System for Controlling Forces Applied on a Hydrodynamic Body Adhered to and Moving Along a Hull of a Sailing Ship

This application claims the benefit of priority of U.S. Provisional Patent Application No. 63/635,672, filed Apr. 18, 2024, the contents of which are incorporated herein by reference in their entirety.

The present disclosure relates generally to systems and methods for controlling forces on a hydrodynamic body adhered to and moving along a hull of a ship during sailing.

A marine environment brings challenges that do not exist in a terrestrial environment. When it comes to a body which is adhered to a ship yet needs to move along the ship's hull during the sailing of the ship, the challenges are even bigger. A sailing ship is subject to the influence of many forces, starting with the waves and ending with underwater currents which constantly change. While adhering a static body to the ship's hull is possible, the allowance of movement along the ship's hull brings to slipping or detachment of the body from the hull due to lift and drag forces operating on the body. Adding additional forces operating on the moving body resulting from the underwater currents and the ship's speed, makes the allowance of movement of the body along the ship's hull very challenging. Overcoming the problem of detachment and/or slipping of the body from the ship's hull opens a door to efficient solutions for cleaning and inspecting ships and their related equipment.

One example for such an efficient solution may be a cleaning equipment for ships which deals with the Biofouling problem. Biofouling is the accumulation of microorganisms, plants, algae, or small animals where it is not wanted on surfaces such as ship and submarine hulls, devices such as water inlets, pipework, grates, ponds, and rivers that cause degradation to the primary purpose of said items. The problem of biofouling brings to an increased fuel consumption of ships and to time waste in port for cleaning the ship, as current cleaning methods require the ship to be stationary. In addition, small animals, plants and organisms accumulated on the ship due to biofouling may cause damage to natural environment in the port of destination of the ship, as being invasive species.

Therefore, providing a system and method which allows adhering a body to a ship's hull yet allowing movement of the body along the ship's hull, enables cleaning of the ship's hull during sailing of the ship, preventing biofouling creation, saving fuel consumption, and preventing time waste during porting for cleaning.

Thus, there is a need for a system and a method for controlling forces applied on a body adhered to a ship's hull, allowing movement along the hull during sailing, without detachment and/or sliding of the body from the ship's hull.

According to some embodiments, systems and methods for controlling forces applied on a hydrodynamic body adhered to and moving along a hull of a sailing ship, are presented.

According to some embodiments, there is provided a system for controlling forces applied on a hydrodynamic body adhered to and moving along a hull of a sailing ship by manipulating water currents around the body. According to some embodiments, the hydrodynamic body comprises at least two wheels, a first wheel in a first side of the hydrodynamic body controlled by a first motor and a second wheel in a second side of the hydrodynamic body controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship. According to some embodiments, the control of the forces applied on the hydrodynamic body is done by using mechanical fingers and dynamic wings which are located at the sides of the hydrodynamic body and which deploy and/or open in different directions and angles. Advantageously, according to some embodiments, the mechanical fingers cope with situations where momentary extreme forces operate on the hydrodynamic body and prevent the detachment of the hydrodynamic body from the ship's hull.

Advantageously, according to some embodiments, the dynamic wings provide a stability system to the hydrodynamic body, by changing the torque balance according to the opening angle of the dynamic wings.

Advantageously, according to some embodiments, the hydrodynamic design of the body provides an attachment force which attaches the body to the ship's hull, as long as the body is underwater during sailing. This force is proportional to the ship's speed and increases as the sailing speed increases.

According to some embodiments, one example for a hydrodynamic body in which the system presented herein is integrated may be a cleaning robot. In this case the cleaning robot is adhered to the ship's hull and the system presented herein, which is integrated into the cleaning robot allows the cleaning robot to move along the ship's hull and clean the hull even during sailing of the ship and even underwater without being detached from the ship's hull.

Advantageously, according to some embodiments, in this case, the system presented herein allows the cleaning robot to clean the ship during sailing, and thus providing a solution to the problem of biofouling by removing the biofouling at a very early stage.

According to an aspect of some embodiments, a system for controlling forces applied on a hydrodynamic body adhered to and moving along a hull of a sailing ship is presented. The hydrodynamic body comprises at least two wheels, a first wheel in a first side of the hydrodynamic body controlled by a first motor and a second wheel in a second side of the hydrodynamic body controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship. The system comprises:

According to some embodiments, the hydrodynamic body comprises a plurality of carts, each cart having one wheel in a first side controlled by a first motor and a second wheel in a second side controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship, and wherein the mechanical fingers are located in line with the length of the hydrodynamic body and/or on a downstream side of each of a wheelhouse of each cart, and/or on a top side of the cart, which is furthest from the ship's hull; and wherein the dynamic wing/s are located at each side of each cart of the hydrodynamic body.

According to some embodiments, the hydrodynamic body is adhered to the ship with magnets and with forces generated by a passive hydrodynamic design of the hydrodynamic body.

According to some embodiments, the hydrodynamic body is a robot.

According to some embodiments, the robot is a cleaning robot.

According to some embodiments, when the mechanical fingers are deployed, the trailing edge rises against the water current to position the mechanical fingers at an angle between 0 and 90 degrees.

According to some embodiments, the dynamic wing is opened by pivoting around the upstream end of the wing.

According to some embodiments, the system further comprises a plurality of additional mechanical fingers located along the hydrodynamic body and facing different directions, such that the moments of force acting on the plurality of carts are controlled by the controller to keep the hydrodynamic body stable.

According to some embodiments, the IMU sensor provides differences in the direction of the hydrodynamic body at a resolution of 0.001 deg.

According to some embodiments, the IMU sensor's sample rate is 400 samples/second.

According to some embodiments, the instructions from the controller to the mechanical fingers and dynamic wings contain more than one step, to stabilize the hydrodynamic body.

According to another aspect of some embodiments, a method for controlling forces applied on a hydrodynamic body adhere to and moving along a hull of a ship is presented. The hydrodynamic body comprises at least two wheels, a first wheel in a first side of the hydrodynamic body controlled by a first motor and a second wheel in a second side of the hydrodynamic body controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship, the method comprises the steps of:

According to some embodiments, the hydrodynamic body comprises a plurality of carts, each cart having one wheel in a first side controlled by a first motor and a second wheel in a second side controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship, and wherein the at least two mechanical fingers are located in line with the length of the hydrodynamic body and/or on a downstream side of each of a wheelhouse of each cart, and/or on a top side of the cart, which is furthest from the ship's hull, and wherein the dynamic wings are located at each side of each cart of the hydrodynamic body.

According to some embodiments, when the controller receives from the motor consumption sensor a signal that the motor consumption of electrical current is above a predetermined range, the controller instructs each mechanical finger to open and close at a fluttering movement at a certain frequency which creates a lift force such that the adhesion force is reduced and the friction on the relative wheel is reduced; and

Certain embodiments of the present disclosure may include some, all, or none of the above advantages. One or more other technical advantages may be readily apparent to those skilled in the art from the figures, descriptions, and claims included herein. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In case of conflict, the patent specification, including definitions, governs. As used herein, the indefinite articles “a” and “an” mean “at least one” or “one or more” unless the context clearly dictates otherwise.

The principles, uses, and implementations of the teachings herein may be better understood with reference to the accompanying description and figures. Upon perusal of the description and figures present herein, one skilled in the art will be able to implement the teachings herein without undue effort or experimentation. In the figures, same reference numerals refer to same parts throughout.

In the description and claims of the application, the words “include” and “have”, and forms thereof, are not limited to members in a list with which the words may be associated.

As used herein, the term “about” may be used to specify a value of a quantity or parameter (e.g. the length of an element) to within a continuous range of values in the vicinity of (and including) a given (stated) value. According to some embodiments, “about” may specify the value of a parameter to be between 80% and 120% of the given value. For example, the statement “the length of the element is equal to about 1 m” is equivalent to the statement “the length of the element is between 0.8 m and 1.2 m”. According to some embodiments, “about” may specify the value of a parameter to be between 90% and 110% of the given value. According to some embodiments, “about” may specify the value of a parameter to be between 95% and 105% of the given value.

As used herein, according to some embodiments, the terms “substantially” and “about” may be interchangeable.

According to some embodiments, there is provided a system and method for controlling forces on a hydrodynamic body adhered to and moving along a hull of a sailing ship, by manipulating water currents around the hydrodynamic body.

As used herein, according to some embodiments, in the description and claims the term “mechanical finger/s” relates to a wing-shaped mechanism with a leading edge and a trailing edge, which opens perpendicular to the water current. As used herein the term “mechanical finger/s” and “finger/s” may be interchangeable.

As used herein, according to some embodiments, in the description and claims the term “dynamic wing/s” relates to a wing-shaped mechanism with a converging profile, which is located in parallel to the hydrodynamic body and which opens in parallel to the ship's hull as will be further described below.

schematically shows a block diagram of a systemfor controlling forces on a hydrodynamic body adhered to and moving along a hull of a sailing ship, according to some embodiments. According to some embodiments, the hydrodynamic body comprises at least two wheels, a first wheel in a first side of the hydrodynamic body controlled by a first motor and a second wheel in a second side of the hydrodynamic body controlled by a second motor, enabling the hydrodynamic body to move along the hull of the ship. According to some embodiments, the wheels may be a caterpillar tread or any other conveyance/movement mechanism.

According to some embodiments, the hydrodynamic body may be adhered to the ship's hull with magnets, which keep the hydrodynamic body attached to the ship's hull yet allow movement of the hydrodynamic body. In addition, the hydrodynamic design of the body also contributes to the adhesion of the hydrodynamic body to the ship's hull by creating an attachment force which attaches the body to the ship's hull, as long as the body is underwater during sailing, resulting from the hydrodynamic design. This force is proportional to the ship's speed and increases as the sailing speed increases.

According to some embodiments, systemincludes an array of sensors, a controller, at least two mechanical fingers, and at least two dynamic wings. According to some embodiments, systemcontrols the forces on a hydrodynamic body which is adhered to and moving along a hull of a sailing ship, by manipulating water currents around the hydrodynamic body, using the at least two mechanical fingers and the at least two dynamic wings. According to some embodiments, array of sensorsindicates the state of the hydrodynamic body to controllerand provides information regarding the environmental changes and especially changes in the forces applied to the hydrodynamic body. Controllermonitors the hydrodynamic body's adhesion status and controls the state of the mechanical fingers and dynamic wings. Controllerin response to the information received from array of sensor, analyzes the information and instructs each mechanical fingerand each dynamic wingto open to a desired position in order to increase or reduce adhesion of the hydrodynamic body to the ship, thereby optimizing the adhesion and stability of the hydrodynamic body. According to some embodiments, controllermay be or may include a computer, a processing unit or a processing circuitry or the like.

According to some embodiments, array of sensorsincludes an Inertial Measurement Unit (IMU) which senses the acceleration of the hydrodynamic body, therefore relevant forces on the hydrodynamic can be derived.

According to some embodiments, array of sensorincludes a motor consumption feedback sensor, which provides a signal regarding the consumption of electrical current of the motor that controls the wheel, to controller. According to some embodiments, each motor has its own motor consumption feedback sensor. According to some embodiments, when controllerreceives from the motor consumption sensor a signal that the motor consumption of electrical current is above a first predetermined range, controlleris configured to instruct each mechanical finger to open and close at a fluttering movement at a certain frequency which creates a lift force such that the adhesion force is reduced and the friction on the relative wheel is reduced. According to some embodiments, when controllerreceives from the motor consumption sensor a signal that the motor consumption of electrical current is below a second predetermined range, controlleris configured to instruct each or the relevant mechanical finger and/or dynamic wing to open in an angle creating a down force such that the adhesion force is increased and the friction on the relative wheel is increased to eliminate slipping and disconnection of the hydrodynamic body from the ship. According to some embodiments the first and second predetermined thresholds may be the same threshold, however, according to some other embodiments the first and second threshold are different and there is a gap between the first and second thresholds wherein when the motor consumption sensor indicates the electrical consumption of the motor is in said gap, no action is taken.

According to some embodiments, at least two mechanical fingersare a wing-shaped mechanism with a leading edge and a trailing edge. When mechanical fingersare deployed, the trailing edge rises against the water current to position mechanical fingersin any angle between 0 and 90 degrees. According to some embodiments, the angle is determined by controller, which is configured to decide whether the hydrodynamic body needs to be adhered to the ship's hull with an additional force or if the hydrodynamic body is stable, but the stress on the motors is too high. According to some embodiments, the positioning of mechanical fingersin an angle between 0 and 90 degrees creates a force perpendicular to the ship's hull which affects the adhesion of the hydrodynamic body to the ship, thereby preventing detachment of the hydrodynamic body from the ship. According to some embodiments, mechanical fingersmay also open and close at a fluttering movement at a certain frequency to create a lift force which reduces stress on the motors and which reduces adhesion of the hydrodynamic body to the ship.

According to some embodiments, systemmay be integrated in any hydrodynamic body, which is adhered to a hull of a ship, yet moving along the hull of the ship, including during sailing. According to some embodiments the hydrodynamic body may include one cart or a plurality of carts, which are connected to each other with a flexible joint, allowing movement of the hydrodynamic body.

schematically shows a hydrodynamic body, which is adhered to and moving along a hull of a sailing ship, into which systemis integrated, according to some embodiments. Hydrodynamic bodyincludes, according to some embodiments, four carts,,,, and is adhered to the ship's hull with magnets (not shown). Each cart includes two wheels (not shown) which are covered with wheelhouses, one on each side of the cart, such that cartincludes wheelhousesand′, cartincludes wheelhousesand′, cartincludes wheelhousesand′ and cartincludes wheelhousesand′. According to some embodiments, each wheel is controlled by a separate motor (not shown), thus enabling hydrodynamic bodyto move along the hull of the ship. According to some embodiments, mechanical fingers,′,,′,,′,and′ have a wing shape with a leading edge and a trailing edge and are located on the downstream side of each of wheelhouses,′,,′,,′,and′ respectively, of each cart. According to some embodiments, additional mechanical fingers such as mechanical fingers,,,,,,,,,,,may be located on a top side of the cart, which is furthest from the ship's hull. According to some embodiments, a plurality of additional mechanical fingers may be located along the hydrodynamic body and facing different directions, such that the moments of force acting on each one of carts,,,, are controlled by a controller such as controllerto keep the hydrodynamic body stable and attached to the ship.

According to some embodiments, mechanical fingers,′,,′,,′,and′ are set in line with the length of hydrodynamic body. When the mechanical fingers are deployed, the trailing edge rises against the water current to position each of mechanical fingers,′,,′,,′,and′ at an angle creating either a adhesion force, which is a force perpendicular to the ship's hull, which attaches the hydrodynamic body to the ship, thus preventing detachment of hydrodynamic bodyfrom the ship, or creating a lift force reducing adhesion of hydrodynamic bodyto the ship. According to some embodiments, mechanical fingers,′,,′,,′,and′ operate (open and close) at a fluttering movement at a certain frequency, which disturbs the flow on the top side of hydrodynamic bodyand changes the pressure field, such that the lift force is created.

According to some embodiments, when mechanical fingers,′,,′,,′,and′ are deployed, the trailing edge rises perpendicular to the water current to position mechanical fingerin any angle between 0 and 90 degrees, creating a force perpendicular to the ship's hull which affects the adhesion of hydrodynamic bodyto the ship, thereby preventing detachment of hydrodynamic bodyfrom the ship. According to some embodiments, in other cases, where hydrodynamic bodyis well adhered to the ship's hull and the stress on the motors of the wheels is above a predetermined threshold—the trailing edge rises perpendicular to the water current, and then lowers perpendicular to the water current at a fluttering movement at a certain frequency that a lift force is created, which reduces adhesion of hydrodynamic bodyto the ship, thus reducing the stress on the motors.

Init can be seen that mechanical fingers′ andare open to an angle of about 30 degrees, and mechanical fingers,′,,,′ and′ are closed (i.e. open to 0 degrees).

schematically shows the direction of the adhesion force created by the deployment of mechanical finger, according to some embodiments.

Wheelhouse areaof wheelhouseseen inis an area with a rounded curvature. Mechanical fingeris located on a downstream side of wheelhouseand opens perpendicular to the water current. Mechanical fingermay be open in any angle between 0 and 90 degrees. By locating mechanical fingeron the downstream side of wheelhousethe water current which tends to accelerate in areaof the rounded part of wheelhouseis blocked and routed upward by mechanical finger. The redirection of current leads to a transfer of momentum between the water and the upper part of the wing(a), following Newton's third law. Due to the angle of mechanical fingerthe transfer of momentum turns into an adhesion force F. In parallel, slotbetween mechanical fingerand wheelhouseincreases the acceleration of water current to the bottom part(b) of mechanical finger, which creates a low pressure on the rear part of mechanical finger, according to Bernoulli's law, thus creating a positive pressure differential between the top part(a) and bottom part(b) of mechanical finger, resulting in a lift force. As a result of the water current cutoff by mechanical finger, turbulence is created under/behind(b) mechanical finger, in area.

The turbulence decreases the pressure behind mechanical finger. The water current on the external side of wheelhouseaccelerates also to the rear part of mechanical fingerand contributes to the decrease of pressure behind mechanical finger. The shape of mechanical finger, which is as a wing profile with a rounded leading edge and a pointed trailing edge enables the Coanda effect to exist and an optimal flow over mechanical finger. Due to the pressure differences between the upward part and the downward part of mechanical finger, an attachment force is created on mechanical finger, which adheres wheelhouseto the ship.

According to some embodiments, a plurality of additional mechanical fingers such as mechanical fingers,,,,,,,,,,,may be located along the hydrodynamic body and facing different directions, such that the forces and their associated moments acting on the plurality of carts are controlled by the controller to keep the hydrodynamic body stable and attached to the ship's hull.