Self-adaptive underwater holder and control method thereof

Abstract

The invention relates to the technical field of underwater operation, a Doppler water flow sensor, a position sensor, a gyroscope sensor, a full-rotation propeller thruster, a fixed propeller thruster and a control system are arranged on a cradle head shell, and the Doppler sensor is used for collecting water flow information; the position sensor and the gyroscope sensor collect holder pose information, the collected water flow information and the holder pose information serve as input quantity of the control system to be analyzed, and the control system conducts analysis according to a shooting task and a target which are set in advance and gives an instruction to the propeller to be matched with water flow to change the position of the holder. According to the underwater cradle head, when the water flow state meets the shooting requirement, the direction of the underwater cradle head can be adjusted through water flow, so that the power of the driving motor of the propeller is reduced, the consumption of electric energy in the shooting process is greatly reduced, the effect of saving energy consumption is achieved, and then the cruising ability of the cradle head is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of underwater operations, and in particular to an adaptive underwater pan / tilt platform and a control method thereof. Background Art

[0002] Most of the existing underwater shooting operations use underwater pan / tilts to assist in shooting. Traditional underwater pan / tilts are usually composed of sensors, control systems, drive systems, and working systems. Sensors include gyroscope sensors for monitoring the tilt angle and angular velocity of the camera, and position sensors for monitoring the rotation angle and position of the camera. The operator receives information from the sensor and issues control instructions for the direction, speed, and angle of the camera's movement through the control system. The drive system converts the received control signal into an electrical signal, drives the transmission device through a DC motor, and operates the rotating axis to make the camera reach the specified posture. Traditional underwater pan / tilts use batteries for battery life.

[0003] Due to structural limitations, the existing underwater gimbal cannot have a larger battery capacity, and the low temperature environment underwater will cause the actual battery capacity to further decrease. When the existing underwater gimbal is working, the control system needs to operate the drive motor frequently to adjust the angle. Purely relying on the drive motor to adjust the angle of the underwater gimbal consumes a lot of electricity, resulting in insufficient battery life. Therefore, an adaptive underwater gimbal that can combine the water flow factors around the gimbal to improve battery life is needed to solve the above problems. Summary of the invention

[0004] The problem to be solved by the present invention is that the angle of the underwater pan / tilt needs to be adjusted frequently, and the angle adjustment of the underwater pan / tilt is purely dependent on a driving motor, which consumes a lot of power.

[0005] In order to achieve the above object, the present invention provides an adaptive underwater pan / tilt platform and a control method thereof:

[0006] An adaptive underwater pan-tilt platform, comprising a pan-tilt platform housing and a power propulsion system, a detection component, a power supply device and a control system connected to the pan-tilt platform housing;

[0007] The pan / tilt housing is a housing structure that is hollow and sealed inside;

[0008] The power propulsion system is installed on the outside of the pan / tilt housing, and the power propulsion system enables the underwater pan / tilt to realize any one of the following movements or any combination of posture adjustment: forward, backward, left turn, right turn, fixed-point rotation, floating, diving, and left and right translation;

[0009] The detection component includes a position sensor, a water flow sensor and a gyroscope sensor installed on the pan / tilt housing, wherein the position sensor and the water flow sensor are both arranged at the front end of the pan / tilt housing, and the gyroscope sensor is installed at the rear end inside the pan / tilt housing;

[0010] The power supply device is installed inside the pan / tilt housing to provide power to the power propulsion system, the position sensor, the water flow sensor, the gyroscope sensor, and the control system;

[0011] The control system is installed inside the pan / tilt housing, and the control system transmits signals with the power propulsion system, the position sensor, the water flow sensor, and the gyroscope sensor;

[0012] The control system is configured to:

[0013] According to the water flow information provided by the water flow sensor and the underwater pan-tilt posture information provided by the gyroscope sensor and the position sensor, the power propulsion system is controlled to use the water flow to adjust the underwater pan-tilt posture.

[0014] Preferably, the detection body of the position sensor is installed in the gimbal shell, the detection probe of the position sensor extends outside the gimbal shell and is sealed with the gimbal shell, and the detection body of the water flow sensor is installed in the gimbal shell, the detection probe of the water flow sensor extends outside the gimbal shell and is sealed with the gimbal shell.

[0015] Preferably, the power propulsion system includes a horizontal propulsion system and a vertical propulsion system; the gimbal housing has a first centerline and a second centerline extending in the horizontal direction and perpendicular to each other;

[0016] The horizontal propulsion system includes four groups of azimuth propeller thrusters installed at the lower end of the pan / tilt housing, the vertical rotation axis of the azimuth propeller thrusters is arranged along the vertical direction of the pan / tilt housing and can rotate 360° in the horizontal direction to achieve the posture adjustment of the underwater pan / tilt in the horizontal direction;

[0017] Two groups of the fully rotating propeller thrusters are arranged at the front end of the gimbal housing, namely the front left propeller and the front right propeller, and the other two groups of the fully rotating propeller thrusters are arranged at the rear end of the gimbal housing, namely the rear left propeller and the rear right propeller, wherein the front left propeller and the front right propeller are symmetrically arranged about the second center line, the rear left propeller and the rear right propeller are symmetrically arranged about the second center line, the front left propeller and the rear left propeller are symmetrically arranged along the first center line, and the front right propeller and the rear right propeller are symmetrically arranged about the first center line;

[0018] The vertical propulsion system includes a left propeller and a right propeller installed at the upper end of the pan / tilt housing, and the rotating shafts of the propellers of the left propeller and the right propeller are both arranged vertically to adjust the vertical posture of the underwater pan / tilt;

[0019] The left propeller and the right propeller are symmetrically arranged about the second center line and are arranged on the first center line;

[0020] The connections between the four groups of fully-rotating propeller thrusters and the gimbal housing, and the connections between the left thruster and the right thruster and the gimbal housing are all sealed.

[0021] Preferably, mechanical seals are used at the connections between the four groups of fully-rotating propeller thrusters, the left thruster, the right thruster and the gimbal housing.

[0022] Preferably, the fully-rotating propeller propeller has a first drive motor for driving the vertical rotating shaft to rotate and a second drive motor for driving the propeller blades to rotate, and the fixed propeller propeller has a third drive motor for driving the propeller blades to rotate, the first drive motor, the second drive motor and the third drive motor are all installed in the gimbal housing, the first drive motor, the second drive motor and the third drive motor are all DC encoded reduction motors, the first drive motor, the second drive motor and the third drive motor are all electrically connected to the power supply, and the first drive motor, the second drive motor and the third drive motor are all connected to the control system for signal transmission.

[0023] Preferably, the power supply is a DC generator installed inside the gimbal shell, the power supply has a power switch, the power switch is installed on the outside of the gimbal shell and sealed to the gimbal shell, the power supply is electrically connected to the position sensor, the water flow sensor, the gyroscope sensor, the power supply, the power propulsion system and the control system.

[0024] Preferably, the detection probe of the position sensor is sealed to the pan-tilt housing by sealant, and the detection probe of the water flow sensor is sealed to the pan-tilt housing by sealant.

[0025] Preferably, it also includes a magnetic platform, which is installed at the upper end of the pan / tilt housing, and a magnet for fixing the camera is installed at the center of the magnetic platform.

[0026] Preferably, it also includes an illuminator, which is installed at the front end of the pan / tilt housing and is electrically connected to the power supply.

[0027] A method for controlling an adaptive underwater pan / tilt platform, characterized in that it comprises the following steps:

[0028] Step 1: Measure the water flow speed and direction at the position of the gimbal shell by a water flow sensor to obtain the water flow rate, and then obtain the water flow resistance information; collect the posture information of the gimbal shell by a gyroscope sensor and a position sensor, wherein the gyroscope sensor collects the posture deviation of the gimbal, and the position sensor collects the distance deviation of the gimbal shell;

[0029] Step 2: The control system performs fuzzy control on the posture information detected by the gyro sensor and the position sensor to obtain an accurate control amount;

[0030] Step 3: The control system receives the current water flow resistance information, and combines the precise control amount of the position information of the gimbal shell. The control system analyzes and issues instructions to the power propulsion system to change the gimbal position according to the previously set shooting tasks and targets;

[0031] When it is determined that water flow can be used to assist in driving the pan / tilt head to rotate, the control system controls the power propulsion system to adjust the direction of the pan / tilt head shell with less power, and enables the pan / tilt head shell to remain relatively still with the shooting target; when it is determined that the water flow direction is opposite to the shooting direction, the shooting is carried out after waiting for the water flow direction to change or the water flow resistance to weaken.

[0032] Step 4: Repeat steps 1 to 3 above according to the changes in the water flow speed and direction.

[0033] The present invention arranges a Doppler water flow sensor, a position sensor, a gyroscope sensor, an azimuth propeller thruster, a fixed propeller thruster and a control system on a pan / tilt housing, utilizes the Doppler sensor to collect water flow information, utilizes the position sensor and the gyroscope sensor to collect pan / tilt posture information, and the collected water flow information and pan / tilt posture information are analyzed as input quantities of the control system, and the control system analyzes according to previously set shooting tasks and targets, determines whether the water flow direction is the same or different from the shooting direction, and issues instructions to the azimuth propeller thruster and the fixed propeller thruster to change the pan / tilt position in coordination with the water flow, and when the water flow state of the underwater pan / tilt meets the shooting requirements, the water flow can be used to adjust the direction of the underwater pan / tilt, so that the power of the driving motor of the thruster can be reduced, thereby greatly reducing the consumption of electric energy during the shooting process, achieving the effect of saving energy consumption, and further improving the endurance of the pan / tilt. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a top view of the adaptive underwater pan / tilt platform of the present invention.

[0035] Figure 2 It is a rear view of the adaptive underwater pan / tilt platform of the present invention.

[0036] Figure 3 It is a left view of the adaptive underwater platform of the present invention.

[0037] Figure 4 It is a principle flow chart of the adaptive underwater pan / tilt platform of the present invention.

[0038] Figure 5 It is a flow chart of the fuzzy control principle of the adaptive underwater pan-tilt platform of the present invention.

[0039] In the figure, 1. gimbal housing; 2. power propulsion system; 201. full-rotation propeller thruster; 2011. front left thruster; 2012. front right thruster; 2013. rear left thruster; 2014. rear right thruster; 2021. left thruster, 2022. right thruster; 3. detection component; 301. position sensor; 302. water flow sensor; 303. gyroscope sensor; 4. power supply; 5. control system; 6. power switch; 7. magnetic suction platform; 8. magnet; 9. illuminator. DETAILED DESCRIPTION

[0040] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0041] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information.

[0042] like Figure 1-5 As shown, an adaptive underwater pan-tilt platform according to a preferred embodiment of the present invention comprises a pan-tilt platform housing 1 and a power propulsion system 2, a detection component 3, a power supply 4 and a control system 5 connected to the pan-tilt platform housing 1;

[0043] The pan / tilt housing 1 is a hollow and sealed housing structure. The appearance of the pan / tilt housing 1 is a circular structure with a streamlined design. The entire structure is made of aluminum alloy with a waterproof and anti-corrosion coating on the surface. While ensuring the pan / tilt housing 1 is light, the resistance to water flow impact is effectively reduced.

[0044] The power propulsion system 2 is installed on the outside of the pan / tilt housing 1. The power propulsion system 2 enables the pan / tilt housing 1 to realize any one of the movements or any combination of the movements, including forward, backward, left turn, right turn, fixed-point rotation, upward, downward, and left and right translation. The purpose of the power propulsion system 2 in realizing any one of the above movements or any combination of the above movements is to keep the camera connected thereto and the object to be photographed in a relatively static state;

[0045] The detection component 3 includes a position sensor 301, a water flow sensor 302 and a gyroscope sensor 303 installed on the pan / tilt housing 1, wherein the water flow sensor 302 is a Doppler water flow sensor, which uses the Doppler effect of sound waves in the water flow to measure the water flow speed and direction. The basic principle is that the Doppler sensor transducer transmits an ultrasonic signal into the water. When the ultrasonic signal encounters suspended particles, bubbles or other tiny scatterers in the water, it will be reflected back. Due to the flow of water, a Doppler frequency shift is generated, so that the water flow rate is calculated using a formula. The water flow rate is combined with the area of ​​the force-bearing surface of the underwater pan / tilt in the direction of the water flow to calculate the water flow per unit area, thereby calculating the water resistance information. The specific calculation method will be described below.

[0046] The position sensor 301 and the water flow sensor 302 are both arranged at the front end of the pan-tilt housing 1. The position sensor 301 and the water flow sensor 302 are respectively located on the left and right sides of the front end of the pan-tilt housing 1, and are symmetrically arranged on the left and right sides. The detection body of the position sensor 301 is installed in the pan-tilt housing 1. The detection probe of the position sensor 301 extends to the outside of the pan-tilt housing 1 and is sealed and connected to the pan-tilt housing 1. The detection probe of the position sensor 301 extends to the outside of the pan-tilt housing 1, and the detection purpose is achieved when the detection probe contacts the external water flow. A positioning installation hole matched with the detection probe is provided on the pan-tilt housing 1. The detection probe penetrates the positioning installation hole, and the transducer detected by it is placed outside the pan-tilt housing 1. The detection probe and the positioning installation hole are sealed and connected by sealant to prevent water outside the pan-tilt housing 1 from entering the pan-tilt housing 1 through the position of the positioning installation hole. The position sensor 301 adopts an ultrasonic type, and obtains the position information of the pan-tilt by emitting ultrasonic waves. The position sensor 301 is used to measure the distance information of the pan-tilt. The information collected by the position sensor 301 is transmitted to the control system 5 as input;

[0047] The detection body of the water flow sensor 302 is installed in the pan-tilt shell 1, and the detection probe of the water flow sensor 302 extends to the outside of the pan-tilt shell 1 and is sealed and connected to the pan-tilt shell 1. The detection probe of the water flow sensor 302 extends to the outside of the pan-tilt shell 1, and the detection purpose is achieved when the detection probe contacts the external water flow. A positioning and mounting hole that cooperates with the detection probe is provided on the pan-tilt shell 1. The detection probe penetrates the positioning and mounting hole, and the transducer for detection is placed outside the pan-tilt shell 1. The detection probe and the positioning and mounting hole are sealed and connected by sealant to prevent water outside the pan-tilt shell 1 from entering the pan-tilt shell 1 through the position of the positioning and mounting hole. The water flow sensor 302 adopts a Doppler water flow sensor 302, which uses the Doppler effect of sound waves in the water flow to measure the water flow speed and direction. The sensor transducer transmits an ultrasonic signal into the water. When the ultrasonic signal encounters suspended particles, bubbles or other tiny scatterers in the water, it will be reflected back. Due to the flow of water, the above-mentioned objects and the ultrasonic source move relative to each other, and the frequency of the reflected ultrasonic signal will change, and the change amount is the Doppler frequency shift fd. By measuring the Doppler frequency shift fd, and combining the installation angle θ of the sensor, the propagation speed c of the ultrasonic wave in water and other parameters, the water flow rate can be calculated. The specific formula is: flow rate = Doppler frequency shift fd×c / (2×f0×cosθ). Among them, θ is the angle between the ultrasonic beam and the water flow direction, fd is the Doppler frequency shift, c is the propagation speed of the ultrasonic wave in water, and f0 is the transmission frequency. After measuring the speed of the water flow, combined with the area of ​​the water body, the water flow rate is obtained, and then the resistance information of the water flow is obtained. The resistance information is transmitted to the control system 5 as input;

[0048] The gyro sensor 303 is installed at the rear end of the gimbal housing 1. The gyro sensor 303 has three sensitive axes: X, Y, and Z. When the gimbal direction changes, a torque will be generated in these directions due to the law of conservation of angular momentum. The sensor measures the angular displacement and angular velocity of the gimbal by collecting the torque. The attitude deviation of the gimbal is measured by the gyro sensor 303. The attitude deviation information collected by the gyro sensor 303 is transmitted to the control system 5 as an input.

[0049] The power supply device 4 is installed inside the pan / tilt housing 1. The power supply device 4 can use a DC generator or a DC battery as a system power supply to provide power for the power propulsion system 2, the position sensor 301, the water flow sensor 302, the gyroscope sensor 303, and the control system 5. The power supply device 4 has a power switch 6. The power switch 6 is installed on the outside of the pan / tilt housing 1 and is sealed to the pan / tilt housing 1. The power switch 6 is a push-type, and the outside is waterproof and sealed with a plastic film. The power switch 6 is the main switch of the entire device, which is used to control the opening and closing of the pan / tilt;

[0050] The control system 5 is installed inside the pan-tilt housing 1, and the control system 5 transmits signals with the power propulsion system 2, the position sensor 301, the water flow sensor 302, and the gyroscope sensor 303. The control system 5 is configured as follows: the control system 5 controls the power propulsion system 2 to adjust the position of the underwater pan-tilt using the water flow according to the water flow information provided by the water flow sensor 302 and the position information of the pan-tilt housing 1 provided by the gyroscope sensor 303 and the position sensor 301;

[0051] The control system 5 is the core part of the whole adaptive collaborative work, which specifically uses the fuzzy control principle; the specific process is as shown in the attached Figure 3 As shown, first, the attitude deviation of the gimbal detected by the position sensor 301, such as the pitch angle deviation, the roll angle deviation and the rate of change of the deviation, is fuzzified and converted into fuzzy quantities such as "left large (LL)", "right small (RS)" and "zero (ZO)". At the same time, a fuzzy rule base is established. For example, if the pitch angle deviation of the gimbal is left large (LL), then the power propulsion system obtains the control instruction right large (RL). Then, according to the rule, the input fuzzy quantity is calculated by the Sugeno method, and the membership μ corresponding to the above input quantity in the fuzzy set is calculated. Then, the excitation intensity is determined by the minimum operation, and the excitation intensity is multiplied by the fuzzy rule function to obtain the output value z. Finally, the obtained output quantity is defuzzified using the centroid method. Specifically, the domain of the output value z is set to [zmin, zmax], and for each value zi in the domain, the corresponding membership is μ(zi). Add the product of each value zi and the corresponding membership μ(zi), and then divide it by the sum of the memberships to get an accurate control value z*, so as to achieve accurate adjustment of the gimbal attitude;

[0052] After receiving the water flow information from the water flow sensor 302, the control system 5 will analyze it according to the previously set shooting tasks and targets. When it is determined that the water flow can be used to assist in driving the pan-tilt head to rotate, the control system 5 only needs to issue a command to let the propulsion system 2 adjust the direction of the pan-tilt head with less power so that the camera can accurately aim at the target; when it is determined that the water flow direction is opposite to the shooting direction, the shooting work will be carried out after the water flow direction changes or the resistance is reduced. During the shooting process, the speed and direction of the water flow may change. The water flow sensor 302 will continue to monitor these changes and feed back new data to the control system 5 through the water flow sensor 302. The control system 5 will analyze and adjust again according to the new data to adjust the position and posture of the underwater pan-tilt head;

[0053] Specifically, the power propulsion system 2 includes a horizontal propulsion system and a vertical propulsion system. The horizontal propulsion system can propel the gimbal at multiple angles in the horizontal direction, and the vertical propulsion system propels the gimbal in the vertical direction. The two cooperate to realize any one of the following movements or any combination of movements: forward, backward, left turn, right turn, fixed-point rotation, upward, downward, and left and right translation, so that the gimbal and the object being photographed always remain stationary.

[0054] The horizontal propulsion system includes four groups of azimuth propeller thrusters 201 installed at the lower end of the pan / tilt housing 1. The vertical rotation axis of the azimuth propeller thrusters 201 is arranged along the vertical direction of the pan / tilt housing 1 and can rotate 360° in the horizontal direction. The azimuth propeller thrusters 201, also known as Z-shaped thrusters, Z-axis propellers, omnidirectional thrusters, rudder thrusters, steering propellers, and gyratory propellers, can make the propellers or duct thrusters rotate 360° around the vertical axis in the horizontal plane through the bevel gear system transmission mechanism to propel and manipulate the pan / tilt. Because its shaft system is arranged in a Z shape, it can simultaneously propel and manipulate the pan / tilt. The azimuth propeller can arbitrarily change the direction of thrust, so that the pan / tilt can turn around on the spot and move forward and backward freely. One set of driving forces is input to the propeller blades on the full-revolving propeller propeller 201 through the power of the Z-shaped shaft system. The source of this set of driving forces is the second driving motor installed in the pan-tilt housing 1. The outer side of the second driving motor is coated with a waterproof coating. The source of the driving force of the worm-wheel system for the full-revolving propeller propeller 201 to rotate 360 ​​degrees horizontally is the first driving motor installed in the pan-tilt housing 1. The outer side of the second driving motor is coated with a waterproof coating. Mechanical seals are provided between the structures of the two rotating parts of the full-revolving propeller propeller 201 and the pan-tilt housing 1 to prevent water from entering the pan-tilt housing 1 from outside the pan-tilt housing 1. The first driving motor and the second driving motor are both DC encoder reduction motors;

[0055] Specifically, the output power of the full-rotation propeller thruster 201 rotates the vertical shaft through the first-stage bevel gear, and is then transmitted to the thruster through the second-stage bevel gear, forming a Z-shaped transmission system. A drive unit is also provided to drive the worm gear to drive the entire thruster device to make a 360° horizontal rotation. The Z-shaped shaft system and the guide duct propeller are all installed on a cylindrical body. The steering propeller has a large unit horsepower thrust and good maneuverability. The tugboat equipped with dual omnidirectional thrusters has the ability to rotate, translate, and reverse on the spot, thereby driving the underwater gimbal to achieve a combination of forward, backward, left turn, right turn, fixed-point rotation, and left and right translation. The backward thrust is basically the same as the forward thrust, and the aircraft can be operated by remote control. A mesh cover is installed in front of the duct to protect the propeller.

[0056] Two sets of fully rotating propeller thrusters 201 are arranged at the front end of the gimbal housing 1, namely, the front left propeller 2011 and the front right propeller 2012, and the other two sets of fully rotating propeller thrusters 201 are arranged at the rear end of the gimbal housing 1, namely, the rear left propeller 2013 and the rear right propeller 2014, the front left propeller 2011 and the front right propeller 2012 are arranged symmetrically along the second center line Y, and the rear left propeller 2013 and the rear right propeller 2014 are arranged symmetrically along the second center line Y. Symmetrical arrangement, the front left propeller 2011 and the rear left propeller 2013 are symmetrically arranged along the first center line X, the front right propeller 2012 and the rear right propeller 2014 are symmetrically arranged along the first center line X, and the four groups of full-rotation propeller thrusters 201 are symmetrically arranged along the center in front and back and left and right directions. The position of the gimbal housing 1 in the horizontal direction is changed by driving the motor, and the position of the gimbal in the horizontal direction is changed by changing the driving power and driving angle of the full-rotation propeller thrusters 201 at different positions;

[0057] The vertical propulsion system includes a left propeller 2021 and a right propeller 2022 installed at the upper end of the pan-tilt housing 1. The left propeller 2021 and the right propeller 2022 are both fixed propeller propellers. The rotating shafts of the propellers of the left propeller 2021 and the right propeller 2022 are both arranged vertically, which are used to adjust the vertical posture of the underwater pan-tilt. The left propeller 2021 and the right propeller 2022 are symmetrically arranged about the second center line Y and are arranged on the first center line X; the stirring direction is arranged downward, so as to adjust the underwater pan-tilt to achieve the movement of floating and diving; the connection between the four groups of fully rotating propeller propellers 201 and the pan-tilt housing 1, and the connection between the left propeller 2021 and the right propeller 2022 and the pan-tilt housing 1 are all sealed. Specifically, the connection between the four groups of fully rotating propeller propellers 201, the left propeller 2021 and the right propeller 2022 and the pan-tilt housing 1 is mechanically sealed.

[0058] The left propeller 2021 is arranged between the front left propeller 2011 and the rear left propeller 2013, and the right propeller 2022 is arranged between the front right propeller 2012 and the rear right propeller 2014. The left propeller 2021 and the right propeller 2022 both have a third drive motor for driving the propeller blades to rotate. The third drive motor is installed in the gimbal housing 1. The third drive motor is a DC encoder reduction motor. Each drive motor is electrically connected to a DC generator or a DC power supply, and each drive motor is connected to the control system 5 for signal transmission.

[0059] This embodiment further includes a magnetic platform 7, which is mounted on the upper end of the pan / tilt housing 1, and a magnet 8 for fixing the camera is mounted at the center of the magnetic platform 7;

[0060] It also includes an illuminator 9, which is installed at the front end of the pan / tilt housing 1. The illuminator 9 is electrically connected to a DC generator or a DC power supply, and the illuminator 9 provides the light source required for shooting.

[0061] A method for controlling an adaptive underwater pan / tilt platform comprises the following steps:

[0062] Step 1: Measure the water flow speed and direction at the current position of the pan / tilt housing 1 through the water flow sensor 302 to obtain the water flow rate, and then obtain the water flow resistance information;

[0063] When the ultrasonic signal emitted by the water flow sensor 302 encounters suspended particles, bubbles or other tiny scatterers in the water, it will be reflected back, and the flow of water will produce a Doppler frequency shift f d , combined with the installation angle θ of the water flow sensor 302, the propagation speed c of ultrasonic waves in water, and the ultrasonic frequency f0, the current water flow rate is calculated as follows:

[0064] Flow rate = f d ×c / (2×f0×cosθ);

[0065] The water flow velocity is obtained, and combined with the area of ​​the force-bearing surface of the underwater gimbal in the direction of the water flow, the water flow rate is obtained, and then the resistance information of the water flow is obtained;

[0066] At the same time, the gimbal posture information is collected through the gyro sensor 303 and the position sensor 301, wherein the gyro sensor 303 collects the posture deviation of the gimbal, and the position sensor 301 collects the distance deviation of the gimbal;

[0067] The gyro sensor 303 has three sensitive axes, X, Y, and Z. When the direction of the gimbal changes, torques are generated in these directions due to the law of conservation of angular momentum. The gyro sensor 303 collects the torques to measure the angular displacement and angular velocity of the gimbal.

[0068] The position sensor 301 is of ultrasonic type and obtains the position information of the pan / tilt head by generating ultrasonic waves;

[0069] Step 2: The control system 5 performs fuzzy control on the posture information detected by the gyro sensor 303 and the position sensor 301 to obtain an accurate control amount;

[0070] First, the attitude deviation of the gimbal detected by the position sensor 301, such as the pitch angle deviation, roll angle deviation and the rate of change of the deviation, is fuzzified and converted into fuzzy quantities such as "left large (LL)", "right small (RS)" and "zero (ZO)". At the same time, a fuzzy rule base is established. For example, if the pitch angle deviation of the gimbal is left large (LL), then the motor obtains the control instruction right large (RL). Then, according to the rule, the input fuzzy quantity is calculated by the Sugeno method. First, the membership degree μ corresponding to the above input quantity in the fuzzy set is calculated, and then the excitation intensity is determined by taking the minimum operation. The excitation intensity is multiplied by the fuzzy rule function to obtain the output value z. Finally, the obtained output quantity is defuzzified using the centroid method. Suppose the domain of the output value z is [zmin, zmax], and for each value zi in the domain, the corresponding membership degree is μ(zi). Add the product of each value zi and the corresponding membership μ(zi), and then divide it by the sum of the memberships to obtain an accurate control value z*, which is convenient for the subsequent precise adjustment of the gimbal attitude.

[0071] Step 3: The control system 5 receives the current water flow resistance information, and combined with the precise control amount of the precise position information of the gimbal, the control system 5 will analyze and issue instructions to the propulsion system 2 to change the gimbal position according to the previously set shooting tasks and goals;

[0072] When it is determined that water flow can be used to assist in driving the pan-tilt head to rotate, the control system 5 issues an instruction to control the driving device of the power propulsion system 2 to adjust the direction of the pan-tilt head with less power so that the pan-tilt head can remain relatively still with the shooting target; when it is determined that the direction of the water flow is opposite to the shooting direction, the control system 5 will appropriately increase the power of the driving device of the power propulsion system 2 to overcome the resistance based on the water flow information, or wait for the water flow direction to change or the resistance to weaken before shooting.

[0073] Step 4: During the shooting process, the speed and direction of the water flow may change. Repeat steps 1 to 3 above.

[0074] The present invention arranges a Doppler water flow sensor, a position sensor, a gyroscope sensor, an azimuth propeller thruster, a fixed propeller thruster and a control system on a pan / tilt housing, utilizes the Doppler sensor to collect water flow information, utilizes the position sensor and the gyroscope sensor to collect pan / tilt posture information, and the collected water flow information and pan / tilt posture information are analyzed as input quantities of the control system, and the control system analyzes according to previously set shooting tasks and targets, determines whether the water flow direction is the same or different from the shooting direction, and issues instructions to the azimuth propeller thruster and the fixed propeller thruster to change the pan / tilt position in coordination with the water flow, and when the water flow state of the underwater pan / tilt meets the shooting requirements, the water flow can be used to adjust the direction of the underwater pan / tilt, so that the power of the driving motor of the thruster can be reduced, thereby greatly reducing the consumption of electric energy during the shooting process, achieving the effect of saving energy consumption, and further improving the endurance of the pan / tilt.

[0075] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. An adaptive underwater pan / tilt head, characterized in that: It comprises a pan / tilt housing (1), and a power propulsion system (2), a detection component (3), a power supply device (4), and a control system (5) connected to the pan / tilt housing (1); The pan / tilt housing (1) is a housing structure that is hollow and sealed; The power propulsion system (2) is installed on the outside of the pan / tilt housing (1), and the power propulsion system (2) enables the underwater pan / tilt to realize any one of the following movements, or any combination of several movements, including forward movement, backward movement, left turn, right turn, fixed-point rotation, upward movement, downward movement, and left / right translation. The detection component (3) comprises a position sensor (301), a water flow sensor (302) and a gyroscope sensor (303) installed on the pan / tilt housing (1); the position sensor (301) and the water flow sensor (302) are both arranged at the front end of the pan / tilt housing (1), and the gyroscope sensor (303) is installed at the rear end inside the pan / tilt housing (1); The power supply device (4) is installed inside the pan / tilt housing (1) to provide power to the power propulsion system (2), the position sensor (301), the water flow sensor (302), the gyroscope sensor (303), and the control system (5); The control system (5) is installed inside the pan / tilt housing (1), and the control system (5) transmits signals with the power propulsion system (2), the position sensor (301), the water flow sensor (302), and the gyroscope sensor (303); The control system (5) is configured as follows: Based on the water flow information provided by the water flow sensor (302) and the underwater pan / tilt posture information provided by the gyro sensor (303) and the position sensor (301), the power propulsion system (2) is controlled to use the water flow to adjust the underwater pan / tilt posture.

2. The adaptive underwater pan / tilt platform according to claim 1, characterized in that: The detection body of the position sensor (301) is installed in the pan-tilt housing (1), the detection probe of the position sensor (301) extends to the outside of the pan-tilt housing (1) and is sealed to the pan-tilt housing (1), and the detection body of the water flow sensor (302) is installed in the pan-tilt housing (1), the detection probe of the water flow sensor (302) extends to the outside of the pan-tilt housing (1) and is sealed to the pan-tilt housing (1).

3. The adaptive underwater pan / tilt platform according to claim 1, characterized in that: The power propulsion system (2) comprises a horizontal propulsion system and a vertical propulsion system; the gimbal housing (1) has a first centerline (X) and a second centerline (Y) extending in the horizontal direction and perpendicular to each other; The horizontal propulsion system comprises four groups of azimuthally revolving propeller thrusters (201) mounted at the lower end of the pan / tilt housing (1); the vertical rotation axes of the azimuthally revolving propeller thrusters (201) are arranged vertically along the pan / tilt housing (1) and can rotate 360° in the horizontal direction, so as to achieve horizontal posture adjustment of the underwater pan / tilt; Two groups of the azimuth propeller thrusters (201) are arranged at the front end of the gimbal housing (1), namely the front left propeller (2011) and the front right propeller (2012); another two groups of the azimuth propeller thrusters (201) are arranged at the rear end of the gimbal housing (1), namely the rear left propeller (2013) and the rear right propeller (2014); wherein the front left propeller (2011) and the front right propeller (2012) are symmetrically arranged about the second center line (Y); the rear left propeller (2013) and the rear right propeller (2014) are symmetrically arranged about the second center line (Y); the front left propeller (2011) and the rear left propeller (2013) are symmetrically arranged along the first center line (X); and the front right propeller (2012) and the rear right propeller (2014) are symmetrically arranged about the first center line (X); The vertical propulsion system comprises a left propeller (2021) and a right propeller (2022) mounted on the upper end of the pan / tilt housing (1); the rotating shafts of the propellers of the left propeller (2021) and the right propeller (2022) are both arranged vertically, and are used to adjust the vertical posture of the underwater pan / tilt; The left propeller (2021) and the right propeller (2022) are symmetrically arranged about the second center line (Y), and are arranged on the first center line (X); The connection points between the four groups of fully rotating propeller thrusters (201) and the pan-tilt housing (1), and the connection points between the left thruster (2021) and the right thruster (2022) and the pan-tilt housing (1) are all sealed.

4. The adaptive underwater pan / tilt platform according to claim 3, characterized in that: Mechanical seals are used at the connections between the four groups of fully rotating propeller thrusters (201), the left thruster (2021), and the right thruster (2022) and the pan / tilt housing (1).

5. The adaptive underwater pan / tilt platform according to claim 4, characterized in that: The fully-rotating propeller thruster (201) has a first drive motor for driving the vertical rotating shaft to rotate and a second drive motor for driving the propeller blades to rotate; the left propeller (2021) and the right propeller (2022) both have a third drive motor for driving the propeller blades to rotate, the first drive motor, the second drive motor and the third drive motor are all installed in the gimbal housing (1), the first drive motor, the second drive motor and the third drive motor are all DC encoding reduction motors, the first drive motor, the second drive motor and the third drive motor are all electrically connected to the power supply (4), and the first drive motor, the second drive motor and the third drive motor are all connected to the control system (5) for signal transmission.

6. The adaptive underwater pan / tilt platform according to claim 1, characterized in that: The power supply device (4) is a DC generator installed inside the pan-tilt housing (1). The power supply device (4) has a power switch (6). The power switch (6) is installed on the outside of the pan-tilt housing (1) and is sealed to the pan-tilt housing (1). The power supply device (4) is electrically connected to the position sensor (301), the water flow sensor (302), the gyroscope sensor (303), the power supply device (4), the power propulsion system (2) and the control system (5).

7. The adaptive underwater pan / tilt platform according to claim 2, characterized in that: The detection probe of the position sensor (301) is sealed and connected to the pan-tilt housing (1) by means of sealant, and the detection probe of the water flow sensor (302) is sealed and connected to the pan-tilt housing (1) by means of sealant.

8. The adaptive underwater pan / tilt platform according to claim 1, characterized in that: It also comprises a magnetic attraction platform (7), which is mounted on the upper end of the pan / tilt housing (1), and a magnet (8) for fixing a camera is mounted at the center of the magnetic attraction platform (7).

9. The adaptive underwater pan / tilt platform according to claim 1, characterized in that: It also comprises an illuminator (9), which is mounted on the front end of the pan / tilt housing (1), and the illuminator (9) is electrically connected to the power supply (4).

10. A control method for an adaptive underwater pan / tilt platform according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: using a water flow sensor (302) to measure the water flow speed and direction at the position of the gimbal housing (1) to obtain the water flow rate, and then obtain the water flow resistance information; using a gyroscope sensor (303) and a position sensor (301) to collect the position information of the gimbal housing (1), wherein the gyroscope sensor (303) collects the posture deviation of the gimbal, and the position sensor (301) collects the distance deviation of the gimbal housing (1); Step 2: The control system (5) performs fuzzy control on the posture information detected by the gyro sensor (303) and the position sensor (301) to obtain an accurate control amount; Step 3: The control system (5) receives the current water flow resistance information, and combines it with the precise control amount of the position information of the gimbal housing (1). The control system (5) analyzes and issues instructions to the power propulsion system (2) to change the gimbal position according to the previously set shooting tasks and targets; When it is determined that the pan / tilt head can be driven to rotate with the assistance of water flow, the control system (5) controls the power propulsion system (2) to adjust the direction of the pan / tilt head housing (1) with a relatively small power, and enables the pan / tilt head housing (1) to remain relatively still with respect to the photographed target; when it is determined that the direction of the water flow is opposite to the photographing direction, the photographing operation is performed after the direction of the water flow changes or the water flow resistance is reduced; Step 4: Repeat steps 1 to 3 above according to the changes in the water flow speed and direction.

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