Underwater towed body swinging device based on SMA (Shape Memory Alloy)

Abstract

The utility model belongs to the technical field of underwater robots, and particularly discloses an underwater towed body swinging device based on SMA. The underwater towed body swinging device mainly comprises a towed body, a control unit, an edge swinging device and a middle swinging device, the control unit mainly comprises a main control board, and the edge swinging device and the middle swinging device are each provided with a swinging arm; according to the device disclosed by the utility model, the SMA driver is arranged in the swinging arm by utilizing the characteristic that the SMA wire is bent after being heated, current signals are transmitted to the side swinging devices and the middle swinging device through the main control board, and the swinging arm is driven to swing by adopting a current heating method, so that the advancing posture of the towed body is adjusted; according to the device, the steel sheet is selected as a springback part of the SMA driver, the springback effect of the swing arm can be improved, it is ensured that the SMA wire can be normally bent during current heating, and rapid springback after bending can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of underwater robots, in particular to an underwater towing body swinging device based on SMA. Background Art

[0002] The underwater towed body swing device is a device used for underwater control and manipulation, and is usually used in the fields of underwater robots, underwater detectors and underwater tools. They can generate propulsion through swinging motion to achieve directional movement and manipulation in underwater environments. When the towed body is working underwater, the speed of the hull itself will be transmitted to the towed body through the cable, so that the towed body will receive an oblique upward force. The upward force will gradually deviate from the towed body and no longer work in the horizontal direction, which may cause deviations in the data collected when the towed body is working. In addition, due to the complex seabed environment, various reefs are randomly distributed in the sea, and the hull may hit a reef when it moves forward by dragging the towed body through the cable. Therefore, the towed body is required not only to maintain its own balance during the normal speed of the ship, but also to generate propulsion through swinging motion to avoid hitting a reef or sinking to the bottom of the sea.

[0003] At present, the design and application of existing underwater towing body swinging devices are generally based on traditional hydraulic or electric drive systems, which generate propulsion force by controlling the movement of the swing arm through a transmission mechanism. However, these traditional underwater towing body swinging devices are generally complex in structure, large in size and weight, and have relatively high energy consumption during operation. Therefore, it is necessary to improve the existing underwater towing body swinging devices. Utility Model Content

[0004] The utility model aims to provide an underwater towing body swinging device based on SMA, which has a simple structure, low energy consumption and can adjust its posture by its own swing to keep the device balanced.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] An underwater towing body swinging device based on SMA, comprising a towing body;

[0007] A control unit is provided inside the trailer, and the control unit includes a main control board;

[0008] Side swingers are arranged on both sides of the towing body, and the side swingers include a first connecting seat and a first swing arm; the first connecting seat is fixedly connected to the side wall of the towing body, one end of the first swing arm is inserted into the inside of the first connecting seat, and the first swing arm is arranged horizontally;

[0009] A groove is provided at the middle position of the top of the towing body, and a middle swinger is arranged in the groove, and the middle swinger includes a second connecting seat and a second swing arm; the second connecting seat is connected to the side wall of the groove, the second swing arm is connected to the second connecting seat, and the second swing arm is arranged vertically;

[0010] The first swing arm and the second swing arm have the same internal structure, and both use an SMA driver and a steel sheet for realizing the recovery deformation of the SMA driver;

[0011] The main control board is connected to the SMA driver via a data cable.

[0012] Preferably, the SMA driver comprises a PCB board and an SMA wire;

[0013] Wherein, a PCB board is symmetrically arranged at both ends of the SMA actuator, and a plurality of through holes are opened at corresponding positions of the two PCB boards, and the spacing between adjacent through holes is equal;

[0014] The SMA wires are passed through the through holes at corresponding positions on the two PCB boards and tightened, and the SMA wires are parallel to each other with gaps left;

[0015] The main control board is connected to the PCB board via a data cable;

[0016] The SMA actuator was encapsulated with PDMS.

[0017] Preferably, the steel sheet is bonded to the back surface of the SMA actuator by waterproof adhesive, and is encapsulated together with the SMA actuator as a whole by PDMS.

[0018] Preferably, a sonar sensor is provided on the main control board.

[0019] Preferably, an inclination sensor is further provided inside the trailer body, and the inclination sensor is connected to the main control board via a data cable.

[0020] Preferably, a battery is also provided on the trailer body, and the battery is connected to the control unit, the side swinger and the middle swinger via a data cable.

[0021] Preferably, in the edge swinger, two groups of first swing arms are provided on the first connecting seat.

[0022] Preferably, the first connecting seat is fixed to the towing body by bolts.

[0023] Preferably, the thickness of the steel sheet is 0.6 mm.

[0024] The beneficial effects of the utility model are as follows:

[0025] The utility model proposes an underwater towing body swinging device based on SMA. By utilizing the characteristic of SMA wire bending under heat, the SMA wire is arranged in the first swing arm and the second swing arm, and the current signal is transmitted to the side swinger and the middle swinger through the main control board. The first swing arm and the second swing arm are driven to swing by the current heating method, so as to adjust the traveling posture of the towing body. The utility model device uses steel sheets as the rebound component of the SMA driver, which can improve the rebound effect of the swing arm, ensure that the SMA wire can bend normally when heated by current, and can also achieve rapid rebound after bending.

[0026] In addition, the interior of the towed body is also equipped with an inclination sensor and a sonar sensor, which are used to determine whether the towed body is moving in a horizontal direction and detect and identify underwater reefs. The sensor transmits data to the main control board, which transmits electrical signals to the SMA driver. The SMA wire is bent by heat, driving the swing arm to swing, ensuring the normal movement of the towed body.

[0027] It is particularly noteworthy that, because the towed body operates in an underwater environment, the heat released by the SMA wire can be quickly absorbed by the water in the surrounding environment, which can effectively reduce the temperature of the SMA actuator, thereby improving the stability and performance of the SMA actuator. Therefore, in an underwater environment, the actuator made based on SMA wire not only has an efficient driving function, but also has excellent heat dissipation performance, which provides a guarantee for the stable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional diagram of the utility model;

[0029] Figure 2 It is a top view of the utility model;

[0030] Figure 3 It is a side view of the utility model;

[0031] Figure 4 The internal structure of the utility model is shown in FIG. Figure 1 ;

[0032] Figure 5 The internal structure of the utility model is shown in FIG. Figure 2 ;

[0033] Figure 6 The internal structure of the utility model is shown in FIG. Figure 3 ;

[0034] Figure 7 It is a structural schematic diagram of the edge oscillator of the utility model;

[0035] Among them, 1-drag body, 11-groove;

[0036] 2- Main control board;

[0037] 3-side swinger: 31-first connecting seat, 32-first swing arm, 321-PCB board, 322-SMA wire;

[0038] 4- middle swinger: 41- second connecting seat, 42- second swing arm;

[0039] 5-Sonar sensor, 6-Tilt sensor. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0041] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] Combination Figures 1 to 7 As shown, the utility model proposes an underwater towing body swinging device based on SMA, including a towing body 1, a control unit, a side swinger 3 and a middle swinger 4 and other structural components

[0043] Combination Figures 4 to 6 As shown, a control unit is arranged inside the trailer body 1, and the control unit mainly comprises a main control board 2, which is mainly used to control the deformation of the SMA driver in the side oscillator 3 and the middle oscillator 4, and to receive and process the signals detected by the sonar sensor 5 and the inclination sensor 6.

[0044] Combination Figures 1 to 3 As shown, the side swingers 3 are arranged on both sides of the towing body 1, and two sets of side swingers 3 are arranged on each side, and the two sets of side swingers 3 on the same side are arranged in a front-to-back manner. The side swinger 3 mainly includes a first connecting seat 31 and a first swing arm 32. The first connecting seat 31 is fixedly connected to the side wall of the towing body 1 by bolts, and one end of the first swing arm 32 is inserted into the inside of the first connecting seat 31. When the towing body 1 is kept as a whole as Figure 3When the first swing arm 32 is in a horizontal motion posture and the SMA driver does not bend and deform, the first swing arm 32 is horizontally arranged. Among them, two sets of first swing arms 32 are arranged on each first connecting seat 31, and the first swing arms 32 are flush with each other, so that greater propulsion force can be generated when swinging.

[0045] Combination Figure 1 , Figure 2 and Figure 5 As shown, a groove 11 is provided at the middle position of the top of the trailer body 1, and a middle swinger 4 is arranged in the groove 11. The middle swinger 4 includes a second connecting seat 41 and a second swing arm 42. Figure 5 As shown, the second connection seat 41 is connected to the side wall of the groove 11, and the second swing arm 42 is connected to the second connection seat 41. Figure 3 When the towing body 1 is in a horizontal motion posture and the SMA driver does not bend and deform, the second swing arm 42 is vertically arranged. When the towing body 1 needs to adjust the inclination angle or turn, the posture of the towing body 1 can be flexibly adjusted by selectively adjusting the first swing arm 32 or the second swing arm 42.

[0046] The first swing arm 32 and the second swing arm 42 have the same internal structure, both using an SMA driver and a steel sheet for realizing the SMA driver to restore deformation, and the steel sheet is arranged on the back surface of the SMA driver through waterproof glue. The main control board 2 is connected to the SMA driver through a data cable to control the deformation of the SMA driver, thereby driving the first swing arm 32 and the second swing arm 42 to swing.

[0047] Combination Figure 7 As shown, the SMA driver mainly includes a PCB board 321 and an SMA wire 322. Among them, a PCB board 321 is symmetrically arranged at both ends of the SMA driver, and the PCB board 321 is connected to the main control board 2 through a data cable. A plurality of through holes are provided at the corresponding positions of the two PCB boards 321, and the spacing between adjacent through holes is equal. The SMA wire 322 passes through the through holes at the relative positions on the two PCB boards 321 and is tightened, and the SMA wires 322 are parallel to each other and leave gaps. The SMA wire 322 connects the PCB boards at both ends of the SMA driver and casts them with PDMS. After the casting solidifies, a steel sheet with a thickness of 0.6 mm is fixed behind it with waterproof glue to form the main part of the SMA driver, and the steel sheet and the SMA driver are packaged with PDMS as a whole. Among them, the utility model adopts a steel sheet as the rebound component of the SMA driver, which can improve the rebound effect of the swing arm, ensure that the SMA wire 322 can be normally bent when heated by electric current, and can achieve rapid rebound after bending.

[0048] The SMA wire used in the utility model is an alloy material with superelasticity and shape memory properties. The SMA wire 322 bends when heated and returns to its original shape after cooling. At the same time, since there is a certain gap between each SMA wire 322, and the towing body 1 is in an underwater working environment, the surrounding water source can absorb more heat, and the outside of the entire swing arm is surrounded by water, the SMA driver can dissipate the heat well, which is of great help to the subsequent rapid cooling of the SMA wire 322.

[0049] The utility model adopts PDMS (polydimethylsiloxane, also known as dimethyl silicone oil) casting, which has the appearance of colorless, transparent and extremely high viscosity liquid or silica gel, is odorless, highly transparent, and has the advantages of heat resistance, cold resistance, small viscosity change with temperature, waterproofness, small surface tension and good thermal conductivity. PDMS is used to cast and wrap related lines and swing arms, so that the side swinger 3 and the middle swinger 4 have good waterproof and corrosion resistance.

[0050] Combination Figure 6 As shown, the main control board 2 is provided with a sonar sensor 5 which can be used to detect and identify underwater objects.

[0051] When the ship is towing the towing body 1 by the cable, the towing body 1 may be in danger of running aground due to the complex seabed environment, which is randomly filled with uneven reefs. When there are reefs in front or the underwater towing body 1 is about to run aground, the sound wave signal emitted by the sonar sensor 5 can detect and identify the underwater reefs, and then transmit the data to the main control board 2 in the control unit. The main control board 2 receives the data from the sonar sensor 5, and then the main control board 2 transmits an electrical signal to the SMA driver of the first swing arm 32 and the second swing arm 42 to heat the SMA wire 322. The SMA driver will bend due to the heat, thereby driving the first swing arm 32 and the second swing arm 42 to swing, so that the position of the towing body 1 changes, thereby avoiding running aground.

[0052] Combination Figure 6 As shown, a tilt sensor 6 is also provided at the rear end of the trailer 1. The tilt sensor 6 is connected to the main control board 2 via a data cable. The tilt sensor 6 can be used to determine whether the trailer 1 is kept in a horizontal direction.

[0053] When the ship is towing the towing body 1 by the cable, the towing body 1 will not work in the horizontal direction due to acceleration, deceleration and turning, and the towing body 1 will lose balance due to the speed of the ship itself. The inclination sensor 6 arranged on the towing body 1 will timely collect its own inclination angle and transmit the data to the main control board 2 through the line in time. The main control board 2 will compare and process the data. If the measured parameters are inconsistent with the set standard angle, the main control board 2 in the control unit will immediately send a current signal to the side swinger 3 and the middle swinger 4. At this time, the current will heat the SMA wire 322, the SMA driver will bend, drive the swing arm to swing, so that it provides a vertical upward force to help the towing body 1 return to the horizontal direction to work.

[0054] The battery is arranged in the middle of the trailer body 1, and is connected to the control unit, the side oscillator 3 and the middle oscillator 4 via a data cable, so as to ensure the normal operation of each structural component and to supply power to the SMA driver.

[0055] The side swingers 3 arranged on both sides of the towing body 1 and the middle swinger 4 arranged in the middle can be controlled individually by the main control board 2 of the control unit, and some of the swing arms can be flexibly selected to swing.

[0056] The current signal adopts a rectangular waveform with a certain duty cycle. The entire SMA driver is installed inside the first swing arm 32 and the second swing arm 42. Therefore, the bending degree of the SMA wire 322 can be adjusted by controlling the duty cycle of the current signal, thereby achieving precise control of the first swing arm 32 and the second swing arm 42.

[0057] In addition, the connection between the first swing arm 32 and the second swing arm 42 and their respective connection seats, as well as the connection between the connection seat and the trailer body 1 are sealed by watertight rubber rings to ensure good sealing of the device.

[0058] The working principle of the utility model device is as follows:

[0059] First of all, it should be noted that when the cable is fully released, the towing body 1 will be directly below the hull. At this time, the inclination sensor 6 of the towing body 1 will collect the current angle and position this angle as the standard angle. This is specially explained.

[0060] When the hull is dragged forward by the cable towing the towing body 1, the towing body 1 will not work in the horizontal direction. Due to the speed of the hull itself, the towing body 1 will be located at the upper rear position. The inclination sensor 6 set on the towing body 1 will timely collect its own inclination angle and timely transmit the data to the main control board 2 through the data cable. The main control board 2 will compare and process the data. If the parameters are inconsistent with the set standard angle, the main control board 2 in the control unit will immediately send a current signal to the side swinger 3 and the middle swinger 4. At this time, the current will heat the SMA wire 322, and the SMA driver will bend, thereby driving the first swing arm 32 and the second swing arm 42 to swing, so that it provides a vertical upward force to help the towing body 1 return to the horizontal direction to work. Whenever the hull accelerates, the towing body 1 will repeat the above process until the current angle is equal to the standard angle.

[0061] When the ship decelerates, the towing body 1 will also not work in the horizontal direction. Since the acceleration of the ship is negative, the towing body 1 will be located in the front and deviate from the horizontal position due to inertia. When the current angle is different from the standard angle, the main control board 2 in the control unit will control and heat the SMA wire 322 to provide a vertical upward force to help the towing body 1 return to the horizontal direction to work. Whenever the ship decelerates, the towing body 1 will repeat the above process until the current angle is equal to the standard angle.

[0062] When the hull turns, the hull provides the towing body 1 with centripetal acceleration through the cable. At this time, the design of the structure of the towing body 1 is not enough to keep it traveling in the horizontal direction, and it will easily roll over. At this time, the inclination sensor 6 set on the towing body 1 will timely collect its own inclination angle, and timely transmit the data to the main control board 2 through the line. The main control board 2 will compare and process the data. If the parameter is inconsistent with the set standard angle, the main control board 2 of the control unit will immediately send a current signal to the SMA driver on the side with a lower inclination angle of the towing body. At this time, the current will heat the SMA wire 322, and the SMA driver on this side will bend alone, providing a vertical upward force, so that the towing body 1 can also work stably when turning.

[0063] Combination Figures 1 to 7As shown, the utility model proposes an underwater towing body swinging device based on SMA, by utilizing the characteristic of SMA wire 322 bending under heat, setting it in the first swing arm 32 and the second swing arm 42, and transmitting current signals to the side swinger 3 and the middle swinger 4 through the main control board 2, using the current heating method to drive the first swing arm 32 and the second swing arm 42 to swing, so as to adjust the travel posture of the towing body 1. The utility model device uses steel sheets as the rebound component of the SMA driver, which can improve the rebound effect of the swing arm, ensure that the SMA wire 322 can be normally bent when the current is heated, and can achieve rapid rebound after bending. In addition, the interior of the towing body 1 is also provided with an inclination sensor 6 and a sonar sensor 5, which are respectively used to determine whether the towing body 1 is traveling in the horizontal direction and to detect and identify underwater reefs. The sensor transmits data to the main control board 2, and the main control board 2 transmits an electrical signal to the SMA driver. The SMA wire 322 is heated and bent, driving the swing arm to swing, ensuring the normal travel of the towing body 1.

[0064] It is particularly noteworthy that, since the towing body 1 operates in an underwater environment, the heat released by the SMA wire 322 can be quickly absorbed by the water in the surrounding environment, which can effectively reduce the temperature of the SMA actuator, thereby improving the stability and performance of the SMA actuator. Therefore, the actuator manufactured based on SMA in an underwater environment not only has an efficient driving function, but also has excellent heat dissipation performance, which provides a guarantee for the stable operation of the device.

[0065] Of course, the above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept of the utility model, or direct / indirect application in other related technical fields are included in the patent protection scope of the utility model and should be protected by the utility model.

Claims

1. An underwater towing body swinging device based on SMA, characterized in that: Including towing body; A control unit is provided inside the trailer, and the control unit includes a main control board; Side swingers are arranged on both sides of the towing body, and the side swingers include a first connecting seat and a first swing arm; the first connecting seat is fixedly connected to the side wall of the towing body, one end of the first swing arm is inserted into the inside of the first connecting seat, and the first swing arm is arranged horizontally; A groove is provided at the middle position of the top of the towing body, and a middle swinger is arranged in the groove, and the middle swinger includes a second connecting seat and a second swing arm; the second connecting seat is connected to the side wall of the groove, the second swing arm is connected to the second connecting seat, and the second swing arm is arranged vertically; The first swing arm and the second swing arm have the same internal structure, and both use an SMA driver and a steel sheet for realizing the recovery deformation of the SMA driver; The main control board is connected to the SMA driver via a data cable.

2. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: The SMA driver includes a PCB board and an SMA wire; Wherein, a PCB board is symmetrically arranged at both ends of the SMA actuator, and a plurality of through holes are opened at corresponding positions of the two PCB boards, and the spacing between adjacent through holes is equal; The SMA wires are passed through the through holes at corresponding positions on the two PCB boards and tightened, and the SMA wires are parallel to each other with gaps left; The main control board is connected to the PCB board via a data cable; The SMA actuator was encapsulated with PDMS.

3. The underwater towing body swinging device based on SMA according to claim 2 is characterized in that: The steel sheet is bonded to the back surface of the SMA actuator by waterproof adhesive, and is encapsulated together with the SMA actuator as a whole by PDMS.

4. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: A sonar sensor is arranged on the main control board.

5. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: An inclination sensor is also arranged inside the trailer, and the inclination sensor is connected to the main control board via a data cable.

6. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: The trailer is also provided with a battery, and the battery is connected to the control unit, the side swinger and the middle swinger through a data cable.

7. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: Two groups of first swing arms are arranged on the first connecting seat.

8. The underwater towing body swinging device based on SMA according to claim 1 is characterized in that: The first connecting seat is fixed to the towing body by bolts.

9. The underwater towing body swinging device based on SMA according to claim 1, characterized in that: The thickness of the steel sheet is 0.6 mm.

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