NL2023134B1

NL2023134B1 - Telescopic gangway, motion compensation system, vessel, and offshore structure

Info

Publication number: NL2023134B1
Application number: NL2023134A
Authority: NL
Inventors: Johannes Delfos Ricco; Germain Verweij Alexander; Jan Göbel Arie; Leopold Albert Boudewijn Ronse Alexander; Anton Soonieus Alexander
Original assignee: Ampelmann Holding B V
Priority date: 2019-05-14
Filing date: 2019-05-14
Publication date: 2020-12-01

Abstract

A telescopic gangway, comprising a first and second part which are telescopable with respect to each other in a longitudinal direction to adjust a longitudinal length of the telescopic gangway, further comprising a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part, wherein the telescopic gangway is provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and/or second part.

Description

P120463NL00 Title: Telescopic gangway, motion compensation system, vessel, and offshore structure The invention relates to a telescopic gangway, in particular a telescopic gangway for providing access to and/or from a vessel.

The invention also relates to a motion compensation system comprising a telescopic gangway.

The invention further relates to a vessel comprising a motion compensation system with a telescopic gangway.

Telescopic gangways are generally known and are for example used for transferring loads, in particular people, to and/or from a vessel. Typically, telescopic gangways comprise a first part and a second part that is movable, in particular telescopable, relative to the first part in a longitudinal direction of the gangway. A distal end or tip of the gangway, in particular a distal end of the second part, is meant to be held and/or brought in close proximity with e.g. an offshore structure, such as an offshore wind turbine or an oil and gas platform. The tip of the gangway may for instance be connected to the offshore structure or may continuously be held in close proximity to the offshore structure e.g. by a constant pressure force. The second part can extend and retract in a longitudinal direction of the gangway enabling a flexible way of providing access to the offshore structure. In practice, for instance, a relative motion of the vessel with respect to the offshore structure which is connected to the fixed world, can at least partially be compensated by a telescoping movement between the second part and the first part. This telescoping movement occurs e.g. with a certain relative telescoping displacement, velocity and/or acceleration/deceleration.

In case the telescopic gangway is connected with its tip to the offshore structure, the motions of the vessel dictate the motion of the gangway, in particular the telescoping movement in the longitudinal direction of the gangway. This reactive state of the gangway is also referred to as a free float mode. On the other hand, in case the tip of the gangway is also actively held in close proximity to the offshore structure, the telescoping movement that compensates for the relative motion between the vessel and the offshore structure may partly be imposed by a drive and/or at least one (telescoping) actuator. This way, the telescoping movement of the gangway may be reactively and/or actively controlled.

Under certain circumstances, the telescoping movement, in particular e.g. the displacement, velocity and/or acceleration/deceleration, can hinder the transfer of people and/or loads from the first part to the second part and vice versa. The transfer may e.g. be hindered by sudden shifts in the telescoping movement between the second part and the first part or by relatively fast movements or accelerations between the respective parts. In particular, people using the gangway may experience discomfort due to the occurrence of e.g. relatively high velocities and/or accelerations.

An object of the invention therefore is to provide a telescopic gangway that mitigates at least one of the above mentioned drawbacks, while maintaining or improving ease of transfer of people and/or loads via the gangway.

Thereto, the invention provides a telescopic gangway, comprising a first and second part which are telescopable with respect to each other in a longitudinal direction to adjust a longitudinal length of the telescopic gangway. The gangway comprises a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part. The telescopic gangway 1s provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and/or second part.

By providing a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part, a relatively smooth transition between the first part and the transition part and between the second part and the transition part can be facilitated.

When the telescopic gangway is provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and/or second part, the relative movement of the transition part may be proportional to the telescoping movement. This way, at the transition that is bridged by the transition part, the telescoping movement may be distributed over a first movement between the first part and the transition part and a second movement between the second part and the transition part. Therefore, the movement of the transition part relative to the first and second part may be smaller than the telescoping movement between the first and second part. This may provide a smoother transition between the parts and improve the operative stability and ease of use of the gangway.

Advantageously, the telescopic gangway may be arranged such that when the first and second part telescopingly move with respect to each other during use, the coupling divides the telescoping movement substantially equally over the relative movement between the transition part and the first and second part respectively. In this manner, at the transition that is bridged by the transition part, the telescoping movement may be distributed equally over a first movement between the first part and the transition part and a second movement between the second part and the transition part. Thereby, the operative safety and stability e.g. for people using the gangway and/or loads being transferred on or by the gangway can be improved even further.

By further configuring the coupling to retard a transfer of at least part of the telescoping movement to the relative movement, the transfer of a sudden shift in telescoping movement between the first and second part may beneficially be delayed. Thereby, e.g. sudden shifts in and/or discomfort due to relative movement may be compensated and/or counteracted relatively effectively.

When the coupling comprises a drivetrain and/or at least one actuator that is configured to transfer telescoping movement to the relative movement, the relative movement may relatively easily be imposed by the telescoping movement between the first and second part.

By providing the telescoping gangway with a sensor device that is operatively connected to the coupling, wherein the sensor device is arranged to sense a magnitude of telescoping movement between the first and second part and to activate the coupling when the sensed magnitude of telescoping movement is greater than a threshold value, it may be facilitated that at least a part of the telescoping movement is only transferred to the transition part via the coupling under certain conditions. This way, wear of the telescoping gangway, in particular the coupling, may be counteracted whilst operative stability and ease of use of the gangway may be facilitated when the telescoping movements exceed a certain (predetermined) threshold value.

When a maximum extended longitudinal length of the telescopic gangway measured between a proximal end and a distal end of the telescopic gangway is shorter than a sum of the individual longitudinal lengths of the first and second parts, it may be achieved that the stability of the construction is enhanced relatively easily.

By arranging a longitudinal length of the transition part to be less than or equal to half of a maximum telescoping length, a relatively cost effective construction may be realized by e.g. counteracting use of excess material.

When the telescopic gangway comprises a guide for guiding the telescoping movement of the first and second parts with respect to each other, in particular for guiding a rolling and/or sliding telescoping movement with respect to each other, the telescoping movement may be facilitated using a relatively simple construction.

By providing at least one connecting element that movably connects the transition part with the first part, in particular at least at 5 and/or near an extremity of the transition part, and at least one second connecting element that movably connects the transition part with the second part, in particular at least at and/or near an opposing extremity of the transition part, the relative movement between the transition part and the respective first and second part may be e.g. facilitated or retarded relatively easily depending on the desired effect.

When at least one of the first, second and transition part is/are provided with at least one stop, in particular a stop comprising a damper, in particular which can collide with a further stop such as a protrusion on at least another of the first, second and transition part, and another of the first, second and transition part is are provided with at least one protrusion situated opposite the at least one stop, the telescoping movement and/or the relative movement may be limited in a relatively efficient and safe manner.

In an elegant way. the gangway may be provided with a drive and/or one or more telescoping actuators, in particular a series of telescoping actuators extending along a longitudinal direction of the gangway, for actively moving the distal end of the gangway into engagement with an offshore construction.

The invention further relates to a motion compensation system comprising a movable platform, wherein a telescopic gangway is connected to the platform, which gangway comprises a first and second part which are telescopable with respect to each other in a longitudinal direction to adjust a longitudinal length of the telescopic gangway, further comprising a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part, wherein the telescopic gangway 1s provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and/or second part. In particular, the telescopic gangway may include at least some of the features as described hereinabove.

The invention also further relates to a vessel, optionally comprising a motion compensation system including a movable platform as discussed above, wherein a telescopic gangway is connected to the vessel, optionally via the movable platform of the motion compensation system, which telescopic gangway comprises a first and second part which are telescopable with respect to each other in a longitudinal direction to adjust a longitudinal length of the telescopic gangway, further comprising a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part, wherein the telescopic gangway is provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and/or second part. In particular, the telescopic gangway may include at least some of the features as described hereinabove.

The invention furthermore relates to an offshore construction, optionally comprising a motion compensation system including a movable, wherein a telescopic gangway is connected to the offshore construction, optionally via the movable platform of the motion compensation system, which telescopic gangway comprises a first and second part which are telescopable with respect to each other in a longitudinal direction to adjust a longitudinal length of the telescopic gangway, further comprising a transition part that bridges a transition between the first and second part, wherein the transition part is movable in the longitudinal direction with respect to the respective first and second part, wherein the telescopic gangway 1s provided with a coupling that couples a telescoping movement between the first and second part with a relative movement of the transition part with respect to at least one of the first and second part, and wherein the coupling is configured to transfer at least a part of the telescoping movement to the relative movement.

In the context of this application, the coupling that is provided is meant to be construed as a coupling that couples the transition part to the first part, to the second part, to both the first and second part or e.g. a motion compensation system. This way, movement of the transition part, relative to the first and/or second part, is imposed by the telescoping movement between the first and second part. Additionally or alternatively, the coupling may actively move the transition based on the telescoping movement between the first and second part. For instance, based on a sensed telescoping movement between the first and second part, the coupling may drive movement of the transition part, in particular corresponding to substantially half of the telescoping movement.

Motion compensation systems, such as for compensating for vessel motions when transferring personnel and/or loads are known in the art. For example from the Ampelmann® system as disclosed in general in NL1027103, or systems disclosed in WO2012/138227 and WO2013/10564.

NL1027103 discloses a vessel with a Stewart type construction for compensating motions of a ship. The construction comprises a platform, borne on six hydraulic cylinders, and motion sensors. During use, with the aid of the sensors, the motions of the vessel are measured. With the aid of these measurements, the orientation and/or position of the cylinders is driven continuously so that the platform remains approximately stationary relative to the fixed world. A luffing gangway is connected to the platform. In this manner, motions of the vessel are compensated and for instance people or loads can be transferred from the vessel onto a stationary offshore construction, or vice versa.

WO2012/138227 discloses a vessel with a column supported on a deck of the vessel, and a gangway connected to the column, such that the gangway can rotate around a vertical axis of the column and can slew around an axis parallel to the deck.

WO2013/180564 discloses a vessel with a column and a gangway connected to the column for luffing, wherein the column is connected to a deck of the vessel by a two degrees of freedom pivot. Movement of the vessel can be compensated for by at least a combined movement of luffing and pivoting of the column in said pivot.

The terms gangway, gangboard, and gangplank may be used interchangeably throughout this application. Within the context of this application the term telescopable is meant to be construed as being movable, such as being able to move in and out of each other and/or with respect to each other, e.g. not unlike a telescope.

The invention will be further elucidated on the basis of exemplary embodiments which are represented in the drawings. The exemplary embodiments are given by way of non-limitative illustration of the invention. In the drawings: Fig. 1 shows a simplified schematic side view of a first embodiment of part of a telescopic gangway according to the invention; Fig. 2 shows a simplified schematic side view of a movable connection between a transition part and a first and second part of a gangway respectively of a second embodiment of a telescopic gangplank according to the invention; Fig. 3 shows a simplified schematic side view of a movable connection of a third embodiment of a telescopic gangplank according to the invention; Fig. 4A shows a schematic perspective view of a motion compensation system comprising a movable platform and a gangway, in a retracted state, connected to the platform according to a further aspect of the invention;

Fig. 4B shows a schematic perspective view of the motion compensation system of Fig. 4A with the gangway in an extended state; Fig. 4C shows a schematic perspective view of the motion compensation system of Fig. 4A with the gangway its maximum extended state.

In the figures identical or corresponding parts are represented with the same reference numerals. The drawings are only schematic representations of embodiments of the invention, which are given by manner of non-limited examples.

Fig. 1 shows a simplified schematic side view of a first embodiment of part of a telescopic gangway 1. The telescopic gangway 1 comprises a first part 2 and a second part 3. The first 2 and second part 3 are movable, in particular telescopable, with respect to each other in a longitudinal direction D. This way, a longitudinal length L of the telescopic gangway 1 may be adjusted. The longitudinal length L is measured between a proximal end 2’ and a distal end 3’ of the telescopic gangway 1. The telescopic gangway 1 further comprises a transition part 4 that bridges a transition T between the first part 2 and the second part 3. Transition T would be present between surfaces 5, e.g. walking surfaces or load bearing surfaces, of the first 2 and second part 3 had the transition part 4 not been provided. In the exemplary embodiment shown, the telescoping gangway 1 comprises a first transition T1 between surfaces 5a, 5c of the respective first 2 and transition part 4 and a second transition T2 between surfaces 5b, 5c of the respective second 3 and transition part 4.

The transition part 4 is movable in the longitudinal direction D with respect to both the first 2 and second part 3. The telescopic gangway 1 1s provided with a coupling 6. The coupling 6 couples a telescoping movement Al between the first 2 and second part 3 with a relative movement A2 of the transition part 4 with respect to at least one of the first

2 and second part 3. The coupling 6 is configured to transfer at least a part of the telescoping movement Al to the relative movement A2.

By way of example only, without limiting the scope in any way, the telescoping gangway 1 in a retracted state I may for instance have a longitudinal length L1 between around 3-30 m, such as for example around 25, 15, or 10 m. In the exemplary embodiment shown in Fig. 4A, the longitudinal length L1 is approximately 16 m in the retracted state I. A maximum extended length L2 of the telescoping gangway 1 in a maximum extended state III may e.g. be between around 5-50m, such as for example around 40, 25, 15 m. In the exemplary embodiment shown in Fig. 4C, the maximum extended longitudinal length L2 is approximately 25 m in the maximum extended state III. An extended state IT includes an extended longitudinal length L+dL between the longitudinal length L1 and the maximum extended longitudinal length L2. In the exemplary embodiment of Fig. 4B, the extended longitudinal length L+dL is approximately 21m in the extended state II. The maximum extended length L2 of the gangway 1 is shorter than the sum of the individual lengths of the first part 2 and the second part 3. As shown schematically in the exemplary embodiment of Fig. 4C, the first part 2 and the second part 3 comprise an overlap even when the telescopic gangway 1 in its maximum extend state IT.

The telescoping gangway 1 is provided with surface 5, e.g. walking surfaces or load bearing surfaces, that is divided into the surface 5a of the first part 2, the surface 5b of the second part, and the surface 5c of the transition part 4. In the exemplary embodiment of Fig. 1, surface 5c of the transition part 4 is provided above the surfaces 5a,5b of the respective first 2 and second part 3. Additionally or alternatively, the surface 5c of the transition part 4 may e.g. be provided in-between surfaces 5a, 5b of the respective first 2 and second part 3 (Fig. 2) or above the first 2 and second part 3 whilst a lower portion of the transition part 4 extends at least partly in-between the first 2 and second part 3 (Fig. 3). Also, at least one of the first 2, second 3 and transition part 4 may be provided with a transition element 7 that facilitates a relatively smooth transition between the surfaces 5a, 5b, 5c of the respective parts 2, 3, 4. In the exemplary embodiments of Fig. 1 and 2, the transition element 7 is embodied as a sloping surface provided at an end 4 of the transition part 4.

Although not shown, the gangway may additionally be provided with at least one load moving surface to accompany the walking surface 5, as e.g. known from NL2018734. This way, loads to be transferred to and/or from a vessel may be transferred along separate paths, such that they do not interfere with each other, which may increase the safety. The load moving surface may be provided on a common or separate carrier and may be provided with or without a load transition part between a load first part and a load second part as e.g. discussed on page 11 line 1 — page 13 line 14 and shown in Fig. 3, 3A and 3B of NL2018734, which is incorporated verbatim herein by reference.

Referring to Fig. 1 and Fig. 3, the transition part 4 is provided with at least one connecting element 8 such as in the form of a roller or wheel, such that the transition part 4 at or near the end 4 thereof is supported on the first part 2 with at least one connecting element 8, and at or near an opposite end 4” of the transition part 4 is supported on the second part 3 with at least one further connecting element 8’. This way the transition part 4 is movable relative to both the first part 2 and the second part 3.

Referring to Fig. 2 and Fig. 3, the coupling comprises a drivetrain 9 and/or at least one actuator 10 that is configured to transfer substantially half of the telescoping movement Al to the relative movement A2. When the first 2 and second part 3 telescopingly move with respect to each other during use, the coupling 6 divides the telescoping movement Al substantially equally over the relative movement A2 between the transition part 4 and the first 2 and second part 3 respectively.

In Fig. 2 according to a second embodiment of the telescoping gangway 1 the coupling 6, in particular a mechanical coupling, between the transition part 4 and the respective first part 2 and second part 3 is provided. The coupling 6 of Fig. 2 comprises a rack and pinion actuator 10’, that is extendable and retractable in the longitudinal direction D of the telescopic gangway 1. Two racks 11 are provided on either side of a pinion 12, e.g. circular gear with toothing, thereby partially enclosing the pinion 12 there between. A toothing 13 of the pinion 12 engages teeth 14 on both racks

11. Here, the pinion 12 is pivotably provided at the opposite end 4” of the transition part 4. Additionally or alternatively, the pinion 12 is e.g. pivotably provided at or near the end 4’ of the transition part 4 or the pinion 12 and a further pinion (not shown) may each be provided at or near the end 4’ and opposing end 4” of the transition part 4 respectively. Both the first part 2 and the second part 3 are each provided with a rack 11, which are arranged such that the toothing 14 of the racks 11 face each other. The gangway 1 may be provided with racks 11 extending along part of the longitudinal direction D of the gangway 1 e.g. on transverse sides of the gangway 1. The rack and pinion actuator 10° of the exemplary embodiment comprises a 1:1 gear ratio between the pinion 12 and respective racks 11, such that a ratio of on the one hand the movement of the second part 3 relative to the first part 2, and on the other hand the movement of each of the first 2 and second part 3 relative to the transition part 4, is fixed to be substantially 2:1. Thus, the second part 3 is arranged to move telescopingly to the first part 2 with a displacement, velocity and/or acceleration/deceleration that is twice as large as a displacement, velocity and/or acceleration/deceleration of the transition part 4 relative to the first 2 and second part 3 respectively. Thereby, during use, a telescoping movement Al at the first T1 and second transition T2 may be substantially halved reliably and relatively easily.

It should be clear to the skilled person that the rack and pinion actuator 10’ may additionally or alternatively be provided along part of a centerline of the gangway 1 and e.g. a guide (not shown) for guiding a rolling and/or sliding telescoping movement of the first 2 and second parts 3 with respect to each other may be provided on transverse sides of the gangway 1. Also, a series of pinions 12 may be pivotably provided, e.g. substantially evenly spaced, along a length of the transition part 4 to distribute the load and improve stability of the construction. The rack and pinion actuator 10° may be placed at any suitable location, such as, but not limited to below the walking surface 5. Additionally or alternatively, the rack and pinion actuator 10’ may be placed on an upper structure of the gangway 1, both below the walking surface 5 and on the upper structure, and/or in between handrail 15 of the respective first 2, telescoping 3, and/or transition part 4.

It should be noted, the rack and pinion actuator 10° may, additionally and/or alternatively, be electrically, hydraulically and/or pneumatically controlled. Preferably, the telescoping movement Al between on the one hand the second part 3 relative to the first part 2, and on the other hand the relative movement A2 of the transition part 4 with respect to thefirst 2 and second part 3 respectively, has a fixed ratio of 2:1.

Fig. 3 shows a schematic side view of a part of a partly cutout detail of a third embodiment of a gangway 1. Here, the coupling 6 comprises a cable and sheave system 16. The cable and sheave system 16 comprises a proximal sheave 17 connected to the first part 2, a telescoping sheave 18 connected to the second part 3, and a transition sheave 19 connected to the transition part 4. In this exemplary embodiment, a circumference 19’ of the transition sheave 19 is substantially half a circumference 20 of the respective proximal 17 and telescoping sheave 18. In this manner, the relative movement A2 at the first T1 and second transition T2 respectively, in particular of the transition part 4 relative to the respective first 2 and second part 3, is substantially half the telescoping movement A1 of the first 2 and second part 3 with respect to each other. It should be noted that instead of a cable and sheave system 16, a belt and sheave system can be provided. In a similar fashion as discussed above for the rack and pinion actuator 10’, the cable/belt and sheave system can be provided at any suitable location, such as, but not limited to below the walking surface 5, on the upper structure of the gangway 1, and/or in between the handrail 16 of the respective first 2, telescoping 3, and transition part 4.

The second part 3 and/or the transition part 4 is/are arranged to be extended or retracted telescopingly. To this end, the telescoping gangway 1 is preferably provided with a drive 21 and/or at least one telescoping actuator 22. In particular a series of telescoping actuators 22 extending along a longitudinal direction D of the gangway 1, for actively moving the distal end 3 of the gangway into engagement with an offshore construction (not shown). This is discussed in more detail below in light of the exemplary embodiment shown in Figs. 4A-C.

Also, referring to Figs. 1-3, actuators 10 are provided between the transition part 4 and the respective first part 2 and second part 3.

Additionally or alternatively, actuators such as counterweights, electric actuators, hydraulic actuators and/or pneumatic actuators may e.g. actively divide the telescoping movement Al substantially equally over the relative movement A2 between the transition part 4 and the first 2 and second part 3 respectively. Additionally or alternatively, the coupling 6 may comprise mechanisms to retard transfer of at least part of the telescoping movement Al to the relative movement A2 in a manner known to the skilled person. For instance, the coupling 6 may be provided with a resistance, such as a frictional resistance or counterweights, that slows down the transfer of telescoping movement Al to the relative movement A2. For example, the coupling may be provided with a drive and/or at least one actuator that actively retards said transfer.

Further, the coupling 6 may comprise a slipping mechanism that delays said transfer.

In Figs. 4A-C, the distal end 3’ of the telescopic gangway 1 is movable toward or away from an object (not shown), e.g. a vessel or an offshore structure such as an offshore wind turbine or an oil and gas platform, to and/or from which people and/or loads are to be transferred.

In principle, transfer may be carried out between a vessel and any other surrounding object.

In certain embodiments, the vessel is designed for transferring to any part connected to the fixed world, such as a quay, a levee, cliffs, steep rocks, (sea)floor etc.

In certain embodiments, the vessel has been made suitable for transferring to other moving elements and/or floating elements, such as, for instance, other vessels.

To that end, with the aid of, for instance, a camera, optical sensor or the like, the motions of such a moving element can be registered and be compensated by active or activatable components e.g. in the gangway 1. In Figs. 4A-C, the drive 21 and/or one or more telescoping actuators 22 are provided, in particular a series of telescoping actuators 22 extending along a longitudinal direction D of the telescopic gangway 1 and underneath the surface 5. The actuators 22 are extendable and retractable in the longitudinal direction D of the gangway 1 for altering a longitudinal length L of the gangway 1, or at least of the walking surface 5. The distal end 3’ of the telescopic gangway 1 comprises an engagement element 23 for engaging a constructional element of an offshore construction.

The distal end 3’ in the exemplary embodiment comprises a catch 24 open in a direction facing away from a proximal end 6’ of the gangway 1, in particular a substantially C- shaped catch.

Additionally or alternatively, the distal end 3° may be held in close proximity of an offshore construction, e.g. by a constant pressure force using the actuators 22. The exemplary embodiment further shows a motion compensation system 100, in particular a Stewart type system 100 comprising a platform

101 for compensating motions of a ship/vessel. The system 100 comprises a platform 101, borne on six hydraulic actuators 102, e.g. cylinders, and motion sensors 103. Telescopic gangway 1 is connected to the platform 100, in particular via the first part 2. The telescopic gangway 1 comprises a guide 25 for guiding the telescoping movement Al of the first 2 and second parts 3 with respect to each other. In the exemplary embodiment shown, the guide 25 is arranged as a guide assembly comprising a series of rollers that provided in-between the first 2 and second part 3 for guiding a rolling and/or sliding telescoping movement.

The first 2, second 3 and transition part 4 are each provided with at least one stop 26. The stop 26 comprises a damper 27. In addition, another of the first 2, second 3 and transition part 4 are provided with at least one protrusion 28 situated opposite the at least one stop 26.

During use, with the aid of the motion sensors 103, the motions of a vessel (not shown) are measured. With the aid of these measurements, the orientation of the hydraulic cylinders 102 is driven continuously so that the surface 101 of the platform 100 remains approximately stationary relative to the fixed world. In this manner, motions of the vessel are compensated and for instance people or loads can e.g. be transferred from the vessel onto a stationary offshore construction, or from a stationary offshore construction to the vessel as discussed in NL1027103 on page 1 line 35 - page 2 line 17 thereof, which is incorporated verbatim herein by reference.

It will be clear to the skilled person that the invention is not limited to the exemplary embodiment represented here. Many variations are possible. For example, a vessel may be provided with a motion compensation system, in particular a vessel with a column supported on a deck of the vessel, and a gangway comprising features as described above connected to the column, such that the gangway can rotate around a vertical axis of the column and can slew around an axis parallel to the deck. Further, a vessel with a column and a gangway comprising features as described above connected to the column for luffing, wherein the column is connected to deck of the vessel by a two degrees of freedom pivot. Movement of the vessel can be compensated for by at least a combined movement of luffing and pivoting of the column in said pivot.

Such variations shall be clear to the skilled person and are considered to fall within the scope of the invention as defined in the appended claims.

List of Reference Signs

1. Telescopic gangway

2. First part

2. Proximal end

3. Second part

3. Distal end

4. Transition part

4. End of the transition part 4”. Opposite end of the transition part

5. Surface 5a. Surface of the first part 5b. Surface of the second part 5c. Surface of the transition part

6. Coupling

7. Transition element

8. Connecting element

8. Further connecting element

9. Drivetrain

10. Actuator 10’. Rack and pinion actuator

11. Rack

12. Pinion

13. Pinion toothing

14. Rack toothing / teeth

15. Handrail

16. Cable/belt and sheave system 16’. Proximal sheave

18. Telescoping sheave

19. Transition sheave

19. Circumference of transition sheave

20. Circumference of proximal/telescoping sheave

21. Drive

22. Telescoping actuators

23. Engagement element

24. Catch

25. Guide

26. Stop

27. Damper

28. Protrusion

100. Motion compensation system

101. Platform

102. Hydraulic actuator

103. Motion sensor I. Retracted state II. Extended state UI. Maximum extended state T. Transition D. Longitudinal direction L. Longitudinal length L1. Retracted length dL. Telescoping length L2. Maximum extended length Al. Telescoping movement between transition part and first part A2. Relative movement between transition part and respective first and second part

Claims

Conclusions

A telescopic gangway, comprising a first and second portion telescopic relative to each other longitudinally to adjust a longitudinal length of the telescopic gangway, further comprising a transition portion bridging a transition between the first and second portions, the said transitional portion is longitudinally movable with respect to the respective first and second portions, the telescopic gangway being provided with a coupling such that a telescoping movement between the first and second portions causes movement of the transitional portion relative to the first and / or accomplishes the second part.

The telescopic gangway of claim 1, wherein when in use the first and second parts move telescopically with respect to each other, the coupling distributes the telescoping movement substantially evenly over the relative movement between the transition part and the first and second parts, respectively.

The telescopic gangway of claim 1 or 2, wherein the clutch is further configured to retard a transmission of at least a portion of the telescoping motion to the relative motion.

The telescopic gangway of any one of claims 1-3, wherein the coupling comprises a transmission and / or at least one actuator adapted to transmit at least part of the telescoping movement to the relative movement.

The telescopic gangway of any one of claims 1 to 4, comprising a sensor device operably connected to the clutch, the sensor device being arranged to sense a telescoping magnitude of movement between the first and second members and to activate the clutch when the detected telescoping motion magnitude is greater than a threshold value.

The telescopic gangway of any one of claims 1 to 5, wherein a maximum extended longitudinal length of the telescopic gangway measured between a proximal end and a distal end of the telescopic gangway is shorter than a sum of the individual longitudinal lengths of the first and second part.

The telescopic gangway of any one of the preceding claims, wherein a longitudinal length of the transition portion is less than or equal to half of a maximum telescoping length.

8. Telescopic gangway according to any one of the preceding claims, comprising a guide for guiding the telescoping movement of the first and second part with respect to each other, in particular for guiding a rolling and / or sliding telescoping movement with respect to each other.

A telescopic gangway according to any one of the preceding claims, comprising at least one connecting element movably connecting the transition part to the first part, in particular at least at and / or near one end of the transition part, and at least one second connecting element connecting the transition part. movably connects to the second part, in particular at and / or near an overhanging end of the transition part.

A telescopic gangway according to any one of the preceding claims, wherein at least one of the first, second and transition parts is provided with at least one plug, in particular a plug provided with a damper, and another with the first , second and transition part 1s provided with at least one stop located opposite the at least one stop.

A telescopic gangway according to any one of the preceding claims, comprising an engagement element at and / or near a distal end of the telescopic gangway, wherein, during use, the engagement element is adapted to engage a structural element of an offshore construction.

12. Telescopic gangway according to any one of the preceding claims, further comprising a drive and / or one or more telescoping actuators, in particular a series of telescoping actuators extending along a longitudinal direction of the gangway, for actively moving the distal end into contact. with an offshore construction.

The telescopic gangway of any one of the preceding claims, wherein the coupling comprises and / or is arranged as at least one of the following non-limiting list: a rack and pinion mechanism, a cable and pulley system, a belt and pulley system, an actively controlled actuator system including at least one electric and / or hydraulic actuator.

A motion compensation system comprising a movable platform, wherein a telescopic gangway, in particular a telescopic gangway according to any one of claims 1-13, is connected to the platform, which gangway comprises a first and second part telescopic in a longitudinal direction relative to each other. to adjust a longitudinal length of the telescopic gangway, further comprising a transition portion bridging a transition between the first and second portions, the transition portion being longitudinally movable relative to the respective first and second portions, the telescopic gangway is provided with a coupling such that a telescoping movement between the first and second part effects a movement of the transition part relative to the first and / or the second part.

A vessel, optionally comprising a motion compensation system with a movable platform according to claim 14, wherein a telescopic gangway, in particular a telescopic gangway according to any one of claims 1-13, is connected to the vessel, optionally via the movable platform of the motion compensation system. of claim 14, the telescopic gangway comprising a first and second portion telescopic relative to each other longitudinally to each other to adjust a longitudinal length of the telescopic gangway, further comprising a transition portion bridging a transition between the first and second portions, wherein the transition part is longitudinally movable with respect to the respective first and second parts, the telescopic gangway being provided with a coupling such that a telescoping movement between the first and second part causes a movement of the transition part relative to the first and / or or move the second movement rkstitutes.

An offshore structure, optionally comprising a motion compensation system with a movable platform according to claim 14, wherein a telescopic gangway, in particular a gangway according to any one of claims 1-13, is connected to the offshore structure, optionally via the movable platform of the motion compensation system of claim 14, which telescopic gangway comprises a first and second portion telescopic relative to each other longitudinally to adjust a longitudinal length of the telescopic gangway, further comprising a transition portion bridging a transition between the first and second portions, wherein the transition section is longitudinally movable relative to the respective first and second sections, the telescopic gangway 15 provided with a coupling such that a telescoping movement between the first and second sections causes movement of the transition section relative to the first and second sections. / or the second part.