An amphibious bionic robotic fish

Abstract

The application discloses an amphibious bionic robotic fish, and belongs to the technical field of bionic robots. The fish body, the main frame, the tail fin driving structure, the pectoral fin driving structure, the linkage type multi-legged structure integrated in the fish body and the hatch structure are included. The hatch structure includes a hatch and a hatch driving mechanism. When the hatch is opened, the multi-legged structure is exposed for land walking. When the hatch is closed, the fish body is streamlined for underwater movement. The linkage type multi-legged structure is composed of four four-legged modules. Each four-legged module contains a double-crank rocker mechanism. The double-crank has a 180° phase difference to ensure walking stability. Four independent power sources are used to drive walking and differential steering. The tail fin driving structure realizes passive swinging of the tail fin through a tension spring. The pectoral fin driving structure assists in adjusting the underwater posture. The linkage type multi-legged structure is integrated in the fish body without the need for external additional modules or complex deformation mechanisms. The structure is compact, the water-land mode switching is reliable, the motion stability is strong, the water-land cross-medium moving task can be autonomously completed, and the application is suitable for underwater detection, environmental monitoring and other fields.

Description

Technical Field

[0001] This invention relates to the field of biomimetic robot technology, specifically to a robotic fish device that achieves underwater and land movement through an internally integrated tail fin drive structure and a linkage-type multi-legged structure. Background Technology

[0002] Existing biomimetic robotic fish mainly focus on underwater movement, using the mimicking of fish tail fin movements, pectoral fin movements, or body undulations for propulsion. However, they have significant limitations: they can only operate in underwater environments. Once they need to be transferred from water to land, such as mudflats or shorelines, they completely lose their mobility and cannot autonomously complete cross-media tasks, such as requiring manual retrieval after underwater exploration.

[0003] In the development of this technical field, there are three main types of existing amphibious mobile devices, but all of them have shortcomings related to the technical defects solved by this invention:

[0004] Pure robotic fish with external auxiliary modules: Traditional robotic fish achieve underwater propulsion through biomimetic fins and tail fins. If land movement is required, external mobility mechanisms such as wheels or tracks are usually added. However, this approach results in a bulky structure. External auxiliary modules increase the overall size and weight, significantly increasing drag during water movement. When moving on land, maneuverability (such as obstacle crossing and turning) is reduced due to the inertia of the added modules. Furthermore, the connection between the auxiliary modules and the fish body requires additional sealing design, increasing potential points of failure and manufacturing costs.

[0005] Multi-legged robot with watertight shell solution: This solution uses a multi-legged robot as the core, covered by a watertight shell to achieve underwater propulsion. However, the multi-legged robot's own land-based walking mechanism consumes too much energy when moving in water due to fluid resistance and exposed mechanical structures. At the same time, the coordination between the watertight shell and the movement of the legs requires complex sealing and transmission designs, resulting in a high failure rate when switching between underwater and land modes. Furthermore, the internal space is divided by separate watertight structures and walking mechanisms, requiring redundant placement of electronic components such as batteries and controllers, further increasing cost and weight.

[0006] Deformable structure solution: Some designs attempt to switch between land and water modes through mechanical deformation, such as folding and unfolding the feet. However, the deformation mechanism involves complex mechanical linkages such as multi-links and drive motors, resulting in low system reliability (the increased number of moving parts leads to a higher failure rate). Moreover, the deformation process is time-consuming and energy-intensive, and the continuity of movement is poor. At the same time, the deformable structure greatly restricts the internal space layout, and electronic components and power systems cannot be efficiently integrated, thus limiting the range.

[0007] The core deficiency of the aforementioned existing technologies lies in the failure to integrate the internal functions of biomimetic propulsion and multi-legged terrestrial walking, resulting in structural redundancy, low mobility, poor reliability, and high costs. This invention, by integrating a multi-legged structure internally, fundamentally solves these deficiencies, achieving lightweight, efficient, and reliable amphibious movement. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an amphibious biomimetic robotic fish. Through the design of an internally integrated linkage multi-leg structure, it achieves high efficiency, reliability and compactness of amphibious function, and solves the key problems of structural redundancy, low efficiency, insufficient reliability and high cost in the existing technology.

[0009] Therefore, this invention proposes an amphibious biomimetic robotic fish, comprising a fish body, a main frame, a tail fin drive structure, and a pectoral fin drive structure, and further comprising:

[0010] A linkage-type multi-legged structure is integrated inside the fish's body for walking on land;

[0011] The hatch structure includes a hatch and a hatch drive mechanism, which drives the hatch to open or close. When the hatch is open, the linkage-type multi-leg structure is exposed, and when the hatch is closed, the fish body forms a streamlined shape.

[0012] As a preferred technical solution of this application, the linkage-type multi-leg structure is composed of four four-legged modules, each of the four-legged modules including a transmission structure and a crank-rocker structure; the crank-rocker structure consists of a lower leg rod, a connecting rod, a upper leg rod, a rocker arm, a crank, and a frame forming a single leg, two single legs are symmetrically placed and share a crank to form a crank-rocker structure, and two crank-rocker structures are symmetrically placed to form the four-legged module.

[0013] As a preferred technical solution of this application, each of the four-legged modules is driven by an independent power source, the power source including a four-legged module drive motor and a reducer, the output end of the reducer is connected to a bevel gear two via a key, the bevel gear two meshes with a bevel gear one, the bevel gear one and the spur gear two are connected to a transmission shaft via a key, the spur gear two meshes with a spur gear one, the spur gear one is mounted on a crank transmission shaft, and transmits power to the crank.

[0014] As a preferred technical solution of this application, the two cranks in each quadruped module are mounted on the same crank drive shaft and have a phase difference of 180°; by adjusting the speed difference of the independent power sources of the four quadruped modules, the robotic fish can turn on land.

[0015] As a preferred technical solution of this application, the hatch drive mechanism includes a hatch waterproof drive servo and a gear transmission group. The gear transmission group includes output gear three, gear one, gear two and gear four. The hatch waterproof drive servo is connected to the main frame through a bracket. Its output end is connected to output gear three through a small disc. Output gear three meshes with gear one. Gear one, gear two and gear four are mounted on the hatch drive shaft. The hatch is connected to the hatch drive shaft through a hatch connecting block.

[0016] As a preferred technical solution of this application, the tail fin drive structure includes a waterproof tail fin drive servo, a tail fin transmission bracket, a tension spring, and a tail fin connecting block. The waterproof tail fin drive servo is fixed on the main frame, and its output end is connected to the tail fin transmission bracket via a connecting disc. The tail fin is mounted on the main frame via the tail fin connecting block. One end of the tension spring is connected to the connecting column of the tail fin transmission bracket, and the other end is connected to the tail fin connecting block, so that the tail fin and the tail fin transmission bracket form a non-rigid connection, realizing passive oscillation. The robotic fish turns underwater through differential control of the waterproof tail fin drive servo.

[0017] As a preferred technical solution of this application, the pectoral fin drive structure includes a pectoral fin waterproof drive servo, a pectoral fin drive shaft, a second bearing, and a pectoral fin fastener; the pectoral fin waterproof drive servo is installed on the hatch, and its power is transmitted to the pectoral fin through the pectoral fin drive shaft, and the second bearing is installed on the pectoral fin drive shaft.

[0018] As a preferred technical solution of this application, it also includes a waterproof control compartment, a waterproof lithium battery compartment, a switch, a charging interface, and a wireless communication module integrated on the main frame.

[0019] As a preferred technical solution of this application, the fish body includes a fish head, a fish body, a fish tail, a dorsal fin, and a fish shell. The dorsal fin is installed on the fish shell by a snap fastener, and the fish shell is connected to the main frame by bolts.

[0020] As a preferred technical solution of this application, the fish body is also equipped with an infrared sensor for real-time monitoring of the surrounding environment and identification of the water-land boundary.

[0021] The amphibious biomimetic robotic fish provided by this invention has the following beneficial effects:

[0022] 1. Compact and efficient structure: The linkage-type multi-leg structure is integrated into the fish body, eliminating the need for external additional moving modules, reducing water resistance, reducing failure points, significantly reducing manufacturing costs and overall weight, and improving land mobility.

[0023] 2. Reliable mode switching: Through the hatch structure and the internally integrated multi-legged structure, the amphibious mode can be quickly switched without the need for a complex deformation mechanism, reducing the switching failure rate; the multi-legged structure and electronic components are placed together in the main frame, optimizing the space layout.

[0024] 3. Strong stability: The quadruped module adopts a double crank 180° phase difference design, combined with four independent power sources, which improves the stability of walking on land and can achieve flexible turning through differential speed; the passive swing design of the tail fin and the posture adjustment function of the pectoral fin ensure the flexibility of underwater movement.

[0025] In addition to the purposes, features, and advantages described above, this application has other purposes, features, and advantages. A further detailed description of this application will be provided below with reference to the figures. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0027] Figure 1 This is an overall view of the hatch of the present invention when closed;

[0028] Figure 2 This is an overall view of the hatch opening mechanism of the present invention;

[0029] Figure 3 This is a diagram of the internal structure of the present invention;

[0030] Figure 4 This is a structural diagram of the main framework of the present invention;

[0031] Figure 5 This is a diagram of the linkage-type four-legged structure of the present invention;

[0032] Figure 6 This is a top view of the four-legged transmission structure of the present invention;

[0033] Figure 7 This is a cross-sectional view of the four-legged transmission structure of the present invention;

[0034] Figure 8 This is a cross-sectional view of the four-legged transmission structure of the present invention;

[0035] Figure 9 This is a diagram of the pectoral fin drive structure of the present invention;

[0036] Figure 10 This is a diagram of the linkage-type multi-leg structure of the present invention;

[0037] Figure 11 This is a diagram of the tail fin drive structure of the present invention.

[0038] Reference numerals: 1. Fish head; 2. Infrared sensor; 3. Door; 4. Dorsal fin; 5. Fish body; 6. Caudal fin; 7. Pectoral fin; 8. Fish tail; 9. Waterproof control compartment; 10. Linkage-type multi-leg structure; 11. Door connecting block; 12. Main frame; 13. Switch; 14. Charging interface; 15. Wireless communication module; 16. Waterproof tail fin drive servo; 17. Tail fin transmission bracket; 18. Tension spring; 19. Waterproof lithium battery compartment; 20. Fish body shell; 21. Waterproof door drive servo; 22. Small disc; 23. Gear one; 24. Gear two; 25. Support frame;

[0039] 26. Door drive shaft; 27. Bearing 1; 28. Lower leg rod; 29. ​​Connecting rod; 30. Upper leg rod; 31. Rocker arm; 32. Crank; 33. Frame; 34. Spur gear 1; 35. Crank drive shaft; 36. Bevel gear 1; 37. Spur gear 2; 38. Bevel gear 2; 39. Waterproof housing; 40. Reducer; 41. Quadruped module drive motor; 42. Connecting disc; 43. Connecting bracket; 44. Tail fin connecting block; 45. Pectoral fin waterproof drive servo; 46. Pectoral fin drive shaft; 47. Bearing 2; 48. Pectoral fin fastener; 49. Drive shaft; 50. Gear 3; 51. Gear 4; 52. Connecting column. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] like Figures 1-11 As shown, the amphibious biomimetic robotic fish of the present invention includes a fish head 1, a fish body 5, a fish tail 8, a dorsal fin 4, a fish shell 20, and an internal main frame 12; it also includes: a linkage-type multi-leg structure 10, a hatch structure, a tail fin drive structure, a pectoral fin drive structure, and a waterproof control chamber 9, a waterproof lithium battery chamber 19, a switch 13, a charging interface 14, and a wireless communication module 15 integrated on the main frame 12. The present invention can achieve long-distance control via wireless remote control, and the infrared sensor can achieve obstacle avoidance function.

[0042] The linkage-type multi-legged structure 10 consists of four four-legged modules, each of which includes a transmission structure and a crank-rocker structure. The crank-rocker structure consists of a lower leg 28, a connecting rod 29, a upper leg 30, a rocker arm 31, a crank 32, and a frame 33 forming a single leg. Two single legs are symmetrically placed and share a crank to form a crank-rocker structure. Two crank-rocker structures are symmetrically placed to form a four-legged module.

[0043] Each quadruped module is driven by an independent power source, which includes a quadruped module drive motor 41 and a reducer 40. The output end of the reducer 40 is connected to a second bevel gear 38 via a key. The second bevel gear 38 meshes with a first bevel gear 36. The first bevel gear 36 and a second spur gear 37 are connected to a drive shaft 49 via a key. The second spur gear 37 meshes with a first spur gear 34. The first spur gear 34 is mounted on a crank drive shaft 35 to transmit power to the crank, thereby realizing the movement of the quadruped module.

[0044] Two cranks 32 are mounted on the same crank drive shaft 35 and have a 180° phase difference to ensure walking stability. The entire multi-legged structure is driven by four independent power sources to achieve land walking function, and can achieve turning function by the speed difference between the inner and outer legs. The entire linkage multi-legged structure is connected to the main frame 12 by connecting brackets 43 bolts.

[0045] like Figure 4 As shown, the hatch structure includes a hatch 3, a waterproof drive servo motor 21, a gear transmission assembly (50, 23, 24, 51), a hatch drive shaft 26, and a hatch connecting block 11. The waterproof drive servo motor 21 is connected to the main frame 12 via a bracket. Its power is transmitted to the hatch drive shaft 26 via a small disc 22, output gear 3 50, and gears 1 23, 2 24, and 4 51. The hatch drive shaft 26 is mounted on a support frame 25 via bearing 1 27. The support frame 25 is bolted to the main frame 12. The hatch 3 is connected to the hatch drive shaft 26 via the hatch connecting block 11, thereby enabling the hatch 3 to open and close. When the hatch is open, the internal linkage-type multi-legged structure 10 is exposed for land walking; when the hatch is closed, the fish-shaped body is streamlined for underwater movement. It can adapt to cross-media operations in various scenarios such as mudflats, shallow seas, and shorelines.

[0046] like Figure 3 , Figure 11 As shown, the tail fin drive structure includes a waterproof tail fin drive servo 16, a tail fin transmission bracket 17, a tension spring 18, and a tail fin connecting block 44. The waterproof tail fin drive servo 16 is fixed on the main frame 12, and its output end is connected to the tail fin transmission bracket 17 through a connecting disc 42. The tail fin 6 is mounted on the main frame 12 through the tail fin connecting block 44. One end of the tension spring 18 is connected to the connecting post 52 of the tail fin transmission bracket 17, and the other end is connected to the tail fin connecting block 44, so that the tail fin 6 and the tail fin transmission bracket 17 are non-rigidly connected.

[0047] The tail fin drive servo 16 drives the tail fin 6 to swing, achieving underwater movement. Since the tail fin 6 and the tail fin drive bracket 17 are not rigidly connected, the tension spring 18 allows the tail fin 6 to passively swing when it encounters resistance in the water during the swinging process of the tail fin drive bracket. The differential speed of the tail fin waterproof drive servo enables the turning function of the robotic fish.

[0048] like Figure 9 As shown, the pectoral fin drive structure includes a waterproof pectoral fin drive servo 45, a pectoral fin drive shaft 46, a second bearing 47, and a pectoral fin fastener 48. The waterproof pectoral fin drive servo 45 is mounted on the hatch 3, and its power is transmitted to the pectoral fin 7 through the pectoral fin drive shaft 46. The second bearing 47 is mounted on the pectoral fin drive shaft 46. The robotic fish can adjust its posture in the water with the assistance of the pectoral fin drive.

[0049] Core protection points and technological value: The key protection point is the collaborative design of "internal integrated linkage multi-leg structure + hatch switching mechanism"; its technological value lies in breaking through the industry bottleneck of "structural redundancy" and "movement efficiency contradiction" in amphibious robots, realizing lightweight, highly reliable and low-cost cross-media movement, and providing more practical equipment solutions for underwater exploration, environmental monitoring and other fields.

[0050] The working principle and process of the amphibious bionic robotic fish of this invention are briefly described below.

[0051] In the initial standby state, hatch 3 is closed, and the robotic fish is streamlined. Electronic components such as the waterproof control compartment 9 and the waterproof lithium battery compartment 19 operate at low power, while the infrared sensor 2 monitors the surrounding environment in real time.

[0052] When the robotic fish needs to perform an underwater task, it initiates an underwater operation command. For example... Figure 11 As shown, the waterproof tail fin drive servo 16 drives the tail fin transmission bracket 17 to swing. Due to the non-rigid connection of the tension spring 18, the tail fin 6 can achieve passive buffering swing when it encounters resistance in the water, generating efficient propulsion. By controlling the differential speed of the waterproof tail fin drive servo 16, the robotic fish can turn. Simultaneously, as... Figure 9 As shown, the waterproof drive servo motor 45 of the pectoral fin can drive the pectoral fin 7 to rotate, assist in adjusting the underwater attitude, ensure stable movement, and complete tasks such as underwater detection and path navigation.

[0053] When the robotic fish detects land environments such as shorelines or mudflats via infrared sensor 2, its tail fin 6 and pectoral fin 7 cease movement, and the robotic fish slowly approaches the land and stabilizes its posture. Then, as... Figure 4 As shown, the hatch waterproof drive servo 21 is activated, driving the hatch drive shaft 26 to rotate via gear set (50, 23, 24, 51), thereby opening the hatch 3 and revealing the internally integrated linkage-type multi-leg structure 10, as shown. Figure 2 As shown.

[0054] Next, the robotic fish switched to land-based movement mode. For example... Figure 5 , Figure 6 , Figure 7As shown, four quadruped modules drive motors 41, which are transmitted via reducer 40, bevel gear 2 38, bevel gear 1 36, spur gear 2 37, and spur gear 1 34, thereby rotating the crank drive shaft 35. Due to the 180° phase difference between the two cranks 32 on the same shaft, stable crank-rocker-style walking motion can be achieved. The coordinated movement of the four modules propels the robotic fish forward. By adjusting the speed difference between the inner and outer quadruped module drive motors 41, actions such as turning on land and overcoming obstacles can be achieved, completing cross-medium movement.

[0055] Upon completion of land-based operations or when returning to the water, the robotic fish again uses infrared sensor 2 to determine the direction of the water area and approaches the water's edge in land-based movement mode. Subsequently, the waterproof drive servo 21 of the hatch reverses its direction, closing the hatch 3 and retracting the linkage-type multi-legged structure 10 into the fish's body. The robotic fish then switches back to underwater movement mode and autonomously returns to the designated location. After the mission is completed, it can receive a shutdown command via wireless communication module 15 to enter standby mode, or replenish its power via charging interface 14.

[0056] This invention overcomes the structural bulkiness problem caused by combining a pure robotic fish with external auxiliary modules; it also overcomes the problems of low underwater propulsion efficiency, high failure rate during motion mode switching, and unreasonable internal space layout caused by multi-legged robots with watertight shells; and it overcomes the problems of low system reliability, poor motion continuity, and limited endurance caused by deformable structure designs. This invention achieves high efficiency, reliability, and compactness in amphibious functionality through an internally integrated linkage-type multi-legged structure design.

[0057] The amphibious biomimetic robotic fish of the present invention also overcomes the problems of low underwater propulsion efficiency, high failure rate of motion mode switching and unreasonable internal space layout caused by multi-legged robots with watertight shells. It provides a robotic fish with an internally integrated multi-legged structure, which significantly improves underwater propulsion efficiency, makes the motion mode switching process more reliable, and optimizes the internal space layout to achieve efficient integration of electronic components and power system.

[0058] The amphibious bionic robotic fish of the present invention also overcomes the problems of low system reliability, poor motion continuity and limited endurance caused by deformable structure schemes, and provides an amphibious robotic fish that does not require a complex deformation mechanism, so as to improve the overall system reliability, ensure the continuity of water and land movement and extend the endurance of the device.

[0059] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An amphibious biomimetic robotic fish, characterized in that, Including the fish body, main frame (12), caudal fin drive structure and pectoral fin drive structure, and also including: A linkage-type multi-legged structure (10) is integrated inside the fish body for walking on land; The hatch structure includes a hatch (3) and a hatch drive mechanism. The hatch drive mechanism drives the hatch (3) to open or close. When the hatch (3) is open, the linkage multi-leg structure (10) is exposed. When the hatch (3) is closed, the fish body forms a streamlined shape.

2. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The linkage-type multi-leg structure (10) consists of four quadruped modules, each quadruped module including a transmission structure and a crank-rocker structure; the crank-rocker structure consists of a lower leg rod (28), a connecting rod (29), a upper leg rod (30), a rocker arm (31), a crank (32) and a frame (33) forming a single leg, two single legs are symmetrically placed and share a crank (32) to form a crank-rocker structure, and two crank-rocker structures are symmetrically placed to form the quadruped module.

3. The amphibious biomimetic robotic fish according to claim 2, characterized in that, Each of the four-legged modules is driven by an independent power source, which includes a four-legged module drive motor (41) and a reducer (40). The output end of the reducer (40) is connected to a bevel gear two (38) via a key. The bevel gear two (38) meshes with a bevel gear one (36). The bevel gear one (36) and a spur gear two (37) are connected to a drive shaft (49) via a key. The spur gear two (37) meshes with a spur gear one (34). The spur gear one (34) is mounted on a crank drive shaft (35) to transmit power to the crank (32).

4. The amphibious biomimetic robotic fish according to claim 3, characterized in that, Two of the cranks (32) in each of the four-legged modules are mounted on the same crank drive shaft (35) and have a phase difference of 180°; the robotic fish can turn on land by adjusting the speed difference of the independent power sources of the four four-legged modules.

5. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The hatch drive mechanism includes a hatch waterproof drive servo (21) and a gear transmission group. The gear transmission group includes output gear three (50), gear one (23), gear two (24) and gear four (51). The hatch waterproof drive servo (21) is connected to the main frame (12) by a bracket. Its output end is connected to output gear three (50) through a small disc (22). Output gear three (50) meshes with gear one (23). Gear one (23), gear two (24) and gear four (51) are mounted on the hatch drive shaft (26). The hatch (3) is connected to the hatch drive shaft (26) through a hatch connecting block (11).

6. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The tail fin drive structure includes a waterproof tail fin drive servo (16), a tail fin transmission bracket (17), a tension spring (18), and a tail fin connecting block (44). The waterproof tail fin drive servo (16) is fixed on the main frame (12), and its output end is connected to the tail fin transmission bracket (17) through a connecting disc (42). The tail fin (6) is mounted on the main frame (12) through the tail fin connecting block (44). One end of the tension spring (18) is connected to the connecting post (52) of the tail fin transmission bracket (17), and the other end is connected to the tail fin connecting block (44), so that the tail fin (6) and the tail fin transmission bracket (17) form a non-rigid connection to achieve passive oscillation. The robot fish turns underwater through the differential control of the waterproof tail fin drive servo (16).

7. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The pectoral fin drive structure includes a pectoral fin waterproof drive servo (45), a pectoral fin drive shaft (46), a bearing (47), and a pectoral fin fastener (48). The pectoral fin waterproof drive servo (45) is installed on the hatch (3), and its power is transmitted to the pectoral fin (7) through the pectoral fin drive shaft (46). The bearing (47) is installed on the pectoral fin drive shaft (46).

8. The amphibious biomimetic robotic fish according to claim 1, characterized in that, It also includes a waterproof control compartment (9), a waterproof lithium battery compartment (19), a switch (13), a charging interface (14), and a wireless communication module (15) integrated on the main frame (12).

9. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The fish body includes a head (1), a body (5), a tail (8), a dorsal fin (4), and a shell (20). The dorsal fin (4) is attached to the shell (20) by a snap fastener, and the shell (20) is connected to the main frame (12) by bolts.

10. The amphibious biomimetic robotic fish according to claim 1, characterized in that, The fish is also equipped with an infrared sensor (2) for real-time monitoring of the surrounding environment and identification of the water-land boundary.

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