The invention provides a light guide element comprising a light guide and a layer element, wherein the light guide comprises a light guide face and wherein the layer element comprises an optical layer, wherein said optical layer is in contact with at least part of the light guide face, wherein the optical layer has a first index of refraction (n1) smaller than the refractive index of seawater, wherein the light guide comprises a UV radiation transmissive light guide material.

A system provides impressed current cathodic protection (ICCP) of a marine structure (50) and powers a load in a load arrangement (100) arranged on the marine structure (50) and in contact with the water (10). The power source provides a supply current to generate an electrical potential of the marine structure. The load arrangement (100) has an electrode arranged (130) to extend from the load arrangement into the water for transferring the supply current via the water. The load (20) is coupled between the electrode (130) and a power node (120). The power source is connected to the marine structure and to the power node. The load arrangement is arranged to use the supply current to provide power to the load. Thereto the supply voltage may have an AC component at a high frequency. The load may be an UV-C LED for emitting anti-fouling light.

A system provides impressed current cathodic protection (ICCP) of a marine structure (50) and powers a load in a load arrangement (100) arranged on the marine structure (50) and in contact with the water (10). The power source provides a supply current to generate an electrical potential of the marine structure. The load arrangement (100) has an electrode arranged (130) to extend from the load arrangement into the water for transferring the supply current via the water. The load (20) is coupled between the electrode (130) and a power node (120). The power source is connected to the marine structure and to the power node. The load arrangement is arranged to use the supply current to provide power to the load. Thereto the supply voltage may have an AC component at a high frequency. The load may be an UV-C LED for emitting anti-fouling light.

The method and system uses ultrasound (US) transducers in contact with an inboard surface underwater portions of marine vessels or structures. By first digitally generating disruptive, multi-frequency, interfering US waveform signals (complex waveforms, typically replicating a Bessel function) and then converting the signals into analog, the transducers generate disruptive, multi-frequency, interfering US waveforms through the underwater portions of the marine vessels and structures which waveforms disrupt unwanted marine growth on the water-side of the vessel or structure. The digital signals, and also the analog signals, are complex waveform signals, typically produced with a Bessel function. The US transducers are either circular membrane transducers or surface transducers. A computer processor coupled to a memory, generates the complex waveform signals fed to the US transducers.

The method and system uses ultrasound (US) transducers in contact with an inboard surface underwater portions of marine vessels or structures. By first digitally generating disruptive, multi-frequency, interfering US waveform signals (complex waveforms, typically replicating a Bessel function) and then converting the signals into analog, the transducers generate disruptive, multi-frequency, interfering US waveforms through the underwater portions of the marine vessels and structures which waveforms disrupt unwanted marine growth on the water-side of the vessel or structure. The digital signals, and also the analog signals, are complex waveform signals, typically produced with a Bessel function. The US transducers are either circular membrane transducers or surface transducers. A computer processor coupled to a memory, generates the complex waveform signals fed to the US transducers.

In one embodiment, there is disclosed a robot configured to clean a surface of a coating having a König pendulum hardness of less than 75 counts, the robot comprising: a cleaning brush assembly comprising a lamellar cleaning brush having a plurality of lamellas extending outwardly from a brush core and having a height, the lamellar cleaning brush arranged to rotate about its axis to apply a cleaning action to the surface when it is in contact with the surface; wherein the robot is configured to apply a degree of compression of the brush on the surface such that the brush is held in a position a distance, towards the surface of the coating, away from an initial position at which the brush is in contact with, but not deformed by, the surface of the coating, wherein said distance is less than 56% of the height of the plurality of lamellas.

A rotating grooming brush comprising a brush hub having grooming elements and shroud elements, and method for grooming a surface having an unwanted material thereon. The elements extend from the brush hub and may be positioned near its outer periphery. The elements may be grooming elements forming an array and shroud elements forming a shroud array. A rigid or elastomeric shroud extending from the brush hub surface may optionally be included about the edge of the brush hub, to the outside of the grooming elements. Rotation of the grooming attachment brush causes a low pressure region to build in the central area of the brush. This low pressure region creates a resulting force that forcefully attracts the grooming attachment brush to the surface to be groomed. The resulting force is controlled by the diameter of the brush hub, arrangement, of the elements and the speed of rotation.

A rotating grooming brush comprising a brush hub having grooming elements and shroud elements, and method for grooming a surface having an unwanted material thereon. The elements extend from the brush hub and may be positioned near its outer periphery. The elements may be grooming elements forming an array and shroud elements forming a shroud array. A rigid or elastomeric shroud extending from the brush hub surface may optionally be included about the edge of the brush hub, to the outside of the grooming elements. Rotation of the grooming attachment brush causes a low pressure region to build in the central area of the brush. This low pressure region creates a resulting force that forcefully attracts the grooming attachment brush to the surface to be groomed. The resulting force is controlled by the diameter of the brush hub, arrangement, of the elements and the speed of rotation.

An autonomous ship bottom inspection method by a ROV(s) based on a ship 3D model in STL format is provided. The ship 3D model is obtained and a surface thereof is spliced by triangular facets. Body 3D coordinate points of the ship 3D model are obtained and then expanded according to a safety distance of ROV and ship to obtain inspection track points of the ROV. The ship 3D model is divided into regions, and the inspection track points in each region are performed with interpolation and smoothing. Smoothed inspection track points of the regions are connected as per a result of the dividing to obtain a ship bottom inspection track, a real-time position of the ROV is obtained, a ship bottom inspection path is generated based on the ship bottom inspection track and the real-time position. The ROV is controlled to move as per the ship bottom inspection path.

A system for cleaning a structure arranged in a body of water. The system includes: a vehicle operable to move through the water and clean the structure; a tether connectable between the vehicle and a fixed position; a deployment mechanism securable relative to the structure and configured to move the vehicle into, and out of, the water; and a processing unit configured to communicate with the vehicle and the deployment mechanism. The processing unit is configured to execute a repeating cleaning schedule to cause the deployment mechanism to operate to move the vehicle into the water, the vehicle to operate to clean at least a portion of the structure, and the mechanism to operate to remove the vehicle from the water.