Adsorption type bionic robotic fish

Abstract

The invention relates to the technical field of underwater robots, and provides an adsorption type bionic robotic fish which comprises an adsorption assembly and a bionic robotic fish body, and the adsorption assembly is installed on the bionic robotic fish body; the adsorption assembly comprises a negative pressure pump, a control mainboard and a plurality of adsorption modules, and the adsorption modules are connected with the negative pressure pump; wherein each adsorption module comprises a suction cup, an adsorption channel, a desorption channel, a first electromagnetic valve and a second electromagnetic valve, the suction cup is in fluid communication with the negative pressure pump through the adsorption channel, the desorption channel is in fluid communication with the adsorption channel, the first electromagnetic valve is installed on the adsorption channel, and the second electromagnetic valve is installed on the desorption channel; the negative pressure pump, the first electromagnetic valve and the second electromagnetic valve are all electrically connected with the control main board. The adsorption type bionic robotic fish can be stably attached to the surface of an adsorption object in the underwater environment, the adsorption force is strong enough, and the adsorption type bionic robotic fish cannot fall off easily even under the condition of large water flow. Meanwhile, the adsorption and desorption operation response is rapid, and the requirement of real-time monitoring can be met.

Description

Technical Field

[0001] The invention relates to the technical field of underwater robots, and in particular to an adsorption-type bionic robot fish. Background Art

[0002] In recent years, underwater robots have played an increasingly important role in the exploration and development of the ocean. As a special underwater robot, the bionic robot fish has gradually received widespread attention and application. The bionic robot fish is a product of the combination of robotics and bionics. Thanks to its fish-like swimming, compared with traditional propeller-propelled underwater robots, the bionic robot fish has the advantages of good maneuverability, low energy consumption, low disturbance and high concealment. Therefore, the bionic robot fish has broad application prospects in various fields.

[0003] At present, the existing bionic robot fish has certain perception ability and good control performance, but there are still problems such as insufficient motion performance, low sensor accuracy, and limited operation scenes, which cannot cope with complex and changeable underwater operation scenes and diversified underwater operation tasks. In nature, fish can rely on their unique suction cup structure to adhere to the surface of the host, so as to greatly reduce their own energy consumption during ocean voyages. In addition, fish can also quickly adjust their posture while swimming in the water, and can achieve high-maneuverability movement even in narrow waters, and quickly adhere to the surface of the host.

[0004] However, existing bionic robot fish mainly rely on tail fin drive, which not only makes it difficult to achieve good swimming performance, but also lacks the ability of autonomous adsorption, making it difficult to truly imitate the movement characteristics of biological fish and has the problem of poor movement flexibility. Summary of the invention

[0005] The present invention provides an adsorption-type bionic robot fish, which is used to realistically imitate the movement characteristics of biological fish, realize complex underwater tasks such as underwater adsorption, and solve the problem of poor movement flexibility of existing bionic robot fish.

[0006] The present invention provides an adsorption-type bionic robot fish, comprising: an adsorption component and a bionic robot fish body, wherein the adsorption component is installed on the bionic robot fish body; The adsorption assembly includes a negative pressure pump, a control mainboard and multiple adsorption modules, and the multiple adsorption modules are all connected to the negative pressure pump; wherein each of the adsorption modules includes a suction cup, an adsorption channel, a desorption channel, a first solenoid valve and a second solenoid valve, the suction cup is fluidically connected to the negative pressure pump through the adsorption channel, the desorption channel is fluidically connected to the adsorption channel, the first solenoid valve is installed in the adsorption channel, the second solenoid valve is installed in the desorption channel, and the negative pressure pump, the first solenoid valve and the second solenoid valve are all electrically connected to the control mainboard.

[0007] According to the adsorption-type bionic robotic fish provided by the present invention, the Shore hardness of the suction cup is 25A-35A; and / or, The inclination angle of the suction cup is 15°~45°.

[0008] According to a suction-type bionic robotic fish provided by the present invention, the suction component also includes a distance sensor, which is installed on the bionic robotic fish body and located between two adjacent suction cups; wherein the negative pressure pump, the distance sensor, the first solenoid valve and the second solenoid valve are all electrically connected to the control main board, and the control main board is configured to control the opening of the negative pressure pump and the corresponding first solenoid valve according to the distance value of the distance sensor.

[0009] According to an adsorption-type bionic robotic fish provided by the present invention, each of the adsorption modules also includes a pressure sensor, which is installed in the adsorption channel and is used to obtain the pressure value in the adsorption channel. The pressure sensor is electrically connected to the control main board, and the control main board is also configured to control the action of the negative pressure pump and the corresponding first solenoid valve according to the pressure value of the pressure sensor, so that the pressure value is equal to the target pressure value.

[0010] According to the adsorption-type bionic robotic fish provided by the present invention, the plurality of suction cups corresponding to the plurality of adsorption modules are sequentially spaced apart along the length direction of the bionic robotic fish body.

[0011] According to the adsorption-type bionic robotic fish provided by the present invention, the bionic robotic fish body comprises a cabin section, a fish tail and a tail fin, and the cabin section, the fish tail and the tail fin are connected in sequence; The adsorption-type bionic robotic fish also includes a pectoral fin assembly, which includes a first drive assembly, a first pectoral fin and a second pectoral fin, wherein the first drive assembly is disposed in the cabin section, the first pectoral fin and the second pectoral fin are relatively disposed on the left and right sides of the cabin section, and the first drive assembly is respectively connected to the first pectoral fin and the second pectoral fin; wherein the first drive assembly is used to adjust the inclination angle of the first pectoral fin and the second pectoral fin relative to the horizontal plane, and to drive the first pectoral fin and the second pectoral fin to swing up and down relative to the cabin section.

[0012] According to a suction-type bionic robotic fish provided by the present invention, the suction-type bionic robotic fish also includes a fishtail drive assembly, and the fishtail drive assembly includes multiple drive joints, and the multiple drive joints are connected in series in sequence along the extension direction of the fishtail, one of the multiple drive joints close to the cabin section is connected to the cabin section, and one of the multiple drive joints far from the cabin section is connected to the tail fin.

[0013] According to the adsorption-type bionic robotic fish provided by the present invention, the adsorption-type bionic robotic fish also includes a sensor component, and the sensor component, the pectoral fin component and the fishtail drive component are all electrically connected to the control mainboard.

[0014] According to the adsorption-type bionic robotic fish provided by the present invention, the sensing component includes at least one of a visual module, a depth sensor and an inertial measurement unit.

[0015] According to an adsorption-type bionic robotic fish provided by the present invention, the adsorption-type bionic robotic fish also includes a battery assembly, and the battery assembly is arranged in the bionic robotic fish body. The bionic robotic fish body is provided with a charging port, at least part of the charging port is exposed on the surface of the bionic robotic fish body, and the charging port and the battery assembly are electrically connected.

[0016] The adsorption-type bionic robotic fish provided by the present invention can stably adhere to the surface of the adsorption object in an underwater environment, and the adsorption force is strong enough that it will not fall off easily even in the case of a large water flow. At the same time, the adsorption and desorption operations respond quickly, which can meet the needs of real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or 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 work.

[0018] Figure 1 This is one of the structural schematic diagrams of the adsorption-type bionic robotic fish provided by the present invention.

[0019] Figure 2 This is the second structural schematic diagram of the adsorption-type bionic robotic fish provided by the present invention.

[0020] Figure 3 It is a structural schematic diagram of the adsorption component provided by the present invention.

[0021] Figure 4 It is a structural schematic diagram of the suction cup provided by the present invention.

[0022] Figure 5 It is a schematic structural diagram of the pectoral fin assembly provided by the present invention.

[0023] Figure 6 It is a structural schematic diagram of the fishtail drive assembly provided by the present invention.

[0024] Figure 7 This is a suction cup cycle adsorption test diagram provided by the present invention.

[0025] Figure 8 This is a suction cup preload force test diagram provided by the present invention.

[0026] Fig. 9 This is a test diagram of the maximum adsorption force of the suction cup provided by the present invention.

[0027] Fig.10 This is a test diagram of the steady-state adsorption force of the suction cup provided by the present invention.

[0028] Fig.11 It is a pressure timing diagram of the adsorption and desorption process under the maximum adsorption force provided by the present invention.

[0029] Fig.12 It is a pressure timing diagram of the adsorption object under the change of the tilt angle provided by the present invention.

[0030] Fig.13 It is a desorption time diagram under the change of adsorption object radius provided by the present invention.

[0031] Fig.14 It is a desorption time diagram under the change of roughness of the adsorption object provided by the present invention.

[0032] Reference numerals: 1. Bionic robot fish body; 11. Cabin section; 12. Fish tail; 13. Tail fin; 2. Adsorption component; 21. Negative pressure pump; 22. Adsorption module; 221. Suction cup; 222. Adsorption channel; 223. Desorption channel; 224. First solenoid valve; 225. Second solenoid valve; 226. Pressure sensor; 23. Distance sensor; 3. Pectoral fin component; 31. First pectoral fin; 32. Second pectoral fin; 4. Fish tail drive component; 5. Visual module. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Combine the following Figure 1-Figure 14 The adsorption-type bionic robotic fish of the present invention is described.

[0035] like Figure 1 , Figure 2 and Figure 3 As shown, the adsorption-type bionic robotic fish according to the embodiment of the present invention comprises: an adsorption component 2 and a bionic robotic fish body 1 , wherein the adsorption component 2 is installed on the bionic robotic fish body 1 .

[0036] The adsorption assembly 2 includes a negative pressure pump 21, a control main board and multiple adsorption modules 22, and the multiple adsorption modules 22 are all connected to the negative pressure pump 21; wherein each adsorption module 22 includes a suction cup 221, an adsorption channel 222, a desorption channel 223, a first solenoid valve 224 and a second solenoid valve 225, the suction cup 221 is fluidically connected to the negative pressure pump 21 through the adsorption channel 222, the desorption channel 223 is fluidically connected to the adsorption channel 222, the first solenoid valve 224 is installed in the adsorption channel 222, the second solenoid valve 225 is installed in the desorption channel 223, and the negative pressure pump 21, the first solenoid valve 224 and the second solenoid valve 225 are all electrically connected to the control main board.

[0037] It should be noted that the bionic robot fish body 1 can adopt a streamlined design to imitate the appearance of a real fish, and the shell is made of high-strength plastic material 3D printing. A power system is installed inside to drive the robot fish to swim in the water. At the same time, it is equipped with a positioning system and a communication system to facilitate data transmission and positioning tracking with the outside world.

[0038] The negative pressure pump 21 may be a diaphragm pump installed inside the bionic robot fish body 1. The negative pressure pump 21 has sufficient suction force to meet the requirements of multiple adsorption modules 22 working simultaneously. The control mainboard may use a high-performance single-chip microcomputer as the control mainboard, which is installed in a waterproof sealed box inside the robot fish. The control mainboard integrates a microprocessor, a power management module, a communication interface, etc., and is used to control the working states of the negative pressure pump 21, the first solenoid valve 224, and the second solenoid valve 225.

[0039] In addition, the number of adsorption modules 22 can be multiple, for example, a total of 4 adsorption modules 22 are installed, evenly distributed on the top of the bionic robot fish body 1. The specific structure of each adsorption module 22 is as follows: A suction cup 221 made of flexible silicone material is selected, which has good adsorption performance and sealing performance. Corrosion-resistant plastic pipes are used as adsorption channels 222 and desorption channels 223. The adsorption channel 222 connects the suction cup 221 to the negative pressure pump 21, and the desorption channel 223 is connected to the adsorption channel 222. Small, low-power electromagnetic valves are selected and installed on the adsorption channel 222 and the desorption channel 223 respectively. These two solenoid valves can quickly respond to the instructions of the control motherboard to achieve precise control of the adsorption and desorption operations.

[0040] Specifically, after starting the negative pressure pump 21, the first solenoid valve 224 is opened, and the negative pressure pump 21 is fully pressurized. At the same time, water is quickly discharged from the suction cup 221 to the bottom of the fish body along the adsorption channel 222. Taking into account the net buoyancy of the adsorption-type bionic robot fish, a sealed internal environment is established through the Bernoulli principle and the recoil force of water. Subsequently, the negative pressure pump 21 draws water out of the sealed cavity to make the internal pressure lower than the external environment. Therefore, the suction cup 221 is tightly adsorbed on the surface of the adsorption object under the action of water pressure. During the desorption process, the first solenoid valve 224 is closed, the second solenoid valve 225 is opened, and the desorption channel 223 balances the internal and external pressure differences. In this way, the reversibility of the adsorption process is effectively ensured while maintaining a low preload requirement.

[0041] Through actual tests, the adsorption-type bionic robot fish can stably adhere to the surface of the adsorption object in an underwater environment, and the adsorption force is strong enough that it will not fall off easily even in a large water flow. At the same time, the adsorption and desorption operations respond quickly and can meet the needs of real-time monitoring. In addition, the appearance and swimming style of the bionic robot fish are similar to those of real fish, and will not cause obvious interference to the normal life of underwater creatures, providing an effective monitoring method for marine scientific research.

[0042] The suction cup 221 is made of addition-type AB component silicone and is arranged on the back of the bionic robot fish. The specific steps of manufacturing the suction cup 221 are as follows: (1) Mix and stir the AB component silicone in a ratio of 1:1; (2) Remove the bubbles in the silicone; (3) Pour the silicone into the 3D printed mold, and demold it after curing at room temperature for 3-4 hours. The suction cup 221 has a diameter of 35 mm and a mass of 2.6 g.

[0043] In an optional embodiment, if Figure 4 As shown, the inclination angle of the suction cup 221 is 15° to 45°. Exemplarily, the inclination angle of the suction cup 221 is 15°, 20°, 25°, 30°, 35°, 40°, 45°. The Shore hardness of the suction cup 221 is 25A to 35A. Exemplarily, the Shore hardness of the suction cup 221 is 25A, 30A, 35A.

[0044] It should be noted that, under a specific pressure difference, the area of ​​the adsorption region has a significant effect on the adsorption force. In order to explore this relationship, the influence of the shape and material of the suction cup 221 on the area of ​​the adsorption region is considered, and two factors are introduced: manufacturing angle and Shore hardness.

[0045] Specifically, after a stable adsorption is established between the suction cup 221 and the adsorption object, a force is applied to the suction cup 221 along the guide rail until detachment occurs, and during the experiment, a force sensor is used to record the applied force. In order to improve observability, a transparent acrylic plate is used as the adsorption target. Fig. 9 , Fig.10 as well as Fig.11 Nine parameter combinations of the suction cup 221 are presented, using three different manufacturing angles (15°, 30°, 45°) and three hardnesses (25 A, 30 A, 35 A).

[0046] During the experimental verification process, the solenoid valve channel is first opened, and then the diaphragm pump is fully started to provide negative pressure for 20 seconds to ensure firm adsorption. After establishing firm adsorption, the corresponding channel is sealed and the performance index is measured by slowly lifting the force measuring device. Fig. 9 , Fig.10 The maximum adsorption force and the steady-state adsorption force are shown respectively. The steady-state adsorption force is defined as the force that can maintain adsorption for more than one minute, reflecting the strength and stability of the adsorption. As the hardness of the suction cup 221 increases, the suction cup 221 exhibits greater rigidity and is not easily deformed under the action of negative pressure, which helps to form an effective seal on the plane. In addition, for planar adsorption targets, due to the miniaturization and flexibility of the suction cup 221, changes in the manufacturing angle have little effect on the diameter of the suction cup 221, but have a greater impact on the supporting force provided by the material. Therefore, as the manufacturing angle of the suction cup 221 decreases, it obtains more supporting force and reduces deformation under negative pressure. Ultimately, these two improvements ensure better sealing and more uniform force distribution, enabling stronger adsorption force and longer adsorption time.

[0047] In addition, a curved acrylic plate was used as an adsorption target. After establishing reliable adsorption, the target was slowly lifted, the pressure change during the desorption process was recorded, and the pressure during stable adsorption was compared. At the same 30° manufacturing angle, the high-hardness suction cup 221 showed a greater internal negative pressure change during the desorption process. In contrast, the softer suction cup 221, due to its more flexible material, will deform significantly when negative pressure is generated, thereby maintaining a better fit with the target surface during the detachment process, resulting in a smaller pressure change. In addition, for the suction cup 221 with a hardness of 35 A, the negative pressure fluctuations during the desorption process are always large. It is worth noting that the suction cup 221 with a manufacturing angle of 30° showed the most obvious negative pressure change. This obvious change may be due to the 30° manufacturing angle providing the best support, allowing the suction cup 221 to enhance the structural support while maintaining sufficient flow channels, thereby achieving an excellent balance between rigidity and fluidity.

[0048] Finally, the suction cup 221 with a hardness of 35 A was integrated into the bionic robotic fish platform. After the suction cup 221 established adsorption, it could maintain reliable adsorption even under the disturbance caused by the propeller, and pushed the robotic dolphin and the robotic remora about 2 meters in 15 seconds. This shows that the suction cup 221 designed by the present invention has high stability and reliability in practical applications and can effectively cope with dynamic environments.

[0049] In an unstructured environment, it is particularly important to enhance the adaptability of the suction cup 221 to adsorption targets of irregular shapes and non-ideal angles. Therefore, the present invention verifies the adaptability and perception ability of the proposed adsorption system by adjusting the tilt angle, radius and roughness of the target surface.

[0050] like Fig.12 , Fig.13 and Fig.14 The tilt angles of the adsorbed objects varied from 0° to 7.5° in 2.5° increments. The radii tested included R=38.20 mm (syringe), R=62.00 mm (paint cover), R=83.90 mm (curved acrylic plate), and R= (Flat acrylic). Roughness levels include Ra=3.9 and Ra=48.2 The experiments conducted in the present invention all used a set of suction cups 221 with a hardness of 35 A, all the experiments were conducted under zero preload, and each set of experiments was repeated 5 times.

[0051] In addition, the introduction of multi-channel independent control of the adsorption component 2 in the present invention, coupled with the miniaturization and flexibility of the suction cup 221, effectively copes with the change of the radius of the target surface. Under the steady-state adsorption force, the present invention changes the manufacturing angle of the suction cup 221 and measures the desorption time of adsorption objects with different radii. The results show that as the manufacturing angle of the suction cup 221 increases, especially at 45°, the suction cup 221 has a greater impact on the R (38.20 mm, ) shows stronger adaptability to radius changes within the range of 2° and 1°, and can maintain adsorption for more than 1 minute under the action of steady-state adsorption force. On the contrary, at 15°, as the radius of the adsorption target increases, it is difficult for the suction cup 221 to maintain the initial steady-state force, and it performs poorly even at a lower steady-state adsorption force. Experiments carried out by the present invention show that when the target radius varies greatly, a smaller manufacturing angle can generally provide a stronger supporting force, so that the suction cup 221 has a stronger adsorption force and higher rigidity. This rigidity hinders the flexible adjustment and bending of the edge of the suction cup 221, limits the edge adaptability, and cannot effectively cover and adapt to the curved surface, making it difficult to form an effective seal. In short, due to the limited adaptability of the suction cup 221, it is challenging to achieve tight adsorption and establish a vacuum environment on a highly curved surface. Therefore, the multi-channel suction cup 221 array proposed in the present invention can improve the overall adaptability of the system. In addition, the independent control of multiple channels can ensure the reliability of adsorption.

[0052] The present invention also studies the influence of the manufacturing angle of the suction cup 221 by testing adsorption on surfaces with different roughness. Steady-state adsorption force was applied to surfaces with roughness values ​​of 3.9 and 48.2. As the roughness increases, the adsorption performance of the suction cup 221 with a smaller manufacturing angle decreases more slowly. This is because a smaller contact area is conducive to maintaining a sealed environment on a rough surface. Therefore, the suction cup 221 with a manufacturing angle of 30° has better overall performance in balancing channel diameter and supporting force. In addition, for Wenext 7200 nylon glass fiber material, due to its high roughness, the negative pressure pump 21 needs to be continuously started to maintain adsorption. At manufacturing angles of 15°, 30° and 45°, the desorption times are 0.2 min, 0.56 min and 0.30 min, respectively.

[0053] In actual application, multiple suction cups 221 corresponding to multiple suction modules 22 are arranged in sequence along the length direction of the bionic robot fish body 1. The suction component 2 also includes a distance sensor 23, which is installed on the bionic robot fish body 1 and is located between two adjacent suction cups 221; wherein the negative pressure pump 21, the distance sensor 23, the first solenoid valve 224 and the second solenoid valve 225 are all electrically connected to the control mainboard, and the control mainboard is configured to control the opening of the negative pressure pump 21 and the corresponding first solenoid valve 224 according to the distance value of the distance sensor 23. In this way, a multi-channel suction cup 221 is integrated, and each suction cup 221 can be independently controlled. Using a diaphragm pump, active and reliable underwater suction is formed by generating negative pressure.

[0054] Each adsorption module 22 also includes a pressure sensor 226, which is installed in the adsorption channel 222 and is used to obtain the pressure value in the adsorption channel 222. The pressure sensor 226 is electrically connected to the control main board, and the control main board is also configured to control the action of the negative pressure pump 21 and the corresponding first solenoid valve 224 according to the pressure value of the pressure sensor 226, so that the pressure value is equal to the target pressure value.

[0055] It is understandable that in order to enhance the perception ability, the suction cup 221 is also embedded with multiple sensor arrays. The pressure sensor 226 group is connected to each channel of the suction cup 221 array to feedback the adsorption status; the distance sensor 23 array is installed in the waterproof cabin next to each channel of the suction cup 221 array, so that the robot fish can determine the shape and relative position of the approaching target. The negative pressure pump 21 can create negative pressure for different channels according to the feedback of the sensor.

[0056] The adsorption workflow is as follows: before adsorption, the robot fish determines the shape and relative position of the target through the distance sensor 23 array. Subsequently, it controls the negative pressure pump 21 to perform the adsorption process through a fuzzy control method based on a finite state machine. In addition, considering that the micro-diaphragm pump cannot generate positive pressure, desorption is achieved by destroying the sealed environment through another balance channel (desorption channel 223).

[0057] Considering the motion characteristics of the robotic fish platform and the specific requirements of the adsorption task, five key indicators are introduced to quantitatively evaluate the proposed adsorption component 2 and improve the structural parameters of the suction cup 221. These indicators include basic adsorption characteristics (reversible adsorption, preload), adsorption adaptability, adsorption strength and perception ability.

[0058] Reversibility requires that the suction cup 221 change little between each adsorption cycle to maintain consistency, and at the same time have sufficient durability to ensure stable and reliable performance during multiple uses. Therefore, the present invention performs a complete adsorption and desorption task in a cycle to verify reversibility. Specifically: (1) The critical state where the suction cup 221 just touches the target surface is set as the starting point of the task; (2) The solenoid valve channel is opened and the diaphragm pump is fully started for 10 seconds to ensure firm adsorption; (3) After maintaining the adsorption state for 5 seconds, the balance channel is opened to balance the pressure difference and complete the desorption process; (4) Figure 7 A cycle including 10 adsorption and desorption processes is shown, and the pressure change during a single adsorption and desorption process is also shown. After completing a cycle, the task is reset to the starting point and repeated 5 times. Taking the negative pressure formed during the first adsorption and desorption process as the standard value, the minimum value of the standardized pressure during the cycle test is 0.996 and the maximum value is 1.024. The difference in adsorption force of the adsorption component 2 developed by the present invention during multiple cycles is extremely small, which shows that the system has excellent reversibility and can maintain stable performance during repeated use, ensuring the consistency and reliability of each adsorption and desorption.

[0059] In order to make the adsorption component 2 better adapt to the underactuated bionic robotic fish platform, zero preload requires that the system can achieve and maintain reliable adsorption purely through the generated negative pressure without relying on mechanical force. This feature improves the overall efficiency and reliability of the system while reducing the complexity of the mechanical structure. Therefore, the present invention also studies the effect of preload on the adsorption force. Figure 8The adsorption process under different preload forces is demonstrated. When the preload forces are 0 N, 3 N, and 5 N, the negative pressures are 293 mbar, 280 mbar, and 284 mbar, respectively. Although applying a larger preload force can generate a relatively strong negative pressure more quickly by introducing mechanical force, the miniaturization and flexible design of the suction cup 221 in the present invention ensures that good adsorption performance can be exhibited even under zero preload conditions. The snapshot sequence of the adsorption component 2 under zero preload force and cyclic adsorption according to the present invention shows that the adsorption component 2 can achieve successful adsorption under zero preload force and remain consistent throughout the cyclic adsorption process.

[0060] like Figure 1 , Figure 2 , Figure 5 and Figure 6 As shown, the bionic robotic fish body 1 includes a cabin section 11, a fish tail 12 and a tail fin 13, and the cabin section 11, the fish tail 12 and the tail fin 13 are connected in sequence; the adsorption-type bionic robotic fish also includes a pectoral fin assembly 3, the pectoral fin assembly 3 includes a first drive assembly, a first pectoral fin 31 and a second pectoral fin 32, the first drive assembly is arranged in the cabin section 11, the first pectoral fin 31 and the second pectoral fin 32 are relatively arranged on the left and right sides of the cabin section 11, and the first drive assembly is respectively connected to the first pectoral fin 31 and the second pectoral fin 32; wherein the first drive assembly is used to adjust the inclination angle of the first pectoral fin 31 and the second pectoral fin 32 relative to the horizontal plane, and to drive the first pectoral fin 31 and the second pectoral fin 32 to swing up and down relative to the cabin section 11.

[0061] It is understandable that, along the moving direction of the bionic robotic fish, the rear end of the cabin section 11 is connected to the front end of the fish tail 12, and the rear end of the fish tail 12 is connected to the root of the tail fin 13. The fish tail 12 of this embodiment is built with a driving structure, and under the action of the driving structure, along the moving direction of the bionic robotic fish, the fish tail 12 can not only drive the tail fin 13 to swing toward the left side of the cabin section 11, but also drive the tail fin 13 to swing toward the right side of the cabin section 11.

[0062] Among them, the tail fin 13 has a shape similar to that of a biological fish, and the tail fin 13 can be made of a flexible material, which makes the tail fin 13 a passive flexible structure, which can not only swing under the drive of the fish tail 12, but also adaptably change its own shape.

[0063] Furthermore, the first drive assembly of the present embodiment can be understood as comprising a decoupled rotation drive part and a swing drive part, the rotation drive part being used to adjust the inclination angle of the first pectoral fin 31 and the second pectoral fin 32 relative to the horizontal plane, and the swing drive part being used to drive the first pectoral fin 31 and the second pectoral fin 32 to swing up and down relative to the cabin section 11.

[0064] Thus, based on the driving action of the first driving component on the first pectoral fin 31 and the second pectoral fin 32 , this embodiment can simulate the movement form of the pectoral fins of biological fish as realistically as possible by controlling the movement state of the first pectoral fin 31 and the second pectoral fin 32 .

[0065] Specifically, the bionic robotic fish of the present invention, by drawing on the biological morphology of fish, sets an adsorption component 2, a pectoral fin component 3 and a fish tail 12 based on the cabin section 11. Not only can the fish tail 12 drive the caudal fin 13 to swing left and right relative to the cabin section 11 to provide a driving force for the forward movement of the bionic robotic fish, but also can realize the adsorption and desorption process between the bionic robotic fish and the target object based on the suction cup 221 of the adsorption component 2, so that the bionic robotic fish can use the adsorption function to reduce the motion loss during navigation, and can also provide a pitch moment for the snorkeling of the bionic robotic fish by changing the frontal area of ​​the first pectoral fin 31 and the second pectoral fin 32 of the pectoral fin component 3 relative to the water surface, and can provide an instantaneous driving force for the movement of the bionic robotic fish by means of the up and down flapping of the first pectoral fin 31 and the second pectoral fin 32, thereby providing the possibility for the bionic robotic fish's motion modes such as emergency stop and acceleration.

[0066] From the above, it can be seen that the bionic robot fish of the present invention can truly imitate the movement modes and biological characteristics of biological fish, has rich movement modes and good movement performance, can achieve high movement flexibility, can realize underwater adsorption tasks, and provides new ideas for complex underwater exploration tasks.

[0067] In some embodiments, in order to facilitate the control of the motion state of the first pectoral fin 31 and the second pectoral fin 32, the drive assembly of this embodiment includes a first steering gear, a second steering gear, a third steering gear, a first mounting seat, and a second mounting seat. The first steering gear is connected to the first mounting seat and the second mounting seat respectively to drive the first mounting seat and the second mounting seat to rotate synchronously along the first axis; the second steering gear and the third steering gear are coaxially arranged along the first axis; the first mounting seat is rotatably arranged at the output end of the second steering gear, and the second mounting seat is rotatably arranged at the output end of the third steering gear.

[0068] The first mounting seat and the first pectoral fin 31 are rotationally connected along the second axis, and a first deflector pin is provided at the output end of the second steering gear, and the first deflector pin is movably inserted into the first guide opening on the first pectoral fin 31; when the second steering gear rotates, the first deflector pin can drive the first pectoral fin 31 to swing back and forth relative to the first mounting seat. The second mounting seat and the second pectoral fin 32 are rotationally connected along the third axis, and a second deflector pin is provided at the output end of the third steering gear, and the second deflector pin is movably inserted into the second guide opening on the second pectoral fin 32; when the third steering gear rotates, the second deflector pin can drive the second pectoral fin 32 to swing back and forth relative to the second mounting seat.

[0069] The first axis of the embodiment is perpendicular to the second axis and the third axis respectively, and the second axis and the third axis are arranged in parallel. At the same time, the first deflector pin of the embodiment is arranged at an angle relative to the central axis of the second steering gear, and the second deflector pin is arranged at an angle relative to the central axis of the third steering gear.

[0070] In actual applications, since the first pectoral fin 31 is rotatably provided on the first mounting seat and the second pectoral fin 32 is rotatably provided on the second mounting seat, the present embodiment can drive the first mounting seat and the second mounting seat to rotate synchronously along the first axis by the first servo, so as to realize synchronous adjustment of the inclination angle of the first pectoral fin 31 and the second pectoral fin 32 relative to the horizontal plane, thereby synchronously adjusting the postures of the first pectoral fin 31 and the second pectoral fin 32, so as to change the frontal area of ​​the first pectoral fin 31 and the second pectoral fin 32 relative to the water surface.

[0071] In some examples, when the bionic robotic fish performs conventional swimming, the present embodiment can set the first pectoral fin 31 and the second pectoral fin 32 to be in a middle position, that is, the surface of the first pectoral fin 31 and the surface of the second pectoral fin 32 are both parallel to the bottom wall of the cabin section 11. This setting can reduce the water-facing area of ​​the first pectoral fin 31 and the second pectoral fin 32, thereby enabling the bionic robotic fish to obtain a higher swimming speed.

[0072] When the bionic robotic fish swims at a low speed, this embodiment can control the surface of the first pectoral fin 31 and the surface of the second pectoral fin 32 to deflect at a preset angle relative to the bottom wall of the cabin section 11. For example, the preset angle can be ± 60°. This setting can increase the lateral resistance of the bionic robotic fish when swimming, making the movement of the bionic robotic fish more stable.

[0073] At the same time, the second servo of the present embodiment can drive the first push pin to rotate around its rotation axis, and based on the movement of the first push pin relative to the first guide port, it can drive the first pectoral fin 31 to swing back and forth relative to the first mounting seat; accordingly, the third servo of the present embodiment can drive the second push pin to rotate around its rotation axis, and based on the movement of the second push pin relative to the second guide port, it can drive the second pectoral fin 32 to swing back and forth relative to the second mounting seat.

[0074] The first guide opening is disposed at the root of the first pectoral fin 31 and is extended along the chord direction of the first pectoral fin 31 ; the second guide opening is disposed at the root of the second pectoral fin 32 and is extended along the chord direction of the second pectoral fin 32 .

[0075] As can be seen from the above, the above-mentioned arrangement of the present invention can change the frontal area of ​​the first pectoral fin 31 and the second pectoral fin 32 relative to the water surface, provide a pitch moment for the snorkeling of the bionic robot fish, and can greatly increase the maneuverability of the bionic robot fish in the startup phase by means of the up and down flapping of the first pectoral fin 31 and the second pectoral fin 32. Based on the instantaneous driving force provided by the flapping mode of the pectoral fin assembly 3, not only can the instantaneous propulsion speed of the bionic robot fish be increased and its turning radius be reduced, but also the movement modes of the bionic robot fish such as emergency stop and reverse swimming can be realized, so that the bionic robot fish has a highly maneuverable three-dimensional movement ability. Obviously, whether it is a flapping mode or a deflection mode, the pectoral fin assembly 3 of this embodiment gives the bionic robot fish a new movement mode.

[0076] In some embodiments, in order to facilitate the first servo to drive the first mounting seat and the second mounting seat to rotate synchronously along the first axis, the drive assembly of this embodiment is further provided with a gear assembly and a connecting rod.

[0077] Specifically, the gear assembly of this embodiment includes a first gear structure and a second gear structure; the output end of the first servo is connected to the first gear structure, the first gear structure and the second gear structure are meshed, and the second gear structure is coaxially connected to the first mounting seat.

[0078] At the same time, the extending direction of the connecting rod is parallel to the first axis, so that the connecting rod is eccentrically arranged relative to the first axis; one end of the connecting rod is connected to the second gear structure, and the other end is connected to the second mounting seat.

[0079] In this way, the first servo of the present embodiment can drive the first gear structure to rotate around its central axis, so that the first gear structure drives the second gear structure to rotate. Under the transmission of the second gear structure, the connecting rod can drive the first mounting seat and the second mounting seat to rotate synchronously along the first axis, thereby realizing synchronous adjustment of the inclination angle of the first pectoral fin 31 and the second pectoral fin 32 relative to the horizontal plane.

[0080] like Figure 1 , Figure 2 and Figure 6 As shown, the adsorption-type bionic robot fish also includes a tail 12 drive assembly, which includes multiple drive joints. The multiple drive joints are connected in series along the extension direction of the tail 12. One of the multiple drive joints close to the cabin section 11 is connected to the cabin section 11, and one of the multiple drive joints far from the cabin section 11 is connected to the tail fin 13.

[0081] Specifically, the driving joints of this embodiment can adopt simulated servos, and two adjacent simulated servos are connected by an adapter frame. In practical applications, this embodiment can realize active bending deformation of the fishtail 12 in shape by controlling the rotation angle of each driving joint along the extension direction of the fishtail 12. The fishtail 12 can drive the tail fin 13 to swing toward the left side of the cabin section 11, and can also drive the tail fin 13 to swing toward the right side of the cabin section 11, so as to have higher maneuverability. Among them, the fishtail 12 of this embodiment can be specifically provided with three driving joints, and the three driving joints are connected in series along the extension direction of the bionic fishtail 12. In an optional embodiment, the adsorption-type bionic robotic fish further includes a sensor component, and the sensor component, the pectoral fin component 3, and the tail 12 driving component are all electrically connected to the control mainboard. The sensor component includes at least one of a visual module 5, a depth sensor, and an inertial measurement unit.

[0082] Among them, the control main board includes a first circuit board and a second circuit board. The first circuit board can be equipped with a chip of model STM32F407. The depth sensor and the inertial measurement unit are respectively connected to the first circuit board. The first circuit board can control the working status of the driving component corresponding to the pectoral fin component 3 and the driving joint corresponding to the tail 12 according to the depth information collected by the depth sensor and the navigation information provided by the inertial measurement unit.

[0083] At the same time, the second circuit board of this embodiment can be equipped with a Raspberry Pi 4B processor, the visual module 5 is connected to the second circuit board, and the second circuit board and the first circuit board are connected via serial port communication.

[0084] The visual module 5 of this embodiment can be arranged at the top or front end of the cabin section 11. The visual module 5 can adopt an industrial camera known in the art. The second circuit board can process and identify features of the image information collected by the visual module 5. The first circuit board can control the working status of the driving component corresponding to the above-mentioned pectoral fin component 3 and the driving joint corresponding to the tail 12 according to the information processed and obtained by the second circuit board.

[0085] Based on the above configuration, the bionic robotic fish of this embodiment can have better perception ability and superior maneuverability underwater.

[0086] In an optional embodiment, the adsorption-type bionic robotic fish also includes a battery assembly, which is disposed in the bionic robotic fish body 1. The bionic robotic fish body 1 is provided with a charging port, at least part of which is exposed on the surface of the bionic robotic fish body 1, and the charging port and the battery assembly are electrically connected.

[0087] Specifically, the battery assembly of this embodiment includes multiple lithium batteries. The battery assembly can provide working power for various devices built into the bionic robotic fish, and provide support for the bionic robotic fish to independently complete underwater operation tasks.

[0088] At the same time, the present embodiment can also charge the battery assembly regularly through the charging port to ensure that the bionic robotic fish can be reused after the power is exhausted.

[0089] Among them, the charging port of this embodiment can be set at the front end of the cabin section 11. When setting the charging port, it is necessary to ensure the waterproof sealing between the charging port and the cabin section 11.

[0090] As can be seen from the above, after obtaining the optimal suction cup 221 structural parameters, the present invention has developed a high-performance suction cup 221 array. Specifically, the manufacturing angle of 30° and the Shore hardness of 35 A fully take into account the strength and adaptability of the suction cup 221. In addition, an intelligent adsorption system is constructed through fuzzy control and finite state machine methods. In this process, the present invention designs and executes various intelligent adsorption tasks, and quantitatively analyzes the output of the adsorption system to verify its reliability.

[0091] On the one hand, by defining fuzzy sets and membership functions, a fuzzy control method is used to process the distance and pressure data collected by the sensor. First, normalization is performed according to the range of the input and output variables; then, the input is fuzzified using a triangular membership function; for the fuzzy control output, the maximum member principle is used for defuzzification. On the other hand, a finite state machine logic is used to control the adsorption scheduling process. First, the system enters the initial state and prepares to collect sensor data; then, the adsorption state is evaluated using a fuzzy method; then, the negative pressure pump 21 is controlled according to the adsorption state to achieve adsorption; finally, the state machine continuously cycles to dynamically adjust and control the adsorption process through state transitions. The method proposed in the present invention helps to ensure that the robot fish dynamically adjusts the output of its adsorption component 2 according to different target surfaces, thereby achieving intelligent adsorption.

[0092] The bionic robot fish developed by the present invention can autonomously perform intelligent adsorption tasks by integrating the proposed adsorption mechanism and fuzzy control based on finite state machines, and demonstrates adaptability to various scenarios. The experimental process is as follows: (1) The robot fish approaches the target and collects information using sensors; (2) The microcontroller uses the fuzzy control method based on finite state machines to process the input information and generate control outputs for the solenoid valve. The present invention experimentally explores the adsorption process of planar targets, curved targets and two-stage targets. Specifically, for planar targets, two distance sensors 23 are activated and the entire negative pressure pump 21 is turned on. For curved targets, the front distance sensor 23 is activated to open the corresponding solenoid valve channel. For two-stage targets, in the first stage, the curved target activates the rear distance sensor 23 and opens the rear solenoid valve channel. In the second stage, when the planar target gradually approaches the threshold of the distance sensor 23, the remaining solenoid valve channels are dynamically opened.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An adsorption-type bionic robotic fish, characterized in that: include: An adsorption component and a bionic robotic fish body, wherein the adsorption component is installed on the bionic robotic fish body; The adsorption assembly includes a negative pressure pump, a control mainboard and multiple adsorption modules, and the multiple adsorption modules are all connected to the negative pressure pump; wherein each of the adsorption modules includes a suction cup, an adsorption channel, a desorption channel, a first solenoid valve and a second solenoid valve, the suction cup is fluidically connected to the negative pressure pump through the adsorption channel, the desorption channel is fluidically connected to the adsorption channel, the first solenoid valve is installed in the adsorption channel, the second solenoid valve is installed in the desorption channel, and the negative pressure pump, the first solenoid valve and the second solenoid valve are all electrically connected to the control mainboard.

2. The adsorption-type bionic robotic fish according to claim 1, characterized in that: The Shore hardness of the suction cup is 25A-35A; and / or, The inclination angle of the suction cup is 15°~45°.

3. The adsorption-type bionic robotic fish according to claim 1, characterized in that: The adsorption component also includes a distance sensor, which is installed on the bionic robotic fish body and located between two adjacent suction cups; wherein the negative pressure pump, the distance sensor, the first solenoid valve and the second solenoid valve are all electrically connected to the control main board, and the control main board is configured to control the opening of the negative pressure pump and the corresponding first solenoid valve according to the distance value of the distance sensor.

4. The adsorption-type bionic robotic fish according to claim 3, characterized in that: Each of the adsorption modules also includes a pressure sensor, which is installed in the adsorption channel and is used to obtain the pressure value in the adsorption channel. The pressure sensor is electrically connected to the control main board. The control main board is also configured to control the action of the negative pressure pump and the corresponding first solenoid valve according to the pressure value of the pressure sensor, so that the pressure value is equal to the target pressure value.

5. The adsorption-type bionic robotic fish according to claim 1, characterized in that: The plurality of suction cups corresponding to the plurality of adsorption modules are sequentially arranged at intervals along the length direction of the bionic robotic fish body.

6. The adsorption-type bionic robotic fish according to any one of claims 1 to 5, characterized in that: The bionic robotic fish body comprises a cabin section, a fish tail and a tail fin, wherein the cabin section, the fish tail and the tail fin are connected in sequence; The adsorption-type bionic robotic fish also includes a pectoral fin assembly, which includes a first drive assembly, a first pectoral fin and a second pectoral fin, wherein the first drive assembly is disposed in the cabin section, the first pectoral fin and the second pectoral fin are relatively disposed on the left and right sides of the cabin section, and the first drive assembly is respectively connected to the first pectoral fin and the second pectoral fin; wherein the first drive assembly is used to adjust the inclination angle of the first pectoral fin and the second pectoral fin relative to the horizontal plane, and to drive the first pectoral fin and the second pectoral fin to swing up and down relative to the cabin section.

7. The adsorption-type bionic robotic fish according to claim 6, characterized in that: The adsorption-type bionic robotic fish also includes a fishtail drive assembly, which includes multiple drive joints. The multiple drive joints are connected in series along the extension direction of the fishtail, one of the multiple drive joints close to the cabin section is connected to the cabin section, and one of the multiple drive joints far from the cabin section is connected to the tail fin.

8. The adsorption-type bionic robotic fish according to claim 7, characterized in that: The adsorption-type bionic robotic fish also includes a sensor component, and the sensor component, the pectoral fin component and the tail drive component are all electrically connected to the control mainboard.

9. The adsorption-type bionic robotic fish according to claim 8, characterized in that: The sensing component includes at least one of a vision module, a depth sensor and an inertial measurement unit.

10. The adsorption-type bionic robotic fish according to any one of claims 1 to 5, characterized in that: The adsorption-type bionic robotic fish also includes a battery assembly, which is disposed in the bionic robotic fish body. The bionic robotic fish body is provided with a charging port, at least part of which is exposed on the surface of the bionic robotic fish body, and the charging port is electrically connected to the battery assembly.

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