An underwater robot

Abstract

The invention discloses an underwater robot, which belongs to the technical field of marine detection equipment. The whole machine frame is a rectangular frame structure, including a top frame, a bottom frame and a vertical frame; the cabin is arranged on the bottom frame, and the cabin is extended along the length direction of the bottom frame; the rectangular floating body is arranged on the top frame, and the positions near the four corners of the floating body are respectively provided with propulsion ducts that pass through from top to bottom, and the four propulsion ducts are symmetrically arranged around the center of the floating body, and each propulsion duct extends obliquely from bottom to top toward the center of the floating body; a first propeller is arranged in the propulsion duct; a second propeller is arranged on the vertical frame, and the four second propellers are symmetrically arranged, and the second propellers are arranged in the horizontal direction and obliquely arranged relative to the length direction of the frame; the mechanical arm is arranged on the width side of the bottom frame. The underwater robot can realize multi-degree-of-freedom precise hovering under the disturbance of the external environment, and the movement is flexible, and the operation efficiency of the end of the mechanical arm is high.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean detection equipment, and in particular to an underwater robot. Background Art

[0002] Underwater robots are one of the most widely used marine exploration equipment. They can perform flexible operations in complex environments and narrow waters, such as seabed mapping, mineral exploration, environmental monitoring, etc. However, underwater robots with a single function cannot achieve more complex underwater tasks, such as grabbing certain objects. Therefore, it is necessary to equip the underwater robot with corresponding actuators, that is, robotic arms. This combination is called an underwater vehicle manipulator system (UVMS).

[0003] At present, there is a large development gap in the body structure design and modeling control methods of underwater robots. The motion control performance of the underwater robot manipulator system is still lacking. It is difficult to achieve precise hovering under the disturbance of the external environment, which affects the operating efficiency and control accuracy of the manipulator.

[0004] The above information disclosed in this background technology is only used to increase the understanding of the background technology of this application, and therefore, it may include information that does not constitute the prior art known to ordinary technicians in this field. Summary of the invention

[0005] In view of the problems pointed out in the background technology, the present invention proposes an underwater robot, which can realize precise hovering with multiple degrees of freedom under the disturbance of the external environment, has flexible movement and high operating efficiency at the end of the robotic arm.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] In some embodiments, an underwater robot is provided, comprising:

[0008] A frame, which is a rectangular frame structure, including a top frame, a bottom frame, and a vertical frame arranged between the top frame and the bottom frame, wherein the vertical frame is located at four corners of the rectangular frame structure;

[0009] A cabin body, which is arranged on the bottom frame, and the cabin body is extended along the length direction of the bottom frame;

[0010] A floating body, which is arranged on the top frame, and the floating body is a rectangular structure. The floating body is provided with propulsion ducts passing through from top to bottom at positions near the four corners thereof. The top opening of the propulsion duct is a water inlet, and the bottom opening of the propulsion duct is a water outlet. The four propulsion ducts are symmetrically arranged around the center of the floating body, and each of the propulsion ducts extends obliquely from bottom to top toward the center of the floating body;

[0011] four first propellers, each of the propulsion ducts being provided with one of the first propellers;

[0012] Four second propellers, each of the vertical frames is provided with one second propeller, the four second propellers are symmetrically arranged, the second propellers are arranged in a horizontal direction and are inclined relative to the length extension direction of the frame;

[0013] The mechanical arm is arranged on the width side of the bottom frame.

[0014] In some embodiments, the thickness of the float is smaller than the length and width of the float, the width of the float is equal to the width of the top frame, and the length of the float is equal to the length of the top frame.

[0015] In some embodiments, a mounting groove is provided in the buoy, a sonar is provided in the mounting groove, and a top of the sonar is exposed from the mounting groove.

[0016] In some embodiments, the second propeller is disposed on the inner side of the vertical frame.

[0017] In some embodiments, a lighting device and a camera device are provided on the vertical frame, and the lighting device, the camera device and the mechanical arm are located on the same side of the frame.

[0018] In some embodiments, the bottom frame is provided with a plurality of mounting frames spaced apart along its length direction, the mounting frames having a placement slot with an open top, the cabin body is disposed in the placement slot, and the cabin body is confined in the placement slot by a strap.

[0019] In some embodiments, the mounting frame spans the width direction of the bottom frame, and a plurality of the placement slots are provided on the mounting frame;

[0020] There are a plurality of cabins, and the plurality of cabins are arranged in one-to-one correspondence with the plurality of placement slots.

[0021] In some embodiments, counterweights are respectively provided at the four bottom corners of the bottom frame.

[0022] Compared with the prior art, the advantages and positive effects of the present invention are:

[0023] The underwater robot disclosed in this application has a 6-degree-of-freedom motion control capability, and its float and thruster configuration is generated based on structural stability parameters and computational fluid dynamics analysis results. The vector combination arrangement of 8 thrusters (including 4 first thrusters and 4 second thrusters) enables the robot to generate 6-degree-of-freedom motion control capabilities regardless of hovering or moving. The vertical thruster duct direction design meets the requirements of heave, pitch, and roll multi-degree-of-freedom hovering control. The horizontal thruster direction design meets the requirements of sway, sway, and bow multi-degree-of-freedom motion control.

[0024] The appearance design of the underwater robot reduces water resistance and improves the accuracy of parameter calculation. It provides ducts for the four first thrusters in a limited space, thereby improving the efficiency of energy conversion when the thrusters push water. The ducts use a standard cylindrical through-hole shape, which also improves the accuracy of thrust parameter calculation and analysis.

[0025] The inclined arrangement of the four first thrusters on the top can produce a four-thrust vector superposition effect, which can generate large thrust in the roll, pitch and heave directions. This arrangement makes the robot's posture extremely flexible.

[0026] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 is a schematic structural diagram of an underwater robot according to an embodiment;

[0029] Figure 2 for Figure 1 The structure shown is a schematic diagram of the structure after the connection lines are omitted;

[0030] Figure 3 for Figure 2 The structure shown is a schematic diagram of the structure after the cabin is omitted;

[0031] Figure 4 is a schematic structural diagram of a framework according to an embodiment;

[0032] Figure 5 is a schematic structural diagram of a floating body and four first thrusters according to an embodiment;

[0033] Figure 6is a schematic structural diagram of a floating body according to an embodiment;

[0034] Figure 7 for Figure 6 Middle AA section view;

[0035] Figure 8 is a simplified schematic diagram of two propulsion ducts viewed from the front side of the floating body according to an embodiment;

[0036] Fig. 9 is a simplified schematic diagram of two propulsion ducts viewed from above the floating body according to an embodiment;

[0037] Fig.10 is a schematic top view of the layout of four second thrusters according to an embodiment;

[0038] Fig.11 A schematic diagram of a generalized object of an underwater robot in a robust controller design process according to an embodiment;

[0039] Fig.12 is a bow rolling model parameter table according to an embodiment;

[0040] Fig.13 is a step response diagram of a nominal continuous system of an underwater robot according to an embodiment;

[0041] Fig.14 is a diagram showing outputs of a nominal continuous system controller of an underwater robot according to an embodiment;

[0042] Fig.15 is a step response diagram of a continuous system under the action of uncertain factors of an underwater robot according to an embodiment;

[0043] Fig.16 is an output diagram of a continuous system controller under the influence of uncertain factors of an underwater robot according to an embodiment;

[0044] Fig.17 is a step response performance index parameter table according to an embodiment;

[0045] Reference numerals:

[0046] 100-frame, 110-top frame, 120-bottom frame, 130-vertical frame, 140-mounting frame, 141-placing slot, 150-binding strap;

[0047] 200- floating body, 210- propulsion duct, 220- installation slot;

[0048] 300 - first thruster;

[0049] 400 - second thruster;

[0050] 500-cabin;

[0051] 600-Robotic arm;

[0052] 710- sonar, 720- lighting device, 730- camera device, 740- counterweight. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0055] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0056] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0058] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0059] In some embodiments, an underwater robot is provided, referring to Figures 1 to 3 ,in Figure 2 The relevant connection lines are omitted. Figure 3 The cabin is further omitted to illustrate the main components in a concise and clear manner. The underwater robot includes a frame 100, a cabin 500, a floating body 200, a first propeller 300, a second propeller 400, and a mechanical arm 600.

[0060] In some embodiments, the structure of the frame 100 is referred to as Figure 4 The frame 100 is a rectangular frame structure composed of a plurality of pipes, including a top frame 110, a bottom frame 120, and a vertical frame 130 disposed between the top frame 110 and the bottom frame 120. The vertical frame 130 is located at the four corners of the rectangular frame structure. Both the top frame 110 and the bottom frame 120 are rectangular structures.

[0061] In some embodiments, the structure of the floating body 200 is as shown in FIG. Figures 5 to 7 The floating body 200 is a flat rectangular structure, and the floating body 200 is fixed on the top of the top frame 110.

[0062] In some embodiments, propulsion ducts 210 are respectively provided near the four corners of the floating body 200, the top opening of the propulsion duct 210 is a water inlet, the bottom opening of the propulsion duct 210 is a water outlet, and the four propulsion ducts 210 are symmetrically arranged around the center of the floating body 200, and each propulsion duct 210 extends obliquely from bottom to top toward the center of the floating body 200. The direction design of the propulsion duct 210 meets the requirements of heave, pitch, and roll multi-degree-of-freedom hovering control.

[0063] In some embodiments, four first propellers 300 are provided, and one first propeller 300 is provided in each propulsion duct 210 .

[0064] In some embodiments, four second propellers 400 are also provided, and each vertical frame 130 is provided with a second propeller 400. Fig.10 The four second thrusters 400 are arranged symmetrically, and the second thrusters 400 are arranged in the horizontal direction and tilted relative to the length extension direction of the frame 100. The four second thrusters 400 form a vector layout. The direction design of the second thrusters 400 meets the multi-degree-of-freedom motion control requirements of surge, sway, and pitch.

[0065] In some embodiments, a mechanical arm 600 is provided on the width side of the bottom frame 120, and the mechanical arm 600 is located at one end of the entire frame 100, and this end is defined as the front end of the underwater robot. The mechanical arm 600 does not interfere with the robot body during movement.

[0066] In some embodiments, regarding the setting of the float 200, the flat float 200 is located on the top of the entire underwater robot, wrapping the four first thrusters 300 on the top, so that the center of buoyancy of the entire system is higher and the center of gravity is lower. The entire system has a weak positive buoyancy, thereby improving the overall hydrodynamic performance of the underwater robot.

[0067] The thickness of the floating body 200 is smaller than the length and width of the floating body 200 . The floating body 200 is a flat rectangular structure. The width of the floating body 200 is equal to the width of the top frame 110 , and the length of the floating body 200 is equal to the length of the top frame 110 .

[0068] The flattened rectangular design of the float 200 is more friendly to the numerical calculation of the hydrodynamics of the underwater robot, and its numerical calculation results will be more accurate, which is helpful to establish an accurate hydrodynamic model.

[0069] In addition, since the height of the entire floating body 200 is relatively small, its rotational damping is relatively small. When the system provides active control in the roll direction (roll), the effect of the damping on the robot will be weakened. Damping is a nonlinear parameter, which will cause certain troubles in control. Weakening the effect of this item will improve the control accuracy of the system and help improve the suspension ability of the entire system.

[0070] In some embodiments, the propulsion duct 210 is arranged to be inclined outward from top to bottom. When the underwater robot is in the hovering process, after the first thruster 300 in the propulsion duct 210 is started, the water output from the propulsion duct 210 will flow to the outside of the frame 100 on the corresponding side. On the one hand, it ensures that the underwater robot has sufficient downward thrust to maintain its suspension, and on the other hand, it ensures that the underwater robot has good centering stability at the set position, which is more conducive to improving the overall suspension stability of the underwater robot.

[0071] In some embodiments, regarding the configuration of the propulsion duct 210 and the four first thrusters 300, the four propulsion ducts 210 are symmetrically arranged in the floating body 200 and spaced apart by a certain distance to ensure that the force arm from the first thruster 300 to the center of mass of the system is long enough.

[0072] The four first thrusters 300 can cooperate with each other to adjust the posture of the underwater robot. Through the cooperation between the propulsion duct 210 and the first thrusters 300, the suspension stability and the movement in the vertical swing direction can be ensured.

[0073] After the first propeller 300 is started, an upwardly inclined propulsion force will be generated. In actual use, by adjusting the action of the first propeller 300 at different positions, the three degrees of freedom of roll, pitch and heave can be adjusted.

[0074] Reference Figure 5 , the four first thrusters 300 are marked as a, b, c, and d respectively. When the four first thrusters 300 propel in the same direction, the underwater robot will move up and down in the direction of the vertical freedom degree, and the underwater robot will show a descending motion.

[0075] When the propulsion directions of the first propellers 300 on both sides (left and right) of the float 200 are opposite to each other, for example, the propulsion directions of a and b are forward, and the propulsion directions of c and d are reversed, the underwater robot will move in the direction of the roll freedom degree, and the underwater robot will roll clockwise or counterclockwise.

[0076] When the propulsion directions of the first propellers 300 at the two ends (referring to the front and rear ends) of the float 200 are opposite to each other, for example, the propulsion directions of a and c are forward, and the propulsion directions of b and d are reversed, the underwater robot will move in the direction of the pitch freedom, and the underwater robot will show a head-up or head-down movement.

[0077] During actual use, when the underwater robot needs to hover at a specific position, the four first thrusters 300 can cooperate to dynamically adjust the overall posture of the underwater robot, and then dynamically adjust the three degrees of freedom of bow roll, sway and pitch to meet the requirements of stable suspension.

[0078] At the same time, since the first propeller 300 is built into the propulsion duct, the instability of the underwater robot caused by the first propeller 300 being exposed and affected by the water flow can be further reduced, and the influence of the water flow on the hovering can be better reduced.

[0079] The specific inclination direction of the four propulsion ducts 210 is shown in FIG. Figure 8 and Fig. 9 , Figure 8 and Fig. 9 Only two propulsion ducts at the same end of the underwater robot are shown. Figure 8 This is a simplified view observed from the front side of the floating body 200. Fig. 9 It is a simplified view observed from the upper side of the floating body 200. The four first thrusters 300 form a vector layout, divided into two directions: primary and secondary.

[0080] In some embodiments, with the setting of four second thrusters 400, when the underwater robot is traveling underwater, by starting the second thrusters 400 at different positions, the underwater robot can move forward, backward, and freely rotate 360° in both directions underwater. In this way, the movement of the underwater robot in the three degrees of freedom of bow roll, lateral swing, and longitudinal swing can be guaranteed.

[0081] Reference Fig.10 , mark the four second thrusters 400 as e, f, g, and h. When g and e are propulsion in the positive direction and h and f are propulsion in the reverse direction, the underwater robot will move in the direction of the longitudinal freedom degree, and the underwater robot will show forward or backward movement.

[0082] When g and h are pushed in the positive direction and e and f are pushed in the negative direction, the underwater robot will move in the direction of the lateral freedom, and the underwater robot will move sideways to the left or right.

[0083] When g and f are pushed in the positive direction and h and e are pushed in the negative direction, the underwater robot will move in the direction of the bow pitch freedom, and the underwater robot will exhibit clockwise or counterclockwise rotation motion.

[0084] The longitudinal swing direction of the underwater robot is its main moving direction. In order to satisfy the underwater robot to exert control force during the lateral, longitudinal and bow swing movements, therefore, refer to Fig.10 The second propeller 400 is configured at an angle of 30° with the longitudinal swing direction (x-axis direction) of the robot in the horizontal direction, which can effectively improve the propulsion efficiency of the second propeller 400.

[0085] In some embodiments, the second propeller 400 is disposed on the inner side of the vertical frame 130 to prevent the second propeller 400 from protruding out of the frame 100 and being easily scratched by other external objects.

[0086] In some embodiments, regarding the setting of the cabin 500, multiple cabins 500 can be configured according to usage requirements, and batteries, controllers and other devices that need to be sealed and installed can be set in the cabin 500.

[0087] Reference Figure 4 The bottom frame 120 is provided with a plurality of mounting frames 140 at intervals along its length direction. The mounting frames 140 have a placement groove 141 with an open top. The cabin 500 is arranged in the placement groove 141 and is confined in the placement groove 141 by a strap 150, thereby achieving fixed installation of the cabin 500 on the bottom frame 120.

[0088] In some embodiments, when multiple cabins 500 are set, the mounting frame 140 spans the width direction of the bottom frame 120, and a plurality of placement grooves 141 are provided on the mounting frame 140. The multiple cabins 500 are arranged in a one-to-one correspondence with the plurality of placement grooves 141, that is, the multiple cabins 500 are fixedly arranged in sequence along the width direction of the bottom frame 120.

[0089] If the multiple cabins 500 cannot be arranged in sequence in the width direction of the bottom frame 120, the cabins can be stacked up and down and fixed with straps.

[0090] In some embodiments, for the configuration of other auxiliary accessories, refer to Figure 5 The floating body 200 is provided with a mounting groove 220, in which a sonar 710 is disposed, and the top of the sonar 710 is exposed from the mounting groove 220. The sonar 710 is located at the front end of the floating body 200, which improves the installation reliability of the sonar 710 on the one hand, and reduces the exposed volume of the sonar 710 as much as possible on the other hand.

[0091] In some embodiments, the vertical frame 130 is provided with a lighting device 720 and a camera device 730 to meet the requirements of underwater detection. The lighting device 720, the camera device 730 and the mechanical arm 600 are located on the same side of the frame 100, that is, at the front end of the underwater robot.

[0092] In some embodiments, in order to facilitate the adjustment of the buoyancy center and the center of gravity of the underwater robot according to different functional requirements, counterweight blocks 740 are respectively provided at the four bottom corners of the bottom frame 120 .

[0093] According to the distribution of different components installed on the frame 100, the weight of the counterweight block 740 is adjusted accordingly, thereby adjusting the weight distribution of the underwater robot to maximize the proximity of the center of mass and the center of buoyancy.

[0094] The weight distribution of the underwater robot is adjusted by configuring the counterweight block 740, so that the underwater robot can reduce the starting frequency of the first propeller 300 in the propulsion duct 210 when in a suspended state, thereby reducing energy consumption during use.

[0095] In some embodiments, the posture adjustment of the underwater robot adopts a robust control method, and the underwater robot can achieve multi-degree-of-freedom hovering control under the disturbance of the external environment.

[0096] The posture adjustment method of the underwater robot includes: establishing a multi-degree-of-freedom hydrodynamic model of the underwater robot

[0097] in, is the inertia matrix, is the additional mass matrix, is the damping matrix, It is the restoring force of the underwater robot. The underwater robot has six degrees of freedom, including: longitudinal swing, transverse swing, vertical swing, pitch, roll, and bow swing.

[0098] Define the 6 positions and angle components of the underwater robot in the geodetic coordinates (NED-Frame) to form the pose vector , the linear velocity and angular velocity components are defined in body coordinates (B-frame) to form the velocity vector , define 6 force and torque components to form the thrust vector . is the thrust vector generated by the external environment, is the thrust vector generated by the propeller. The inertia matrix M of the underwater robot is estimated using numerical calculation tools. RB , additional mass matrix M A and the damping matrix , specifically including:

[0099] Use mechanical design tools to determine the center of gravity of the underwater robot b , calculate the mass m and inertia parameters .

[0100] Use numerical calculation tools to cut the robot surface into triangular or quadrilateral micro-elements, and deduce the additional mass matrix of the underwater robot based on the slice calculation results. .

[0101] The damping term Divided into linear damping D and quadratic damping Two parts, , use computational fluid software (such as ANSYS-CFX or STAR-CCM+, etc.) to calculate the multi-degree-of-freedom damping force and torque parameters of the underwater robot.

[0102] According to the hydrodynamic modeling results, linear processing is performed to separate the control object and uncertainty parameters. The uncertainty set is sorted through linear fractional transformation (LFT) to convert the uncertainty parameters in the model into Arranged into the above LFT process, we get the generalized object:

[0103] .

[0104] in, is the system state vector, is the control input vector, representing the thrust torque input of the underwater robot . is the system output vector. Enter the vector for the external uncertainties. is the uncertainty output vector. According to the small gain theorem, , so the robust stability of the controlled object cluster with uncertainty is equivalent to the nominal generalized system stability, that is, the uncertainty factor can be disconnected, leaving the generalized system with uncertain parameters. Then the controller design is to find a feedback controller between the input signal u and the output signal y, so that after the controller and the generalized system with parameters form a closed-loop system, the closed-loop system satisfies the internal stability, such as Fig.11 shown.

[0105] Design a weight function based on the control objective and design a , , . Use bound function To cover the frequency band characteristics of the input and output signals, and realize the weighted constraints of control performance in the solution process. Arrange the transfer function matrix between the evaluation input w and the evaluation output z , , weighted controller The undesired signal gain will cause A larger objective function result can be obtained, and the corresponding controller result is also excluded in the control comprehensive optimization process.

[0106] Finding controllers using linear matrix inequalities or interval analysis methods , controller In addition to satisfying the robust stability of the closed-loop system, it is also necessary to evaluate the H relationship between the input w and the output z. ∞ The norm obtains the minimum value, that is, it satisfies :

[0107] .

[0108] In some embodiments, specific implementation examples and effects of the underwater robot's posture adjustment are as follows:

[0109] Organize the multi-degree-of-freedom model of the UVMS underwater robot:

[0110] The inertia matrix M of the underwater robot RB Solidworks calculation results (mass: kg, moment of inertia: ), as follows:

[0111] Additional mass matrix M A MCC hydrodynamic estimation results (mass: kg, moment of inertia: ), as follows:

[0112] The damping parameters are as follows:

[0113] Taking the heading direction as an example, the object description is as follows:

[0114] The parameters of the bow rolling model are as follows: Fig.12 shown.

[0115] In order to illustrate the actual anti-disturbance control effect of the underwater robot body and controller of the present invention, the traditional PID method is used to compare with the robust controller of the present invention. The results are shown in Figures 13 to 16 .H ∞ The robust controller is solved by LMI method, and the structural constraint robust controller is solved by interval analysis method. It can be seen from the experimental results that the underwater robot and control method involved in the present invention have better effects in controlling overshoot, adjustment time and robustness to uncertain influences. Specific indicators are as follows: Fig.17 shown.

[0116] The underwater robot can rise, float and turn more flexibly, and thus can navigate more flexibly underwater.

[0117] Compared with similar underwater robots in the prior art, the underwater robot provided by the present invention has the following main innovations:

[0118] Multiple degrees of freedom: Multiple degrees of freedom motion control is a key technical challenge that traditional underwater robots are difficult to overcome. The underwater robot in the present invention has more degrees of freedom of motion. The robot body except the robotic arm 600 has 6 degrees of freedom motion control capability. The float 200 and the thruster configuration are generated based on strict structural stability parameters and computational fluid dynamics analysis results.

[0119] Driving form: Underwater robots can be divided into under-actuated underwater robots and over-actuated underwater robots according to driving capabilities and forms. The robot body disclosed in the present invention has a vector combination arrangement of 8 thrusters (including 4 first thrusters 300 and 4 second thrusters 400), which is a typical over-driven configuration, and can generate 6-degree-of-freedom motion control capabilities regardless of hovering or moving.

[0120] Thruster combination: Thrust distribution technology is the key point of the multi-degree-of-freedom underwater robot control method. The thruster vector combination form disclosed in the present invention must first meet the basic conditions of being able to generate thrust and thrust torque in 6 degrees of freedom. Secondly, the appearance design of the present invention provides a propulsion duct 210 for the four first thrusters 300 in a limited space on the basis of reducing water resistance and improving the accuracy of parameter calculation, thereby improving the efficiency of energy conversion when the thruster pushes water. In addition, the standard cylindrical through-hole shape of the propulsion duct 210 also improves the accuracy of thrust parameter calculation and analysis. The inclined arrangement of the four first thrusters 300 at the top of the present invention can produce a superposition effect of four thrust vectors, which can generate large thrust in the roll, pitch and heave directions. This arrangement makes the posture of this robot extremely flexible.

[0121] Structural stability: The present invention adopts a rectangular shape. Under the condition of optimizing water resistance, the design has significant structural stability and load-bearing capacity. The supporting structure of this structural design can provide more than several hundred kilograms of supporting force for the overall frame. Experiments have found that large-load prototypes can stand stably and reliably.

[0122] Carrying load capacity: The present invention can provide a larger bottom load space and carrying capacity.

[0123] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0124] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An underwater robot, characterized in that: include: A frame, which is a rectangular frame structure, including a top frame, a bottom frame, and a vertical frame arranged between the top frame and the bottom frame, wherein the vertical frame is located at four corners of the rectangular frame structure; A cabin body is arranged on the bottom frame, and the cabin body is extended along the length direction of the bottom frame; A floating body, which is arranged on the top frame, and the floating body is a rectangular structure. The floating body is provided with propulsion ducts passing through from top to bottom at positions near the four corners thereof. The top opening of the propulsion duct is a water inlet, and the bottom opening of the propulsion duct is a water outlet. The four propulsion ducts are symmetrically arranged around the center of the floating body, and each of the propulsion ducts extends obliquely from bottom to top toward the center of the floating body; four first propellers, each of the propulsion ducts being provided with one of the first propellers; Four second propellers, each of the vertical frames is provided with one second propeller, the four second propellers are symmetrically arranged, the second propellers are arranged in a horizontal direction and are inclined relative to the length extension direction of the frame; A mechanical arm, which is arranged on the width side of the bottom frame; The underwater robot posture adjustment method comprises: establishing a multi-degree-of-freedom hydrodynamic model of the underwater robot , in, is the inertia matrix, is the additional mass matrix, is the damping matrix, is the restoring force of the underwater robot, and the underwater robot has six degrees of freedom of motion, including longitudinal swing, transverse swing, vertical swing, pitch, roll, and bow pitch; Define the six positions and angle components of the underwater robot in geodetic coordinates to form a pose vector , linear velocity and angular velocity components are defined in body coordinates to form the velocity vector , define 6 force and torque components to form the thrust vector , is the thrust vector generated by the external environment, τ pro is the thrust vector generated by the thruster, and the inertia matrix M of the underwater robot is estimated using numerical calculation tools. RB , additional mass matrix M A and the damping matrix ,include: Use mechanical design tools to confirm the center of gravity position of the underwater robot b , calculate the mass m and inertia parameters ; Use numerical calculation tools to cut the surface of the underwater robot into triangular or quadrilateral micro-elements, and deduce the additional mass matrix of the underwater robot based on the slice calculation results. ; The damping term Divided into linear damping D and quadratic damping Two parts, , using computational fluid software to calculate the multi-degree-of-freedom damping force and torque parameters of underwater robots; According to the hydrodynamic modeling results, linear processing is performed to separate the control object and uncertainty parameters, and the uncertainty set is sorted through linear fractional transformation to convert the uncertainty parameters in the model into Arranged into the linear fraction change process, we get the generalized object: ; in, is the system state vector, is the control input vector, representing the thrust torque input τ of the underwater robot, is the system output vector, is the external uncertainty input vector, is the uncertainty output vector, ; Design a weight function based on the control objective and design a , , ; Use bound function To cover the frequency band characteristics of the input and output signals, organize the transfer function matrix between the evaluation input w and the evaluation output z ; Finding controllers using linear matrix inequalities or interval analysis methods , Controller meets : 。 2. The underwater robot according to claim 1, characterized in that: The thickness of the floating body is smaller than the length and width of the floating body. The width of the floating body is equal to the width of the top frame, and the length of the floating body is equal to the length of the top frame.

3. The underwater robot according to claim 1, characterized in that: A mounting groove is arranged in the buoy, a sonar is arranged in the mounting groove, and a top of the sonar is exposed from the mounting groove.

4. The underwater robot according to claim 1, characterized in that: The second propeller is arranged on the inner side of the vertical frame.

5. The underwater robot according to claim 1, characterized in that: The vertical frame is provided with an illumination device and a camera device, and the illumination device, the camera device and the mechanical arm are located on the same side of the frame.

6. The underwater robot according to claim 1, characterized in that: The bottom frame is provided with a plurality of mounting frames at intervals along the length direction thereof. The mounting frames are provided with placement grooves with open tops. The cabin body is arranged in the placement grooves and is restricted in the placement grooves by binding straps.

7. The underwater robot according to claim 6, characterized in that: The mounting frame spans the width direction of the bottom frame, and a plurality of placement slots are provided on the mounting frame; There are a plurality of cabins, and the plurality of cabins are arranged in one-to-one correspondence with the plurality of placement slots.

8. The underwater robot according to claim 1, characterized in that: Counterweight blocks are respectively arranged at the four corners of the bottom of the bottom frame.

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