Remotely operated unmanned underwater vehicle

Abstract

The invention relates to a remotely operated unmanned underwater vehicle and communication system that can be controlled remotely in the underwater environment. This invention focuses on the development of a new inspection class category ROV of 6 DOF, which overcomes some of the disadvantages of existing ROVs of the same category in both design and function.

Description

[0001] REMOTELY OPERATED UNMANNED UNDERWATER VEHICLE

[0002] Technical field of the invention

[0003] The invention relates to a remotely operated unmanned underwater vehicle and communication system that can be controlled remotely in the underwater environment. This invention focuses on the development of a new inspection class category ROV of 6 DOF, which overcomes some of the disadvantages of existing ROVs of the same category in both design and function.

[0004] State of the Art

[0005] In general, the most important requirements for the development of the inspection class category are increasing manoeuvrability and reducing energy consumption and costs; here these three parameters are discussed in detail. Manoeuvrability is mainly affected by two factors: thrusters and hull design (shape, size, dry room and air tanks), energy consumption is mainly affected by water resistance forces during movement (drag, lift and slide), and cost is affected by the selected components of the system. The use of reconfigurable thrusters (RT) will increase the manoeuvrability of ROVs (remotely operated vehicles) with less thrust. Using fixed thrusters (FT) will reduce design complexity and increase their reliability due to fewer moving parts. This makes this configuration a favourite choice among many ROV designers.

[0006] To guarantee the highest level of manoeuvrability, it is known that at least 6 FT is required for manoeuvring in 6 Degrees of Freedom (DOF): Y, X, Z, pitch, roll and yaw. However, it has been noticed that not all 6 DOF designs have the ability to rotate freely around their rotation axes. UUVs with air tanks on top do not have the ability to rotate freely around all their axes due to the resistive torque produced by these air tanks to keep the UUV in planar orientation. Spherical UUV systems can rotate freely around their spin axes because their Centre of Mass is usually located at the centre of the body. There also are some UUVs that are non-spherical and can rotate freely around their axis because their dry chambers are located in the centre of the body and do not have additional air tanks. Open body designs may have lower water resistance forces than closed body designs; however, closed body designs are much more reliable during navigation as there is little chance of them getting stuck on any object in the working environment.

[0007] The invention that is the subject of the application numbered "LIS2021163107” in the state of the art relates to remotely operated vehicles and / or autonomous underwater vehicles. The invention comprises a vehicle body with a centre, a front, a rear, sides, top and bottom. There are multiple thrusters aligned so that the thrusters are offset vertically and horizontally relative to the centre of the vehicle.

[0008] The invention that is the subject of the application numbered “WO2011059197” in the state of the art relates to a remotely operated vehicle (ROV), and more specifically, to a remotely operated vehicle (ROV) based on an unmanned, underwater robot with multiple degrees of freedom, capable of providing a fixed remote control and accurate position control and maintaining posture.

[0009] The invention that is the subject of application numbered "CN108674616A” in the state of the art describes a method of rescuing an autonomous underwater vehicle. Said autonomous underwater vehicle consists of a pressure-resistant casing, a submarine earthquake wave detection module, and a multi-freedom propulsion module. After receiving the underwater sound return signals of the surface mother ship, the autonomous underwater vehicle takes off and floats upward to resist the suction force of the seabed soil.

[0010] In the state of the art, remotely operated vehicles (ROV) are included in the inspection class category. It is important to develop a vehicle with an air tank, a closed body with minimum water resistance forces, low-cost components working with high integration, and a single-channel rope (low cost) at the centre of the ROV, and allows to move more freely using powerline network adapters to switch Ethernet packets over the same power supply cable and that can manoeuvre freely at 6 DOF for communication between the off-vehicle control station and the vehicle (spaiser).

[0011] As a result, due to the negativities described above and the inadequacy of existing solutions on the subject, a new technology is needed in the relevant technical field. Brief Description and Aims of the Invention

[0012] The invention relates to a remotely operated unmanned underwater vehicle and communication system that can be controlled remotely in the underwater environment.

[0013] The invention focuses on developing a new 6 DOF inspection class ROV that overcomes the disadvantages of existing ROVs of the same category in both design and function. In the new design, a closed body with a small size and minimum resistance forces, and freely manoeuvrable at 6 DOF, low-cost components, low-cost single-channel rope with intelligent multiplexing of power lines and communication signal, and a system to be used with any PC instead of dedicated control station were taken into account.

[0014] The most important aim of the invention is to enable the vehicle to rotate freely around any axis with minimum effort and then to manoeuvre freely, since the centre of gravity point is accepted as the origin of the local coordinate frame of the vehicle.

[0015] Another aim of the invention is that the total density (including all components in the core) is equal to the density of water. This allows the vehicle to dive below the surface of the water with minimum effort.

[0016] Description of Figures

[0017] FIGURE 1 is the drawing showing the isometric view of the core of the invention.

[0018] FIGURE-2 is the drawing showing the isometric view of the core of the invention.

[0019] FIGURE-3 is the drawing showing the top view of the vehicle that is the subject of the invention.

[0020] FIGURE-4 is the drawing showing the isometric view of the vehicle that is the subject of the invention.

[0021] FIGURE-5 is the drawing showing the schematic view of the system that is the subject of the invention. Reference numbers

[0022] 100 Core

[0023] 110. sealing ring

[0024] 120. dome

[0025] 130. hole

[0026] 140. upper hole

[0027] 150. core body

[0028] 200 Outer casing

[0029] 300 Thruster

[0030] 400 Vertical thruster

[0031] 500 Application

[0032] 600 Microcontroller

[0033] 10 Inertial measurement unit

[0034] 20 Depth sensor

[0035] 30 Magnetometer

[0036] 40 Temperature sensor

[0037] 50 Leak sensor

[0038] 60 IP camera

[0039] Detailed Description of the Invention

[0040] The invention relates to a remotely operated unmanned underwater vehicle and communication system that can be controlled remotely in the underwater environment. The vehicle comprises the outer casing (200), core (100), microcontroller (600), inertial measurement unit (10), depth sensor (20), magnetometer (30), temperature sensor (40) and leak sensor (50).

[0041] The core (100) provides a dry room containing all electrical and electronic components. It is designed to be tough enough to withstand great depths of water. The core (100) comprises the core body (150), sealing ring (110), dome (120), hole (130) and upper hole (140).

[0042] The core body (150) and the sealing ring (110) are made of polyethylene with an average thickness of 10 mm, which allows the vehicle to withstand water pressure metres below the water surface. The core dome (120) is made of 8 mm thick transparent polyethylene material, resistant to water up to 300 meters, used as a transparent window for the IP camera (60) of the ROV. The sealing ring (110) and dome (120) are placed at the open end of the core body (150). The hole (130) contains 7 holes at the closed end of the core body (150), allowing the cables of the thrusters to pass. The upper hole (140) is located on the core body (150) and allows the control station cables to pass. The cables are insulated using PG11 waterproof brass glands with an IP68 rating, resistant to water pressure of up to 5 bars (approximately 50 metres).

[0043] The outer casing (200) is mainly used to assemble the core (100), thruster (300) and vertical thruster (400). The size of the vehicle is 680 x 580 x 180 mm. The outer casing (200) is not water resistant and consists of upper and lower covers produced using a 3 mm thick ABS layer with Thermoforming using an outer casing mould. The total density of the vehicle (including all components inside the core) is almost equal to the density of water. This allows the vehicle to dive below the surface of the water with minimum effort. The centre of gravity point is considered as the origin of the local coordinate frame of the vehicle. This makes it easy for the vehicle to rotate freely around any axis with minimal effort and then manoeuvre freely.

[0044] The vehicle cruises using 7 ETR100 type thrusters. The 7 thrusters are arranged as follows: These comprise three vertical thrusters (400), used primarily for vertical motion control and horizontal stability, and another four thrusters (300), used primarily for planer motion control, giving the vehicle six degrees of freedom (6DOF). The planner thrusters 300 are inclined at 22.5 degrees to allow 87% of the thrust component affecting forward-backward motion and 49% of the thrust component affecting left-right motion.

[0045] The electrical and electronic layer is divided into 2 parts: off-board, which is the control station, and on-board, which is the ROV itself. The maximum power ratings of the ETR100 thruster are approximately 192 Watts (12 VDC x 16 Amp.). The total power consumption for 7 thrusters is around 1350 Watts at most, and with an additional 150 Watts for other circuits and devices on the ship, the total power becomes 1500 Watts. Using a 12 VDC power supply requires a very thick cable as it will transfer approximately 125 Amps. For a better and more effective solution, a thinner cable can be used using a 50 VDC power supply, which will require approximately 30 Amps.

[0046] The microcontroller (600) enables the control of the vertical thruster (400) and the thruster (300). The microcontroller (600) communicates with the inertial measurement unit (10), depth sensor (20), magnetometer (30), temperature sensor (40), and leak sensor (50), and sends the sensor data to the application (500). The microcontroller (600) enables the IP camera (60) to be controlled with commands coming from the application (500). The microcontroller (600) provides a warning to the user via the application (500) when the value coming from the temperature sensor (40) is higher than the determined temperature value. The microcontroller (600) provides a warning to the user via the application (500) when the leak sensor (50) detects a leak.

[0047] The inertial measurement unit (10) has an accelerometer that measures linear acceleration signals in three axes and a gyroscope that can provide angular velocity signals in three axes in space. The inertial measurement unit (10) enables the calculation of the vehicle's orientation angles.

[0048] The depth sensor (20) measures the water pressure outside the outer casing (200) and calculates the depth accordingly.

[0049] The magnetometer (30) provides the navigation direction by measuring the intensity of the magnetic field. The temperature sensor (40) enables the detection of overheating within the core.

[0050] The leak sensor (50) enables detection of possible water ingress into the core.

[0051] The IP camera (60) enables images to be taken with its rotatable camera head and to be converted into digital data and transferred over the network. The IP camera (60) is transmitted directly to the control station via the network switch and then to the powerline network adapter. The rotatable camera head is controlled by the built-in microcontroller (600) according to the commands coming from the application (500).

[0052] For communication between the off-board control station and the vehicle, powerline network adapters are used to exchange Ethernet packets over the same power supply cable. This reduces the complexity of adding extra cables that could add more resistance to the movement of the vehicle.

[0053] The application (500) communicates with the microcontroller (600) to control the vehicle and displays vehicle sensor data and warnings through an interface. The application (500) comprises an interface that enables the management of the IP camera (60).

[0054] The new inspection class category Remotely Operated Vehicle (ROV) was developed to overcome the disadvantages of existing ROVs in the same category. In the new design, a system that is small, can manoeuvre freely at 6 DOF, has a closed body with minimum water resistance forces, low-cost components working with high integration, single-channel rope (low cost) and can be used with any PC instead of a special control station is taken into account.

[0055] In the invention, the detailed design of the internal network connecting the ROV's sensors, thruster controllers and camera is shown, and the intelligent communication architecture between the ROV and the control station is also demonstrated. Finally, the invention comprises many aspects at the computer layer, including the communication protocol between the control station and the ROV, the calculation of high-precision orientation angles using the Inertial Measurement Unit (IMU), the direction calculation of the ROV, and the GUI of the control station.

Claims

CLAIMS1. A remotely operated unmanned underwater vehicle and communication system that can be controlled remotely in the underwater environment, comprising:- the core (100) that comprises at least one core body (150) providing dry room for receiving electronic components from its open end; sealing ring (110) that allows the dome (120) to be mounted on the open end of the core body (150); at least one hole (130) at the closed end of the core body (150), allowing the cables of the thrusters to pass; at least one core dome (120) used as a transparent window for the IP camera (60); and at least one upper hole (140) located on the core body (150) allowing the control station cables to pass through,- at least one outer casing (200) that holds the core (100), thruster (300) and vertical thruster (400) together, and is covered with a waterproof bottom cover and top cover,- three vertical thrusters (400) providing vertical movement control and horizontal stability,- four thrusters (300), which give the vehicle six degrees of freedom and provide forward-backward and left-right movement control of the vehicle,- at least one microcontroller (600) that ensures controlling the vertical thruster (400) and thruster (300); sends the sensor data to the application (500) by communicating with the inertial measurement unit (10), depth sensor (20), magnetometer (30), temperature sensor (40), and leak sensor (50); controls the IP camera (60) with commands from the application (500); provides a warning to the user via the application (500) when the value coming from the temperature sensor (40) is higher than the determined temperature value; and provides a warning to the user via the application (500) when the leak sensor (50) detects a leak,- at least one inertial measurement unit (10), which has an accelerometer that measures linear acceleration signals in three axes and a gyroscope that can provide angular velocity signals in three axes in space, enabling the calculation of the vehicle's orientation angles,- at least one depth sensor (20) on the vehicle, which measures the water pressure outside the outer casing (200) and calculates the depth accordingly,- at least one magnetometer (30) on the vehicle, which enables to indicate the navigation direction by measuring the intensity of the magnetic field,- at least one temperature sensor (40) on the vehicle that detects the temperature within the core (100),- at least one leak sensor (50) on the vehicle that detects water ingress into the core (100),- at least one IP camera (60) on the vehicle, which enables taking images with a rotatable camera head and converting these images into digital data and transferring them over the network, and- an application (500) that runs on an electronic device, communicates with the microcontroller (600) for remote control of the vehicle, displays vehicle sensor data and warnings through an interface, and comprises an interface that allows the IP camera (60) to be managed.

2. A remote operated unmanned underwater vehicle and communication system according to Claim 1 , comprising core body (150) and sealing ring (110) made of polyethylene.

3. A remote operated unmanned underwater vehicle and communication system according to Claim 1 , comprising dome (120) made of transparent polyethylene material.

4. A remote operated unmanned underwater vehicle and communication system according to Claim 1 , comprising thruster (300) inclined at 22.5 degrees to allow 87% of the thrust component affecting forward-backward motion and 49% of the thrust component affecting left-right motion.

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