WO2014023925A1

WO2014023925A1 - Survey apparatus and methods for collecting sensor data in a body of water

Info

Publication number: WO2014023925A1
Application number: PCT/GB2013/000329
Authority: WO
Inventors: David RIGG; Luke MURRAY
Original assignee: North Sea Systems Limited
Priority date: 2012-08-05
Filing date: 2013-08-05
Publication date: 2014-02-13
Also published as: GB201402895D0; GB2509256A; GB2504685A; GB2509256B; GB201213895D0

Abstract

Survey apparatus (17) and methods for collecting sensor data in a body of water are disclosed. A buoy (4) comprises a first sensor means (11) and a transmitter (12) for transmitting collected sensor data to a receiver. A mooring (14) for the buoy, has a second sensor means (13). An umbilical (2) is used for connecting the buoy to the mooring, and for receiving collected sensor data from the second sensor. The survey apparatus (17) is adapted to collecting environmental data in harsh environmental conditions, the purpose built buoy (4) designed for operation in extreme wave and tidal flow conditions. The system (7) for providing power is contained within the buoy (4) to provide continuous power to on board sensors (11) and telemetry (12) to enable operation for extended periods of time without intervention. A radio transmitter (12) is provided to allow communication to a system located onshore. The umbilical (2) comprises a structural member and electrical cabling, wherein the structural member forms the tether (2) connecting the buoy (4) to the mooring (14) and the cabling (16) provides communication and power to bottom mounted sensors (13). A mooring (14) is provided that is installed on the seabed that keeps station for the system in the extreme conditions.

Description

SURVEY APPARATUS AND METHODS FOR COLLECTING SENSOR DATA

IN A BODY OF WATER

Field of the Invention

The present invention relates generally to a system facilitating environmental survey in bodies of water, for example in extreme conditions such as high tidal flow and large waves.

Background of the Invention As the growing marine energy industry starts to take shape there is an increasing requirement to be able to deploy sensors to capture detailed environmental information for extended periods of time.

Developers need accurate data describing, but not limited to, flow velocities, turbulence, flow velocity variation with depth, and wave height. Turbulence and wave parameters for a given site are particularly important because these effects can have a detrimental impact upon the fatigue life of structures and therefore they must be adequately designed for. The highly dynamic nature of most marine energy sites makes it particularly difficult to take precise measurements. It also makes the deployment and recovery of survey instrumentation hazardous. Without live feedback of the data being collected and no indication of the correct deployment of the sensor, many sensors are being deployed in these environments unsuccessfully. The failure to capture the required data is only discovered after retrieval of the sensor and post analysis of the data. This results in large delays and significant wasted cost.

Without long term precise measurement of key environmental parameters for a given site, designers are forced to account for uncertainty in environmental conditions by applying safety factors to their designs. This drives up the size and costs of structures to be deployed in these environments.

Prior Art

For example, UK patent application number GB-A1 328 470 (Hagenuk Neufeldt Kuhnke GmbH) discloses a subaqueous oceanographical mast anchored by sinkers, the mast comprising a plurality of sections connected by universal joints provided with locking devices to lock each joint and form a rigid mast when the sections are placed in water.

Each section of the oceanographical mast has an instrument package e.g. for recording current, temperature, conductivity and sound velocity, the data being fed by an electric cable to a marker buoy containing recording equipment and a power supply.

This system, in common with other prior systems, has no means (in the marker buoy) for live feedback of the collected data. In addition, the system is unable to take measurements at specific and important sites, such as the ocean surface, at specific water depths or on the seabed/ocean floor.

Published International patent application WO-A-03/062044 (Main) discloses an apparatus for monitoring underwater conditions at an offshore location, including anchoring a sensing apparatus at the location, and transmitting information produced by the sensing apparatus to a receiver.

A disadvantage of the aforementioned apparatus for monitoring underwater conditions has been its ability to cope with high tidal flows and extreme wave environments often encountered in the winter. Furthermore in published International patent application WO-A-03/062044 there is no mention of profiled buoys or low drag moorings. Another disadvantage is that this system is also unable to take measurements at the ocean floor, and is unable to communicate with any device at the ocean floor.

It is an object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages, or to provide a useful alternative.

Summary of the Invention According to a first aspect of the present invention there is provided a survey apparatus for collecting sensor data in a body of water, the apparatus comprising: a buoy, including a first sensor means and a transmitter for transmitting collected sensor data to a receiver; a mooring for the buoy, including a second sensor means; and an umbilical for connecting the buoy to the mooring, and a means for transmission of collected sensor data from the second sensor means to the buoy.

This apparatus allows a means for collecting measurements on the body of water at the floor of the body of water via the mooring, so that measurements can be made available for both the surface and the floor.

Another aspect of the system is that it has been designed with a view to survive extreme environmental conditions of weather, tides and waves. For example, the 4 sealed compartments ensure that any leak is contained, allowing the system to survive until intervention can be arranged. The system would also incorporate condition monitoring to provide feedback on water ingress, structural loading and battery condition.

It is appreciated that the means for transmission of collected sensor data from the second sensor means to the buoy may^'also include a receiver for receiving data, control signals or commands. The data may include software or data to reconfigure certain devices or sensors. Signals may be transmitted to remote personnel, to a vessel, to a land based receiving station or to an earth orbiting satellite. In an embodiment, the buoy comprises a power system, and the umbilical is adapted to provide power from the power system to the second sensor means. This in addition allows a means for powering and communicating with a device on the floor of the body of water. Optionally a hydrofoil or wing may be deployed on the apparatus in order to act as a part of an intelligent mooring system. The hydrofoil, which may be arranged to retract into the survey apparatus, acts in a similar manner to a wing and generates lift. This arrangement may be employed to counteract the effect of the mooring and so lift the mooring. As a consequence the buoy and mooring system may be remotely 'flown' around a tidal site, at desired times when tides and currents favour this, so as to enable measurements to be taken from different locations using a single survey system and without intervention from a surface vessel. Preferably, the second sensor means is bottom-mounted on the mooring. More preferably, at least a portion of the second sensor means is mounted on a surface of the mooring for facing a floor of the body of water. Still more preferably, at least a portion of the second sensor means is configured to contact the floor of the body of water.

The sensor may face in any direction. However, ideally acoustic Doppler current profilers (ADCPs) need to face upwards and sonar sensors face outwards. Cameras for benthic measurements are ideally oriented to face downwards. For example, where the body of water is an ocean, the second sensor means can be arranged on the sea floor, after deployment of the mooring. Suitably, the buoy comprises one of: a monohull; a catamaran; and a small- waterplane-area twin hull. In an embodiment, the power system comprises an energy storage means. Preferably, the energy storage means is rechargeable, and the buoy comprises: a power generation means for recharging the energy storage means.

A radio link to a vessel provides marine operators with vital environmental data to help in the planning and execution of marine operations. This is particularly important for instances where liquidated damages are incurred due to weather related delays.

Suitably, the umbilical comprises structural outer members connected to the buoy and to the mooring.

In an embodiment, the umbilical comprises a plurality of inner cable cores for transferring power and/or transmitting data. Suitably, the first and/or second sensor means comprises an imaging device.

In an embodiment, the buoy further comprises a receiver for receiving remote control signals from a user device. For example, the user device may instruct the collection of data from one of the sensors at a particular time, or deploy a particular sensor.

In one embodiment, the apparatus comprises a plurality of buoys and respective moorings, one of which buoys being a master buoy, wherein each of the other of the plurality of buoys is adapted to transmit data to the master buoy. Suitably, the mooring comprises a member deployable to vary a holding power of the mooring. The member may be deployable remotely, controlled by the user device. Preferably, the deployable member is a hydrofoil. In an embodiment, the mooring further comprises a sampling device for obtaining a sample of the floor of the body of water.

One embodiment of a second aspect of the invention can provide a buoy for a survey apparatus according to any of the above embodiments, the buoy comprising a sensor means and a transmitter for transmitting collected sensor data to a receiver.

One embodiment of a third aspect of the invention can provide a mooring for a survey apparatus according to any of the above embodiments, the mooring comprising a sensor means.

One embodiment of a fourth aspect of the invention can provide a method of installing a survey apparatus according to any of the above embodiments, the method comprising: connecting an umbilical to the mooring and to the buoy; deploying the mooring on a floor of the body of water; and deploying the buoy on a surface of the body of water.

One embodiment of a fifth aspect of the invention can provide a method of collecting sensor data in a body of water, comprising the steps of: obtaining first sensor data from a buoy comprising a first sensor means; using an umbilical connecting the buoy to a mooring, the mooring having a second sensor means, to receive second sensor data from the second sensor means; and transmitting the collected first and second sensor data to a receiver.

One embodiment of another aspect of the present invention can provide a survey apparatus adapted to collecting environmental data in harsh environmental conditions, the apparatus comprising: a purpose built buoy designed for operation in extreme wave and tidal flow conditions; a power system contained with the buoy to provide continuous power to navigational aids, environmental sensors and telemetry to collect data for extended periods of time without intervention; a radio transmitter to allow collected data to be sent to a receiver station positioned onshore; an umbilical providing the tether connecting the buoy to a mooring and to provide a means of providing power to, and receiving transmission of data from, bottom mounted sensors deployed on the mooring; and a mooring that keeps station in the extreme conditions preventing the buoy from moving from its intended location.

A subsea platform for the secure and stable mounting of various telemetry and sensors may be provided In a preferred embodiment, the purpose built buoy will be comprised of a monohull floating arrangement. Alternatively, the buoy comprises a catamaran or small-waterplane-area twin hull (floating) arrangement.

Preferably, the buoy is sized to contain sufficient on board power in the form or energy storage such as batteries to power any navigational aids, environmental sensors and radio transmission to allow the survey to be performed without intervention for a period of up to several months.

Optionally, the buoy will contain on board power generation to enable recharging of the energy storage system contained within the buoy to facilitate longer deployments without intervention.

For example, the survey apparatus may further comprise an on board generation unit harnessing the power of the sun, tidal currents or wave to recharge the on board energy storage system in an effort to extend the intervention free operation of the system. The survey apparatus may comprise sensors used for the collection of environmental data. The sensors may be located on the sea floor on the mooring unit with data being transmitted to the buoy by means of the umbilical. The apparatus may further comprise a radio transmitter to provide real time communication of data collected to a shore based receiver station and to provide remote control of the survey system from shore.

In a preferred embodiment, the umbilical will be made from structural outer members sized to resist the substantial forces required to tether the buoy to the mooring. These outer structural members will be connected to the attachment point on the buoy and likewise to the mooring point on the bottom mounted mooring. Further preferably, the umbilical will provide a sufficient number of inner cable cores to provide power to the sensors mounted below the water on the mooring base from the on board power system located in the buoy, whilst also transmitting data collected from the sensors on the mooring to the buoy. In a preferred embodiment the mooring intended to be deployed on the seabed will provide mounting locations for environmental sensors to be mounted in their optimal mounting orientations.

The above aspects and embodiments may be combined to provide further aspects and embodiments of the invention.

It is to be appreciated that although reference has been made to a system for facilitating surveying bodies of water, the system may be used to provide a data link to a subsea power generation device. This could be as a backup to a shore cable or, in the case of a system that is prototypal and not connected to shore, it could be the only means of communicating with such a device. In an alternative configuration, load cells may be included in a mooring line in order to provide mooring load information, which can optionally be calibrated against flow and tide data. This information can be used in the design of moorings.

Brief Description of the Drawings

Preferred embodiments of the invention will now be described by way of specific example with reference to the drawings, in which:

Fig. 1 depicts a survey system intended for collecting environmental data in extreme conditions, according to an embodiment of the invention; Fig. 2 depicts a mono hull floating buoy design according to an embodiment of the invention; and

Fig. 3 depicts a plan view of the mooring which is mounted on the seabed, according to an embodiment of the invention.

Detailed Description of Preferred Embodiments of the Invention

Embodiments of the invention provide a system for taking detailed measurements of the environment in a body of water, such as an ocean, lake, river, artificial water storage facility or the like. These systems can provide means for taking measurements both at the surface and at the bottom of the body of water, and innovative ways of powering and communicating with a means for collecting the measurements on the floor of the body of water. In embodiments below, the example of a sea or ocean is taken as the body of water to illustrate the embodiments. Fig.1 depicts survey apparatus 17 according to an embodiment, adapted to collecting environmental data in harsh environmental conditions. The purpose built buoy 1 is hydrodynamically designed, shaped so that it is designed to perform well in extreme wave and tidal flow conditions. The buoy 1 is specifically designed to reduce drag acting on the structure and to be stable during high wave events.

For example, the hull of the buoy may be a monohull floating arrangement, or the buoy may be a catamaran or small-waterplane-area twin hull floating arrangement. In the example of a monohull arrangement, the buoy is designed so that the tip of the monohull can be arranged in the direction of the prevailing current or flow, so that the hull cuts through the flow or waves. The buoy is designed to withstand 5 m/s tidal flows and wave heights of 9 metres. The buoy may employ drag reducing coatings, a keel containing ballast, a rudder element to position the hull, and may be made narrow in comparison to the length of the buoy. The relative length and width may be in the ratio of at least 5:1 , preferably 7:1 and most preferably 10:1.

These features increase the stability and drag resistance of the buoy, greatly reducing mooring requirements.

The buoy may also be marked with any of a number of identifying marks, structures or devices, and may be lit to attract attention. For example, the marking and lighting may be made to conform to IALA standards, reducing risk and consent requirements.

The buoy can be constructed using a ballast frame, using marine grade aluminium. The buoy can be arranged so that a centre of gravity is positioned near a single lift point or attachment, so that a single lifting point and manoeuvre can deploy the buoy. The umbilical 2 provides the tether connecting the buoy 1 to a mooring 3 and provides a means of providing power to, and receiving transmission of data from, sensors 13 deployed on the mooring 3. As noted above, the umbilical can be made from structural outer members sized to resist the substantial forces required to tether the buoy to the mooring. These outer structural members can be connected to the attachment point on the buoy and likewise to the mooring point on the bottom mounted mooring. Such structural members may be known to the art. The structural members may be comprised of a set of interlocked sheath sections, enclosing the umbilical. The structural members may provide the majority of the tethering strength needed to secure the buoy to the mooring.

The umbilical can provide a sufficient number of inner cable cores to transfer power between the buoy and the mooring, for example to power the sensors mounted below the water on the mooring base, whilst also transmitting data between the buoy and the mooring. The inner cable cores may be woven or wound, to provide extra strength and protection. The umbilical may be winch adjustable to enable remote positioning of the buoy, for example in highly tidal areas the length of the umbilical may require frequent adjustment. A winch may be incorporated in one or both of the buoy and the mooring. On the mooring, the winch may be powered locally, or by the power transfer from the umbilical, and receive instructions to reel via the umbilical. At the buoy, the winch may be powered by the energy storage device, and actuated by a local motor.

The mooring 3 keeps station in the extreme conditions which prevents the buoy 1 from moving from its intended location. In one embodiment it does this by having sufficient mass to resist the drag acting on the buoy 1 as well as the mooring 3 itself. The mooring 3 like the buoy 1 , is specifically designed for reduced drag. In the embodiment shown, the mooring takes a trapezoidal shape, so that sides of the mooring slope up from a wider base to a smaller and/or narrower upper surface. This arrangement helps to reduce drag, allowing the mooring to maintain station even in extreme conditions. Alternatively, the mooring may take a sectioned cylinder shape, with a rounded upper surface. The mooring may incorporate devices to fix the mooring more securely to the sea bed, for example a hooking or stockless anchor mechanism or the like. Depicted in Fig. 2 is a monohull floating buoy 4 according to one embodiment, on which is housed a navigation mast 5 and a navigation aid 6 in the form of a light. The navigation aid 6 is powered via cables 8 from an energy storage device 7 which is mounted within a sealed chamber formed within the hull of the buoy 4. In addition to this a radio transmitter 12 is powered from the same energy storage device 7 to allow transmission of all collected data from on board sensors 11 and bottom mounted sensors 13 to a shore based or water-borne vessel based receiving station.

The transmitter and any power or support system can be made sufficiently powerful to provide real-time communication of collected data to the shore station. The transmitter may transmit data as soon as any is collected from any of the sensors available on the buoy or mooring, or may buffer the data slightly, or may collect portions of data for batch transmission. The transmission system may be adapted to provide different types of data transmission; for example the buoy may be provided with different types of transceiver (e.g. radio, microwave or other) to send/receive different types of transmission. The transmission type may be chosen by the sensor data type being collected, or may be instructed by signal received by the transceiver, for example from the shore station. The transmitter, transmission system and or processor may be adapted to compress data before transmission. The buoy's transmitter system also comprises a receiver, to obtain instructions from another device, such as another buoy or the shore station, and a processor to process the instructions and instigate any action. For example, the shore station may transmit instructions to the buoy via a radio signal to change a deployment angle, and the processor may instruct a motor powering a rudder device to re-orientate the buoy. The instructions received may be instructions to reel in/out the winch using the local motor, or to instruct the mooring winch. The instructions may prompt the processor to (de)activate one or more of the sensors on board the buoy, or to activate them in a particular way (for example, to position an imaging device in a particular orientation). The received signal may instruct the deployment of the member on the mooring which can alter the holding power of the mooring (see below).

The buoy may also be in data communication contact with other water-borne devices, such as marine energy devices, shipping and other vessels, and the like. In the case of a marine energy device, the sensors on the buoy may for example measure a tidal flow, and instruct the energy device to be (de)activated on the basis of the flow measured.

The buoy may in fact be one of a series of buoys deployed in an array, to collect multiple data points and/or types. The transceivers of the buoys can then be used to collect all data to one of the buoys, a master or central command buoy, so that the master buoy can relay all the data to the shore station, in one embodiment having pre-processed the data to do some initial collation of the data from the array.

The sensors 11 on board the buoy can be of any number necessary for collecting the relevant data, subject to the weight capacity of the buoy and the power capacity of the power system. The sensors can be of any type necessary for the desired data collection, for example they may include (not exclusively) optical or acoustic detectors, wave, wind and pressure sensors, water velocity sensors, sensors measuring the load transmitted between the mooring and the buoy on the tether, chemical detectors, imaging devices, and the like.

The sensors may be mounted wherever on the buoy is needed to perform the function: for example, wind sensors may be prominent on the deck of the buoy, whereas chemical detectors may be submerged. The sensors may be used, for example to assess sediment transportation, water quality, turbulence, noise measurements, measuring presence of particular types of marine life, benthic measurements, atmospheric pressure, water velocity profiles providing data as to what is occurring in the bulk of water at various depths, profiles

Acoustic Doppler current profilers (ADCPS) are used to record water velocity profiles. A turbine may provide a reading of water velocity at the position of the turbine. For example use of a turbine, in one embodiment, may be the same turbine used to generate tidal flow power for the buoy, and obtain video and still images, and the like. Specific types of sensors which may be included in the survey apparatus for collecting sensor data in a body of water, are:

- acoustic Doppler current profiler (ADCP) - for flow profiles and water temperature

- AWAC - for wave spectrums

- Anemometer

- Barometer - air pressure

- GPS

- Sonar for monitoring marine mammals

- Load cell integrated into mooring to measure mooring loads

- Hydrophone to record subsea acoustics The floating buoy 4 has a sealed inner chamber. Cables from the umbilical 2 can be passed through the wall of the buoy 4 without water ingress using the cable penetrator 0 that is provided in close proximity to the umbilical attachment point 9.

The energy storage device 7 that is housed within the buoy 4 is sized to provide continuous power to all navigational aids 6, on board sensors 11 , bottom mounted sensors 13 and radio telemetry 12 for extended periods of time without intervention.

The energy storage device may be rechargeable, such as a rechargeable battery. The buoy may therefore also house a recharging unit (not shown). This recharging unit may be adapted to use one or more of various means to recharge the storage device. For example, the buoy may incorporate a solar cell, powering the unit and recharging the storage device. The buoy may incorporate a simple wave-powered energy generation device, such as a simple water column or pump using the oscillation of the buoy itself, to power the unit. A tidal current generation device may be used, for example a simple turbine mounted in the nose of the monohull to take advantage of the tidal flow.

Referring to Fig. 3, the mooring unit 14 according to an embodiment is shown in plan elevation and has a shape that is favourable for reduced drag. A mooring attachment point 15 is provided to connect to one end of the umbilical 2 whilst the other end is connected to the buoy 1 itself. Mounting points are provided so that sea bed mounted sensors 13 may be installed in their optimal arrangement on the seafloor after deployment of the mooring unit 14. The necessary cables 16 are broken out from the umbilical 2 and connect to the sensors 13 to provide power to these devices subsea and to allow transmission of data to the buoy 4. The sensors 13 on board the mooring, in similar fashion to those on the buoy, can be of any number necessary for collecting the relevant data, subject to the weight or housing capacity of the mooring and the power capacity of the power system on the buoy and the power transfer capacity of the umbilical. The sensors can be of any type necessary for the desired data collection, for example they may include (not exclusively) optical or acoustic detectors, wave and pressure sensors, water velocity sensors, sensors measuring the load transmitted between the mooring and the buoy on the tether, chemical detectors, imaging devices, and the like.

The sensors may be mounted wherever on the mooring is needed to perform the function: for example, water velocity sensors may be mounted on top of the mooring, whereas sea bed sampling or monitoring detectors may be mounted on the underside or in contact with the sea bed. So called "bottom-mounted" sensors may be used, and/or the sensors may be mounted so that on deployment they are in close proximity to a sea bed or other floor environment, so that measurement of the local area, such as the boundary between the solid floor and particles suspended above, can be achieved. Such sensors may employ scoops or filters to measure aspects of the sea bed.

The sensors may be used for similar purposes to the buoy, and in addition for sea bed or benthic measurements, such as assessing a coefficient of friction of the sea bed, or composition of the sea floor, or pressure at the sea floor. The mooring may incorporate a sampling device, which can power and be commanded to sample the sea bed, or to drill a core from the sea bed for local or later analysis. Seabed sampling is typically a vital precursory activity to any form of seabed drilling. The device may be mounted so as to be deployable for sampling, and retractable for the normal, drag reducing state, and so that the sampling device and any mounting arm is not damaged or removed by drag forces. The mooring is typically designed to provide sufficient holding power to maintain the buoy in position. However, in embodiments, the mooring incorporates a deployable device or member for altering the holding power of the mooring. In a simple form this may be a hook or simple anchoring device, activated either by manual retraction of the umbilical when removing or re-siting the buoy/mooring, or by a local motor system (de)activating the hook or the like. The local motor system may be instructed from the buoy via the umbilical, for example in response to instructions received at the buoy from the shore station. The device may reduce the holding power to a certain degree, for example so that the mooring is now mobile to some extent, or may completely detach the mooring from the floor.

In one embodiment, this system is used to reduce the holding of the mooring, and to drag the mooring weight across the seabed. The mooring can be commanded to increase / reduce its drag and the point at which it slides (with mooring line loads and angle being recorded by sensors) and to enable the seabed friction coefficient to be measured, by on board sensors measuring movement, load on the umbilical, and the like. This may be used by marine energy device designers working on gravity based foundations.

In another embodiment, the deployable device is a foil or wing, such as a hydrofoil, mounted on the mooring and deployable into a tidal, current or similar water flow. The foil can be used to generate lift and unload the mooring, and the mooring can then be moved. The mooring can with careful control, for example by local motor actuation of the foil to vary angle, be remotely "flown" around, for example to traverse a tidal site to enable measurements to be taken from multiple points with one system and no vessel intervention. In an alternative embodiment, the mooring rather than, or in addition to, the buoy houses a/the power system. In this embodiment, power may be transmitted along the umbilical to the buoy to power components there, and used locally for the mooring devices and sensors. The power system may be an energy storage device as noted above for the buoy, and may be rechargeable, such as a rechargeable battery.

The mooring may therefore also house a recharging unit (not shown). This recharging unit may similarly be adapted to use one or more of various means to recharge the storage device, for incorporating a wave or tidal power unit. Other variations and modifications include: providing a data link with subsea devices, such as subsea high tension (HT) cables or marine energy related systems.

It is also appreciated that multiple systems could be deployed simultaneously in a chain-linked or an array form so as to collect data from a plurality of locations and feed the data into a grid array so as to present a wider picture of local variations. In such a configuration a command survey apparatus is adapted to collate the data from another 'satellite' survey apparatus and relay the data to, optionally via a booster station, to a shore-based receiver where the data is stored and analysed.

In an alternative embodiment the survey apparatus may be used to drag a mooring weight across the seabed. The survey apparatus may be modified to drag mooring weight is ideally capable of being commanded to increase/reduce its drag and the point at which the mooring weight drags/slides (mooring line load and angle recorded) would enable the seabed coefficient of friction to be measured. Such information is often needed in the design and construction of gravity based foundations. Optionally the survey apparatus may be adapted to power and command sea bed core sampling. Providing such data is important to precursory activity to any form of seabed drilling. Winch adjusted umbilical to enable remote repositioning of the survey apparatus.

A radio link is ideally employed to relay data in real time directly to a vessel to support vessel operations. Signals may be encrypted and/or time and/or date stamped.

Different transmission systems/data compression/ability to receive instructions and reconfigure data transmission etc.

It will be appreciated by those skilled in the art that the invention has been described by way of example only, and that a variety of alternative approaches may be adopted without departing from the scope of the invention, as defined by the appended claims.

Claims

1. A survey apparatus for collecting sensor data in a body of water, the apparatus comprising:

a buoy, including a first sensor means and a transmitter for transmitting collected sensor data to a receiver;

a mooring for the buoy, including a second sensor means; and an umbilical for connecting the buoy to the mooring, and for transmission of collected sensor data from the second sensor means to the buoy.

2. A survey apparatus according to Claim 1 , where the buoy comprises a power system, and wherein the umbilical is adapted to provide power from the power system to the second sensor means.

3. A survey apparatus according to Claim 1 or Claim 2, wherein the second sensor means is bottom-mounted on the mooring.

4. A survey apparatus according to Claim 3, wherein at least a portion of the second sensor means is mounted on a surface of the mooring for facing a floor of the body of water.

5. A survey apparatus according to Claim 4, wherein the at least a portion of the second sensor means is configured to contact the floor of the body of water.

6. A survey apparatus according to any preceding claim, wherein the buoy comprises one of: a monohull; a catamaran; and a small-waterplane- area twin hull.

7. A survey apparatus according to any of the Claims 2 to 6, wherein the power system comprises an energy storage means.

8. A survey apparatus according to Claim 7, wherein the energy storage means is rechargeable, and wherein the buoy comprises a power generation means for recharging the energy storage means.

9. A survey apparatus according to any preceding claim, wherein the umbilical comprises structural outer members connected to the buoy and to the mooring.

10. A survey apparatus according to any preceding claim, wherein the umbilical comprises a plurality of inner cable cores for transferring power and/or transmitting data.

11. A survey apparatus according to any preceding claim, wherein the first and/or second sensor means comprises an imaging device.

12. A survey apparatus according to any preceding claim, wherein the buoy further comprises a receiver for receiving remote control signals from a user device.

13. A survey apparatus according to any preceding claim, comprising a plurality of buoys and respective moorings, one of which buoys being a master buoy, wherein each of the other of the plurality of buoys is adapted to transmit data to the master buoy.

14. A survey apparatus according to any preceding claim, wherein the mooring comprises a member deployable to vary a holding power of the mooring.

15. A survey apparatus according to Claim 14, wherein the member is a hydrofoil.

16. A survey apparatus according to any preceding claim, wherein the mooring further comprises a sampling device for obtaining a sample of the floor of the body of water.

17. A buoy for a survey apparatus according to any preceding claim, the buoy comprising a sensor means and a transmitter for transmitting collected sensor data to a receiver.

18. A mooring for a survey apparatus according to any of the Claims 1 to 16, the mooring comprising a sensor means.

19. A method of installing a survey apparatus according to any of the Claims 1 to 16, the method comprising:

connecting the umbilical to the mooring and to the buoy;

deploying the mooring on a floor of the body of water; and deploying the buoy on a surface of the body of water.

20. A method of collecting sensor data in a body of water, comprising the steps of:

obtaining first sensor data from a buoy comprising a first sensor means;

using an umbilical connecting the buoy to a mooring, the mooring having a second sensor means, to receive second sensor data from the second sensor means; and

transmitting the collected first and second sensor data to a receiver.