NO20220992A1

NO20220992A1 -

Info

Publication number: NO20220992A1
Application number: NO20220992A
Authority: NO
Priority date: 2022-09-19
Filing date: 2022-09-19
Publication date: 2023-08-21
Also published as: WO2024063656A1; NO347270B1

Description

A portable system and method for monitoring a marine lifting operation

Technical Field

[0001] The present invention concerns monitoring of marine lifting operations.

Specifically, the present invention concerns monitoring the lifting of a load to, or from, a floating structure during a marine lifting operation.

Background

[0002] During any lifting operation, it is important for operators to have information on the relative and / or absolute positions of a load, in order to perform a safe, fast, and accurate lifting operation. For marine lifting operations, such information is even more crucial, as the lifting device may be mounted on a floating platform or vessel. Thereby the lifting device may be subject to motions caused by wind, waves, currents, and / or mechanically induced motions resulting from the lifting itself. In order to monitor the relative positions of a load and a floating lifting device, systems exist, relying, for instance, on visual monitoring, and / or laser positioning. Often such systems are combined with GPS. In each case, the load is equipped with one or more markers and the lifting device, or the floating platform on which the lifting device is mounted, is provided with a corresponding sensor. The sensor observes the one or more markers, such that relative positions of the load and the lifting device can be computed, based on the sensor signal.

[0003] Recently, interest in floating structures has increased, in favor of bottomfixed installations. Bottom-fixed installations may be too expensive, have too much ecological impact, or simply be impractical, for instance, in deep-water environments. Floating structures may, e.g., include floating wind turbines or floating wind turbine bases, floating hydrocarbon exploration and production installations, or floating docking or transport systems. A lifting operation involving the transfer of a load to, or from, a floating structure by a floating lifting device does, however, add further complexity. As the floating structure may move under the influence of wind, waves, and / or currents, at least two sets of motions that must be taken into account when monitoring the lifting operation; the motions of the floating structure and of the load.

[0004] Consequently, there is a clear need to provide an improved system for monitoring marine lifting operations involving a floating structure. Preferably, such a system should be portable, such that it can be utilized during consecutive lifting operations involving different loads, and different corresponding floating structures. Furthermore, the system should preferably provide real-time information during the lifting operation. Thereby actual position and / or motion of the load relative to the floating structure may be compared with operational criteria. The operational criteria may for instance include limits on the relative position and / or motion of the load with respect to the floating structure, beyond which safe operation is no longer feasible. The actual position and / or motion of the load relative to the floating structure may also be compared with other relevant input, such as weather data and / or forecasts, wave data and / or forecasts, or current data and / or forecasts. All these comparisons may assist the operator in operational decision-making in proceeding, correcting or aborting the lifting operation.

Summary of the invention

[0005] The present invention concerns a system according to claim a portable system for monitoring the lifting of a load to, or from, a floating structure during a marine lifting operation. The portable system comprises at least one marker for reflecting a signal, a sensor unit for detecting the reflected signal, and a processing unit for computing position, velocity and / or acceleration data of the load relative to the floating structure. The at least one marker is attachable to the floating structure, and the sensor unit is attachable to the load. The present invention also concerns a method for monitoring the lifting of a load to, or from, a floating structure during a marine lifting operation, comprising providing a portable system according to the invention, attaching at least one marker to a floating structure, attaching the sensor unit to a load and receiving a reflected signal by the sensor unit. Position, velocity and / or acceleration data of the load relative to the floating structure are computed by the processing unit, based on the reflected signal. The invention also concerns a computer program product comprising machine readable instructions which, when the computer program is executed by a processing unit, cause the processing unit to compute position, velocity and / or acceleration data of the load relative to the floating structure. Advantageously, the portable system, can be transferred from one lifting operation to the next, providing increased flexibility. Furthermore, by computing position, velocity and / or acceleration data of the load relative to the floating structure, an ongoing lifting operation can be easily compared to operational criteria. Thereby, an operator may monitor and verify safe operation, or if necessary take corrective actions or even abort the operation.

Figures

[0006] Fig.1 schematically shows a system according to the present invention.

[0007] Fig.2 schematically shows of a detail of the system of Fig.1.

[0008] Fig.3 shows a flow-diagram of a computer program product according to the invention.

Detailed description

[0009] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying figures. Like components will be denoted by like reference numerals throughout the description and figures. Referring to fig.1, a portable system for monitoring of a marine lifting operation according to the invention for a marine lifting operation is schematically shown. A load 1 is lifted to, or from, a floating structure 2, by a lifting device 3. The lifting device 3 may be mounted on a floating platform or a vessel. The load 1 may, for instance, be a wind turbine component, such as a tower, a rotor-blade, or a nacelle. Alternatively, the load 1 may be a component, or a module, of a floating hydrocarbon installation. Further alternatively, the load 1 may be an aquaculture component, a cargo element, or an element recovered in a marine salvage operation, such as a part of a wreckage or retrieved cargo. The floating structure 2 may be a floating wind turbine base, a floating hydrocarbon installation, a vessel, a floating dock, or a floating aquaculture installation. The floating structure 2 may include a reference point and / or a landing platform, onto to which, or from which, the load 1 is to be lifted. A floating hydrocarbon installation may be a floating drill rig component, a floating production storage offloading (FPSO) vessel, or a floating dry-tree.

[0010] The portable system includes at least one marker 4. The marker 4 is attachable to the floating structure 2. Thereto, the marker 4 includes means for releasable attachment, such as suction means, adhesive means, magnetic means, or combinations thereof. Preferably, the means for releasable attachment are magnetic means. The magnetic means may include one or more electro-magnets, or one or more permanent magnets, such as switchable permanent magnets. Thereby, the marker may be attached in a gentle manner to the surface of the structure, so as to avoid damaging the surfaces of the floating structure. The marker 4 can advantageously be attached to one load for a first lifting operation, subsequently be released, and attached to a new load for a further lifting operation. Thereby, the marker can easily be transferred between different floating structures to be utilized in different marine lifting operations, regardless of the location or floating structure type. The system may include multiple markers, such as four markers 4, eight markers 4, or more markers 4. For complicated floating structure geometries, some markers may serve as a back-up in case one or more markers are obscured during the lifting operation.

[0011] The marker 4 further includes a reflective surface, such as a reflector, a polished surface, or a mirror surface. Alternatively, or additionally, the marker 4 may include a visual pattern, or a highly visible color, such as a fluorescent color. Thereby, the marker both reflects a signal and may be easily visible when placed on the load. Preferably, each marker 4 is provided with a unique identifier, such as an RFID tag, a barcode, a QR code, a serial number, or a visual tag. The identifier allows an operator to keep track of different markers, both during the lifting operation and when transferring markers between one lifting operation and the next. Furthermore, by providing each marker with a unique identifier it is possible to identify and track specific parts of the floating structure. For instance, a unique identifier may be associated to each structural element of the floating structure. Such identification may be particularly beneficial when a load must precisely matched to the geometry of the floating structure.

[0012] The portable system further includes a sensor unit 5. The sensor unit 5 is attachable to the load 1. Thereto, the sensor unit 5 includes means for releasable attachment 5a, such as suction means, adhesive means, magnetic means, or a combination thereof. Thereby, a reliable and secure releasable attachment of the sensor unit to the floating structure can be ensured.

Preferably, the means for releasable attachment 5a are magnetic means. The magnetic means may include one or more electro-magnets, or one or more permanent magnets, such as switchable permanent magnets. By utilizing electro-magnets or switchable permanent magnets, the sensor unit may be attached to the load in a gentle manner, so as to avoid damaging the surface of the load. The sensor unit 5 can thereby advantageously be attached to one load for a first lifting operation and subsequently be attached to a new load for a further lifting operation. Thereby the sensor unit can easily be transferred between different marine lifting operations, regardless of the location or the type of load.

[0013] With reference to fig.2, the sensor unit 5 includes at least one sensor 6, for recording a reflected signal 6a from the at least one marker 4. The sensor 6 converts the reflected signal 6a into signal data. Preferably, the signal data are real-time signal data. The sensor 6 may be an imaging device, such as an optical camera. Alternatively, the sensor 6 may be a laser sensor, such as a laser distance sensor, a time-of-flight sensor, or a lidar. Further alternatively, the sensor 6 may be an ultrasound sensor, a radar, or an IR sensor.

Preferably, the sensor 6 is a laser distance sensor. Advantageously, a laser distance sensor may achieve high accuracy whilst being operable in lowvisibility situations, such as rain or fog. Optionally, the sensor unit 5 may include multiple sensors 6. The multiple sensors 6 may be the same type of sensors, or may be different types of sensors. Preferably, the multiple sensors 6 include at least one wide-angle sensor, such as a wide-angle camera, a lidar, or a wide-angle ultrasonic transducer. The wide-angle sensor advantageously provides a situation overview, thereby providing an operator with valuable situation awareness during the lifting operation. Further preferably, the multiple sensors include at least one precision sensor, such as a laser distance sensor, or a time-of-flight sensor. Advantageously, the precision sensor provides accurate position, velocity and / or acceleration data during the lifting operation, thereby providing an operator with the required accuracy to monitor and control the lifting operation.

[0014] Turning, next, to the reflected signal 6a detected by the sensor 6, the reflected signal 6a may be reflected ambient light, a reflected laser signal, a reflected radar signal, a reflected sound or ultra-sound signal, or a reflected IR signal. The sensor unit 5 may further include a signal device 7, for emitting a signal 7a that may be reflected by the marker 4. The signal device 7 may be arranged to emit an optical signal, a laser signal, a sound signal, an ultrasound signal, or an IR signal. In operation, the signal device 7 may, for instance, emits a laser pulse signal 7a. The laser pulse signal 7a is reflected by a marker 4, and the reflected laser pulse signal 6a is received by the sensor 6. The sensor 6 then outputs the reflected signal data to a processing unit (described below), preferably in real-time.

[0015] The sensor unit 5 further includes a communication module 8, for transmitting signal data from the sensor 6 to a processing unit (described below). The communication module 8 is connected to the sensor 6. The communication module 8 may also be connected to the optional signal device 7, for transferring instructions thereto. The communication module 8 may include a Wi-Fi-unit, a blue-tooth unit, a 4G unit, a 5G unit, or a radio frequency unit. Preferably, the communication module 8 is configured to connect the sensor unit 5 to an Internet-of-Things (I-o-T) network.

[0016] Additionally, the sensor unit 5 may include a robotic arm 5b, arranged to adjust the position of the sensor unit 5. The robotic arm 5b is preferably installed between the releasable attachment means 5a and the sensor unit 5. The robotic arm 5b may be extendable, and may include one or more hydraulically or electrically driven, extendable elements. The robotic arm 5b preferably includes one or more joints. The robotic arm 5b is arranged to adjust the position of the sensor unit 5 along three spatial axis, for instance to compensate for movement of the load 1 during a lifting operation. The robotic arm 5b may further be arranged to perform rotational movements to adjust for roll, pitch and jaw movements of the load. The robotic arm 5b may be controlled by a processing unit (described below). Alternatively, the robotic arm 5b may be controlled by a processor included in the sensor unit 5. The robotic arm 5b may, for instance, be arranged to adjust the position of the sensor unit 5 such that the sensor 6 maintains a clear line of sight to the one or more markers 4 on the floating structure 2. The sensor unit 5 may further include a GPS module and / or a gyroscope module. The GPS module and / or the gyroscope module may be arranged to send position and / or orientation data to the processor, based on which the processor may adjust the robotic arm. The sensor unit 5 may optionally include a location beacon. Thereby, the precise location of the sensor unit may be transmitted to a processing unit (detailed below).

[0017] The sensor unit 5 further includes a power source 9. The power source 9 may preferably include a battery, such as a rechargeable battery. By including a power source, the sensor unit can operate autonomously, without the need for a physical connection to a power grid, improving the portability of the system. The power source may further include a solar panel, or a compact wind turbine, mounted on the sensor unit 5. Thereby, the battery may be charged during operation and autonomy of the system may be further increased.

[0018] The portable system further includes a processing unit 10, for processing the reflected signal data received from the sensor unit 5. Thereto, the

processing unit 10 includes at least a CPU, a memory module, and an I/O interface. Preferably, the processing unit 10 includes a screen. The screen may have touch-screen functionality. The processing unit 10 may be configured to receive input data, such as operational criteria for the lifting operation. The operational criteria may, for instance, include limits on the relative position, velocity and / or acceleration of the load with respect to the floating structure, beyond which a safe lifting operation is no longer feasible. The operational criteria may also include actual data and / or forecasts for weather, waves and / or currents. Current forecasts may, for instance, include forecasts on tidally induced currents. The processing unit 10 may further process the reflected signal data received from the sensor unit 5. The processing unit 10 may be configured to compute position, velocity and / or acceleration data of the load 1 relative to the floating structure 2, based on the reflected signal data 6a.

Preferably the position, velocity and / or acceleration data are computed in three dimensions. Furthermore, the position, velocity and / or acceleration data are preferably computed in real-time. Thereby, an operator can be provided with accurate real-time information on the lifting operation. Additionally, by computing the position, velocity and / or acceleration of the load relative to the floating structure, a lower complexity is achieved.

[0019] The processing unit 10 may further be configured to compare the computed position, velocity and / or acceleration data with the operational criteria. These comparisons may assist the operator in operational decision-making in proceeding, correcting, or aborting the lifting operation. The processing unit 10 may further be configured to send instructions to the sensor unit 5, such as instructions to emit a signal 7a and / or instructions to adjust the robotic arm 5b. The instructions may, optionally, be entered manually by an operator via an I/O interface or via a touch screen of the processing unit. The processing unit 10 is arranged to communicate with the communication module 8 of the sensor unit 5 via Wi-Fi, blue-tooth, 4G, 5G, or radio frequency signals. Preferably, the communication module 8 and the processing unit 10 are connected via an Internet-of-Things (I-o-T) network connection.

[0020] Furthermore, the computed position and / or motion data and, optionally, the operational criteria, may be visualized on a screen of the processing unit 10 and / or on an external screen, driven by the processing unit 10. Preferably, the visualization may be in real-time. The visualization may preferably be in the time domain and / or the spatial domain, such as a 3D visualization. Based on the computed position, velocity and / or acceleration data and optionally, on the corresponding visualization, an operator may monitor and compare an ongoing lifting operation and, for instance, take informed decisions on progress of the operation. The processing unit 10 preferably includes a GUI, for data visualization in the time domain and / or in the spatial domain. The GUI may also be provided with interactive functionality, allowing an operator to turn the sensor unit 5 on and off, to send instructions to the signal device 7, and / or to adjust the robotic arm in order to manipulate the position and / or orientation of the sensor unit 5.

[0021] The processing unit 10 may be located and / or operated remotely from the sensor unit 5. The processing unit 10 may, for instance, include a PC, a work station, a tablet computer, a smart phone, or a control panel. Advantageously, by utilizing a processing unit that can be located and / or operated remotely from the load, the energy demand on the sensor unit may be minimized.

Thereby the sensor unit can operate for longer times on a single charge, increasing autonomy of the system. The processing unit 10 may, for instance, be located on the floating platform or vessel on which the lifting device 3 is located.

[0022] A method for monitoring of a marine lifting operation includes providing a portable system according to the invention. The method further includes attaching at least one marker 4 to a floating structure 2. Optionally, multiple markers 4 are attached to the floating structure 2. For complex floating structure geometries, the risk of information loss due to one or more markers being obscured by parts of the floating structure during the lifting operation is thereby reduced. Next, the sensor unit 5 is releasably attached to a load 1. The marker 4 and the sensor unit 5 are placed such that reflected signals 6a from the marker 4 may be visible by the sensor 6 of the sensor unit 5. Operational criteria for the lifting operation may be entered, or downloaded, to the processing unit 10. The operational criteria may include limits for the position, the velocity and / or the acceleration of the load 1 relative to the floating structure 2, preferably in three dimensions. When approaching or exceed the limits for position, velocity and / or acceleration during a lifting operation, safe operation may no longer feasible. The operational criteria may further include data and / or forecasts on waves, weather and / or currents. Connection is established, between the communication module 8 and the processing unit 10. Optionally, the signal device 7 is activated, to send signals 7a to the marker 4. The signals 7a may be reflected by the marker 4.

[0023] The lifting operation commences as the lifting device 3 starts lifting the load 1 to, or from, the floating structure 2. During lifting, the sensor 6 detects reflected signals 6a from the at least one marker 4. The reflected signals 6a may include ambient light, or signals 7a originally emitted by the signal device 7. The communication module 8 receives reflected signal data from the sensor 6 and transmits the reflected signal data to the processing unit 10. Preferably, the reflected signal data are real-time data. Next, the processing unit 10 computes position, velocity and / or acceleration data of the load 1 relative to the floating structure 2, preferably in three dimensions. Preferably, the computed position, velocity and / or acceleration data are real-time data.

[0024] The computed relative position, velocity and / or acceleration data may be visualized on a screen of the processing unit 10 and / or on an external screen, driven by the processing unit 10. The computed data may be visualized by the processing unit 10 together with the operational criteria. The computed data may also be compared with the operational criteria by the processing unit 10. The comparison may, preferably, also be visualized. An operator may thereby infer real-time information on the progress of the lifting operation, to monitor and control the lifting operation. Thereby safe, fast, and accurate lifting may be performed, and uncertainty during lifting may be reduced. The lifting operation may, for instance, be paused, adjusted, or even aborted, if the computed data approach or exceed the limits set by the operational criteria. The processing unit 10 may emit a visible and / or an audible warning when the computed position, velocity and / or acceleration data approach or exceed the limits set by the operational criteria.

[0025] The invention further concerns a computer program product including machine readable instructions, as schematically shown in fig.3. The computer program product 11 may be configured to receive input 11a, including operational criteria for the lifting operation. The lifting operation then commences and the reflected signal from the one or more markers 4 on the floating structure 2 is detected by a sensor 6 of the sensor unit 5. The computer program is arranged to compute 11b position, velocity and / or acceleration data of the load 1 relative to the floating structure 2, from the detected reflected signal. Preferably, the position, velocity and / or acceleration data are computed in real-time and / or in three dimensions. The computer program product may further be configured to compare computed position, velocity and / or acceleration data to the operational criteria 11c. Finally, the computer program product may be configured to visualize the computed position, velocity and / or acceleration data and optionally, the operational criteria 11d and / or the comparison, within the GUI. The visualization may include plotting one or more graphs or figures within the GUI on a screen of the processing unit 10 or on an external screen, driven by the processing unit 10. The visualization may be in the time domain and / or the spatial domain. The computer program may further be arranged to initiate a visual and / or audible warning. The warning may, for instance, indicate how safe the operation is and / or if corrective actions are required, when the computed position, velocity and / or acceleration data approach and / or exceed the limits set by the operational criteria. For instance, when the computed velocity of the load 1 relative to the floating structure 2 approaches or exceeds a predefined limit in one or more spatial dimensions, the operator may be warned by an on-screen signal and / or an audible signal. The operator may then decide to proceed, adjust, or abort the lifting operation, in order to maintain operational safety.

List of references

[0026]

1 load

2 floating structure

3 lifting device

4 marker

5 sensor unit

5a means for releasable attachment 5b robotic arm

6 sensor

6a reflected signal

7 signal device

7a emitted signal

8 communication unit

9 power source

10 processing unit

11 computer program product

Claims

1. A portable system for monitoring the lifting of a load (1) to, or from, a floating structure (2) during a marine lifting operation, the portable system comprising: at least one marker (4) for reflecting a signal;

a sensor unit (5) for detecting the reflected signal (6a); and

a processing unit (10) for computing position, velocity and / or acceleration data of the load (1) relative to the floating structure (2);

wherein the at least one marker (4) is attachable to the floating structure (1), and the sensor unit (5) is attachable to the load (1).

2. The portable system according to claim 1, wherein the at least one marker (4) includes means for releasable attachment to the floating structure (2), such as magnetic means, suction means, or adhesive means, and wherein the sensor unit (5) includes means for releasable attachment (5a) to the load (1), such as magnetic means, suction means, or adhesive means.

3. The portable system of claim 1 or 2, wherein the sensor unit (5) further comprises a robotic arm (5b), for adjusting the position and / or the orientation of the sensor unit (5) during the lifting operation.

4. The portable system according to any preceding claim, wherein the sensor unit (5) includes at least one signal device (7) for emitting a signal (7a), such as a laser signal, a light signal, or an ultrasonic signal.

5. The portable system of any preceding claim, wherein the processing unit (10) is arranged to receive operational criteria as input, wherein the operational criteria may comprise limits on the relative position, velocity and / or acceleration of the load (1) with respect to the floating structure (2) and / or actual data and / or forecasts for weather, waves and / or currents.

6. The portable system of any preceding claim, wherein the processing unit (10) is arranged to compare computed position, velocity and / or acceleration data to the operational criteria, preferably in real-time.

7. The portable system of any preceding claim, wherein the processing unit (10) comprises a PC, a work station, a smartphone, a tablet computer, or a control panel.

8. The portable system of any preceding claim, wherein the sensor unit (5) further comprises a power source (9), the power source (9) preferably including a battery.

9. The portable system of any preceding claim, wherein the sensor unit (5) comprises multiple sensors, and wherein the multiple sensors comprise at least one wide-angle sensor and at least one precision sensor.

10. A method for monitoring the lifting of a load (1) to, or from, a floating structure (2) during a marine lifting operation, the method comprising:

providing a portable system according to any one of claims 1 – 9; attaching at least one marker (4) to a floating structure (2);

attaching the sensor unit (5) to a load (1);

receiving a reflected signal (6a) by the sensor unit (5); and

computing position, velocity and / or acceleration data of the load (1) relative to the floating structure (2) by the processing unit (10), based on the reflected signal (6a).

11. The method of claim 10, further comprising receiving operational criteria for the lifting operation as input by the processing unit (10), wherein the operational criteria may comprise limits on the relative position, velocity and / or acceleration of the load (1) with respect to the floating structure (2), and / or actual data and / or forecasts for weather, waves and / or currents.

12. The method of claim 11, further comprising comparing the computed position, velocity and / or acceleration data to the operational criteria and optionally, emitting a visible and / or an audible warning by the processing unit (10) when the computed position, velocity and / or acceleration data approach or exceed the operational criteria.

13. The method of any one of claims 10 - 12, further comprising visualizing the computed position, velocity and / or acceleration data and optionally, the operational criteria and / or the comparison of computed data with operational criteria, on a screen of the processing unit (10) and / or on an external screen.

14. A computer program product comprising machine readable instructions which, when the computer program is executed by a processing unit (10), cause the processing unit (10) to compute position, velocity and / or acceleration data of a load (1) relative to a floating structure (2).