Patent ID: 12187395

DETAILED DESCRIPTION OF EMBODIMENTS

The present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are intended to facilitate the understanding of the present invention and do not limit the present invention in any way.

A flexible capturing system for an underwater moving carrier includes a front-end flexible guide apparatus, a tail flexible hand clamping and fastening apparatus, a bottom lifting or lowering retracting apparatus, and a system towing apparatus.

The front-end flexible guide apparatus includes flexible arms1wound with reinforcing fiber that form a circumferential array. A quantity of flexible arms of the flexible guide apparatus is preferably 6 to 8. The flexible arms1are installed on a rigid installing base plate18, and a base is connected to a vertical flexible arm32through a bending rod4.

As shown in (a) ofFIG.1, a flexible arm body13made of a silicone rubber soft body is used to recover the underwater moving carrier. Outside of the flexible arm body13is wrapped by the reinforcing fiber12to constrain radial expansion, and an electronic compass15is installed at an end to perform attitude feedback control. A fastening joint11is installed at a root of the flexible arm body13for installing the flexible arm1on the installing base plate18.

As shown in (b) ofFIG.1, there are two symmetrical liquid-filled flow channels16inside the flexible arm, and environmental liquid is pumped through a pump for pressurization. A cable routing hole17is provided in the middle of the flexible arm for placing a watertight cable corresponding to the electronic compass.

A plurality of flexible arms are evenly arranged on the installing base plate18, so that a horn-shaped flexible guiding apparatus can be formed to restrain and guide the underwater moving carrier.

A blocking net is preferably installed on an inner side of the flexible arm, so that when the underwater moving carrier collides with the flexible guiding apparatus, a plurality of arms are stressed simultaneously, reducing an ultimate collision force to each arm.

The tail flexible hand clamping and fastening apparatus includes flexible claws2. The flexible claws2are in a semi-bellow shape. A quantity of semi-bellow flexible arms21included in each group of flexible claws2is preferably four.

As shown inFIG.2, one group of flexible claws2includes four semi-bellows flexible arms21, and each semi-bellows flexible arm includes three small sections connected in series. After being filled with liquid, a root section211is bent toward the outside, and a middle section212and an end section213are bent toward the inside, so that carriers of different sizes can be winded at different unfolding angles, and space occupied during winding and storage can be kept small. Attitude sensors22are installed at joints and ends of the root section211, the middle section212, and the end section213.

FIG.3is a schematic diagram of a driving principle for one section of the flexible claw. One side of a structure is bellows-shaped, and a plane of the other side is pasted with a strain limiting layer214with a larger elastic modulus, so that the flexible arm bends toward an opposite side of a bellows after fluid is introduced.

According to geometric sizes of different underwater moving carriers, the flexible guide apparatus and the flexible claw are clamped and winded in different manners. A preferred manner is as follows:

When the underwater moving carrier has a large size, the front-end flexible guide apparatus forms a shape that an inner diameter of a circumference distributed just wraps the carrier, and the flexible claw wraps around a middle part and rear part of the carrier, to prevent a tail of the carrier from tilting up under a positive buoyancy and leading to capturing failure. When the underwater moving carrier has a small size, the front-end flexible guide apparatus needs to bend to an inner side of a circumference distributed to compress the carrier, and the tail flexible claw remains bent and wrapped and is not in contact with the carrier.

FIG.4andFIG.5show a manner in which the front-end flexible guide apparatus and the rear-end flexible claw cooperate to grasp different underwater moving carriers. Optionally, when a diameter of an underwater moving carrier A is 324 mm, the flexible guide apparatus and the flexible claws2need to act cooperatively. To be specific, after the flexible guide apparatus limits a carrier direction, the flexible guide apparatus is quickly closed, and then the flexible claws2are triggered to grasp and wind and fasten the underwater moving carrier. When a diameter of the underwater moving carrier is 180 mm, a size of flexible arms1is enough to cover most of a length of the underwater moving carrier. Therefore, the flexible claws2remain in a winding state and wait for the carrier to drop into a cabin.

Driving manners for the front-end flexible guide apparatus and the rear-end flexible claws are divided into two stages: liquid pre-filling and rapid actuation. In a previous stage, liquid is slowly pumped into an internal cavity of the flexible arm through a small-flow pump until a liquid volume is the same as a volume of the internal cavity, without squeezing an internal flow channel. When the underwater moving carrier enters capturing space of the flexible arm, a characteristic of a liquid volume modulus is used to perform small-flow liquid supplementing, which rapidly increases a cavity pressure of the flexible arm and generates an equivalent moment on the flexible arm to make the flexible arm quickly bend, implementing rapid actuation of the flexible arm with a small flow.

A two-layer adaptive robust control method is used for the flexible arms. When the underwater moving carrier approaches the flexible capturing system, an underwater sonar/visual hybrid sensing system sends an action trigger signal, calculates a desired posture of the flexible arms, and inputs the desired posture into a control system. The control system first uses a back-stepping controller to design a control rate that satisfies Lyapunov stability, and forms an intermediate target control amount, that is, a desired speed of the flexible arm, by using superposition of parameter adaptive regression of a flexible arm model (a posture and velocity model), model error compensation, nonlinear robust feedback, and linear stable feedback. Furthermore, based on a current speed of the flexible arm, a control pressure of the underwater flexible arm is obtained through four calculation steps including parameter adaptive regression of a flexible arm model (a model of a relation between a speed and a velocity), model error compensation, nonlinear robust feedback, and linear stable feedback, thereby achieving precise control of the flexible arm posture.

The bottom lifting or lowering retracting apparatus includes a winch31, a combination of vertical flexible arms32, and a towing body33. A net buoyancy of the vertical flexible arm32in water is preferably designed to be a positive value. After the winch31rotates forward, rigidity of the flexible arm can be increased rapidly after being detached from the winch. When the winch31rotates reversely, liquid inside the flexible arm is discharged to relieve pressure. The rigidity of the flexible arm is increased in the following method:

A part that is of the flexible arm and that is detached from the winch quickly pumps seawater into the flexible arm through a hydraulic pump. An internal flow channel of the flexible arm is squeezed and expanded by the liquid, and outside of the flexible arm is wrapped and constrained by a fiber rope, increasing material rigidity of the flexible arm. After the flexible arm is released from the winch, the flexible arm rises upward under the action of a positive buoyancy to form a vertical flexible arm, while a part of the flexible arm filled with liquid remains on the winch, so that rigidity of a rigid-flexible junction at a root of the vertical flexible arm is enough to support a carrier recovery action on an upper part the flexible arm.

When the flexible arm clamps and wraps the carrier, the winch reverses and rolls up the flexible arm, to drive the carrier down into the towing body, reducing the impact of water resistance on stability of carrier clamping. By far, recovery of the underwater moving carrier is completed.

As shown inFIG.6, a recovery system for an underwater moving carrier is connected to a water surface mother ship B through a towing cable C. Several winches31are installed inside the towing body33to wind and release the vertical flexible arm32. The vertical flexible arm32is connected to the flexible arm1and the flexible claw2to form a complete flexible recovery structure. Through the cooperation of the winch and the towing body, the carrier recovery can be completed, as follows:

When the underwater moving carrier approaches the flexible capturing system, an underwater sonar/visual hybrid sensing system sends an action trigger signal, calculates a desired posture of the flexible arms, and inputs the desired posture into a control system. The winch rotates forward and the flexible arm is detached from the winch. A part that is of the flexible arm and that is detached from the winch quickly pumps seawater into the flexible arm through a hydraulic pump. An internal flow chamber of the flexible arm is squeezed and expanded by the liquid, and outside of the flexible arm is wrapped and constrained by a fiber rope, increasing material stiffness of the flexible arm. After the flexible arm is released from the winch, the flexible arm rises upward under the action of a positive buoyancy to form a vertical flexible arm, while a part of the flexible arm filled with liquid remains on the winch, so that stiffness of a rigid-flexible junction at a root of the vertical flexible arm is enough to support a carrier recovery action on an upper part the flexible arm. When the flexible arm clamps and wraps the carrier, the winch reverses and rolls up the flexible arm, to drive the carrier down into the towing body, reducing the impact of water resistance on stability of carrier clamping. By far, the recovery of the underwater moving carrier is completed, and a recovery status is shown inFIG.7.

As shown inFIG.8, a two-layer adaptive robust control method is used for the flexible arm. The control system first uses a back-stepping controlling method to design a control rate that satisfies Lyapunov stability, and forms an intermediate target control amount, that is, a desired speed of the flexible arm, by using superposition of parameter adaptive regression a flexible arm model (a posture and velocity model), model error compensation, nonlinear robust feedback, and linear stable feedback. Furthermore, based on a current speed of the flexible arm, a control pressure of the underwater flexible arm is obtained through four calculation steps including parameter adaptive regression of a flexible arm model (a model of a relation between a speed and a velocity), model error compensation, nonlinear robust feedback, and linear stable feedback, thereby achieving precise control of the flexible arm posture.

The above embodiments describe in detail the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modification, supplement, equivalent substitution, or the like made within a principle scope of the present invention shall be included in the protection scope of the present invention.