An amphibious robot
By combining an inner shell, a propeller, and a rolling outer shell, along with a counterweight and a motor drive, a simplified drive system for amphibious robots has been achieved. This solves the problems of complex structure and insufficient adaptability in existing technologies, enabling efficient and reliable multi-environment movement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XI AN JIAOTONG UNIV
- Filing Date
- 2025-05-30
- Publication Date
- 2026-06-16
AI Technical Summary
Existing amphibious robots have complex drive systems that are difficult to miniaturize, and they lack adaptability and reliability in different environments.
It adopts a combined structure of inner shell, propeller and rolling outer shell, and realizes amphibious movement through a drive system. It uses counterweight and motor to provide power torque and reaction force for propulsion, and simplifies the control system.
It achieves high-speed and efficient movement in both aquatic and terrestrial environments, simplifies structural design, improves the robot's reliability and environmental adaptability, enhances internal space utilization, and adapts to complex terrain and fluid environments.
Smart Images
Figure CN120396568B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of amphibious robot technology, and in particular to an amphibious robot. Background Technology
[0002] Amphibious robots, with their ability to move on both land and water, can perform a variety of tasks in complex environments where land and water meet, such as monitoring, exploration, pollution detection, and search and rescue, making them a popular research area in modern technology. However, the complex operating environment of amphibious systems presents significant challenges to the design and development of amphibious robots, placing high demands on their driving principles, structural design, and power systems.
[0003] Currently, there are two design approaches for amphibious robot drive systems: 1. The robot has multiple drive systems, which can be switched to adapt to the new environment and drive the robot when the working environment changes; 2. The robot is equipped with only one integrated drive system, which enables the robot to move in both land and water environments simultaneously.
[0004] Amphibious robots equipped with multiple independent drive systems are typically structurally and controlically complex, placing higher demands on miniaturization. Examples include foot-propeller hybrid and foot-jet propulsion amphibious robots, which use foot-driven propulsion on land and independent propellers or jet propulsion systems in water. Some amphibious robots combine multiple independent drive systems and redesign them, such as those using foot-paddle, foot-fin, or wheel-paddle-fin drive systems. However, this design does not completely overcome the drawbacks of multiple drive systems, and the drive control system remains complex. In contrast, another type of amphibious robot does not require switching between structural or drive systems in both land and water environments. This includes tracked, spherical, and biomimetic amphibious robots. Tracked amphibious robots have good obstacle-crossing capabilities and high load-bearing capacity, but slow movement speed and inability to move underwater. Spherical amphibious robots, while highly maneuverable in both land and water, have poor obstacle-crossing ability and complex control; their movement mechanisms require further research. Finally, some amphibious robots employ biomimetic structural designs, which offer high drive efficiency but complex control and poor reliability.
[0005] Based on the above problems, it is necessary to improve existing amphibious robots. Summary of the Invention
[0006] To address the aforementioned technical problems, this invention provides an amphibious robot that simplifies its drive system and control system.
[0007] This invention provides an amphibious robot, comprising: a body and a propulsion mechanism, a steering mechanism, and a pitching mechanism respectively connected thereto. The body includes an inner shell, a propeller, and a rolling outer shell, sequentially fitted from the inside out. The inner shell is cylindrical. The propulsion mechanism includes a support frame, a drive motor, and a first counterweight. The stator of the drive motor is fixed to the side of the support frame, and the first counterweight is fixed to the bottom of the support frame. The inner shell is fitted over the support frame, and its side is connected to the rotor of the drive motor. One side of the inner shell is connected to the rotor of the drive motor, and the other side is rotatably connected to the support frame. The rotation of the stator drives the first counterweight to rotate, providing torque to the body. The rotation of the rotor drives the inner shell, propeller, and rolling outer shell to rotate synchronously, propelling the robot to move on the water surface / in water by reaction force.
[0008] Optionally, the rolling outer shell includes two detachably connected cylindrical units, the outer walls of the two integrally connected cylindrical units being arc-shaped along their axis from the middle to both sides, and the inner shell includes two detachably connected cylindrical units.
[0009] Optionally, the propeller includes multiple blades, which are spaced apart axially along the inner shell, each blade extending radially along the inner shell, and the multiple blades forming an axial spiral shape.
[0010] Optionally, the length of the first counterweight along the axial direction of the rolling housing is not less than % of the length of the rolling housing, and the first counterweight is fixed to the outer wall of the bracket.
[0011] Optionally, the steering mechanism includes a steering motor and a second counterweight. The steering motor is fixed at the top center of the bracket, and the output shaft of the steering motor is fixed to the second counterweight. There is a gap between the second counterweight and the bracket.
[0012] Optionally, the pitch mechanism includes a stepper motor, a horizontal moving component, and a third counterweight. The stepper motor is fixed to one end of the top of the bracket. The input end of the horizontal moving component is connected to the stepper motor, and the output end of the horizontal moving component is connected to the third counterweight. The moving direction of the third counterweight is parallel to the axis of the inner shell.
[0013] Optionally, the horizontal moving component includes a base and a lead screw. The base is fixed to the outer side of the top of the bracket, the lead screw is rotatably connected to the base, one end of the lead screw is connected to a stepper motor, and a third counterweight is screwed to the lead screw.
[0014] Optionally, bullet-shaped end shells are fixed to both ends of the inner shell, with the end shells extending out of the end of the rolling outer shell.
[0015] Optionally, one side of the inner shell is fixedly connected to the rotor of the drive motor via a connector, and the other side of the inner shell is rotatably connected to the bracket via a connector. The connector is a cross-shaped metal piece, and the two sides of the inner shell are provided with cross-shaped grooves, into which the cross-shaped metal piece is inserted.
[0016] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art:
[0017] This invention provides an amphibious robot that simplifies its drive and control systems, sharing a single drive system for both water and land applications. The robot's structure is designed with an inner shell, propeller, and rolling outer shell nested together from the inside out. A first counterweight is fixed to the bottom of the support frame. When the drive motor starts, its stator rotates the support frame and all components fixed to it by a certain angle. The rotation of the first counterweight provides the robot's torque, while the rotor drives the robot body, thus enabling the robot to rotate against the resistance torque of the fluid / land. The propeller, during rotation, deflects surrounding water backward, relying on reaction force... The robot is propelled by force to move on the water surface / underwater, and its rolling outer shell allows it to roll forward on land. This amphibious robot has a simple structural design and requires only one drive system and control system, ensuring high reliability in harsh environments. At the same time, the simple system design allows the robot to retain more internal space for the deployment of different functional modules such as surveying and communication. Furthermore, the amphibious robot can move at high speed in both water and land environments, enabling it to perform various tasks faster and more efficiently. It can move and switch motion modes in multiple working environments such as land, water surface, and underwater, and can adapt to various complex terrains and fluid environments, making it suitable for a wide range of applications. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the overall structure of an amphibious robot provided in an embodiment of the present invention;
[0019] Figure 2 for Figure 1 Sectional view along the middle AA direction;
[0020] Figure 3 This is a schematic diagram of the internal overall structure of an amphibious robot provided in an embodiment of the present invention;
[0021] Figure 4 A side view of an amphibious robot with its end shell removed, provided in an embodiment of the present invention;
[0022] Figure 5 for Figure 1 Sectional view along the BB direction.
[0023] Explanation of reference numerals in the attached figures:
[0024] 1. Inner shell; 2. End shell; 3. Propeller; 4. Rolling outer shell; 5. Groove; 6. Bracket; 7. First counterweight; 8. Second counterweight; 9. Battery; 10. Steering motor; 11. Drive motor; 12. Stepper motor; 13. Lead screw; 14. Third counterweight; 15. Coupling; 16. Bearing; 17. Connector; 18. Motor control board. Detailed Implementation
[0025] The following detailed description of a specific embodiment of the present invention is provided in conjunction with the accompanying drawings. However, it should be understood that the scope of protection of the present invention is not limited to the specific embodiment.
[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the technical solution of this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0027] The present invention will be described below through several specific embodiments. To keep the following description of the embodiments clear and concise, detailed descriptions of known functions and components may be omitted. When any component of an embodiment of the present invention appears in more than one drawing, the component may be represented by the same reference numerals in each drawing.
[0028] This invention addresses the problems of existing amphibious robots, such as complex cross-media motion drive mechanisms, difficulty in miniaturization, and weak adaptability to multi-obstacle terrain environments. It proposes an amphibious robot that simplifies the drive system and its control system, enabling it to move efficiently in various environments such as land, water surface, and underwater, and has the ability to adapt to complex amphibious scenarios.
[0029] refer to Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a schematic diagram of the overall structure of an amphibious robot provided in an embodiment of the present invention. Figure 2 for Figure 1 Sectional view along the AA direction. Figure 3 This is a schematic diagram of the internal overall structure of an amphibious robot provided in an embodiment of the present invention, as shown below. Figure 1 , Figure 2 and Figure 3As shown, this embodiment of the invention provides an amphibious robot, including: a body and a propulsion mechanism, a steering mechanism, and a pitching mechanism respectively connected thereto. The body includes an inner shell 1, a propeller 3, and a rolling outer shell 4, sequentially fitted from the inside out. The inner shell 1 is cylindrical, and the propeller 3 is fixed to the outer periphery of the inner shell 1. The propeller 3 can use variable pitch blades, and its angle of attack can be adjusted by a micro-servo motor inside the inner shell 1 to achieve amphibious operation. The rolling outer shell 4 is coaxially fitted around the outer periphery of the inner shell 1 and fixed to the outer edge of the propeller 3. The propulsion mechanism includes a bracket 6, a drive motor 11, and a first counterweight 7. The drive motor 11 is an IP68 waterproof servo motor, with the stator windings encapsulated in epoxy resin and the rotor shaft fitted with a mechanical seal. The stator of the drive motor 11 is fixed to the side of the bracket 6, and the first counterweight 7 is fixed to the bottom of the bracket 6. The inner shell 1 is fitted onto the support 6. One side of the inner shell 1 is connected to the rotor of the drive motor 11, and the other side is rotatably connected to the support 6. The rotation of the stator drives the first counterweight 7 to rotate, providing torque to the body. The rotation of the rotor drives the inner shell 1, propeller 3 and rolling outer shell 4 to rotate synchronously. The reaction force propels the robot to move on the water surface / in water. The surface of the rolling outer shell 4 can be equipped with anti-slip textures or deformable scale structures to increase friction in land mode and automatically fit to reduce turbulence in underwater mode. The first counterweight 7 can be hollow and filled with phase change material. When the temperature is high, it absorbs heat and melts to lower the center of gravity and improve the ability to resist wind and waves. The gyroscopic effect generated by the stator-counterweight system stabilizes the body, and the rotor-propeller system provides propulsion. The two achieve power decoupling through opposite rotation, reducing energy consumption by 40%.
[0030] This invention provides an amphibious robot that simplifies its drive and control systems, sharing a single drive system for both water and land applications. The robot's structure is designed with an inner shell, propeller, and rolling outer shell nested together from the inside out. A first counterweight is fixed to the bottom of the support frame. When the drive motor starts, its stator rotates the support frame and all components fixed to it by a certain angle. The rotation of the first counterweight provides the robot's torque, while the rotor drives the robot body, thus enabling the robot to rotate against the resistance torque of the fluid / land. The propeller, during rotation, deflects surrounding water backward, relying on reaction force... The robot is propelled by force to move on the water surface / underwater, and its rolling outer shell allows it to roll forward on land. This amphibious robot has a simple structural design and requires only one drive system and control system, ensuring high reliability in harsh environments. At the same time, the simple system design allows the robot to retain more internal space for the deployment of different functional modules such as surveying and communication. Furthermore, the amphibious robot can move at high speed in both water and land environments, enabling it to perform various tasks faster and more efficiently. It can move and switch motion modes in multiple working environments such as land, water surface, and underwater, and can adapt to various complex terrains and fluid environments, making it suitable for a wide range of applications.
[0031] Refer again Figure 2 The rolling shell 4 comprises two detachably connected cylindrical units, made of high-strength, lightweight materials (such as carbon fiber or titanium alloy), and connected by threads for easy disassembly and maintenance. The outer walls of the two integrated cylindrical units are arc-shaped, converging from the center to both sides along their axis. The outer walls of the two cylindrical units are streamlined arc-shaped, wider in the middle and narrower at both ends, conforming to hydrodynamic design, reducing water resistance, and enhancing stability when rolling on land. The rolling shell 4 can be embedded with a shape memory alloy (SMA) skeleton, which can finely adjust its curvature under specific temperature or electrical signal stimulation to optimize motion efficiency in different media (water / land / mud). A telescopic auxiliary mechanism can be integrated in the middle of the rolling shell 4. The wheels automatically deploy in complex terrain (such as sand and gravel) to prevent sinking into soft ground. The inner shell 1 consists of two detachably connected cylindrical units, which are detachably connected by threads to facilitate the installation of the internal structure. The inner shell 1 can be made of carbon fiber-Kevlar composite material, which balances lightweight and impact resistance. The interior is filled with porous energy-absorbing foam to buffer the shock waves of underwater explosions or collisions. The inner shell 1 and the support 6 can be connected by a magnetic levitation bearing to reduce mechanical friction and reduce the energy consumption of the drive motor 11. The outer wall of the rolling outer shell 4 is arc-shaped along its axis from the middle to both sides, which can reduce the resistance of movement in water. Moreover, this shape of the rolling outer shell 4 makes it easier to turn on land.
[0032] Specifically, the propeller 3 includes multiple blades, which are spaced apart along the axial direction of the inner shell 1. Each blade extends radially along the inner shell 1, and the multiple blades form an axial spiral shape. For example, four blades can be set and distributed equidistantly along the axial direction of the inner shell 1. Each blade can have a radially extending airfoil cross section, balancing thrust and efficiency. The blades can adopt a variable pitch design, with a larger pitch near the root of the inner shell 1 to provide strong thrust, and a smaller pitch at the blade tip to reduce cavitation effect and reduce underwater noise. The blade surface can be covered with a sharkskin-like microgroove coating to reduce turbulence resistance and improve underwater propulsion efficiency by 10% to 15%. The propulsion force of multiple blades forming an axial spiral shape moving in the fluid is large.
[0033] Refer again Figure 3 The length of the first counterweight 7 along the axial direction of the rolling outer shell 4 is not less than 83% of the length of the rolling outer shell 4, and the first counterweight 7 is fixed to the outer wall of the bracket 6. The length of the first counterweight 7 is almost through the robot. The longer it is, the greater the driving torque it can provide, provided that space allows. Theoretically, the farther the center of mass of the first counterweight 7 is from the axis of the entire robot, the better, as the farther away it is, the greater the driving torque it provides.
[0034] Optionally, the steering mechanism includes a steering motor 10 and a second counterweight 8. The steering motor 10 is fixed at the top center of the support 6, which enables the robot to keep its center of gravity in the middle at the beginning. The output shaft of the steering motor 10 is fixed to the second counterweight 8. There is a gap between the second counterweight 8 and the support 6. The larger the diameter and the higher the height of the cylindrical second counterweight 8, the better. However, the actual design is limited by space.
[0035] Steering motion: When the steering motor 10 is working, its rotor drives the second counterweight 8 to rotate and generate angular acceleration. At the same time, according to the conservation of angular momentum, the entire robot also generates angular acceleration in the opposite direction to the rotation direction of the second counterweight 8, thereby driving the robot to turn in fluid and land environments.
[0036] Optionally, the pitch mechanism includes a stepper motor 12, a horizontal moving component, and a third counterweight 14. The stepper motor 12 is fixed to one end of the top of the bracket 6, which allows the robot's center of gravity to be kept in the middle at the beginning. The input end of the horizontal moving component is connected to the stepper motor 12, and the output end of the horizontal moving component is connected to the third counterweight 14. The moving direction of the third counterweight 14 is parallel to the axis of the inner shell 1.
[0037] Pitch motion in fluid: When the stepper motor 12 above the support 6 is working, it drives the third counterweight 14, which is connected to the horizontal moving component, to move linearly along the robot's axis, thereby changing the robot's center of gravity position. When the movement direction of the third counterweight 14 is the same as the robot's movement direction, the robot's head tilts downward, and the robot moves downward in the water. When the movement direction of the third counterweight 14 is opposite to the robot's movement direction, the robot's head tilts upward, and the robot moves upward in the water. After the robot floats to the surface, it can move stably on the water surface. In addition, when the robot moves on land, the stepper motor 12 can also drive the third counterweight 14 to move to the tail, changing the robot's center of gravity position to achieve a larger turning radius.
[0038] In this embodiment, the horizontal moving component includes a base and a lead screw 13. The base is fixed to the outer top of the bracket 6, and the lead screw 13 is rotatably connected to the base. One end of the lead screw 13 is connected to the stepper motor 12 through a coupling 15. The third counterweight 14 is screwed to the lead screw 13. Using a lead screw and nut has the following advantages: 1) High precision, which is conducive to fine adjustment of the robot's center of gravity; 2) High rigidity and transmission efficiency; 3) Good performance at high speed, which is conducive to rapid adjustment of the robot's center of gravity; 4) Small space occupation, which is conducive to the miniaturization of the robot.
[0039] Optionally, bullet-shaped end shells 2 are fixed to the two ends of the inner shell 1, which can reduce the resistance encountered by the robot in the fluid. The end shells 2 extend out of the end of the rolling outer shell 4.
[0040] refer to Figure 4 and Figure 5 , Figure 4 for Figure 1 Sectional view along the BB direction. Figure 5 This is a schematic diagram of the internal overall structure of an amphibious robot provided in an embodiment of the present invention, as shown below. Figure 4 and Figure 5 As shown, one side of the inner shell 1 is fixedly connected to the rotor of the drive motor 11 via a connector 17, and the other side of the inner shell 1 is rotatably connected to the bracket 6 via a connector 17. The connector 17 is a cross-shaped metal piece. The two sides of the inner shell 1 are provided with cross-shaped grooves 5, and the cross-shaped metal pieces are inserted into the grooves 5. The battery 9 is fixed inside the bracket 6 on the side close to the stepper motor 12, and the motor control board 18 is set on the opposite side of the bracket 6.
[0041] This invention provides an amphibious robot with an inner shell 1 consisting of four symmetrically distributed propeller blades and a rolling outer shell 4 composed of eight arc-shaped parts. The robot utilizes the reaction force between the rotating propellers 3 and the water to propel it efficiently in the fluid, while the rolling outer shell 4 enables land-based movement. This simplifies the motion mechanism, allowing it to operate in complex amphibious environments. The robot utilizes the conservation of angular momentum for drive and steering, and achieves surface / underwater operation by changing the center of mass position, resulting in simple control. This robot integrates amphibious movement, a simple motion mechanism, small size and weight (see Table 1 for comparison), and flexible surface / underwater movement switching, solving problems such as complex structure, cumbersome control, inconvenient deployment and retrieval, complex drive principles, poor maneuverability, weak environmental adaptability, and difficulty in guaranteeing reliability found in existing amphibious robots. A detailed analysis follows:
[0042] 1) From the perspective of integrated drive principle, the amphibious robot provided by this invention has a simple structural design and only requires one set of motion drive and control system, which can ensure the high reliability of the robot in harsh environments. At the same time, the simple system design will allow the robot to retain more internal space for the deployment of different functional modules such as surveying and communication.
[0043] 2) From the perspective of mobility, the amphibious robot provided by this invention can move at high speed in both aquatic and terrestrial environments, and can perform various tasks faster and more efficiently;
[0044] 3) In terms of environmental adaptability, this amphibious robot can move and switch motion modes in multiple working environments such as land, water surface and underwater. It can adapt to various complex terrains and fluid environments and has a wide range of applications.
[0045] Table 1. Amphibious robots developed by domestic and foreign institutions and their dimensions
[0046]
[0047] This invention provides an amphibious robot that integrates advantages such as miniaturization, simple motion mechanism, ease of control, efficient and flexible movement, strong environmental adaptability, and reliable operation. It solves the problems commonly found in current amphibious robots, including complex structure, cumbersome control, inconvenient deployment and retrieval, complex drive principles, poor maneuverability, weak environmental adaptability, and difficulty in guaranteeing reliability. This enables the robot to replace humans in complex application scenarios such as hydrological surveying, emergency rescue, aquaculture, and pipeline inspection, reducing the risk of human injury and death, and achieving higher work efficiency, thus completing tasks better and more reliably.
[0048] The above inventions are merely a few specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.
Claims
1. An amphibious robot, characterized in that, include: The fuselage and the propulsion mechanism, steering mechanism, and pitch mechanism connected to it respectively, among which, The fuselage includes an inner shell (1), a propeller (3) and a rolling outer shell (4) that are sequentially fitted from the inside to the outside. The inner shell (1) is cylindrical. The pushing mechanism includes a bracket (6), a drive motor (11) and a first counterweight (7). The stator of the drive motor (11) is fixed to the side of the bracket (6), the first counterweight (7) is fixed to the bottom of the bracket (6), the inner shell (1) is fitted outside the bracket (6), one side of the inner shell (1) is connected to the rotor of the drive motor (11), and the other side is rotatably connected to the bracket (6). The rotation of the stator drives the first counterweight (7) to rotate, providing torque to the body. The rotation of the rotor drives the inner shell (1), propeller (3) and rolling outer shell (4) to rotate synchronously, relying on the reaction force to propel the robot to move on the water surface / in the water. The gyroscopic effect generated by the stator-first counterweight (7) system stabilizes the fuselage, while the rotor-propeller (3) system provides propulsion. The two systems achieve power decoupling through opposite rotation. The steering mechanism includes a steering motor (10) and a second counterweight (8). The steering motor (10) is fixed at the top center of the bracket (6). The output shaft of the steering motor (10) is fixed to the second counterweight (8). There is a gap between the second counterweight (8) and the bracket (6). The pitch mechanism includes a stepper motor (12), a horizontal moving component, and a third counterweight (14). The stepper motor (12) is fixed to one end of the top of the bracket (6). The input end of the horizontal moving component is connected to the stepper motor (12), and the output end of the horizontal moving component is connected to the third counterweight (14). The moving direction of the third counterweight (14) is parallel to the axis of the inner shell (1).
2. The amphibious robot as described in claim 1, characterized in that, The rolling outer shell (4) includes two detachably connected cylindrical units. The outer walls of the two integrally connected cylindrical units are arc-shaped, converging from the middle to both sides along their axis. The inner shell (1) includes two detachably connected cylindrical units.
3. An amphibious robot as described in claim 1, characterized in that, The propeller (3) includes multiple blades, which are spaced apart along the inner shell (1) axially. Each blade extends radially along the inner shell (1), and the multiple blades form an axial spiral shape.
4. An amphibious robot as described in claim 1, characterized in that, The length of the first counterweight (7) along the axial direction of the rolling shell (4) is not less than 83% of the length of the rolling shell (4), and the first counterweight (7) is fixed to the outer wall of the bracket (6).
5. An amphibious robot as described in claim 1, characterized in that, The horizontal moving component includes a base and a lead screw (13). The base is fixed to the outer side of the top of the bracket (6). The lead screw (13) is rotatably connected to the base. One end of the lead screw (13) is connected to the stepper motor (12). The third counterweight (14) is screwed to the lead screw (13).
6. An amphibious robot as described in claim 1, characterized in that, The inner shell (1) is fixed to the two ends of the inner shell (1) with bullet-shaped end shells (2), and the end shells (2) extend out of the end of the rolling outer shell (4).
7. An amphibious robot as described in claim 1, characterized in that, One side of the inner shell (1) is fixedly connected to the rotor of the drive motor (11) via a connector (17), and the other side of the inner shell (1) is rotatably connected to the bracket (6) via a connector (17). The connector (17) is a cross-shaped metal piece. The two sides of the inner shell (1) are provided with cross-shaped grooves (5), and the cross-shaped metal piece is inserted into the grooves (5).