Patent Publication Number: US-11377183-B2

Title: Autonomous underwater vehicle (AUV) launch and recovery device driven by elastic linkage mechanism for extra-large unmanned underwater vehicle (XLUUV)

Description:
FIELD 
     The present disclosure relates to the field of underwater vehicles, in particular to an autonomous underwater vehicle (AUV) launch and recovery device driven by an elastic linkage mechanism for an extra-large unmanned underwater vehicle (XLUUV). 
     BACKGROUND 
     With development of marine resources and change in strategic situation of coastal defense, an unmanned long-time underwater operation became a hotspot, and various countries stepped up development of large unmanned underwater systems and research on technologies related to the large unmanned underwater systems. 
     The large unmanned underwater systems are large unmanned underwater integrated operation platforms with sensors, weapons and other loads, and the large unmanned underwater integrated operation platforms can be controlled remotely, and semi-autonomously or autonomously to operate. Compared with small and medium unmanned systems, the large unmanned underwater systems have the advantages of being longer in range and working time, lower in dependence on a manned platform, smaller in influence on marine environment, higher in reliability, autonomous operational capability and cost effectiveness, and the like. The characteristic of the large-scale unmanned underwater system is that it adopts open structure and modular design, so that the large-scale unmanned underwater system can reconstruct the payload and tasks, replace a manned platform to carry out most ISR tasks and undertake anti-submarine and attack operations. At present, the United States Navy continuously accelerates a research, development and deployment process of large unmanned underwater systems, and a proposed “extra-large unmanned underwater vehicle (XLUUV)” is a large unmanned underwater vehicle which is provided with modular load cabins and executes high-risk tasks being long in navigation time and needing to avoid personal casualties. Based on this, an AUV launch and recovery device is designed by using an XLUUV as an underwater recovery platform, so that the XLUUV can carry a small AUV. The XLUUV launches AUV into complex water to carry out tasks and recovers the AUV underwater to supplement energy for reuse. This working mode not only can improve the combat effectiveness, but also greatly improve the efficiency cost ratio. 
     The AUV launch and recovery technology for the extra-large unmanned underwater vehicle is still in an initial stage. There are few documents and data with this regard. For example, CN107697247A provides an AUV underwater launch and recovery device, but a flared shaped structure of the device cannot form an airtight cage-shaped structure due to mechanical structure limitation, and an additional space is required for installation of a driving device. CN108569385A provides an AUV underwater recovery locking mechanism which has the main defect that a flared shaped structure at a front end of a recovery mechanism cannot be closed. The present disclosure adopts “Echo Voyager” extra-large unmanned underwater vehicle of the Boeing Company as a template, and provides an AUV launch and recovery device using the XLUUV to achieve underwater launch and recovery of AUVs; and the device can play a significant role not only in the military field but also in marine science and other fields, and finish various underwater operation tasks more reliably and efficiently. 
     SUMMARY 
     Problems to be solved by the present disclosure: to avoid defects existing in the prior art, the present disclosure provides an autonomous underwater vehicle (AUV) launch and recovery device driven by an elastic linkage mechanism for an extra-large unmanned underwater vehicle (XLUUV); the AUV launch and recovery device launches and recovers small and medium rotary AUVs under navigation with cooperation between elastic rubber plates and inelastic hauling ropes, and this device has a simple and compact structure and reliable actions; and this AUV launch and recovery device is a feasible device for launching and recovering the small and medium rotary AUVs. 
     Embodiments of the present disclosure are as follows: the AUV launch and recovery device driven by the elastic linkage device for the XLUUV includes a tail end fixing box body, a tail end limit displacement block, a tail end driving case, a hydraulic device, a push plate, a tubular device box and an external sleeve. The AUV launch and recovery device is a frame type tubular structure, one end of the AUV launch and recovery device is a recovery end, the other end is closed, and this end is coaxially fixed with the tail end fixing box body through the tail end limit displacement block; the front end face of the tail end fixing box body is processed with a groove, and the groove position is in the radial direction of the tail fixed box body. The push plate is parallel to the central axis of the AUV launch and recovery device, and one end of the push plate is installed in cooperation with the groove of the tail end fixing box body. The hydraulic device is installed in the tail end driving case, and the hydraulic rod of the hydraulic device can extend out of the tail end driving case. The push plate is fixed to the hydraulic rod, and the control system controls the movement of the hydraulic rod to make the push plate move radially in the groove. 
     The external sleeve coaxially sleeves the periphery of the AUV launch and recovery device, and is used for fixing the whole AUV launch and recovery device to the XLUUV; and the tail end driving case is positioned by an L-shaped driving case positioning tube fixed to a peripheral surface of the external sleeve. 
     The tubular device box includes a tail end sleeve positioning plate, an impact cushion, metal guide rods, annular AUV positioning plates, elastic AUV positioning rings, front end sleeve positioning plates, elastic rubber plates, inelastic hauling ropes, front end elastic rings and an inelastic linkage rope, where the tail end sleeve positioning plate, the annular AUV positioning plates and the front end sleeve positioning plates are sequentially and coaxially arranged, and the metal guide rods are uniformly distributed circumferentially, and penetrate through holes in edges of the annular AUV positioning plates; one end of each metal guide rod is fixed to an inner side surface of the tail end sleeve positioning plate, the other end is fixed to inner side ring surfaces of the front end sleeve positioning plates, and all metal guide rods are arranged in a circle; the tail end sleeve positioning plate adopts a circular plate structure, and the impact cushion is coaxially fixed to an inner side surface of the tail end sleeve positioning plate; the tail end sleeve positioning plate is coaxially fixed to the front end elastic ring; all annular AUV positioning plates and front sleeve positioning plates are annular structure, the annular structure is processed with two types of holes for installing the metal guide rods and the inelastic hauling ropes, and the elastic AUV positioning rings are coaxially installed on ring inner hole walls of the annular AUV positioning plates and the front end sleeve positioning plates; the elastic AUV positioning rings are made of elastic materials, and inner hole diameters of the elastic AUV positioning rings are smaller than an outer diameter of an AUV to be recovered; the AUV to be recovered is located through friction and elastic force generated by elastic deformation; one elastic rubber plate is taken as an example, one end of the elastic rubber plate is installed with a threaded cylinder, which passes through the annular hole of the front sleeve positioning plate and is fixed with an metal guide rod; all elastic rubber plates form a circular arrangement; and one front end elastic ring is taken as an example, the original structure is an elastic rope. One end passes through all holes in the same circular plane of all elastic rubber plates to form a closed elastic ring. All the front end elastic rings and elastic rubber plates form an elastic structure, which can form a cage structure or a bell mouth structure. The number of inelastic hauling ropes and elastic rubber plates is the same. Take one inelastic hauling rope as an example, the inelastic hauling rope is parallel to the axis of the tail end limit displacement block in the tubular device box, the front end of the inelastic hauling rope is fixed to the front end of the elastic rubber plates and the tail end passes through the hole of the annular AUV positioning plate in turn and finally fixed on the tail end fixing box body. After the installation process, all the inelastic hauling ropes form a cylindrical tubular structure, and all the inelastic hauling ropes are in tension state. 
     The inelastic linkage rope is installed between the tail end fixing box and the tail end sleeve positioning plate, one end of the inelastic linkage rope is fixed on the tail end driving case, the other end passes through the hole on the surface of the push plate, bypasses all the inelastic hauling ropes arranged in a circle, passes through another hole on the push plate and is fixed on the tail end driving case to form a closed ring, and all the inelastic hauling ropes are closed inside the ring. The hydraulic rod controls the push plate to move upward or downward, and makes the annular center formed by the inelastic linkage rope shrink or expand, so that the elastic rope moves axially by relative motion, further pulls the front ends of the elastic rubber plates to achieve the open or close state of the front end elastic structure. 
     Further, the tail end fixing box body adopts a cylindrical structure, and a threaded hole is formed in a center of the fixing box body. The tail end limit displacement block is a stepped cylindrical structure, which is fixed with the tail fixed box body through thread installation. 
     Further, the tail end sleeve positioning plate and a plurality of the annular AUV positioning plates and the front end sleeve positioning plates are arranged equidistantly. 
     Further, The guide rod positioning sleeve are installed on the guide rod, and both sides of each AUV positioning plate need to be installed to prevent the AUV positioning plate from moving. 
     Further, the inelastic hauling ropes are parallel to the axis of the tail top block in the tubular device box. 
     Further, one elastic rubber plate is taken as an example, one end of the elastic rubber plate is installed with a threaded cylinder, which passes through the hole of the front sleeve positioning plate and is fixed with the metal guide rod. The number of elastic rubber plates is the same as that of the metal guide rods. All elastic rubber plates form an approximate cylindrical structure after installation. 
     Further, one end of an external sleeve is coaxially fixed to an inner ring surface of the front end sleeve positioning plates, and the other end of the external sleeve is coaxially fixed to an inner side surface of the tail end sleeve positioning plate. 
     Further, the device further includes two pairs of sleeve brackets arranged in parallel, and the sleeve brackets are fixed to a bottom of the external sleeve, fix the whole AUV launch and recovery device to the XLUUV or install the device in the XLUUV. 
     BENEFICIAL EFFECTS 
     The present disclosure has the beneficial effects: the present disclosure integrates all required devices for AUV launch and recovery into a small tubular device, especially including a driving device, and the structure is compact; AUVs can be recovered into an XLUUV, or can be hung at an exterior of the XLUUV as an external load; during launch and recovery of the AUVs, actions of opening and closing a guide cover port at a recovery end are finished through relative motion with cooperation among a hydraulic device, elastic ropes and inelastic ropes, and therefore, an overall length of the AUV launch and recovery device is shortened; and the device has a simple structure and low manufacturing costs. Furthermore, an installation space is reduced, and possibility that the XLUUV carries more small AUVs is improved, improving the cost effectiveness. 
     Under a condition that the AUVs go out to execute tasks or are locked, the front end flared shaped guide cover of the AUV launch and recovery device is almost closed completely, so that an enclosed space is formed in the tubular device box; and a risk that an inner part of the device is blocked by large foreign matter and consequently recovery is affected, is reduced. 
     The AUV launch and recovery device not only can be recovered into the XLUUV, but also can be hung at an outer part of an underwater platform as an external load. As the guide cover can be opened and closed as required, it can slow down the hydrodynamic decline of the original large-scale underwater platform. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a three-dimensional structure diagram of an AUV launch and recovery device for an XLUUV; 
         FIG. 2  shows a partial sectioned view of the AUV launch and recovery device; 
         FIG. 2 a    shows a structure diagram of an external sleeve and a connecting device of the AUV launch and recovery device; 
         FIG. 3  shows a partial view  1  of a driving device when the AUV launch and recovery device is under a condition that AUVs are locked; 
         FIG. 3 a    shows a partial view  2  of the driving device when the AUV launch and recovery device is under a condition that the AUVs are locked; 
         FIG. 4  shows a partial sectioned view of a driving device when the AUV launch and recovery device is in an open state; 
         FIG. 4 a    shows a partial enlarged view of the driving device when the AUV launch and recovery device is in an open state; 
         FIG. 5  shows a schematic diagram of the AUV launch and recovery device waiting for recovery; 
         FIG. 6  shows a schematic diagram of the AUV launch and recovery device performing launch/recovery; 
         FIG. 7  shows a schematic diagram of the AUV launch and recovery device in a recovery completion state; 
         FIG. 8  shows a partial view of a guide cover of the AUV launch and recovery device. 
     
    
    
     REFERENCE NUMERALS 
       1 . XLUUV;  2 . revolving AUV launch and recovery device;  3 . tail end fixing box body;  4 . tail end limit displacement block;  5 . tail end sleeve positioning plate;  6 . impact cushion;  7 . metal guide rod;  8 . annular AUV positioning plate;  9 . guide rod positioning sleeve;  10 . elastic AUV positioning ring;  11 . external sleeve;  12 . front end sleeve positioning plate;  13 . elastic rubber plate;  14 . front end elastic ring (refers to a flexible ring structure formed by the combination of a closeable elastic rope and an elastic rubber plate);  15 . inelastic hauling rope;  16 . sleeve bracket;  17 . inelastic linkage rope;  18 . push plate;  19 . hydraulic rod;  20 . tail end driving case;  21 . driving case positioning tube;  22 . AUV;  23 . groove;  24 . central axis;  25 . thread;  26 . ring inner hole wall;  27 . threaded cylinder;  28 . annular hole;  29 . hole; and  30 . threaded hole. 
     DETAILED DESCRIPTION 
     Examples described below with reference to accompanying drawings are illustrative, which are merely intended to explain the present disclosure, rather than to limit the present disclosure. 
     In the description of the present disclosure, it should be noted that terms “central”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, “anticlockwise” and the like, are used to indicate orientations or position relationships shown in accompanying drawings. It should be noted that these terms are merely intended to facilitate a simple description of the present disclosure, rather than to indicate or imply that the mentioned apparatus or elements must have the specific orientation or be constructed and operated in the specific orientation. Therefore, these terms may not be construed as a limitation to the present disclosure. 
     In this embodiment, for a whole launch and recovery device and any parts in the device, define one end close to a recovery end axially, as “a front end”, and the other end as “a tail end” correspondingly. 
     Refer to  FIG. 1 , the whole recovery device is placed in an extra-large unmanned underwater vehicle. The device is located above the underwater vehicle during launch and recovery. 
     Refer to  FIG. 2 - FIG. 4 a   , the AUV launch and recovery device driven by an elastic linkage device for an XLUUV includes a tail end fixing box body  3 , a tail end limit displacement block  4 , a tail end driving case  20 , a hydraulic device  19 , a push plate  18 , a tubular device box and an external sleeve  11 . The AUV launch and recovery device is a frame type tubular structure, the front end of the AUV launch and recovery device is a recovery end, the tail end is closed, and this end is coaxially fixed with the tail fixing box body  3  through the tail end limit displacement block  4 ; the front end face of the tail end fixing box body  3  is processed with a groove  23 , and the groove position is processed in the radial direction of the tail end fixing box body  3 . The push plate  18  is parallel to the central axis  24  of the AUV launch and recovery device, and one end of the push plate  18  is installed in cooperation with the groove  23  of the tail end fixing box body  3 . The hydraulic device  19  is installed in the tail end driving case  20 , and the hydraulic rod  19  of the hydraulic device can extend out of the tail end driving case  20 . The push plate  18  is fixed to the hydraulic rod  19 , and the control system controls the movement of the hydraulic rod  19  to make the push plate move radially in the groove  23 . 
     The external sleeve  11  coaxially sleeves the periphery of the AUV launch and recovery device, and is used for fixing the whole AUV launch and recovery device to the XLUUV; and the tail end driving case  20  is positioned by an L-shaped driving case positioning tube  21  fixed to a peripheral surface of the external sleeve  11 . 
     The tubular device box includes a tail end sleeve positioning plate  5 , an impact cushion  6 , metal guide rods  7 , annular AUV positioning plates  8 , elastic AUV positioning rings  10 , front end sleeve positioning plates  12 , elastic rubber plates  13 , inelastic hauling ropes  15 , front end elastic rings  14  and an inelastic linkage rope  17 , where the tail end sleeve positioning plate  5 , the annular AUV positioning plates  8  and the front end sleeve positioning plates  12  are sequentially and coaxially arranged, and the metal guide rods  7  are uniformly distributed circumferentially, and penetrate through holes in edges of the annular AUV positioning plates  8 ; one end of each metal guide rod  7  is fixed to an inner side surface of the tail end sleeve positioning plate  5 , the other end is fixed to inner side ring surfaces of the front end sleeve positioning plates  12 , and all metal guide rods  7  are arranged in a circle; the tail end sleeve positioning plate  5  adopts a circular plate structure, and the impact cushion  6  is coaxially fixed to an inner side surface of the tail end sleeve positioning plate  5 ; the tail end sleeve positioning plate  5  is coaxially fixed to the front end elastic ring  14 ; all annular AUV positioning plates  8  and the front end sleeve positioning plates  12  are an annular structure, the annular structure is processed with two types of holes for installing the metal guide rods  7  and the inelastic hauling ropes  15 , and the elastic AUV positioning rings  10  are coaxially installed on ring inner hole walls  26  of the annular AUV positioning plates and the front end sleeve positioning plates; the elastic AUV positioning rings  10  are made of elastic materials, and inner hole diameters of the elastic AUV positioning rings  10  are smaller than an outer diameter of an AUV  22  to be recovered; the AUV  22  to be recovered is located through friction and elastic force generated by elastic deformation; and one elastic rubber plate  13  is taken as an example, tail end of the elastic rubber plate  13  is installed with a threaded cylinder  27 , which passes through the annular hole  28  of the front end sleeve positioning plate  12  and is fixed with the metal guide rod  7 . All elastic rubber plates  13  form a circular arrangement; one front end elastic ring  14  is taken as an example, the original structure is an elastic rope, one end passes through all holes in the same circular plane of all elastic rubber plates  13  to form a closed elastic ring, the elastic rubber plate  13  and all front end elastic rings  14  form an elastic structure, which can form a cage structure or a bell mouth structure, and the number of inelastic hauling ropes  15  and elastic rubber plates  13  is the same. One inelastic hauling rope  15  is taken as an example, the inelastic hauling rope  15  is parallel to the axis of the tail top block  4  in the tubular device box, the front ends of the inelastic hauling ropes  15  are fixed to the front end of the elastic rubber plates  13  and the tail ends pass through the hole of the annular positioning plate in turn and finally are fixed on the tail end fixing box body  3 . After the installation process, all the inelastic hauling ropes  15  form a cylindrical tubular structure, and all the inelastic hauling ropes  15  are in tension state. 
     The inelastic linkage rope  17  is installed between the tail end fixing box  3  and the tail end sleeve positioning plate  5 . One end of the inelastic linkage rope  17  is fixed on the tail end driving case  20 , and the other end passes through the hole  29  on the surface of the push plate  18 , bypasses all the inelastic hauling ropes  15  arranged in a circle, passes through another hole  29  on the push plate  18  and is fixed on the tail end driving case  20  to form a closed ring, and all the inelastic hauling ropes  15  are closed inside the ring. When the hydraulic rod  19  controls the push plate  18  to move upward, the annular center formed by the inelastic linkage rope  17  shrinks, resulting in the axial movement of the elastic hauling rope  15  to the tail end, thus tightening the front end of the elastic rubber plates  13 , and forming a horn mouth structure at the front end. When the pushing plate  18  moves downward, the ring formed by the inelastic linkage rope  17  expands, the front end of the AUV launch and recovery device forms a cage structure under the action of the elastic rubber plate  13  and the front end elastic ring  14 . 
     Refer to  FIG. 2  and  FIG. 3 a   , the tail end fixing box body  3  is connected with the tail end limit displacement block  4  by threads  25 , and the tail end limit displacement block  4  is connected with the tail end sleeve positioning plate  5  by screws and welding. The impact cushion  6  is fixed to a front end surface of the tail end sleeve positioning plate  5  by screws. 
     Refer to  FIG. 2 , twelve metal guide rods  7  are arranged in a ring with the same spacing angle, and the tail end is connected to the tail end sleeve positioning plate  5  through thread and welding; each AUV positioning plate  8  needs to be axially positioned on the guide rods  7  by using two guide rod positioning sleeves  9 , and inner ring wall diameters of the guide rod positioning sleeves  9  are in interference fit with outer wall diameters of the guide rods  7 ; and the elastic AUV positioning rings  10  are fixed to inner ring walls of the annular AUV positioning plates  8  by pins. All annular AUV positioning plates  8 , guide rod positioning sleeves  9 , AUV positioning rings  10  and the front end sleeve positioning plates  12  are installed in the same way we just give. 
     Refer to  FIG. 2 a   , after the four annular AUV positioning plates are installed, a tail end of the external sleeve  11  is connected to the tail end sleeve positioning plate  5  by screws, and then, the front end sleeve positioning plates  12  and the matched AUV positioning rings  10  are installed; and the front end sleeve positioning plates  12  are connected to the front end of the external sleeve  11  by screws, so that sleeve positioning is finished. 
     A tubular device box body recovery section is formed by the tail end sleeve positioning plate  5 , the guide rods  7 , the four annular AUV positioning plates  8 , the external sleeve  11 , the front end sleeve positioning plates  12 , the matched guide rod positioning sleeves  9 , and the AUV positioning rings  10 ; and the tubular device box body recovery section is an integral rigid body. 
     Two pairs of brackets  16  are fixedly connected to the surface of the external sleeve  11 , which can be used to connect other bases or hydraulic devices, so that the AUV launch and recovery device not only can be placed inside the large underwater platform, but also be suspended outside as an external load. 
     A tail end of each elastic rubber plate  13  is connected with a front end of each metal guide rod  7  by thread, and twelve elastic rubber plates  13  are combined into an elastic integral structure by using nine front end elastic rings  14 ; the most front end of each elastic rubber plate  13  is connected with a front end of one inelastic hauling rope  15  by screws, and a tail end of the inelastic hauling rope  15  is fixedly connected with the tail end fixing box body  3 ; and after completion of installation, it should be ensured that the inelastic hauling ropes  15  are in a tensioning state when the launch and recovery device is in the closed state. 
     One end of the inelastic linkage rope  17  is fixed on the tail end driving case  20 , the other end passes through the hole  29  on the surface of the push plate  18 , bypasses all the inelastic hauling ropes  15  arranged in a circle, passes through another hole  29  on the push plate  18  and is fixed on the tail end driving case  20  to form a closed ring, and all the inelastic hauling ropes  15  are closed inside. The pushing plate  18  pushes upward to shrink the annular center formed by the inelastic linkage rope  17 , so that the elastic hauling rope  15  moves axially. 
     The push plate  18  is welded and fixed to the hydraulic rod  19 , one side of the tail end of the push plate  18  is clamped in the groove  23  of the tail end fixing box body  3 , and the hydraulic device  19  is placed in the tail end driving case  20 , fixed by screws, and sealed with a sealing ring. In order to ensure the positioning of the tail end driving case  20 , the tail end driving case  20  is fixed to the driving case positioning tube  21  by welding and threaded connection, and the driving case positioning tube  21  is fixed to the external sleeve  11  by welding and threaded connection. 
     After all installation procedures of the AUV launch and recovery unit are completed and the front-end guide cover is set to be closed, in this state, it must be ensured that all the inelastic hauling ropes  15  are in tension and straight state, and that the inelastic linkage ropes  17  and the pushing plate  18  exert a small amount of pressure on the inelastic hauling ropes  15 . 
     When the XLUUV  1  launches the AUV  22 , the front end forms a flared shaped structure, and the AUV  22  leaves the device box by AUV&#39;s own power, and then forms a cage structure in the front end under the elastic action of the front end elastic ring  14  and the elastic rubber plate  13 . 
     When the XLUUV  1  recovers the AUV  22 , the front end forms a flared shaped structure, and the AUV  22  runs to be close to the XLUUV  1 . Equipment of a sonar, a signal transponder and the like which are installed in the box automatically navigates the AUV  22  to be aligned to the range of the flared shaped guide cover and lead the AUV  22  to enter the device box  2  so that the AUV  22  is fixed, then a cage structure is formed in the front end under the elastic action of the front end elastic rings  14  and the elastic rubber plate  13 , and the AUV recovery task is finished. 
     Such detachable launch and recovery device has a simple and compact structure; due to self-propulsion of the AUV, the relevant AUV launch system does not need to be installed in the device box; if the AUV is permitted to be in a wet storage state, a maintenance system is not needed, and the external sleeve can be removed as appropriate; and if the AUV is required to be in a dry storage state, a maintenance device can be additionally arranged in the external sleeve. 
     In  FIG. 3  and  FIG. 6 , when entering the AUV launch state, a control system sends a signal for controlling the hydraulic device  19  to start, so that the push plate  18  moves upwards along the groove  23  in the tail end fixing box body  3 ; therefore, the ring formed by the inelastic linkage rope  17  shrinks toward the center, enabling the inelastic linkage rope  17  to give the inelastic hauling ropes  15  force in the collapsed state, so that the inelastic hauling ropes  15  move toward the tail axially; if the tail end fixing box body  3  is regarded as a coordinate origin, a Cartesian right-handed coordinate system is established, namely that the inelastic hauling ropes  15  move toward the tail end, and the elastic rubber plates  13  are bent outwards through relative motion; at the moment, a sensor is used for measurement to determine that the rubber plates  13  are bent outwards indeed; if the sensor detects and determines that the rubber plates  13  are not bent outwards, the control system controls the hydraulic driving to return to the closed state; and reopening is performed till the rubber plates  13  are bent outwards and reach a preset position, so that a recovery end is in the stable open state circumferentially. At the moment, the front end forms a flared shaped structure, and the AUV  22  is launched outside the device box  2  by own power. 
     In  FIG. 4  and  FIG. 4 a   , after the sensor determines that the launch is completed, the control system controls the hydraulic system to reset, so that the push plate  18  moves downward to the original position, the elastic rubber plate  13  gradually recovers to bend inward, the inelastic hauling ropes  15  and the inelastic linkage rope  17  are reset, and the guide cover is closed; in the closed state, the inelastic hauling ropes  15  are in the tension state, and the elastic rubber plate  13  is always bent inward depending on the tension of the front end elastic ring  14 , so that the AUV launch and recovery device is closed, and it is not easy to open under the action of external force. 
     In  FIG. 5 , when the XLUUV  1  is ready to recover AUV  22 , the hydraulic rod of the hydraulic device  20  moves upward to form a flared shaped structure at the front end, waiting for the AUV  22  to enter the tubular device box  2 . 
     In  FIG. 6 , after regulation of an approach attitude of the AUV  22 , the head of AUV enters the flared shaped guide cover, and can be pushed into the tubular device box body recovery section along the flared shaped guide cover under AUV&#39;s own power, so that an axis of the AUV  22  is approximately aligned with that of the tubular device box body recovery section. At the moment, the sensor is used for detection; and once a distance between the head of the AUV  22  and the tail end sleeve positioning plate  5  reaches ½ of length of the tubular device box body recovery section, the hydraulic device  20  is controlled to start to reset, the push plate  18  moves downwards, and the guide cover is retracted gradually. 
     In  FIG. 7 , the AUV  22  passes through the four positioning plates  8  based on own power, and since the inner diameter of the AUV positioning rings  10  is slightly smaller than the diameter of the rotating part in the middle of the AUV  22 , the AUV positioning is completed under the annular AUV positioning plates  8  and the elastic action of the elastic AUV positioning rings  10 . 
     When AUV  22  has passed through all positioning plates but has not collided with impact cushion  6 , it is necessary to ensure that the hydraulic device  19  has been reset and the front end forms a cage structure. 
     Then the AUV collides slightly with the impact cushion  6 . After the AUV head navigation system determines that the AUV position is stable, the AUV  22  stops the output power; the elastic rubber plates  13  and the front end elastic rings  14  form a cage structure under the elastic recovery force; and the recovery of the AUV has been completed. 
     Ropes, namely the inelastic hauling ropes  15 , mentioned in the patent jointly consist of inelastic hauling ropes and rubber sleeves outside the ropes, and the ropes and the matched rubber sleeves are both made of materials having properties of low elasticity and high resistance to wear and corrosion; and the corrosion resistance of the ropes is improved. Short for the inelastic hauling ropes, and a structure and a material of the inelastic linkage rope  17  are the same as those of the inelastic hauling ropes  15 . 
     The original structure of one front-end elastic ring  14  is a composite elastic rope, it is jointly consist of ropes and rubber sleeves outside the ropes, and the ropes and the matched rubber sleeves are both made of materials having properties of medium elasticity and high resistance to wear and corrosion; and the corrosion resistance of the ropes is improved. The two ends of the rope can be connected by thread connection method to form a closed ring. 
     In  FIG. 8 , twelve elastic rubber plates  13  are combined into an elastic integral structure by using nine front end elastic rings  14 , and the diameter of the elastic ring  14  installed at the front end of the elastic rubber plate  13  is larger than that of the elastic rings  14  installed at other positions of the elastic rubber plate  13 . 
     Although examples of the present disclosure have been illustrated and described, it can be understood that the above examples are exemplary and cannot be construed as a limitation to the present disclosure.