Disease-dead fish recovery robot based on variable-direction suction head

Abstract

The invention discloses a dead fish recovery robot based on a turning suction head, belongs to the field of mariculture equipment, and solves the problems of low efficiency, complex structure and high control difficulty of suction type and grabbing type dead fish recovery robots in the prior art. According to the suction catching device, the suction catching mechanism is provided with a suction catching head opening, and the suction catching head opening protrudes out of the machine body; the sucking and catching mechanism comprises a flexible tubular direction-changing sucking and catching head, and the direction-changing sucking and catching head is mounted at the end part of the machine body; a storage bin mechanism is arranged in the machine body and comprises a tubular part, an opening and closing opening is formed in the lower portion of the tubular part, and an opening and closing mechanism is arranged at the opening and closing opening. One end of a tubular part of the storage cabin mechanism is communicated with the turning suction head, and the other end of the tubular part is connected with a negative pressure mechanism. According to the dead fish recovery robot based on the variable-direction suction head, dead fishes can be recovered in time and prevented from further rotting and polluting water quality, meanwhile, the dead fish recovery cost is reduced, the recovery efficiency is improved, and intelligent net cage culture is assisted.

Description

Technical Field

[0001] This invention relates to a robot for recovering diseased and dead fish based on a directional suction head, belonging to the field of marine aquaculture equipment. Background Technology

[0002] In recent years, with the overall transformation of China's fisheries, traditional fishing has been gradually replaced by aquaculture, and aquaculture, represented by cage culture, has developed rapidly, becoming one of the main sources of aquatic products. Currently, however, my country's cage culture industry is mostly concentrated in inland and coastal areas, employing traditional artificial farming methods, which suffers from low production efficiency, severe environmental pollution, and resource depletion. On the one hand, developing cage culture in deep-sea areas can effectively address the problem of limited resources; on the other hand, developing intelligent equipment to support cage culture will significantly reduce production costs and promote transformation. In conclusion, with the gradual application of cage culture, the development of supporting intelligent equipment will greatly improve the level of unmanned and intelligent aquaculture, which is of great significance to the transformation of my country's fisheries.

[0003] During fish farming in net cages, some fish may die due to injury or infection. If not handled promptly, this will pollute the water quality within the cages, affecting the health of the fish and causing economic losses. Currently, the common method for recovering dead fish from net cages is to manually lift the nets, causing the dead fish at the bottom to float to the surface for collection. While this method is effective in handling dead fish, it is inefficient, complex to operate, and wastes significant manpower and resources. Based on the current research status of ROV (Return on Vehicle) underwater capture technologies both domestically and internationally, it can be seen that current capture methods in this field are mainly divided into suction and grabbing methods. Suction methods utilize negative pressure principles for collection, resulting in a simple structure and working principle, high efficiency, easy disassembly and maintenance, and adaptability to harsh environments. However, during operation, it easily sucks in impurities such as seabed sediment and algae, causing blockages and making the water turbid, thus reducing efficiency. Grabbing methods, on the other hand, use multi-degree-of-freedom robotic arms, offering a wide working range and high flexibility, but also resulting in higher control difficulty, lower efficiency, and a complex structure. Summary of the Invention

[0004] This invention provides a dead fish recycling robot based on a directional suction head, which can promptly collect dead fish to prevent further decay and water pollution, while reducing the cost of dead fish recycling, improving recycling efficiency, and facilitating intelligent cage aquaculture.

[0005] The technical solution adopted in this invention is a dead fish recycling robot based on a directional suction head, comprising a body and a suction mechanism; the suction mechanism has a suction head opening that protrudes from the body;

[0006] The suction mechanism includes a flexible tubular deflecting suction head, which is installed at the end of the body;

[0007] The machine body has a storage compartment mechanism, which includes a tubular part, an opening and closing port at the lower part of the tubular part, and an opening and closing mechanism at the opening and closing port.

[0008] One end of the tubular part of the storage compartment mechanism is connected to the directional suction head, and the other end of the tubular part is connected to a negative pressure mechanism.

[0009] The optimized version of the above-mentioned dead fish recycling robot based on the directional suction head has a frame-type main structure.

[0010] The fuselage is equipped with floats and sealed compartments;

[0011] Several thrusters are installed at the ends of the machine body.

[0012] The optimized version of the above-mentioned dead fish recovery robot based on the directional suction head includes several vertical motion thrusters and several horizontal motion thrusters in all its thrusters.

[0013] All horizontal plane motion thrusters are arranged in a cross-vector pattern to prevent misalignment;

[0014] All horizontal propellers are symmetrically arranged and have an angle β with the direction of travel.

[0015] In the optimized version of the above-mentioned dead fish recycling robot based on the directional suction head, the outer diameter of the tubular part gradually decreases from one end closer to the directional suction head to the other end.

[0016] The tubular section includes a fixed plate and two movable plates;

[0017] The fixed plate is located above the moving plate, and the two moving plates are located on the lower sides of the fixed plate, forming a closed pipe with the fixed plate and the two moving plates.

[0018] The lower part of the tubular section is connected to a collecting net; the lower ends of the two moving plates are respectively connected to the two sides of the opening of the collecting net.

[0019] In the optimized version of the above-mentioned dead fish recycling robot based on the directional suction head, the fixed plate is fixed inside the machine body; the two moving plates are each connected to a set of opening and closing mechanisms.

[0020] The middle section of the moving plate is rotatably connected to the machine body via a rotating shaft; the opening and closing mechanism drives the moving plate to rotate around the rotating shaft and pushes the opening of the collection net to both ends to open it.

[0021] The optimized version of the above-mentioned dead fish recycling robot based on the directional suction head has a multi-link mechanism for opening and closing, which includes an active link and a driven link. One end of the driven link is hinged to the end of the active link, and the other end of the driven link is hinged to the lower end of the moving plate. An opening and closing motor is hinged to the end of the active link away from the driven link, and the opening and closing motor is fixed relative to the body.

[0022] The optimized version of the dead fish recycling robot based on the directional suction head described above has a directional suction head that is a line-driven continuous flexible tube with several drive lines connected to a drive module.

[0023] The optimized version of the above-mentioned dead fish recycling robot based on the directional suction head includes at least one joint segment in the directional suction head.

[0024] The joint segment includes several annular discs, and there are elastic hoses between adjacent annular discs. The ends of the elastic hoses are sealed and fixed to the annular discs.

[0025] Each joint segment has several drive lines; the drive lines pass through the entire annular disc of the joint segment; one end of the drive line is fixed to the annular disc at the end of the joint segment away from the body, and the other end of the drive line is connected to the power output end of the drive module.

[0026] In the optimized version of the above-mentioned dead fish recycling robot based on the directional suction head, the flexible hose is a polymer resin hose with a spiral spring steel wire embedded inside; the central axis of the spiral of the spring steel wire embedded in the flexible hose is coaxial with the flexible hose.

[0027] All driving lines of the joint segment are evenly spaced around the joint segment.

[0028] The optimized, above-mentioned dead fish recycling robot based on the directional suction head has a drive module that includes several twisted wire motors, with each drive line equipped with a twisted wire motor, and the power output end of the twisted wire motor has a twisted wire wheel;

[0029] The end of the drive line away from the direction-changing suction head is wound around the stranded reel, and the rotation of the stranded reel is converted into a change in the length of the drive line.

[0030] The advantages of this application are:

[0031] The flexible underwater movement capability of this application ensures that the robot can smoothly complete underwater navigation and approach targets. Its efficient recovery capability ensures that the robot can successfully capture targets in various environments and under various obstacles. Sufficient storage capacity ensures that the robot can carry a sufficient number of targets in a single operation, avoiding repeated dives and increasing recovery costs. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of this application;

[0033] Figure 2 A schematic diagram of the thruster arrangement;

[0034] Figure 3 This is a schematic diagram of an openable storage compartment;

[0035] Figure 4-1 This is a schematic diagram of the opening;

[0036] Figure 4-2 Schematic diagram of the opening and closing scheme of a four-bar linkage

[0037] Figure 5 This is a schematic diagram of the directional suction head of this application;

[0038] Figure 6 This is a schematic diagram of the basic structure of the stranding wheel in this application;

[0039] Figure 7 This is a schematic diagram of the strand wheel shaft system installation structure of this application;

[0040] Figure 8 This is a schematic diagram of the opening mechanism for the openable storage compartment. Detailed Implementation

[0041] The technical features of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] This application discloses a device for recovering diseased and dead fish used in aquaculture cages, the overall structure of which is as follows: Figure 1 As shown. The overall structure adopts a frame-type main structure with a six-propeller vector arrangement. The front end is equipped with a variable-direction suction head, the middle section is an openable storage compartment with a fishing net installed underneath, and the rear end has a negative pressure device. It also includes a sealed compartment, a float, and other basic components. During retrieval, the robot first moves to the vicinity of the target object using its propellers. The suction head moves to the front or rear of the fish. Then, the negative pressure device activates, causing the fish to enter the openable storage compartment along the pipe. The openable storage compartment opens, allowing the fish to enter the lower collection net. Finally, the openable storage compartment closes, shutting off the net and completing the retrieval task.

[0043] As shown in the figure, the present application discloses a robot for recovering dead fish based on a directional suction head, which includes a body 1 and a suction mechanism.

[0044] The main body 1 is a frame-type structure. A float 4 and a sealed chamber 5 are mounted on the main body 1. Since the working environment is underwater, the structural form of the robot in this application has a significant impact on its stability, structural strength, and other performance characteristics.

[0045] Existing frame structures are typically assembled from basic profiles such as profiles and plates. Various working modules are arranged on the frame structure as required, and the control module is placed in a special watertight chamber and installed in the central area of ​​the frame.

[0046] The frame structure occupies a small portion of the space, improving the robot's space utilization and facilitating the mounting of various end effectors. However, since each module is directly exposed underwater, the robot's hydrodynamic performance is significantly reduced, but at the same time, its motion stability is improved. Frame structures are commonly used in operational underwater robots to facilitate the mounting of various execution devices. Considering the above factors, and taking into account the task requirements and working environment of the recovery robot, the technical solution in this application adopts a frame structure.

[0047] For frame structures, this application can adopt a plate frame structure, which is made of composite material plates connected by metal bolts, angle irons, slots, etc., which is lightweight while ensuring basic strength requirements.

[0048] In this embodiment, a plurality of thrusters 6 are mounted on the end of the body 1. All thrusters 6 include a plurality of vertical plane thrusters and a plurality of horizontal plane thrusters. All horizontal plane thrusters are arranged in a mutually intersecting vector arrangement. All horizontal plane thrusters are symmetrically arranged and form an angle β with the direction of travel.

[0049] Motion capability is fundamental for underwater robots to perform tasks, and the number and arrangement of thrusters determine the robot's motion performance, such as speed and degrees of freedom. Underwater robots possess three translational and three rotational degrees of freedom. The three translational degrees of freedom are forward / backward, lateral, and heave; the three rotational degrees of freedom are roll, pitch, and yaw.

[0050] In principle, underwater robots require at least three degrees of freedom: heave and yaw to enable diving and recovery in the water depth direction, and forward / backward and yaw to enable movement in the horizontal plane. These three degrees of freedom ensure that the underwater robot can reach any position in space, and this can be achieved using three thrusters. However, too few thrusters will lead to insufficient thrust and poor motion performance. Increasing the number of thrusters can improve the robot's maneuverability and flexibility. Considering the task requirements of the robot in this application, the robot only needs to have forward / backward, lateral, and yaw degrees of freedom in the horizontal plane, and heave and yaw degrees of freedom in the vertical plane. Furthermore, considering the robot's motion flexibility and load capacity requirements, the technical solution in this application can choose to use six thrusters.

[0051] The layout design of the robot's thrusters in this application needs to take the following points into consideration:

[0052] The combined forces of the 1 thrusters converge at a single point, and this point is made as close as possible to the center of gravity of the machine to prevent torque from causing additional motion.

[0053] 2. Avoid water flow obstruction in the thrust direction of the propeller to reduce the thrust magnitude.

[0054] 3. Consider the pairing of forward and reverse propellers to avoid the reaction force couple of the propeller rotating on the fuselage, which would affect...

[0055] The robot's posture.

[0056] 4. The thrusters should be placed as low as possible on the robot, but avoid the influence of mud and sand at the bottom of the water.

[0057] In a six-thruster arrangement, typically four are used for horizontal motion and two for vertical motion. For the four horizontal thrusters, there are two layout options: a vertical arrangement with two thrusters arranged perpendicularly to each other, and a vector arrangement with thrusters intersecting each other, such as... Figure 2 The schematic diagram of the thruster arrangement is shown. In the vertical arrangement, the two main thrusters are located on either side of the robot, achieving forward and backward freedom. The two lateral thrusters are located on the front and rear end faces, achieving lateral movement freedom. Yaw is achieved by providing equal and opposite thrust from opposing thrusters. While the vertical arrangement offers a simple thrust distribution strategy, the thruster utilization rate is low, as only two thrusters are used for forward, backward, and lateral movement.

[0058] The vector thruster scheme arranges four thrusters symmetrically, maintaining an angle β with the forward direction. Horizontal movement is achieved through the distribution of thrust from each thruster. A smaller angle β results in a larger maximum thrust in the forward and backward directions; β is typically taken as 20°–45°. Ultimately, considering the higher thrust requirements for the robot in the forward and backward directions in this application, a vector thruster method is adopted, with an angle β of 30 degrees.

[0059] In this embodiment, the storage compartment mechanism is installed inside the frame of the body 1. The storage compartment mechanism includes a tubular section, the lower part of which has an opening and closing port, and the opening and closing port has an opening and closing mechanism.

[0060] One end of the tubular part of the storage compartment mechanism is connected to the directional suction head 2, and the other end of the tubular part is connected to the negative pressure mechanism 3.

[0061] The tubular section includes a fixed plate 601 and two movable plates 602. The fixed plate 601 is located above the movable plates 602, and the two movable plates 602 are located on both sides below the fixed plate 601, forming a closed pipe. A collection net 603 is connected to the lower part of the tubular section, and the lower ends of the two movable plates 602 are connected to the openings on both sides of the collection net 603.

[0062] Several parallel, spaced-apart fixed plates are installed within the frame structure of the body 1. After the lower end of the fixed plate is slotted, the fixed plate 601 is fixedly installed in the slot of the fixed plate. The movable plate 602 is hinged to the fixed plate via a rotating shaft.

[0063] For collecting underwater organisms, nets are often used to reduce the added mass of water and minimize the load on the power unit. However, underwater capture robots using negative pressure suction systems require a storage compartment positioned between the front suction port and the rear negative pressure device because the target cannot pass through the power unit. To transfer the negative pressure generated by the negative pressure device to the suction port, the storage compartment must be designed as a closed structure to prevent internal flow leakage and capture failure. To facilitate the spatial arrangement of the storage compartment and improve space utilization, the closed storage compartment is often a regular cuboid shape, with openings at the front and rear for the suction port pipes connecting to the negative pressure device.

[0064] The outlet is typically positioned on the upper side to prevent bottom sediment from being sucked into the negative pressure device, and a filter screen is installed at the outlet. After the target material travels from the suction port along the pipe to the storage chamber, it settles at the bottom of the storage chamber under gravity. This design, due to the sealed interior of the storage chamber, significantly increases the added mass of the robot's movement, affecting its overall motion performance. Furthermore, during suction, the abrupt change in the cross-section of the storage chamber causes significant localized losses, increasing the power consumption of the negative pressure device and reducing recovery efficiency. For the salmon to be recovered in this application, which is relatively large, this design would also significantly increase the volume of the storage chamber, occupying considerable internal space within the robot. Considering all these factors, this application proposes an openable storage chamber design, using this openable storage chamber to transfer the captured material to a net at the bottom of the robot, as shown in the specific structure below. Figure 3 As shown.

[0065] The storage chamber is basically tubular, composed of three arc-shaped tubes cut into thirds along its longitudinal direction. The topmost tube is a fixed plate, while the two side tubes are movable plates that can rotate along a pivot. The bottom is a collection net, with the openings on either side connected to the bottom of the two movable plates. The storage chamber has two states: a closed suction state and an open transfer state. In the closed state, fish flow into the storage chamber tube along the pipes, and the net openings are closed. Then, it transitions to the open transfer state, the net openings open, and the fish enter the collection net under gravity. Finally, it returns to the closed state, and the net openings close.

[0066] The cylindrical structure of the storage compartment is adapted to the slender body shape of fish, greatly improving space utilization. It also helps to constrain the fish's posture, ensuring they are positioned forward or backward within the compartment, resulting in a more orderly arrangement of fish after entering the collection net and further enhancing space utilization. Furthermore, the use of tapered tubes at cross-sectional changes in the cylindrical structure further reduces local losses in the fluid system.

[0067] In this application, each of the two movable plates 602 is connected to a set of opening and closing mechanisms. Specifically, the middle section of the movable plate 602 is rotatably connected to the body 1 via a rotating shaft. The opening and closing mechanisms drive the movable plate 602 to rotate around the rotating shaft and push the opening of the collection net 603 to both ends to open it.

[0068] In this embodiment, the opening and closing mechanism is a multi-link mechanism, which includes a driving rod 604 and a driven rod 605. One end of the driven rod 605 is hinged to the end of the driving rod 604, and the other end of the driven rod 605 is hinged to the lower end of the moving plate 602. An opening and closing motor is hinged to the end of the driving rod 604 away from the driven rod 605, and the opening and closing motor is fixed relative to the body 1.

[0069] The key to designing the opening and closing mechanism lies in how to achieve the required opening size within a limited space, while also possessing good mechanical properties and stable operation in the underwater environment. Given the maximum cross-sectional dimension of the fish (120mm), the maximum opening size is set at 130mm to ensure the fish can fall smoothly into the net and prevent fish at the bottom from entering the storage compartment due to water currents. Two opening schemes are analyzed: direct-acting and rotating opening. With the direct-acting scheme, the moving plate can open and close by translation, a simple motion. However, it requires linear guides and corresponding transmission structures at the component level. Considering the minimum opening size should be 120mm, the overall component size of the direct-acting scheme is relatively large, which is not conducive to installation. For the rotating opening scheme, the opening is achieved by the moving plate rotating around an axis. The opening size mainly depends on the rotation angle and radius, allowing for a larger opening within a limited space. From a component level perspective, bearings and rotating parts are required. By analyzing the specific structural forms of each scheme applied to this robot, considering the large axial length of the moving plate, the sweeping volume of the moving plate during the movement of the linear motion scheme is much larger than that of the rotary motion scheme. At the same time, considering the limitation of the lateral dimension of the machine body, the rotary motion scheme is adopted.

[0070] For rotary motion schemes, the main considerations are the position of the rotation axis and the rotary transmission scheme. The position of the rotation axis primarily affects the size of the opening, such as... Figure 4-1As shown, the distribution area of ​​the rotating shaft can be divided into two parts by a line of symmetry: above and below the line of symmetry. When the rotating shaft is located below the line of symmetry, the largest opening occurs at the point where the upper edges of the two moving plates collide. Since the moving plates are symmetrically arranged, the collision point is located on the plane of symmetry, and the distance between the lower edges of the two plates is the size of the opening. Analysis shows that the closer the rotating shaft is to the lower end face, the smaller the rotation angle and the smaller the lower rotation radius, resulting in a smaller opening. When the rotating shaft is above the line of symmetry, due to geometric relationships, the upper end will not reach the plane of symmetry, and the rotation angle is not limited by collision interference. The largest opening occurs when the tangent of the arc at the lower end of the moving plate is perpendicular to the horizontal plane. Analysis shows that the closer the rotating shaft is to the upper section, the larger the opening. However, since the upper surfaces of the two moving plates cannot close, during movement, the fish inside the hull may leak along the upper edge gap and get stuck in the upper area. Considering all these factors, the rotating shaft is placed on the dividing line, with a minimum distance of 10mm from the outer circle of the tube to prevent interference from parts on the shaft. Using the above method for determining the opening size, the required rotation angle is 60 degrees.

[0071] Based on the operational requirements of the robot in this application, such as Figure 4-2 As shown, this application ultimately adopts a four-bar linkage as the transmission structure. Compared to other existing solutions, the dead-point principle of the four-bar linkage is utilized in the closed state, ensuring that the motor is not subjected to continuous torque. Furthermore, given that the axial dimension of a four-bar linkage is often small, the bending moment caused by radial force on the motor shaft can be ignored. Taking all factors into consideration, the four-bar linkage solution was chosen.

[0072] The structural design of a four-bar linkage mainly involves the lengths of each link and the specific position of the fixed shaft. First, the length of the driven link is determined. Given the position of the driven link's rotation axis, its length depends on the installation position of the hinge at the other end. Force analysis is performed in the open state shown in Figure 4-1. To ensure that the downward vertical force exerted by the collecting net at the opening is primarily transmitted to the fixed shaft, thus reducing the motor load, theoretically, the driven link should be kept as vertical as possible to bear a larger portion of the tension. Therefore, based on the closed state, the downward vertical line is rotated 60 degrees counterclockwise around the fixed shaft. The position where this line intersects the moving plate is the reference position. Adjustments are made according to the actual structure to complete the design of the driven link.

[0073] Secondly, the position of the servo shaft was determined. Considering the servo installation location and the range of motion of the four-bar linkage, the position of the servo shaft was selected as 50mm horizontally shifted to both sides of the driven shaft. Then, the lengths of the connecting rod and the driving rod were designed based on the dead-point principle. The final length of the driving rod was 30mm, and the connecting rod length was 81.35mm. In summary, the structural parameters of the four-bar linkage are shown in Table 4-1.

[0074] Table 4-1 Structural parameters of a four-bar linkage

[0075]

[0076] The suction mechanism has a suction head opening that protrudes from the body 1. The suction mechanism includes a flexible tubular deflecting suction head 2, which is mounted at the end of the body 1. The deflecting suction head 2 is a line-driven continuous flexible tube, and has several drive lines 201 connected to a drive module.

[0077] The deflecting suction head 2 includes at least one joint segment. In this embodiment, to accommodate usage requirements, two joint segments are provided.

[0078] The joint segment includes several annular discs 202, and there are elastic hoses 203 between adjacent annular discs 202. The ends of the elastic hoses 203 are sealed and fixed to the annular discs 202.

[0079] Each joint segment has several drive lines 201, which pass through all the annular discs 202 of the joint segment. One end of the drive line 201 is fixed to the annular disc 202 at the end of the joint segment away from the body 1, and the other end of the drive line 201 is connected to the power output end of the drive module. All the drive lines 201 of the joint segment are evenly spaced around the joint segment.

[0080] The flexible hose 203 is a polymer resin hose with a spiral spring steel wire embedded inside; the central axis of the spiral of the spring steel wire embedded in the flexible hose 203 is coaxial with the flexible hose 203.

[0081] The drive module includes several stranded wire motors, with each drive wire 201 equipped with one stranded wire motor. The power output end of the stranded wire motor has a stranding wheel. The end of the drive wire 201 away from the direction-changing suction head 2 is wound around the stranding wheel, and the rotation of the stranding wheel is converted into a change in the length of the drive wire 201.

[0082] This application employs a spring-supported, wire-driven suction head reversal scheme. The spring acts as the outer ring of the suction tube, providing support and ensuring sufficient internal space. Connecting discs are installed at equal intervals, and the driving force generated by the bottom drive module is transferred to the connecting discs via wire drive, achieving reversal. Furthermore, since the suction tube must be completely sealed, the spring is embedded in a flexible material, giving the outer wall both elastic support and a sealing function.

[0083] The steering head module mainly consists of a suction tube, a fixing plate, and a pull rope. The suction tube requires an embedded spring for elastic support. Specific design details include the suction tube's inner diameter, length, number of joints, and material selection. The inner diameter of the suction tube determines the maximum radial dimension of the fish that can pass through; the length and number of joints determine the robot's workspace and movement flexibility; and the material selection determines the overall rigidity of the suction tube and the driving force required for deformation.

[0084] The fish's maximum radial dimension is 120mm, therefore the suction nozzle size should be greater than 120mm. However, considering the precision of nozzle positioning and interference from the external environment, the nozzle may not be perfectly aligned with the fish's axis, so the inner diameter of the suction tube cannot be too small. Furthermore, when the suction tube bends, the fish may get stuck at a corner, requiring a sufficiently large inner diameter for the nozzle. However, an excessively large nozzle would further increase the power consumption of the negative pressure device, thus reducing suction efficiency. Taking all these factors into account, the final design for the nozzle inner diameter is 150mm.

[0085] The design of the suction tube length and number of joints primarily depends on the complexity of the working environment. When the fish is in a narrow and complex area, the robot body cannot approach and can only enter through the suction head at the front end to complete the retrieval. Therefore, the longer the suction tube and the more joints, the larger the robot's retrieval workspace and the more flexible its movement. However, as the suction tube length increases, the robot's center of gravity shifts forward, further increasing water resistance during movement, increasing power consumption, and the increased number of joints also increases control difficulty. Ultimately, based on the aforementioned functional indicator requirement of a 0.85m retrieval workspace, twice the length of the fish was chosen as the suction tube length, i.e., 1m. Simultaneously, to fully utilize the advantages of the continuous robot's good flexibility and strong environmental adaptability, joints are placed in the middle of the length, resulting in two joints and two segments: segment I closer to the base and segment II further away. Each segment is divided into three sub-segments by a fixed connecting plate. Each sub-segment is secured by three ropes connected to the root drive module and sequentially passes through pre-drilled holes on the fixed plate, serving a constraint function. Figure 5 As shown.

[0086] Because the straw requires a spring to be embedded within the flexible tube wall, the structure is relatively complex. A survey of existing products on the market revealed a steel wire flexible tube, which incorporates steel wires into a polyurethane flexible tube, giving it flexible expansion and contraction resistance. With a wide range of models available, this design was ultimately chosen. The structural design of the fixing plate needed to consider how it would be fixed to the straw. Since the outer wall of the tube has a spiral structure, a slightly smaller internal thread structure was designed on the inner wall of the fixing plate. It is also divided into two halves along a plane of symmetry. During installation, a boss is designed at the interface between the two halves, and bolts and nuts are used for fastening. The flexible nature of polyurethane material is utilized, with the tension force generated by its deformation providing the fixation.

[0087] The drive module primarily converts the rotational motion of the motor shaft into a change in the length of the rope via a winch, thereby causing deformation of the front-end continuous robot. The design mainly includes the structural design of the winch and drive shaft, and the selection of the drive motor. The winch rotates to pull and release the rope; its basic structure is as follows... Figure 3-6 As shown, the main structural parameters include the bottom diameter, groove height, groove width, and center hole diameter. The bottom diameter determines the rate of change of rope length, the groove height and groove width together determine the range of rope length change, the center hole diameter depends on the outer diameter of the central shaft, and the top diameter determines the torque exerted by the rope tension on the drive shaft.

[0088] When determining the assembly scheme, the assembly scheme for the parts on the shaft is first drafted. The main load-bearing component on this shaft system is the winch. Based on the installation sequence of the components on the shaft system and the structural strength and rigidity of the shaft, the following assembly scheme is adopted: Figure 7 The installation scheme shown employs a double-support, unidirectional fixed support design for the bearing, which improves the rigidity and strength of the shaft.

[0089] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should be protected by the present invention.

Claims

1. A dead fish recovery robot based on a reversible suction head, comprising a body (1) and a suction mechanism; the suction mechanism has a suction head opening, the suction head opening protruding from the body (1); characterized in that: The suction and capture mechanism comprises a flexible tubular reversible suction and capture head (2), which is installed at the end of the machine body (1); The machine body (1) has a storage compartment mechanism, which comprises a tubular portion, an opening and closing opening is constructed at the lower portion of the tubular portion, and an opening and closing mechanism is provided at the opening and closing opening; One end of the tubular portion of the storage compartment mechanism is connected to the direction-changing suction head (2), and the other end of the tubular portion is connected to the negative pressure mechanism (3).

2. The dead fish recovery robot based on the reversible suction head according to claim 1 is characterized in that: The machine body (1) is a frame-type main structure; A floating body (4) and a sealed cabin (5) are installed on the body (1); A plurality of propellers (6) are installed at the end of the machine body (1).

3. The dead fish recovery robot based on the reversible suction head according to claim 2 is characterized in that: The total number of propellers (6) includes a plurality of vertical plane motion propellers and a plurality of horizontal plane motion propellers; All horizontal plane motion thrusters are arranged in mutually intersecting vectors to prevent the arrangement; All horizontal plane motion thrusters are arranged symmetrically and have an angle β with the forward direction.

4. The dead fish recovery robot based on the reversible suction head according to claim 2 is characterized in that: The outer diameter of the tubular portion gradually decreases from one end close to the direction-changing suction catcher (2) to the other end; The tubular portion includes a fixed plate (601) and two movable plates (602); The fixed plate (601) is located above the movable plate (602), and the two movable plates (602) are respectively located on both sides below the fixed plate (601), and the fixed plate (601) and the two movable plates (602) form a closed pipeline; The lower part of the tubular part is connected to a collecting net bag (603); the lower ends of the two movable plates (602) are respectively connected to the two sides of the opening of the collecting net bag (603).

5. The dead fish recovery robot based on the reversible suction head according to claim 4 is characterized in that: The fixed plate (601) is fixed in the machine body (1); the two movable plates (602) are respectively connected to a set of opening and closing mechanisms; The middle section of the movable plate (602) is rotatably connected to the machine body (1) via a rotating shaft; the opening and closing mechanism drives the movable plate (602) to rotate around the rotating shaft and pushes the opening of the collection net bag (603) toward both ends to open.

6. The dead fish recovery robot based on the reversible suction head according to claim 5 is characterized in that: The opening and closing mechanism is a multi-link mechanism, comprising an active rod (604) and a driven rod (605); one end of the driven rod (605) is hinged to the end of the active rod (604), and the other end of the driven rod (605) is hinged to the lower end of the moving plate (602); an opening and closing motor is hinged to one end of the active rod (604) away from the driven rod (605), and the opening and closing motor is relatively fixed to the machine body (1).

7. The dead fish recovery robot based on a reversible suction head according to claim 1 is characterized in that: The direction-changing suction head (2) is a line-driven continuous flexible tube. The direction-changing suction head (2) has a plurality of driving lines (201), and the driving lines (201) are connected to driving modules.

8. The dead fish recovery robot based on the reversible suction head according to claim 7 is characterized in that: The direction-changing suction head (2) comprises at least one joint segment; The joint section comprises a plurality of annular disc bodies (202), and an elastic hose (203) is provided between adjacent annular disc bodies (202), and the end of the elastic hose (203) is sealed and fixed to the annular disc body (202); Each joint segment has a plurality of drive lines (201); the drive lines (201) pass through all the annular disc bodies (202) of the joint segment; one end of the drive line (201) is fixed to the annular disc body (202) at one end of the joint segment away from the body (1), and the other end of the drive line (201) is connected to the power output end of the drive module.

9. The dead fish recovery robot based on the reversible suction head according to claim 8 is characterized in that: The elastic hose (203) is a polymer resin hose with a spiral spring steel wire embedded inside; the central axis of the spiral line of the spring steel wire embedded in the elastic hose (203) is coaxial with the elastic hose (203); All the driving lines (201) of the joint segment are evenly spaced around the joint segment.

10. The dead fish recovery robot based on the reversible suction head according to claim 7 is characterized in that: The driving module comprises a plurality of twisting wire motors, each driving wire (201) is provided with a twisting wire motor, and the power output end of the twisting wire motor has a twisting wire wheel; One end of the driving wire (201) away from the direction-changing suction head (2) is wound around a wire twisting wheel, and the rotation of the wire twisting wheel is converted into a change in the length of the driving wire (201).

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