Biomimetic flexible fish tail with neutral buoyancy and manufacturing method

Abstract

The application provides a bionic flexible fish tail with neutral buoyancy and a manufacturing method. The bionic flexible fish tail comprises a main skeleton plate, a support skeleton, a fixing member and a flexible fish tail outer skin. The main skeleton plate is designed according to the shape of a biological fish tail and comprises a main body part and a tail fin. The main skeleton plate is made of elastic metal material. The support skeleton is designed according to the shape of the biological fish tail and is divided into two groups. The two groups of support skeletons are symmetrically arranged on two surfaces of the main body part of the main skeleton plate and form a fish tail overall skeleton together with the main skeleton plate. The fixing member is connected to one end of the main skeleton plate away from the tail fin. The flexible fish tail outer skin is arranged on the outer surfaces of the fixing member and the fish tail overall skeleton and forms a closed hollow air cabin together with the fish tail overall skeleton. The arrangement of the hollow air cabin enables the total weight of the bionic flexible fish tail to be equal to the displacement weight of the bionic flexible fish tail. The bionic flexible fish tail is a bionic flexible fish tail which realizes compliance optimization as a whole.

Description

Technical Field

[0001] This invention relates to the field of biomimetic technology, and in particular to a biomimetic flexible fish tail with neutral buoyancy and its manufacturing method. Background Technology

[0002] In recent years, underwater biomimetic robots have attracted widespread attention due to their high efficiency, high maneuverability, and environmental friendliness, demonstrating significant research value in underwater operations such as marine resource exploration and autonomous search and rescue. Classic biomimetic swimming modes include the body / tail fin mode (BCF) and the intermediate fin / paired fin mode (MPF). The BCF mode, in particular, derives its main propulsion from the compliant tail movement, making it suitable for efficient cruising and autonomous search tasks, and thus a research hotspot. To further improve the swimming speed and propulsion efficiency of BCF-type underwater robots, researchers have conducted extensive research on compliant fish tails in recent years. By designing passive joints and flexible mechanisms, various biomimetic fish tails with passive compliance have been developed, significantly optimizing the swimming speed and energy consumption of underwater robots and narrowing the propulsion performance gap with biological fish.

[0003] Although there is considerable research on the compliance of biomimetic fish tails, most existing studies focus on specific platforms, lacking systematic and comprehensive solutions and limiting their transferability. Kancharala et al. designed a passive joint at the tail peduncle, using torsion springs as joint connections to achieve different levels of compliance, and verified the performance optimization results through theory and experiments. Chen et al. combined passive joints and flexible tail fins, designing an underwater biomimetic robot with high explosive leaping ability based on torsion springs and carbon fiber plates. However, the elasticity of the torsion springs in the passive joints is limited by the size of the mechanism, making it difficult to achieve optimal compliance. Lu et al. connected two rigid chambers at the tail with spring plates and added two flexible connectors to simulate a biological fish tail, achieving improvements in fish-like posture and swimming speed. Zhong et al. embedded a tension spring mechanism in the tail of a fish-like robot, with the tail fin and actuator connected to the two sides of the tension spring respectively. The pretension force applied to the torsion spring by the actuator achieved controllable changes in the compliance of the tail fin, realizing a propulsion efficiency gain for the robot over a wide speed range. White et al. added multiple free joints to the tail and conducted extensive experimental tests at different frequencies. The results showed that flexible design can effectively improve swimming speed and reduce energy consumption costs.

[0004] However, the aforementioned biomimetic fish tail designs only achieve localized compliance optimization by incorporating flexible components, making it difficult to simulate the overall smooth flapping effect of a biological fish tail. Furthermore, localized compliance mechanisms are often limited by the size of the elastic connectors, significantly hindering the improvement of the performance of flexible fish tails. Summary of the Invention

[0005] This invention provides a biomimetic flexible fish tail with neutral buoyancy and a manufacturing method thereof, in order to solve the defect of existing biomimetic fish tails that only achieve localized compliance optimization and are difficult to simulate the overall smooth flapping effect of a biological fish tail, and to realize a biomimetic flexible fish tail that achieves overall compliance optimization.

[0006] This invention provides a biomimetic flexible fish tail with neutral buoyancy, comprising: a main skeleton plate, a supporting skeleton, a fixing element, and a flexible fish tail outer skin;

[0007] The main skeleton plate is designed according to the shape of a fish tail and includes a main body and a tail fin. The main skeleton plate is made of elastic metal material.

[0008] The supporting skeleton is designed according to the shape of the fish tail and the multiple supporting skeletons are divided into two groups. The two groups of supporting skeletons are symmetrically arranged on two sides of the main body of the main skeleton plate, forming the overall fish tail skeleton with the main skeleton plate.

[0009] The fastener is connected to the end of the main frame plate away from the tail fin;

[0010] The flexible fishtail outer skin is disposed on the outer surface of the fixing member and the overall fishtail skeleton, and forms a sealed air chamber with the overall fishtail skeleton. The arrangement of the air chamber ensures that the total weight of the bionic flexible fishtail is equal to the weight of the bionic flexible fishtail after drainage, thereby giving the bionic flexible fishtail the characteristic of neutral buoyancy.

[0011] According to the present invention, a biomimetic flexible fish tail with neutral buoyancy is provided, wherein each of the supporting skeletons is vertically arranged on two surfaces of the main body of the main skeleton plate, and each of the supporting skeletons is respectively arranged perpendicular to the axis of the main skeleton plate.

[0012] According to the present invention, a biomimetic flexible fish tail with neutral buoyancy is provided, wherein the supporting frame includes an arc-shaped structure and a supporting structure, and the supporting structure is disposed on the inner arc surface of the arc-shaped structure.

[0013] According to the present invention, a biomimetic flexible fish tail with neutral buoyancy is provided, which further includes a waterproof membrane disposed on the outer surface of the fixing member and the overall fish tail skeleton, located between the overall fish tail skeleton and the flexible fish tail skin.

[0014] The present invention also provides an underwater biomimetic robotic fish, comprising a biomimetic flexible fish tail with neutral buoyancy and a biomimetic robotic fish body as described above;

[0015] The bionic robotic fish body is connected to the bionic flexible fish tail via a connector, wherein the connector is rotatably connected to the bionic robotic fish body, and the axis of rotation of the connector is perpendicular to the cross section of the bionic robotic fish body, and the connector is fixedly connected to the bionic flexible fish tail.

[0016] This invention also provides a method for manufacturing a biomimetic flexible fishtail with neutral buoyancy, comprising:

[0017] Based on a 3D model of a biological fish tail, a biomimetic flexible fish tail main skeleton plate, supporting skeleton and fixing components are made. The main skeleton plate includes a main body and a tail fin. The tail fin is a sickle-shaped structure set at one end of the main body.

[0018] The multiple supporting frames are divided into two groups, and the two groups of supporting frames are symmetrically installed on two sides of the main body of the main frame plate to form a fish tail overall frame with the main frame plate.

[0019] The fish tail skeleton is installed on the fixing member, and at least one layer of waterproof film is wrapped around the outer peripheral surface of the non-tail fin part of the fish tail skeleton to obtain the casting foundation.

[0020] A fish tail mold was designed based on the 3D model of the described fish tail.

[0021] The fish tail mold is assembled onto the casting base, and silicone is poured between the fish tail mold and the casting base to form a flexible silicone fish tail skin on the outer circumference of the casting base. After the silicone solidifies, the fish tail mold is removed to obtain a biomimetic flexible fish tail.

[0022] The weight of the resulting biomimetic flexible fish tail is equal to the total weight of the biomimetic flexible fish tail, which is equal to the weight of the biomimetic flexible fish tail after drainage.

[0023] According to the present invention, a method for manufacturing a biomimetic flexible fish tail with neutral buoyancy is provided. The method involves fabricating a main skeleton plate, a supporting skeleton, and fixing components based on a 3D model of a biological fish tail. The main skeleton plate includes a main body and a tail fin. The tail fin is a sickle-shaped structure disposed at one end of the main body.

[0024] A 3D model of the fish tail of the organism is established, and the shapes of the main skeleton plate, the supporting skeleton and the fixing components are designed based on the 3D model;

[0025] The dimensions of the main skeleton plate, the supporting skeleton, and the fixing member are determined based on the material density of the main skeleton plate, the supporting skeleton, the fixing member, and the flexible fish tail outer skin, as well as the design drainage weight of the bionic flexible fish tail.

[0026] Based on the shape and size of the main frame plate, the supporting frame, and the fixing member, the main frame plate, the supporting frame, and the fixing member are manufactured.

[0027] According to the present invention, a method for manufacturing a biomimetic flexible fish tail with neutral buoyancy is provided, wherein the design of the fish tail mold based on the 3D model of the biological fish tail includes:

[0028] Based on the 3D model of the fish tail, a first mold, a second mold, and a third mold are designed respectively. The first mold is the mold for the fixing part, the second mold is the mold for the tail fin part, and the third mold is the mold for the main body part.

[0029] According to the present invention, a method for manufacturing a biomimetic flexible fishtail with neutral buoyancy is provided, comprising: assembling the fishtail mold onto the casting base; casting silicone between the fishtail mold and the casting base to form a silicone flexible fishtail outer skin on the outer circumferential surface of the casting base; and removing the fishtail mold after the silicone has solidified to obtain the biomimetic flexible fishtail. The method includes:

[0030] The first mold is assembled around the outer periphery of the fixing member of the foundation. After successful assembly, silicone is poured between the first mold and the fixing member until the silicone submerges the nearest opening of the waterproof membrane.

[0031] After the silicone in the first mold solidifies, the second mold is assembled around the outer periphery of the tail fin on the foundation. After successful assembly, silicone is poured between the tail fins in the second mold until the silicone submerges the nearest opening of the waterproof membrane.

[0032] After the silicone in the second mold solidifies, the third mold is assembled around the outer periphery of the tail of the casting foundation. After successful assembly, silicone is poured between the tail fins in the third mold.

[0033] After the silicone in the third mold solidifies, the first mold, the second mold, and the third mold are removed together to obtain the biomimetic flexible fish tail.

[0034] According to the present invention, a method for manufacturing a biomimetic flexible fish tail with neutral buoyancy is provided, wherein two sets of the supporting skeleton are symmetrically installed on two surfaces of the main body of the main skeleton plate by means of hot melt adhesive, so that the hot melt adhesive can be detached during the use of the biomimetic flexible fish tail.

[0035] The present invention provides a biomimetic flexible fish tail with neutral buoyancy and a manufacturing method thereof. On the one hand, the main skeleton plate of the biomimetic flexible fish tail is made of elastic metal material and is provided with an integrated flexible fish tail skin, which realizes the overall smooth optimization of the biomimetic fish tail, and has a smooth propulsion posture, high propulsion performance and low energy consumption. On the other hand, the weight of the biomimetic flexible fish tail is the same as the displacement weight of the biomimetic flexible fish tail, which ensures the balance of gravity and buoyancy, has the characteristics of neutral buoyancy, and ensures the stability of dynamic propulsion performance. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a perspective structural schematic diagram of the biomimetic flexible fish tail with neutral buoyancy provided by the present invention.

[0038] Figure 2 This is a partial cross-sectional structural diagram of the biomimetic flexible fish tail with neutral buoyancy provided by the present invention.

[0039] Figure 3 This is a schematic diagram of the exploded structure of the biomimetic flexible fish tail with neutral buoyancy provided by the present invention.

[0040] Figure 4 This is a schematic diagram of the underwater biomimetic robotic fish provided by the present invention;

[0041] Figure 5 This is a schematic diagram of the process for manufacturing a biomimetic flexible fish tail with neutral buoyancy provided by the present invention.

[0042] Figure 6 This is a flowchart illustrating the method for manufacturing the main frame plate, supporting frame, and fasteners provided by the present invention.

[0043] Figure 7 This is one of the structural schematic diagrams of the fish tail mold provided by the present invention;

[0044] Figure 8 This is the second structural schematic diagram of the fish tail mold provided by the present invention;

[0045] Figure 9 This is one of the flowcharts illustrating the method for manufacturing the flexible fishtail outer skin provided by the present invention;

[0046] Figure 10 This is the second flowchart illustrating the method for manufacturing the flexible fishtail outer skin provided by this invention.

[0047] Figure label:

[0048] 101. Main skeleton plate; 102. Supporting skeleton; 103. Fixing components; 104. Flexible fish tail skin; 105. Medium air chamber; 106. Bionic robotic fish body; 107. First mold; 108. Second mold; 109. Third mold; 110. Waterproof membrane. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0050] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., 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 embodiments of the present 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 the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0051] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0052] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0054] The following is combined with Figures 1-3 The present invention describes a biomimetic flexible fish tail with neutral buoyancy.

[0055] like Figure 1 , 2 As shown in Figure 3, the biomimetic flexible fish tail includes: a main skeleton plate 101, a supporting skeleton 102, a fixing member 103, and a flexible fish tail outer skin 104; the main skeleton plate 101 is designed according to the shape of a biological fish tail, including a main body and a tail fin, and the main skeleton plate 101 is made of an elastic metal material; the supporting skeleton 102 is designed according to the shape of a biological fish tail, and multiple supporting skeletons 102 are divided into two groups, with the two groups of supporting skeletons 102 symmetrically arranged on two surfaces of the main body of the main skeleton plate 101, and... The main skeleton plate 101 forms the overall fish tail skeleton; the fixing member 103 is connected to the end of the main skeleton plate 101 away from the tail fin; the flexible fish tail skin 104 is disposed on the outer surface of the fixing member 103 and the overall fish tail skeleton, and forms a sealed air chamber 105 with the overall fish tail skeleton. The arrangement of the air chamber 105 makes the total weight of the bionic flexible fish tail equal to the weight of the bionic flexible fish tail after drainage, thereby giving the bionic flexible fish tail the characteristic of neutral buoyancy.

[0056] Specifically, the main skeleton plate 101 is designed according to the shape of a fish tail and is made of elastic metal material with a thickness between 0.3mm and 1.0mm. It imitates the vertebrae and the skeleton composed of fish bones in a fish tail. For example, the elastic metal material can be a quenched elastic steel plate. The support skeleton 102 is also designed according to the shape of a fish tail. Multiple support skeletons 102 are divided into two groups and are respectively set on two sides of the main skeleton plate 101. They are symmetrically arranged. After the support skeleton 102 is installed, it will not affect the swing of the main skeleton plate 101. The support skeleton 102 and the main skeleton plate 101 form the overall skeleton of the fish tail.

[0057] The fastener 103 is used to connect the biomimetic flexible fish tail to the main body of the biomimetic robotic fish. The fastener 103 is connected to the end of the main skeleton plate 101 away from the tail fin. For example, the fastener 103 can be provided with a slot, and the main skeleton plate 101 away from the tail fin can be provided with an installation plug. The fastener 103 is connected to the main skeleton plate 101 by inserting the installation plug into the installation slot. The fastener 103 can be made of nylon. The flexible fish tail skin 104 covers the fastener 103 and the overall fish tail skeleton, forming a sealed air chamber 105 between it and the overall fish tail skeleton. The flexible fish tail skin 104 can be made of silicone material, specifically 0-degree human-grade silicone material molded in one piece. During the swimming process of the simulated fish body, based on the elastic main skeleton plate 101 and the flexible fish tail skin 104, the biomimetic flexible fish tail can exhibit a smooth propulsion posture.

[0058] Furthermore, the configuration of the air chamber 105 ensures that the total weight of the biomimetic flexible fish tail equals its weight after displacement, thus making its buoyancy equal to its gravity. When the biomimetic flexible fish tail moves in water after being connected to the simulated robotic fish body, it does not require additional buoyancy or gravity, ensuring the stability of the robotic fish's posture and dynamic propulsion performance.

[0059] The biomimetic flexible fish tail provided by this invention has two aspects. First, the main skeleton plate 101 of the biomimetic flexible fish tail is made of elastic metal material and is provided with an integrated flexible fish tail skin 104, which realizes the overall smooth optimization of the biomimetic fish tail, and has a smooth propulsion posture, high propulsion performance and low energy consumption. Second, the weight of the biomimetic flexible fish tail is the same as the weight of the water displacement of the biomimetic flexible fish tail, which ensures the balance of gravity and buoyancy, has the characteristics of neutral buoyancy, and ensures the stability of dynamic propulsion performance.

[0060] In one embodiment, each of the support frames 102 is vertically disposed on two surfaces of the main body of the main frame plate 101, and each of the support frames 102 is respectively disposed perpendicular to the axis of the main frame plate 101.

[0061] Specifically, such as Figure 3 As shown, each support frame 102 is vertically disposed on two surfaces of the main body of the main frame plate 101 and perpendicular to the axis of the main frame plate 101, which is the line on the main frame plate 101 corresponding to the position of the fish's vertebrae. The support frame 102 can be fixedly disposed on the main frame plate 101, or it can be covered and disposed on the main frame plate 101 by a flexible fish tail skin 104. Both the support frame 102 and the fastener 103 can be made of nylon material.

[0062] In one embodiment, the support frame 102 includes an arc-shaped structure and a support structure, wherein the support structure is disposed on the inner arc surface of the arc-shaped structure.

[0063] Specifically, the support frame 102 includes an arc-shaped structure and a support structure. The support structure is disposed on the inner arc surface of the arc-shaped structure to reduce the deformation of the support frame 102 when the biomimetic flexible fish tail receives lateral pressure.

[0064] In one embodiment, a waterproof membrane 110 is also included, which is disposed on the outer surface of the fastener 103 and the overall fish tail skeleton, located between the overall fish tail skeleton and the flexible fish tail skin 104.

[0065] Specifically, the biomimetic flexible fish tail may also include a waterproof membrane 110 disposed on the outer surface of the fixing member 103 and the overall fish tail skeleton, located between the overall fish tail skeleton and the flexible fish tail skin 104. On the one hand, it improves waterproofness and further ensures the airtightness of the air chamber. On the other hand, it assists in supporting the silicone casting of the flexible fish tail skin 104 during the manufacturing process of the biomimetic flexible fish tail.

[0066] The present invention also provides an underwater biomimetic robotic fish, comprising a biomimetic flexible fish tail with neutral buoyancy as described above and a biomimetic robotic fish body 106; the biomimetic robotic fish body 106 is connected to the biomimetic flexible fish tail via a connector, wherein the connector is rotatably connected to the biomimetic robotic fish body, and the axis of rotation of the connector is perpendicular to the cross section of the biomimetic robotic fish body, and the connector is fixedly connected to the biomimetic flexible fish tail.

[0067] For details, please refer to Figure 4 As shown, the underwater simulated robotic fish consists of a bionic robotic fish body and a bionic flexible fish tail, connected by a connector. For example, this connector may include two pieces: one located near the dorsal side of the bionic robotic fish body 106, and the other near the belly side. One end of the connector is rotatably connected to the bionic robotic fish body 106, with the axis of rotation perpendicular to the cross-section of the bionic robotic fish body, which is the cross-section perpendicular to the main skeleton plate 101 of the bionic flexible fish tail, along the direction of the fish body. The other end of the connector is fixedly connected to a fixing member 103, for example, by screws. This connection method allows the bionic flexible fish tail to provide thrust by oscillating, mimicking the movement of a biological fish tail, when the bionic robotic fish body 106 moves.

[0068] The underwater simulated robotic fish provided by this invention has two advantages. First, the underwater simulated robot has an overall smooth bionic flexible fish tail, which has a smooth propulsion posture, high propulsion performance and low energy consumption. Second, the weight of the bionic flexible fish tail of the underwater simulated robot is the same as the weight of the bionic flexible fish tail when it is displaced, which ensures the balance of gravity and buoyancy, has the characteristics of neutral buoyancy, and ensures the stability of dynamic propulsion performance.

[0069] This invention also provides a method for manufacturing a biomimetic flexible fishtail with neutral buoyancy, which can be used to manufacture the aforementioned biomimetic flexible fishtail, such as... Figure 5 As shown, the method includes:

[0070] S501: Based on a 3D model of a biological fish tail, fabricate a biomimetic flexible fish tail main skeleton plate 101, a supporting skeleton 102, and a fixing component 103. The main skeleton includes a main body and a tail fin, and the tail fin is a sickle-shaped structure set at one end of the main body.

[0071] S502: Divide the plurality of support frames 102 into two groups, and symmetrically install the two groups of support frames 102 on two surfaces of the main body of the main frame plate 101, so as to form a fish tail overall frame with the main frame plate 101.

[0072] S503: Install the fish tail skeleton onto the fixing member 103, and wrap at least one layer of waterproof film around the outer peripheral surface of the non-tail fin part of the fish tail skeleton to obtain the casting foundation.

[0073] S504: Design a fish tail mold based on the 3D model of the fish tail of the organism.

[0074] S505: Assemble the fish tail mold onto the casting foundation, pour silicone between the fish tail mold and the casting foundation to form a flexible silicone fish tail outer skin 104 on the outer circumferential surface of the casting foundation. After the silicone solidifies, remove the fish tail mold to obtain a biomimetic flexible fish tail. The weight of the obtained biomimetic flexible fish tail is equal to the total weight of the biomimetic flexible fish tail and equal to the weight of the biomimetic flexible fish tail after drainage.

[0075] The present invention provides a method for manufacturing a biomimetic flexible fish tail with neutral buoyancy. On the one hand, the main skeleton plate 101 of the biomimetic flexible fish tail is made of elastic metal material and is provided with an integrated flexible fish tail skin 104, which realizes the overall smooth optimization of the biomimetic fish tail, and has a smooth propulsion posture, high propulsion performance and low energy consumption. On the other hand, the weight of the biomimetic flexible fish tail is the same as the displacement weight of the biomimetic flexible fish tail, which ensures the balance of gravity and buoyancy, has the characteristics of neutral buoyancy, and ensures the stability of dynamic propulsion performance.

[0076] In one embodiment, such as Figure 6As shown, the 3D model based on a biological fish tail is used to fabricate a biomimetic flexible fish tail, comprising a main skeleton plate 101, a supporting skeleton 102, and a fixing member 103. The main skeleton plate 101 includes a main body and a tail fin. The tail fin is a sickle-shaped structure located at one end of the main body, including:

[0077] S601: Establish a 3D model of the fish tail of the organism, and design the shape of the main skeleton plate 101, the supporting skeleton 102 and the fixing member 103 according to the 3D model.

[0078] S602: Determine the dimensions of the main skeleton plate 101, the support skeleton 102, and the fixation member 103 based on the material density of the main skeleton plate 101, the support skeleton 102, the fixation member 103, and the flexible fish tail skin 104 to be used, as well as the design drainage weight of the bionic flexible fish tail.

[0079] S603: Based on the shape and size of the main frame plate 101, the support frame 102 and the fastener 103, manufacture the main frame plate 101, the support frame 102 and the fastener 103.

[0080] Specifically, because the 3D model of the biological fish tail should be the same size and shape as the manufactured biomimetic flexible fish tail, the main skeleton plate 101 and the supporting skeleton 102 designed based on the 3D model should be smaller than the outer contour of the 3D model after assembly, so as to leave room for the flexible fish tail skin 104. The thickness of the main skeleton plate 101 is between 0.3mm and 1.0mm, and the flexible fish tail skin is made of 0-degree human-grade silicone material.

[0081] To ensure that the weight of the fabricated biomimetic flexible fish tail is infinitely close to its drainage volume, the design drainage weight M of the biomimetic flexible fish tail was calculated based on the drainage volume of a 3D model of a biological fish tail during fabrication. d Thus, the redirected static buoyancy force F can be calculated. s =M d -M all Ideally, the optimal static buoyancy force satisfies F. s =0.

[0082] Considering engineering aspects, the initial assumption is that the static buoyancy force is slightly greater than 0, i.e. Specifically, after determining the materials of the main frame plate 101, the supporting frame 102, and the fixing member 103, adjustments are made to their dimensions, such as the thickness of the main frame plate and the thickness of the supporting frame, so that, after adding the estimated weight of the flexible fishtail outer skin 104, the final weight is slightly less than the preset value of the bionic flexible fishtail's drainage weight. This ensures that the drainage volume is redundant compared to the initial set weight of the bionic flexible fishtail. Therefore, during the setting of the flexible fishtail outer skin 104, the amount of silicone used can be fine-tuned according to the actual weight of the mechanism, thereby facilitating the achievement of a neutral buoyancy effect.

[0083] In one embodiment, such as Figure 7 and Figure 8 As shown, the design of the fish tail mold based on the 3D model of the fish tail includes:

[0084] Based on the 3D model of the fish tail, a first mold 107, a second mold 108, and a third mold 109 are designed respectively. The first mold 107 is the mold for the fixing part 103, the second mold 108 is the mold for the tail fin part, and the third mold 109 is the mold for the main body part.

[0085] Specifically, when setting up the 3D model of the fish tail, to facilitate the subsequent pouring of silicone, molds can be set up for multiple parts separately so that they can be poured in sections later.

[0086] In one embodiment, such as Figure 9 and Figure 10 As shown, the process involves assembling the fishtail mold onto the casting foundation, pouring silicone between the fishtail mold and the casting foundation to form a flexible silicone fishtail outer skin 104 on the outer circumferential surface of the casting foundation, and removing the fishtail mold after the silicone has solidified to obtain a biomimetic flexible fishtail, comprising:

[0087] S901: Assemble the first mold 107 around the outer periphery of the fixing member 103 of the foundation. After successful assembly, pour silicone between the first mold 107 and the fixing member 103 until the silicone submerges the nearest opening of the waterproof membrane.

[0088] S902: After the silicone in the first mold 107 solidifies, the second mold 108 is assembled on the outer periphery of the tail fin of the casting foundation. After successful assembly, silicone is poured between the tail fins in the second mold 108 until the silicone is submerged at the nearest opening of the waterproof membrane.

[0089] S903: After the silicone in the second mold 108 solidifies, the third mold 109 is assembled on the outer periphery of the tail of the casting foundation. After successful assembly, silicone is poured between the tail fin and the third mold 109.

[0090] S904: After the silicone in the third mold 109 cools and solidifies, the first mold 107, the second mold 108 and the third mold 109 are removed to obtain the biomimetic flexible fish tail.

[0091] Specifically, when pouring silicone into the foundation, the pouring is carried out in stages. First, the outer periphery of the fixing component 103 and the outer periphery of the tail fin are poured to facilitate the sealing of the opening of the waterproof membrane. Specifically, the outer periphery of the fixing component 103 can be poured first and then the outer periphery of the tail fin, or the outer periphery of the tail fin can be poured first and then the outer periphery of the fixing component 103. After the outer periphery of the fixing component 103 and the outer periphery of the tail fin have solidified, the outer periphery of the main body is poured. If necessary, a pouring port also needs to be set on the third mold 109.

[0092] When dismantling the mold, the last section is poured and solidified before being dismantled.

[0093] In one embodiment, the two sets of support frames 102 are symmetrically installed on two surfaces of the main body of the main frame plate 101 using hot melt adhesive, so that the hot melt adhesive can be detached during use of the biomimetic flexible fish tail.

[0094] Specifically, hot melt adhesive is used to symmetrically install two sets of support frames 102 on the two surfaces of the tail of the main frame plate 101. During subsequent use of the bionic flexible fish tail, it will detach with movement. The arc-shaped structure of the support frame 102 is wrapped by the silicone material of the flexible fish tail skin, so that it will shift position with the main frame plate as the flexible fish tail skin swings, making the bionic flexible fish tail more flexible.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A biomimetic flexible fish tail with neutral buoyancy, characterized in that, include: Main frame plate, supporting frame, fasteners, flexible fishtail skin and waterproof membrane; The main skeleton plate is designed according to the shape of a fish tail and includes a main body and a tail fin. The main skeleton plate is made of elastic metal material. The supporting skeleton is designed according to the shape of the fish tail and the multiple supporting skeletons are divided into two groups. The two groups of supporting skeletons are symmetrically arranged on two sides of the main body of the main skeleton plate, forming the overall fish tail skeleton with the main skeleton plate. The supporting frame includes an arc-shaped structure and a supporting structure. The supporting structure is disposed on the inner arc surface of the arc-shaped structure to reduce the deformation of the supporting frame when the bionic flexible fish tail receives lateral pressure. The fastener is connected to the end of the main frame plate away from the tail fin; The flexible fish tail outer skin is disposed on the outer surface of the fixing member and the overall fish tail skeleton, and forms a sealed air chamber with the overall fish tail skeleton. The arrangement of the air chamber ensures that the total weight of the bionic flexible fish tail is equal to the weight of the bionic flexible fish tail after drainage, thereby giving the bionic flexible fish tail the characteristic of neutral buoyancy. The waterproof membrane is disposed on the outer surface of the fastener and the overall fish tail frame, located between the overall fish tail frame and the flexible fish tail skin, and is used to assist in supporting the silicone casting of the flexible fish tail skin and further ensure the airtightness of the air chamber.

2. The biomimetic flexible fish tail with neutral buoyancy according to claim 1, characterized in that, Each of the aforementioned support frames is vertically disposed on two surfaces of the main body of the main frame plate, and each of the aforementioned support frames is disposed perpendicular to the axis of the main frame plate.

3. An underwater biomimetic robotic fish, characterized in that, Includes the biomimetic flexible fish tail with neutral buoyancy and the biomimetic robotic fish body as described in any one of claims 1 to 2; The bionic robotic fish body is connected to the bionic flexible fish tail via a connector, wherein the connector is rotatably connected to the bionic robotic fish body, and the axis of rotation of the connector is perpendicular to the cross section of the bionic robotic fish body, and the connector is fixedly connected to the bionic flexible fish tail.

4. A method for manufacturing a biomimetic flexible fish tail with neutral buoyancy, characterized in that, For fabricating a biomimetic flexible fish tail with neutral buoyancy as described in any one of claims 1 to 2, comprising: Based on a 3D model of a biological fish tail, a biomimetic flexible fish tail main skeleton plate, supporting skeleton and fixing components are made. The main skeleton plate includes a main body and a tail fin. The tail fin is a sickle-shaped structure set at one end of the main body. The multiple supporting frames are divided into two groups, and the two groups of supporting frames are symmetrically installed on two surfaces of the main body, forming a fish tail skeleton with the main frame plate. The fish tail skeleton is installed on the fixing member, and at least one layer of waterproof membrane is wrapped around the outer peripheral surface of the non-tail fin part of the fish tail skeleton to obtain the casting foundation. A fish tail mold was designed based on the 3D model of the described fish tail. The fish tail mold is assembled onto the casting base, and silicone is poured between the fish tail mold and the casting base to form a flexible silicone fish tail skin on the outer circumference of the casting base. After the silicone solidifies, the fish tail mold is removed to obtain a biomimetic flexible fish tail. The weight of the resulting biomimetic flexible fish tail is equal to the total weight of the biomimetic flexible fish tail, which is equal to the weight of the biomimetic flexible fish tail after drainage.

5. The method for manufacturing a biomimetic flexible fishtail with neutral buoyancy according to claim 4, characterized in that, The 3D model based on a biological fish tail is used to fabricate a biomimetic flexible fish tail main skeleton plate, supporting skeleton, and fixing components. The main skeleton plate includes a main body and a tail fin. The tail fin is a sickle-shaped structure located at one end of the main body, including: A 3D model of the fish tail of the organism is established, and the shapes of the main skeleton plate, the supporting skeleton and the fixing components are designed based on the 3D model; The dimensions of the main skeleton plate, the supporting skeleton, and the fixing member are determined based on the material density of the main skeleton plate, the supporting skeleton, the fixing member, and the flexible fish tail outer skin, as well as the design drainage weight of the bionic flexible fish tail. Based on the shape and size of the main frame plate, the supporting frame, and the fixing member, the main frame plate, the supporting frame, and the fixing member are manufactured.

6. The method for manufacturing a biomimetic flexible fishtail with neutral buoyancy according to claim 4, characterized in that, The design of the fish tail mold based on the 3D model of the biological fish tail includes: Based on the 3D model of the fish tail, a first mold, a second mold, and a third mold are designed respectively. The first mold is the mold for the fixing part, the second mold is the mold for the tail fin part, and the third mold is the mold for the main body part.

7. The method for manufacturing a biomimetic flexible fishtail with neutral buoyancy according to claim 6, characterized in that, The process involves assembling the fishtail mold onto the casting foundation, pouring silicone between the fishtail mold and the casting foundation to form a flexible silicone fishtail outer skin on the outer circumference of the casting foundation, and removing the fishtail mold after the silicone has solidified to obtain a biomimetic flexible fishtail. The process includes: The first mold is assembled around the outer periphery of the fixing member of the foundation. After successful assembly, silicone is poured between the first mold and the fixing member until the silicone submerges the nearest opening of the waterproof membrane. After the silicone in the first mold solidifies, the second mold is assembled around the outer periphery of the tail fin on the foundation. After successful assembly, silicone is poured between the second mold and the tail fin until the silicone submerges the nearest opening of the waterproof membrane. After the silicone in the second mold solidifies, the third mold is assembled around the outer periphery of the main body of the foundation. After successful assembly, silicone is poured between the third mold and the main body. After the silicone in the third mold solidifies, the first mold, the second mold, and the third mold are removed together to obtain the biomimetic flexible fish tail.

8. The method for manufacturing a biomimetic flexible fishtail with neutral buoyancy according to any one of claims 4 to 7, characterized in that, Two sets of support frames are symmetrically installed on two surfaces of the main body of the main frame plate using hot melt adhesive, so that the hot melt adhesive can be detached during use of the biomimetic flexible fish tail.

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