CN-121697820-B - Buoyancy adjusting method based on multi-cascade nested cylinders

CN121697820BCN 121697820 BCN121697820 BCN 121697820BCN-121697820-B

Abstract

The invention discloses a buoyancy adjusting method based on multiple cascade nested cylinders, which belongs to the technical field of surveying and comprises the steps of (1) generating a lookup table by using depth adjusting ranges corresponding to the cascade nested cylinders when the cascade nested cylinders are respectively used as adjusting objects, (2) identifying a current adjusting mode, obtaining the current depth of a device, determining the cascade nested cylinders used as the adjusting objects according to the current depth, controlling a motor to drive a piston to act by combining the adjusting mode, and adjusting the drainage volume of the cascade nested cylinders used as the adjusting objects. According to the method, through setting different inner diameters among the cascade nested cylinders, the cascade nested cylinders with smaller inner diameters are selected as adjustment objects to perform buoyancy control in deep water, the cascade nested cylinders with larger inner diameters are selected as adjustment objects to perform buoyancy control in shallow water, and the motor only needs to output smaller thrust to achieve buoyancy adjustment. When the antenna rises to the water surface, the buoyancy is controlled to be maximum, the height of the antenna floating out of the water surface is increased, and data transmission is facilitated.

Inventors

CHEN SHUGUO
XU MING

Assignees

中国海洋大学

Dates

Publication Date: 20260508
Application Date: 20260213

Claims (9)

1. The buoyancy adjusting method based on the multi-cascade nested cylinders is characterized in that the multi-cascade nested cylinders comprise a first cascade nested cylinder, a second cascade nested cylinder and a third cascade nested cylinder, pistons are arranged in the third cascade nested cylinder, the inner diameter of the third cascade nested cylinder is respectively smaller than the inner diameters of the first cascade nested cylinder and the second cascade nested cylinder, a motor pushes out or pulls back the pistons in the axial direction through a motor rod, when the device is in different depths under water, buoyancy adjustment is carried out through different cascade nested cylinders, a cascade nested cylinder with larger inner diameter is selected as an adjusting object for buoyancy control in shallow water, and a cascade nested cylinder with smaller inner diameter is selected as an adjusting object for buoyancy control in deep water; The buoyancy adjusting method comprises the following steps: (1) Generating a lookup table by using depth adjusting ranges corresponding to the nested cylinders at each level as adjusting objects respectively and storing the lookup table in a storage module; (2) Identifying a current adjusting mode, acquiring the current depth h of the device, determining a cascade nested cylinder serving as an adjusting object according to the current depth h, controlling a motor to drive a piston to act by combining the adjusting mode, adjusting the drainage volume of the cascade nested cylinder serving as the adjusting object, and realizing buoyancy adjustment of the device; The adjusting mode comprises a submerging adjusting mode, a self-adaptive suspension adjusting mode and a multi-cascade nested-cylinder gradient floating adjusting mode; The lower end of the third cascade nested cylinder is inserted into the second cascade nested cylinder and can axially move relative to the second cascade nested cylinder, the first cascade nested cylinder is positioned below the second cascade nested cylinder, when the motor pushes out the piston through a motor rod, the piston moves towards the bottom of the third cascade nested cylinder in the third cascade nested cylinder and can drive the third cascade nested cylinder to downwardly move relative to the second cascade nested cylinder after abutting against the bottom of the third cascade nested cylinder until the lower end of the third cascade nested cylinder penetrates out from the lower end of the second cascade nested cylinder and is inserted into the first cascade nested cylinder to axially move relative to the first cascade nested cylinder; The method comprises the steps of taking a third cascade nested cylinder as an adjusting object, adjusting the position of a piston in the third cascade nested cylinder to adjust the drainage volume of the third cascade nested cylinder, taking a second cascade nested cylinder as an adjusting object, adjusting the position of the lower end of the third cascade nested cylinder in the second cascade nested cylinder to adjust the drainage volume of the second cascade nested cylinder, and taking a first cascade nested cylinder as an adjusting object, adjusting the position of the lower end of the third cascade nested cylinder penetrating into the first cascade nested cylinder to adjust the drainage volume of the first cascade nested cylinder.
2. The buoyancy adjustment method according to claim 1, wherein when the adjustment mode is a submergence adjustment mode, the control method comprises: (211) Acquiring the set submerging suspension depth H, and inquiring the lookup table to determine an adjusting object matched with the submerging suspension depth; (212) Controlling a motor to drive a piston to act, so that the piston or a third cascade nested cylinder moves to a position corresponding to the adjusting object; (213) And acquiring the current depth H of the device in real time, comparing the current depth H with the suspension depth H, and controlling to close the motor when the current depth H is consistent with the suspension depth H, so as to keep the current state.
3. The buoyancy adjustment method according to claim 2, wherein the submergence adjustment mode further comprises controlling the motor to push out the piston when the submergence speed of the device exceeds a preset safety threshold, adjusting the amplitude Δd1, and increasing the buoyancy of the device.
4. A buoyancy adjustment method according to claim 3, wherein the submergence adjustment mode further comprises controlling the motor pull-in piston to adjust the amplitude Δd2, Δd2< "Δd1 when the submergence speed of the device falls within a safe threshold.
5. A buoyancy adjustment method according to any one of claims 2-4, wherein when the adjustment mode is an adaptive levitation adjustment mode, the control method comprises: calculating the current depth offset delta H, delta h= |h-H|; if Δh is less than or equal to 0.1H, maintaining the current regulation object and the pressure regulation pressure, and not acting; if delta H is more than 0.1H and H is more than H, controlling the motor to push out the piston, increasing a preset first drainage volume V1, continuously detecting delta H, and repeating the adjusting step until delta H is less than or equal to 0.1H; if Δh is more than 0.1H and H is less than H, controlling the motor to pull back the piston, reducing the preset second drainage volume V2, continuously detecting Δh, and repeating the fine adjustment step until Δh is less than or equal to 0.1H.
6. The buoyancy adjustment method according to claim 5, further comprising the step of calculating an electric motor extrapolation stroke from the V1, V2: The inner cavity cross-sectional area S of the current adjusting object is obtained, the stroke D1=V1/S of the motor push-out piston is controlled, and the stroke D2=V2/S of the motor pull-back piston is controlled.
7. The buoyancy adjustment method according to claim 6, wherein the current ambient water pressure P is obtained, and the thrust output by the motor is controlled to be greater than P x S.
8. The buoyancy adjustment method according to claim 5, wherein the value of V1, V2 is in the range of 0.01-0.5L.
9. A buoyancy adjustment method according to any one of claims 2 to 4 wherein when the adjustment mode is a multi-cascade nested-cylinder gradient ascent adjustment mode, the control method comprises: (221) Receiving an upward floating instruction, identifying a cascade nested cylinder which is currently used as an adjusting object, and controlling a motor to push out a piston if the cascade nested cylinder is a third cascade nested cylinder; (222) The depth of the device is obtained in real time, and when an adjusting object with the matched depth is a second cascade nested cylinder, a motor is controlled to push out a piston, so that the lower end of a third cascade nested cylinder is driven to axially move in the second cascade nested cylinder; (223) When the adjusting object matched with the depth of the device is a first cascade nested cylinder, the motor is controlled to continuously push out the piston, so that the lower end of the third cascade nested cylinder is adjusted to be inserted into the first cascade nested cylinder until the maximum stroke is reached.

Description

Buoyancy adjusting method based on multi-cascade nested cylinders Technical Field The invention belongs to the technical field of surveying, and particularly relates to a buoyancy adjusting method based on multiple cascade nested cylinders. Background The continuous buoyancy adjustment of the underwater mobile observation device comprises two methods of oil suction and drainage. For the oil sucking and discharging method, the oil in the inner oil bag and the outer oil bag is sucked by adopting an air pump and oil pump combination mode in the platform, so that the buoyancy is changed by using a method for changing the volume of the platform, and the vertical reciprocating motion of the platform is regulated. In the water sucking and draining method, a water passing valve is combined, water in the ballast water tank is drained by a high-pressure air pump to increase buoyancy, and water is injected into the ballast water tank by water pressure to reduce buoyancy. The two buoyancy adjusting methods have the technical defects that for the oil sucking and discharging method, the principle is that under the double boosting action of an air pump and an oil filling pump in the underwater moving observing device, an oil pump of an inner oil crusty pancake is driven to an outer oil crusty pancake to provide additional buoyancy, the electric structure is complex, the occupied space is large, and the oil sucking and discharging method is suitable for deep water (more than or equal to 2000 m) small-volume underwater moving observing devices (AUV, underwater gliders and the like) and is not suitable for small shallow water observing devices. Under the condition that the buoyancy adjustment range of the oil suction and discharge method is smaller (1-2L), the oil pumping speed is generally 0.003-0.02mL/s, the oil pumping time is required to exceed 4 hours, and the motor continuously works during the oil pumping period, so that the electromagnetic interference and the motion stability of the platform can be greatly and negatively influenced. The water sucking and draining method is mostly applied to the oversized equipment of the submarine, the water sucking of a plurality of water storage cabins is utilized to realize the submergence, and the water in the water storage cabins is blown out of the cabins by the high-pressure air pump to realize the floating, so that the technical problems of low adjusting speed, long adjusting time, high power consumption and low efficiency exist. If the underwater moving observation device is used for carrying out vertical profile observation in shallow sea areas with 400m, the invention needs to provide a buoyancy adjusting method which has simple structure, stability, reliability and high efficiency, and provides reciprocating power drive for the underwater small-sized underwater moving observation device, so that the observation system can carry out suspension observation at a set water depth and can timely and rapidly float up the water surface to send back data. Disclosure of Invention The invention provides a buoyancy adjusting method based on multi-cascade nested cylinders, which can solve the technical problems that the buoyancy adjusting period of the existing underwater mobile observation platform is long and continuous interference exists on a measuring device of the platform. In order to solve the technical problems, the invention is realized by adopting the following technical scheme: The buoyancy adjusting method based on the multi-cascade nested cylinders comprises a first cascade nested cylinder, a second cascade nested cylinder and a third cascade nested cylinder, wherein a piston is arranged in the third cascade nested cylinder, the inner diameter of the third cascade nested cylinder is respectively smaller than that of the first cascade nested cylinder and that of the second cascade nested cylinder, a motor pushes out or pulls back the piston through a push rod to move in the axial direction, when the device is in different depths under water, buoyancy adjustment is carried out through different cascade nested cylinders, a cascade nested cylinder with larger inner diameter is selected as an adjusting object to carry out buoyancy control in shallow water, and a cascade nested cylinder with smaller inner diameter is selected as an adjusting object to carry out buoyancy control in deep water; The buoyancy adjusting method comprises the following steps: (1) Generating a lookup table by using depth adjusting ranges corresponding to the nested cylinders at each level as adjusting objects respectively and storing the lookup table in a storage module; (2) Identifying a current adjusting mode, acquiring the current depth h of the device, determining a cascade nested cylinder serving as an adjusting object according to the current depth h, controlling a motor to drive a piston to act by combining the adjusting mode, adjusting the drainage volume of the cascade nested cylinder servin