Vessel, motion platform, method for compensating motions of a vessel and use of a stewart platform

The present invention relates to a ship with a movement compensation platform.

[0002] The invention also relates to a movement platform.

[0003] The invention further relates to a method of compensating for vessel movements.

[0004] The invention also relates to the use of a platform

Stewart according to any of the methods of claims 12

- 14.

[0005] movements

Water vessel with Stewart platform for ship compensation

The platform contains six cylinders

During use, known.

on is already maintained hydraulic, and motion sensors using sensors, are measured the movements of the relevant vessel. By means of these measurements, the position of the hydraulic cylinders is driven continuously such that the surface remains approximately stationary relative to the mainland.

In this way, the ship's movements are compensated and, for example, people or cargo can be transferred from the ship to a stationary structure at sea, or vice versa.

[0006] One of the objects of the invention is to improve the traffic platform, in particular a ship with a traffic platform.

surface, [0007] Another object of the invention is to improve the safety of the use of the ship and / or the movement platform.

[0008] At least one of these and other objectives has been achieved by means of a ship with a movement compensation platform, which platform is provided with at least one carrier for supporting, moving and / or transferring cargo, actuators for moving at least one carrier relative to the ship, preferably in six degrees of freedom, control system to drive actuators and motion sensors to measure the movement of the ship relative to the element in the environment, which measurements are used as input for the control system. Here, at least one at least partially passive pressure element is provided to exert pressure on the support during use to at least partially support it.

[0009] At least partially passive pressure element exerts back pressure on the carrier, whereby actuators can be at least partially relieved. As a result, actuators can be driven with relatively smaller pressure differences, so that greater precision is achieved.

[0010] At least one of said and / or other objectives has also been achieved by means of a traffic platform suitable in particular for a ship, such as described in any one of claims 1-9, which platform is provided with at least one support carrier, displacement and / or transfer of load, executive devices for moving the carrier, preferably in six degrees of freedom, relative to at least one fixed point of the executive devices, and a control system, the control system being designed to drive actuators for said relative carrier movement, while at least one at least partially passive pressure element is provided for at least partial load weight compensation.

[0011] In addition, at least one of said and / or other objects have been achieved by means of a method of compensating the movements of a ship, in which the movements of the ship are measured, in which the carrier is loaded so that the carrier is held substantially stationary relative to the element in environment, while the weight of the load is at least partially compensated by exerting a substantially constant back pressure on the carrier.

[0012] Preferably, a Stewart platform is used, the carrier being at least partially supported by at least one substantially passive pressure element, in particular a pneumatic means.

[0013] Attention is drawn to the fact that US Patent No. 5,947,740, which is considered to be the closest prior art, describes a simulator motion platform that, in addition to six actuators, includes a continuously driven (i.e. actively ) a hydraulic cylinder for receiving the load weight from other actuators. When moving the platform and setting it at different angles, the pressure on the hydraulic cylinder is measured continuously and actively adjusted to pressure changes. In contrast to this known pressure element, at least one pressure element according to the invention is at least partially passive. The at least one pressure element is also particularly suitable for a movement platform to compensate for the movements of the vessel, i.e., to keep the platform, at least carrier, approximately stationary relative to the element in the environment, such as, for example, a mainland, such as, for example , offshore structure, quay, or surrounding water, and / or a floating item such as another ship, etc. In the event of a fault in the actuator's active drive, for example, at least one pressure element will remain functional, thereby increasing the safety of the ship while maintaining relatively limited complexity.

[0014] In the following, the description of the invention will be explained based on a drawing illustrating embodiments of the watercraft, movement platform, method and application of the invention, in which the drawing:

Fig. 1 shows a watercraft according to the invention with part of a wind power plant;

Fig. 2 is a block diagram of an embodiment of the invention;

Fig. 3 is a schematic view of a moving watercraft according to the invention;

Fig. 4 is a schematic view of the traffic platform according to the invention;

Fig. 5 shows a schematic view of the movement platform according to the invention with an enlarged cross-sectional view of a part of the hydraulic-pneumatic cylinder;

Figures 6 and 7 show a schematic view of other traffic platforms according to the invention.

[0015] In the present description, identical or corresponding parts have identical or corresponding reference signs. In the drawing, the examples are given only illustratively. The parts used there are mentioned as examples only and should not be construed as limiting in any way. Other parts may also be used in the context of the present invention.

[0016] Fig. 1 schematically shows an embodiment of a watercraft 1 according to the invention. By

3, and vice versa. To it is provided with this platform will be the same vessel 1 cargo such as, for example, persons, animals, goods and / or other cargo may be transferred from vessel 1 to the frame or base, for example, wind power plant 2 at sea, ship 1 movement compensating platform 4 compensate for the movements of the watercraft 1 to keep the load relatively stationary relative to the wind power plant 2 so that, for example, persons such as personnel building the wind power plant, can move relatively safely. Ship 1 movements that can be compensated may include linear movements such as longitudinal oscillation (the ship moves from bow to stern), dredging (up and down) and transverse oscillations (sideways), and rotating movements such as mouse-clicking (bow from left to right), rocking (watercraft 1 tilts from left to right) and swinging (bow up and down). Of course, the motions of the watercraft 1 are often a combination of these linear and rotational motions.

[0017] This transfer from ship 1 or onto it should obviously not be limited to transfer to wind farms 2 and / or from them. In principle, the transfer can take place between the watercraft 1 and any other surrounding element 2. The watercraft 1 is suitable for transferring, for example, persons, animals and / or cargo to, in principle, any structure at sea, such as platforms at sea 3 and / or other constructions on water 3 etc. In certain embodiments, ship 1 according to the invention is designed to be transferred to any part connected to the mainland, such as a quay, flood embankment, cliffs, rugged rocks, (sea) bottom, etc. In some embodiments, ship 1 has been adapted for transferring to other moving parts and / or floating elements, such as, for example, other ships. To this end, by means of, for example, a camera, an optical sensor or the like, the movements of such a moving element can be recorded and can be compensated by active components in the movements of the carrier.

embodiment, [0018] In the illustrated movement compensating platform 4 is provided with six hydraulic cylinders 5 and a carrier 6. Such a movement platform 4 is known as a simulation platform as a "Stewart" platform. The carrier 6 of such a platform 4 is usually movable in six degrees of freedom. During operation, the carrier 6 will be kept, within the scope of the invention, substantially stationary relative to the wind power plant 2 by the hydraulic cylinders 5, by means of active drive. To this end, sensors such as motion sensors 7 and control system 8 are provided in / on the movement platform 4 and / or in / on the vessel 1, which are shown in Fig. 2. Sensors 2 measure the movements of the vessel 1, on example, rocking ship 1 in water 3. Using these measurements, during use, the hydraulic cylinders 5 are driven to keep the carrier 6 relatively stable relative to wind power plant 2.

The processing of these measurements and the active driving of the hydraulic cylinders 5 are the tasks of the control system 8. To this end, the control system 8 may comprise a microprocessor 13 and a memory 14. In the embodiment shown in Fig. 1 pneumatic means 9 are also provided, by means of which, during use, a passive pressure force is exerted on the carrier 6, preferably approximately counteracting the gravity force of the load and the carrier 6, so that the hydraulic cylinders 5 are at least partly unloaded. As a result, the required power of the hydraulic cylinders decreases and, in principle, relatively large loads can be supported. Also, for example, load shocks of the carrier 6 that can be caused by extreme wave motions can be at least partially damped by pneumatic means 9. In this specification, 'passive' may be understood to be non-driven, at least not continuously driven, or pneumatic means 9 will be able to react to the relative movements of the support 6 without being driven, practically without the lift provided by the exposed support. Of course, the pneumatic means 9 can be driven, at least in part, during certain periods, for example to set the pressure in the pneumatic means 9 at start-up, or at varying loads.

[0019] In the embodiment shown in Fig. 1, the pneumatic means 9 comprise at least one pneumatic cylinder 10, which is located approximately in the center of the compensating movement of the platform 4 and is connected by pipes 15 to a pressure compensator in the form of a reservoir 11 for buffering compressed air and a compressor 12 for compressing the air. After the pneumatic cylinder 10 and the reservoir 11 are filled with compressed air, after the load has been delivered, the cylinder 10 will remain under pressure and may still support at least part of the load. The pneumatic cylinder 10 has the property of moving passively along its longitudinal direction. Movements of the carrier 6 in the longitudinal direction of the cylinder 10 are accompanied by the compression and expansion of air in the cylinder 10 and the reservoir 11. Small pressure losses in the pneumatic cylinder 10 caused by, for example, friction can be measured and compensated by means of, for example, compressor 12 and / or control system 8. Such pneumatic means 9 are known as such from so-called 'plunging compensation' systems. By positioning this longitudinal direction in the direction of gravity, a large force, e.g. the gravity force of the carrier 6 and the load will be absorbed continuously by passive pneumatic means 9, and thus also in the event of a failure of the active components compensating for the movements of the platform 4 such as, for example, sensors 7, control system 8 and / or hydraulic cylinders. In certain embodiments, the pneumatic means 9 are preferably arranged in other directions, for example to compensate for the tilting movements of the carrier 6, for example after a fault has occurred. In this way, after a malfunction of an element such as cylinder 5, pneumatic means 9 can prevent the movement compensating platform from making a relatively dangerous movement, such as collapse, for example. Faults that may occur are, for example, an interruption in the power supply or the valves are stuck in the active hydraulic system.

Of course, also other, preferably passive, pressure systems 9 can be used in the context of the invention. In some embodiments, instead of and / or in addition to the pneumatic means 8, i.e. cylinder 10, at least one spring, e.g. a spiral spring and / or a gas spring, may be used as the passive element 10. The pneumatic means 9 may, in principle, contain various types of pressure elements such as, for example, hydraulic means and / or elastic means and / or a tensioning element, etc. Of course, one or more pressure elements may be used. Depending on, for example, the intended application, the desired accuracy and / or economic factors, one specific type, one specific number and / or location may be selected. The passive pressure system 9 provides safety because it is essentially reliable and can operate without continuous drive. Also, such a passive system 9 can maintain relatively limited complexity.

[0020] As mentioned, the pneumatic means 9 relieve the pneumatic cylinders 5. In certain embodiments, this results in less oil being circulated to keep the carrier 6 stable when the vessel moves.

1. In one embodiment, the pneumatic means 9 may be positioned by means of a compressor 12 to provide a pressure force that absorbs at least part of the weight of the carrier 6 and the load. Partially because of the mass inertia of the carrier 6 and load, and the constant pressure exerted by the cylinder 10 and the reservoir 11 on the carrier 6, in one embodiment, the carrier 6 will tend to remain approximately stationary relative to the mainland. As a result, the hydraulic cylinders 5 can compensate for the movements of the watercraft 1 using relatively small forces, i.e. keep the carrier 6 approximately stationary relative to the surrounding element.

[0021] In one embodiment, the pneumatic means 9 are also designed to prevent the specific movements of the vessel 1 from being intensified, for example by the forces exerted by the hydraulic cylinders 5 on the vessel 1. As shown in the exaggerated, schematic manner in Fig. 3, for example, such that if the watercraft tilts to a particular side, the hydraulic cylinder 5a extends to compensate for this tilting. At any time, in particular when the watercraft tilts back, it may be that the cylinder 5a is still driven to stretch, whereby the force F is exerted on the side of the vessel 1. This may intensify certain movements of the watercraft 1. As already explained, due to the pneumatic means 11, in particular the pneumatic cylinder 10 in Fig. 3, the forces exerted by and on the hydraulic cylinders 5 will remain relatively limited. Therefore, in some embodiments, this amount of movement remains limited when using the vessel. In another embodiment, the control system 8 includes an algorithm that can predict the delay and / or reversal of the movement of the vessel 1, so that the hydraulic cylinders 5 can be driven while predicting the respective motion of the accelerometer or vessel 1. Also in this way the intensification of movements of said watercraft 1 is prevented.

[0022] In specific embodiments, the motion sensors 7 include known motion sensors 7 such as for ship 1, for example dynamometers. Using known accelerometers, the movement of watercraft 1 relative to the mainland can be measured. Also, in specific embodiments, other types of sensors may be used, such as cameras, GPS (Global Positioning System), sensors using electromagnetic waves, sound waves, etc. Sensors 7 can measure the position of watercraft 1 relative to one or more elements in the environment, such as for example other watercraft 1 and / or mainland. The information received by the control system 8 from the motion sensors 7 is processed, for example, by pre-programmed algorithms such that the hydraulic cylinders 5 can be driven to keep the carrier 6 approximately stationary relative to the at least one element in the environment.

[0023] In specific embodiments, the control system 8 includes, in addition to the algorithms for driving hydraulic cylinders 5, a drive for predicting specific movements of the vessel 1. By recognizing, for example, a specific order of movements of the vessel 1, the control system 8 drives the cylinders 5 proactively . In this way, the forces of the hydraulic cylinders 5 on the vessel 1 can remain as low as possible, and an adverse effect on the vessel's movements, or at least their strengthening, can be prevented.

[0024] The operation of the embodiment of the motion platform 4 is approximately as follows. When the watercraft 1 is close to the wind power plant 2, the platform 4 is started. The pressure in the pneumatic means 9 is increased by means of the compressor 12 approximately to the weight of the carrier 6 and the load thereon so that the carrier 6 and the load, or part thereof, are supported by the pneumatic means 9. This can be done in cooperation with measurements from hydraulic cylinders 5 and / or motion sensors 7, with which the weight and movement of the vessel 1 can be measured relatively simply, of course, also other weight gauges and / or weight measurement methods and / or movements can be used to set the desired pressure in pneumatic means 9.

In addition, the velocities and motions of the vessel 1 are measured using motion sensors 7, which measurements are used as input to the control system 8. By continuously setting six cylinders 5, the carrier 6 will be able to remain practically stationary relative to the wind power plant 2 Then, the hatch or footbridge connected to the platform 4 and / or wind power plant 2 can be lowered to allow safe transfer of personnel and / or load.

5, will [0025] In some embodiments, the pneumatic means comprise several pneumatic cylinders 10. As shown in Fig. 4, one pneumatic cylinder 10 may be provided for one hydraulic cylinder 5. Here, in the event of a hydraulic cylinder malfunction, possible undesired movement of this cylinder 5 prevented by the respective pneumatic cylinder 10. By the same principle, the hydraulic cylinder 5 and pneumatic cylinder 10 can be integrated as shown in Fig. 5. Here, the integrated cylinder 5, 10 comprises, for example, an integrated piston with a passive, preferably pneumatic piston part 16 and an actively driven, preferably hydraulic piston part 17. It will be understood that, within the scope of the invention, several hydraulic 5 and / or pneumatic cylinders 10 may be provided. In the embodiments of Fig. 4 and 5, the passive cylinder 10, or the passive part of the cylinder 16, supports the largest part of the load, and the active cylinder 5, or the active part of the cylinder 17, sets the carrier 6.

[0026] As shown in the schematic embodiment of Fig. 6, it is also possible for several pneumatic cylinders 10 to apply pressure to or adjacent to the center of the carrier 6. Thus, safety can be further increased. Also, for example, with the tilting movement, as shown in Fig. 3, the pneumatic cylinder 10 in its best position can compensate for the movement of the vessel increasing the movement of the hydraulic cylinder 5. To this end, the pneumatic cylinders 10 can be positioned approximately in an upright position and placed under the carrier 6, which is very schematically shown in Fig. 7.

[0027] Instead of hydraulic cylinders 5, of course, a different number and type of actuators 6 may be used in the context of the invention. Other embodiments may include active pneumatic cylinders, linear motors, electric drive components, etc.

[0028] These and comparable variants as well as their combinations fall within the scope of the invention as set out in the claims. Of course, various aspects of various embodiments and / or combinations thereof can be combined with each other and be interchanged within the framework of the invention. Therefore, these embodiments should not be construed as limiting.

Technische Universiteit Delft

Proxy:

77P30205PL00

EP 1 993 902 B1