shaped designs offer excellent high-speed performance, are insensitive to currents, and provide stable navigation, but are less stable at low speeds. Flat-shaped designs offer good directional stability and strong anti-interference capabilities. Since irregular shapes are often designed for specific operations, their resistance performance is average. Autonomous underwater vehicles (AUVs) often adopt a torpedo-shaped design. While its streamlined shape reduces resistance, it offers poor stability at low, non-cruising speeds. Some AUVs on the market also use a flat-shaped design, which offers better stability in the flat direction and is less susceptible to interference from underwater undercurrents. However, at the same displacement, the resistance is greater, hindering speed and endurance.

[0004] In summary, most autonomous AUVs currently on the market adopt a fixed-form design and are unable to change their appearance according to operational requirements and the fluid environment in which they are located. Their maneuverability, endurance, stability, and speed will be restricted, and the performance potential of the vehicle has not been fully tapped. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that the current autonomous underwater vehicle cannot change its appearance according to the operation requirements and the fluid environment in which it is located, and to propose an autonomous underwater vehicle with a changeable appearance.

[0006] The technical solution adopted by the present invention to solve the above technical problems is:

[0007] According to one aspect of the present invention, an autonomous underwater vehicle with a deformable shape includes a housing, the housing being divided, from the tail to the bow, into a tail section, a second transition section, a main cabin section, a first transition section, and a bow section, the tail section and the bow section forming a fixed portion, and the main cabin section, the first transition section, and the second transition section forming a deformable portion;

[0008] The deformation portion includes a first state and a second state;

[0009] In the first state, the cross-sections of the main compartment are uniformly circular at all locations. The cross-section of the first transition section transitions from the circular cross-section of the main compartment to the elliptical cross-section of the front section. The cross-section of the second transition section transitions from the circular cross-section of the main compartment to the elliptical cross-section of the rear section. The deformable portion in the first state is connected to the fixed portion to form a torpedo-shaped underwater vehicle.

[0010] In the second state, the cross-sections of the main compartment are all elliptical in size. The cross-section of the second transition section transitions from the elliptical cross-section of the main compartment to the elliptical cross-section of the tail section. The cross-section of the first transition section transitions from the elliptical cross-section of the main compartment to the elliptical cross-section of the front section. The deformable portion in the second state is connected to the fixed portion to form a flat underwater vehicle.

[0011] A bulkhead is arranged on the outer side of the shell of the main compartment section. The shell of the main compartment section and the bulkhead constitute a ballast water tank, and a sea port is arranged on the ballast water tank.

[0012] According to another aspect of the present invention, a method for changing the shape of an autonomous underwater vehicle with a changeable shape is provided, wherein the method comprises:

[0013] When the autonomous underwater vehicle needs to transform from a torpedo shape to a flat shape, an electrical signal is used to stimulate the deformable portion of the shell to deform in response, causing the deformable portion to transform from a first state to a second state. During the process of the deformable portion transforming from the first state to the second state, the ballast water tank contracts under the stimulation of the electrical signal and discharges water through the sea port to supplement buoyancy.

[0014] When the autonomous underwater vehicle needs to transform from a flat shape to a torpedo shape, the deformation part of the shell is stimulated by an electrical signal to respond with a deformation, and the deformation part is transformed from the second state to the first state; in the process of the deformation part transforming from the second state to the first state, under the stimulation of the electrical signal, the volume of the ballast water tank gradually increases and absorbs water through the sea outlet to reduce buoyancy.

[0015] The beneficial effects of the present invention are:

[0016] The AUV's fluid profile can be modified based on operational requirements. This can ensure optimal fluid profile during high-speed navigation, reducing fluid resistance. Deformation also allows for excellent stability during operation and low-speed navigation. This allows the AUV to combine rapid navigation with operational stability, optimizing navigation performance and increasing its endurance. Furthermore, the AUV can be used as an underwater mobile platform equipped with various sensors, such as robotic arms and sampling devices, for underwater exploration and operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 Modeling the side view of the autonomous underwater vehicle before deformation;

[0019] Figure 2 Modeling the side view of an autonomous underwater vehicle after deformation;

[0020] Figure 3a It is a longitudinal cross-sectional view of the autonomous underwater vehicle before deformation;

[0021] Figure 3b This is a top-down cross-sectional view of the autonomous underwater vehicle before deformation;

[0022] Figure 3c This is a cross-sectional outline of the shell of the autonomous underwater vehicle before deformation;

[0023] Figure 3d It is a longitudinal sectional view of the autonomous underwater vehicle after deformation;

[0024] Figure 3e This is a top-down cross-sectional view of the autonomous underwater vehicle after deformation;

[0025] Figure 3f The figure is a cross-sectional outline of the shell of the autonomous underwater vehicle after deformation;

[0026] Figure 4 It is a schematic diagram of the appearance curve;

[0027] Figure 5 Schematic diagram of equipment installation beam layout;

[0028] Figure 6 Schematic diagram of the buoyancy adjustment process;

[0029] Figure 7 This is a cross-sectional view of the autonomous underwater vehicle before deformation;

[0030] Figure 8 Schematic diagram of the plug-in device Figure 1 ;

[0031] Figure 9 Schematic diagram of the plug-in device Figure 2 ;

[0032] In the figure, 1 represents the tail section, 2 represents the second transition section, 3 represents the main cabin section, 4 represents the first transition section, 5 represents the head section, 6 represents the bulkhead, 7 represents the ballast water tank, 8 represents the seaport, 9 represents the equipment installation beam, 10 represents the aircraft equipment, 11 represents the supporting component, 12 represents the boss, 13 represents the vertical thruster, 14 represents the lateral thruster, and 15 represents the rudder. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Based on the specific implementation methods of the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] Specific implementation method 1. Combination Figure 1 、 Figure 2 、 Figure 6 and Figure 7 This embodiment describes an autonomous underwater vehicle with a deformable shape, comprising a housing, which is divided, from the tail to the bow, into a tail section 1, a second transition section 2, a main cabin section 3, a first transition section 4, and a bow section 5. The tail section 1 and the bow section 5 constitute a fixed portion, and the main cabin section 3, the first transition section 4, and the second transition section 2 constitute a deformable portion.

[0035] The deformation portion includes a first state and a second state;

[0036] In the first state, the cross-sections of the main compartment 3 at all locations are uniformly circular. The cross-section of the first transition section 4 transitions from the circular cross-section of the main compartment 3 to the elliptical cross-section of the front section 5. The cross-section of the second transition section 2 transitions from the circular cross-section of the main compartment 3 to the elliptical cross-section of the rear section 1. The deformed portion in the first state is connected to the fixed portion to form a torpedo-shaped underwater vehicle.

[0037] In the second state, the cross-sections of the main compartment 3 at all locations are ellipses of uniform size. The cross-section of the second transition section 2 transitions from the elliptical cross-section of the main compartment 3 to the elliptical cross-section of the tail section 1. The cross-section of the first transition section 4 transitions from the elliptical cross-section of the main compartment 3 to the elliptical cross-section of the front section 5. The deformable portion in the second state is connected to the fixed portion to form a flat underwater vehicle.

[0038] A bulkhead 6 is provided on the outer side of the shell of the main compartment section 3 . The shell of the main compartment section 3 and the bulkhead 6 form a ballast water tank 7 , and a sea port 8 is provided on the ballast water tank 7 .

[0039] The shell of the entire AUV from the tail to the bow is: tail section 1, second transition section 2, main cabin section 3, first transition section 4 and bow section 5. The state of the shell before deformation is as follows: Figure 3a 、 Figure 3b 、 Figure 3c As shown, the deformed state is Figure 3d 、 Figure 3e 、 Figure 3f shown. Figure 1 This is a side view of the AUV before deformation. This configuration is the cruising configuration, with the deformed portion in the first state. The cross-sections of the main cabin section 3 are all circular in size, and the cross-section of the first transition section 4 transitions from the circular cross-section of the main cabin section 3 to the elliptical cross-section of the first section 5. Figure 2 This is a side view of the AUV after deformation. This shape is the shape at low speed and hovering, that is, the target shape after deformation. The deformed part is in the second state. The cross-sections of the main cabin section 3 are all elliptical in size. The cross-section of the second transition section 2 transitions from the elliptical cross-section of the main cabin section 3 to the elliptical cross-section of the tail section 1. Figure 2 When the AUV is in a flattened form, the middle main compartment 3 is an elliptical cylinder, and its cross section is an ellipse of uniform size; starting from the two ends of the main compartment 3, the cross-sectional ellipse of the AUV begins to shrink gradually, and the closer it is to the front and rear ends of the AUV, the smaller it becomes until it closes. Figure 1 In the torpedo configuration, the middle main compartment section 3 is cylindrical, i.e., the cross section is a perfect circle of uniform size; Figure 1 The first and last paragraphs in Figure 2 The head and tail sections of the deformed shape are the same, and the cross-section is an ellipse. The closer to the two ends of the AUV, the smaller the ellipse of the cross-section. In the first transition section 4 and the second transition section 2, the cross-section will gradually transition from the perfect circle at both ends of the main cabin section 3 to the ellipse of the head and tail sections.

[0040] The main compartment 3 has bulkheads 6 made of deformable material above and below it. The main compartment's outer shell and pressure bulkhead 6 form a ballast tank 7, with a seaport 8 left in the pressure bulkhead 6. Before deformation, the deformable portion is in a first state, with the ballast tank 7 filled with water, reducing the AUV's actual displacement volume. After deformation, the deformable portion enters a second state, reducing the AUV's volume and causing the ballast tank 7 to contract and drain water to replenish buoyancy. When the outer portion returns to the first state, the AUV expands, and the ballast tank 7 increases in volume and absorbs water, offsetting the excess displacement. The expansion and contraction of the ballast tank can be controlled by a deformation control system, which consists of a microcomputer and cables. The ballast tank deformation control system provides electrical stimulation to cause the tank to expand and contract, controlling the degree of deformation. The volume change of the ballast tank is slightly greater than the maximum volume change caused by deformation. This allows the AUV to increase or decrease buoyancy to achieve ascent or descent while maintaining constant buoyancy. During the whole process, the arc length of the projection of the deformed material bulkhead on the cross section remains unchanged.

[0041] Similar to existing autonomous underwater vehicles, there is a horizontal and a vertical cylindrical through hole at the bow and tail of the vehicle, which runs through the entire vehicle. A vertical thruster 13 is installed in the vertical cylindrical through hole, a lateral thruster 14 is installed in the horizontal cylindrical through hole, and a rudder 15 is installed on the outside of the outer shell of the tail section.

[0042] Specific embodiment 2: This embodiment further limits specific embodiment 1, and the shell is made of an electrical stimulation responsive memory material.

[0043] This embodiment uses an electrically responsive memory material as the material of the shell, so that the shell can deform in response to electrical signal stimulation.

[0044] Specific implementation method three: Combination Figure 5 This embodiment further defines the second embodiment, wherein the autonomous underwater vehicle further comprises an equipment mounting beam 9, the equipment mounting beam 9 passing through the central axis of the autonomous underwater vehicle, and one end of the equipment mounting beam 9 terminates at the junction of the first transition section and the first section, and the other end terminates at the junction of the second transition section and the tail section.

[0045] The equipment mounting beam 9 is provided with a mounting support, which is used to mount the aircraft equipment 10 .

[0046] Small and medium-sized devices can be mounted directly on the support. Larger devices require custom installation or modification, with a central hole cut to allow for installation, or multiple components assembled around a mounting beam. Mounting the device on the mounting beam prevents deformation of the housing and ensures proper operation.

[0047] Specific embodiment 4: This embodiment is a further limitation of specific embodiment 3, and the equipment installation beam 9 is supported by a supporting component 11 .

[0048] In this embodiment, the length of the equipment mounting beam 9 is slightly longer than the sum of the lengths of the main cabin section 3, the first transition section 4 and the second transition section 2. The two ends of the support component 11 are located on one side of the head and tail sections. The support component 11 can be an annular support or a rod.

[0049] Specific implementation method five: Combination Figure 6 、 Figure 7 、 Figure 8 and Figure 9 This embodiment further defines the fourth embodiment. Two ballast water tanks 7 are provided below the main compartment 3. A boss 12 is provided between the two ballast water tanks. The boss 12 is used to dock with an external base, and the external load is mounted on the external base.

[0050] The lower ballast tank is divided into two parts, leaving space for the external base to connect to the AUV through the bottom docking port (boss). External payloads such as sonar, depth gauges, magnetometers, DO sensors, robotic arms, sampling devices, underwater cameras, and other sensors or equipment will be installed on the external base. The center of the boss has an opening that runs through the lower surface of the AUV, allowing the cables of the equipment installed on the external base to connect to the interior of the AUV through the boss. The boss remains sealed and waterproof when the AUV is not equipped with the external base.

[0051] Specific embodiment six: This embodiment further limits the specific embodiment five, and the number of the bosses 12 is three.

[0052] Specific embodiment 7: This embodiment provides a method for changing the shape of an autonomous underwater vehicle with a changeable shape. The method is specifically as follows:

[0053] When the autonomous underwater vehicle needs to transform from a torpedo shape (a shape that is conducive to cruising) to a flat shape (a shape that has excellent stability at low speeds), the deformable portion of the shell is stimulated by an electrical signal to deform in response, and the deformable portion changes from a first state to a second state. During the process of the deformable portion changing from the first state to the second state, under the stimulation of the electrical signal, the ballast tank 7 contracts and discharges water through the sea port 8 to supplement buoyancy.

[0054] When the autonomous underwater vehicle needs to transform from a flat shape to a torpedo shape, the deformation part of the shell is stimulated by an electrical signal to respond with a deformation, and the deformation part is transformed from the second state to the first state; in the process of the deformation part transforming from the second state to the first state, under the stimulation of the electrical signal, the volume of the ballast water tank 7 gradually increases and absorbs water through the sea port 8, thereby offsetting the excess displacement to reduce buoyancy.

[0055] Specific implementation method eight: combination Figure 4 This embodiment is a further limitation of the seventh embodiment. The outer shape curve of the first section 5 is n a =2 Myring-type profile curve:

[0056]

[0057] Where r(x) is the average value of the major and minor semi-axes of the cross section at the point x from the head end of the autonomous underwater vehicle, r max is the radius of the cross-section circle of the main compartment 3, l n is the distance from the head end to the main cabin section 3, l f The length of the first segment 5.

[0058] Specific implementation method nine: combination Figure 4 This embodiment is a further limitation of the eighth embodiment, wherein the outer shape curve r1(x) of the first transition section 4 is:

[0059]

[0060] Where Δr is the difference between the cross-sectional radius of the main compartment section 3 and the average value of the major and minor semi-axes of the cross-sectional radius at the end of the first section 5 (i.e., the junction of the first transition section and the first section), and Δl = l n -l f , Δl is the length of the first transition section 4, f(x) is the transition function;

[0061] f(x)=Ax 3 +Bx 2 +Cx+D

[0062] Among them: A, B, C and D are the coefficients of the transition function;

[0063]

[0064] The above examples are merely illustrative of the calculation model and process of the present invention and are not intended to limit the embodiments of the present invention. Persons skilled in the art will readily appreciate that other variations or modifications based on the above description are possible. This list of embodiments is not exhaustive; however, any obvious variations or modifications derived from the technical solution of the present invention remain within the scope of protection of the present invention.

Claims

1. An autonomous underwater vehicle with a changeable shape, characterized in that: The autonomous underwater vehicle comprises a shell, which is divided into a tail section (1), a second transition section (2), a main cabin section (3), a first transition section (4), and a front section (5) in sequence from the tail to the front, wherein the tail section (1) and the front section (5) constitute a fixed portion, and the main cabin section (3), the first transition section (4), and the second transition section (2) constitute a deformable portion; The deformation portion includes a first state and a second state; In the first state, the cross-sections of the main compartment (3) at all locations are circular in size, the cross-section of the first transition section (4) transitions from the circular cross-section of the main compartment (3) to the elliptical cross-section of the first section (5), and the cross-section of the second transition section (2) transitions from the circular cross-section of the main compartment (3) to the elliptical cross-section of the tail section (1). The deformed portion in the first state is connected to the fixed portion to form a torpedo-shaped underwater vehicle. In the second state, the cross-sections of the main compartment (3) at various locations are ellipses of uniform size, the cross-section of the second transition section (2) transitions from the elliptical cross-section of the main compartment (3) to the elliptical cross-section of the tail section (1), and the cross-section of the first transition section (4) transitions from the elliptical cross-section of the main compartment (3) to the elliptical cross-section of the front section (5). The deformable portion in the second state is connected to the fixed portion to form a flat underwater vehicle. A bulkhead (6) is provided on the outer side of the shell of the main compartment (3); the shell of the main compartment (3) and the bulkhead (6) form a ballast water tank (7); and a sea port (8) is provided on the ballast water tank (7); The autonomous underwater vehicle further comprises an equipment installation beam (9), wherein the equipment installation beam (9) passes through the central axis of the autonomous underwater vehicle, and one end of the equipment installation beam (9) terminates at the junction of the first transition section and the first section, and the other end terminates at the junction of the second transition section and the tail section; The equipment installation beam (9) is provided with an installation support, and the installation support is used to install the aircraft equipment (10).

2. The autonomous underwater vehicle with a changeable shape according to claim 1, characterized in that: The shell is made of an electrical stimulation responsive memory material.

3. The autonomous underwater vehicle with a changeable shape according to claim 2, characterized in that: The equipment installation beam (9) is supported by a supporting member (11).

4. The autonomous underwater vehicle with a changeable shape according to claim 3, characterized in that: Two ballast water tanks (7) are arranged below the main compartment (3), and a boss (12) is arranged between the two ballast water tanks. The boss (12) is used to dock with an external base, and the external load is installed on the external base.

5. The autonomous underwater vehicle with a changeable shape according to claim 4, characterized in that: The number of the bosses (12) is 3.

6. A method for changing the shape of an autonomous underwater vehicle with a changeable shape according to claim 1, characterized in that: The method is specifically as follows: When the autonomous underwater vehicle needs to transform from a torpedo shape to a flat shape, the deformable portion of the shell is stimulated by an electrical signal to respond with a deformation, and the deformable portion is transformed from a first state to a second state; during the process of the deformable portion transforming from the first state to the second state, under the stimulation of the electrical signal, the ballast water tank (7) contracts to discharge water through the sea port (8) to supplement buoyancy; When the autonomous underwater vehicle needs to transform from a flat shape to a torpedo shape, the deformation portion of the shell is stimulated by an electrical signal to respond with a deformation, and the deformation portion is transformed from the second state to the first state; in the process of the deformation portion transforming from the second state to the first state, under the stimulation of the electrical signal, the volume of the ballast water tank (7) gradually increases and absorbs water through the sea port (8) to reduce buoyancy.

7. The method for changing the shape of an autonomous underwater vehicle with a changeable shape according to claim 6, characterized in that: The outline curve of the first section (5) is: Where r(x) is the average value of the major and minor semi-axes of the cross section at the point x from the head end of the autonomous underwater vehicle, r max is the radius of the cross-section circle of the main compartment (3), l n is the distance from the head end to the main compartment (3), l f is the length of the first segment (5).

8. The method for changing the shape of an autonomous underwater vehicle with a changeable shape according to claim 7, characterized in that: The profile curve r1(x) of the first transition section (4) is: Where △r is the difference between the radius of the main compartment section (3) and the average value of the major and minor semi-axes of the section at the end of the first section (5), △l=l n -l f , △l is the length of the first transition section (4), f(x) is the transition function; f(x)=Ax 3 +Bx 2 +Cx+D Among them: A, B, C and D are the coefficients of the transition function;

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