BR102019013799A2 - POSITION MEASUREMENT METHOD AND SYSTEM FOR USE IN A FLOATING INSTALLATION - Google Patents

Abstract

“Position measurement method and system for use in a floating installation” a floating drilling installation comprising a machine having a base and a pivotable part that is mounted on and pivotable with respect to the base around a rotating axis, and a position measuring apparatus for measuring the position of the pivotable part of the machine base, the position measuring apparatus comprising a first inclinometer which is mounted on the pivotable part in order to provide a tilt signal representing the absolute tilt angle of the pivotable part , a second inclinometer that is mounted on the base to provide a tilt signal representing the absolute tilt angle of the base, and a processor that is connected to the first and second inclinometers in order to receive first and second tilt signals from the first and the second inclinometers respectively, and that is programmed to determine the ap positioning the pivotable part of the machine in relation to the base using both the first and the second inclination signs.

Description

"POSITION MEASUREMENT METHOD AND SYSTEM FOR USE IN A FLOATING INSTALLATION [0001] The present invention relates to a position measurement method and system for use in a floating installation such as a drilling rig for use in drilling a borehole well.

[0002] It is known for machines in a floating installation such as a marine drilling rig to have a part that is pivotable in relation to a machine base. Such a machine can, for example, be a tube manipulator with a pivotable tube manipulator arm. During the operation of the machines on the drilling rig, it is desirable that an operator or operating system is able to determine the position of the pivotable part in relation to the machine base and / or other equipment on the rig. This may be necessary, for example, to prevent the pivotable part from colliding with another piece of equipment or part of the probe, or in the case of a tube handler to determine if it is in the correct position in relation to a tube to activate a pickup to wrap with and maybe pick up the tube.

[0003] Typically this is achieved using measurements from a plurality of sensors including encoders, linear measurement sensors, proximity sensors, ultrasonic sensors, laser sensors, radar sensors, and LIDAR sensors, and / or motion detection linear using CCTV.

[0004] It is an object of the present invention to simplify, and therefore reduce the cost of, the equipment needed to monitor the position of a pivotable part

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2/19 of a machine relative to the machine base.

[0005] In accordance with a first aspect of the invention we provide a floating drilling installation comprising a machine having a base and a pivotable part that is mounted on and pivotable with respect to the base around a rotating axis, and a measuring device for measuring position to measure the position of the pivotable part of the machine, the position measuring apparatus comprising a first inclinometer which is mounted on the pivotable part in order to provide a tilt signal representing the absolute tilt angle of the pivotable part, a second inclinometer which is mounted on the base to provide a tilt signal representing the absolute tilt angle of the base, and a processor that is connected to the first and second inclinometers in order to receive first and second tilt signals from the first and second inclinometers respectively, and which is programmed to determine the position of the pivotable part of the m machine in relation to the base using both the first and the second slope signs.

[0006] The processor can be programmed to use information regarding the length of the pivotable part and the height of the pivotable part in relation to the base, and the first and second inclination signals to determine the location of an end of the pivotable part in relation to the base.

[0007] The pivotable part may comprise an arm having a first end that is mounted on the base, with a tool mounted on a second end of the arm.

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3/19 [0008] The machine can be an apparatus for handling the tube, and the tool comprises a clamp operable to wrap with a tubular element so that the tubular element can be lifted by the arm.

[0009] The base can be mounted on or an integral part of the floating installation.

[0010] In accordance with a second aspect of the invention, we provide a method of measuring the position of a pivotable part of a machine having a base, the pivotable part being mounted on and pivotable with respect to the base around a rotating axis, using a position measuring device comprising a first inclinometer which is mounted on the pivotable part and which provides a tilt signal representing the absolute angle of inclination of the pivotable part, a second inclinometer which is mounted on the base and which provides a tilt signal representing the absolute angle of inclination of the base, the method comprising

a) use both the first and second inclination signals from the first and second inclinometers respectively to determine the position of the machine's pivotable part in relation to the base.

[0011] The method may include using information regarding the length of the pivotable part and the height of the swiveling part in relation to the base, and the first and second signs of inclination to determine the location of an end of the pivotable part in relation to the base.

[0012] In accordance with a third aspect of the invention we provide a data processing apparatus comprising means for carrying out the method according to the first aspect of the invention, the data processing apparatus

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4/19 data being configured to process the first and second tilt signals to determine the position of the pivotable part of the machine in relation to the base.

[0013] The data processing apparatus may be provided with information regarding the length of the pivotable part and the height of the swiveling part in relation to the base, and be programmed to use that information and the first and second tilt signals to determine the location of one end of the pivotable part in relation to the base.

[0014] In accordance with a fourth aspect of the invention, we provide a computer-readable medium comprising instructions that, when executed by a computer, cause the switch to perform step one of the method according to the second aspect of the invention.

[0015] Instructions can, when executed by a computer, cause the computer to use information regarding the length of the pivotable part and the height of the swiveling part in relation to the base and the first and second signs of inclination to determine the location of a end of the pivotable part in relation to the base.

[0016] According to a fifth aspect of the invention we provide a position measuring device for measuring the position of a pivotable part of a machine having a base, the pivotable part being mounted on and pivotable with respect to the base, the apparatus comprising a first inclinometer that is adapted to be mounted on the pivotable part in order to provide a tilt signal representing the absolute angle of inclination of the pivotable part, a second inclinometer that is adapted to be

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5/19 mounted on the base to provide a tilt signal representing the absolute tilt angle of the base, and a processor that is connected to the first and second inclinometers in order to receive first and second tilt signals from the first and the second inclinometers respectively, and which is programmed to determine the position of the pivotable part of the machine in relation to the base using both the first and the second inclination signals.

[0017] According to a sixth aspect of the invention we provide a position measurement system comprising a machine having a base and a pivotable part which is mounted on a pivot with respect to the base around a rotating axis, the system comprising a first inclinometer is mounted on the pivotable part to provide a tilt signal representing the absolute tilt angle of the pivotable part, a second inclinometer that is mounted on the base to provide a tilt signal representing the absolute tilt angle of the base, and a processor that is connected to the first and second inclinometers in order to receive first and second inclination signals from the first and second inclinometers respectively, and which is programmed to determine the position of the machine's pivotable part in relation to the base using both the first as well as the second signs of inclination.

[0018] The processor can be programmed to determine the position of the machine's pivotable part in relation to the base using information regarding the height of the pivot axis in relation to the base, and the length of the pivotable part, along with the first and second signs of slope to determine the position of one end of the

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6/19 pivotable part in relation to the base.

[0019] The pivotable part may comprise an arm having a first end that is mounted on the base, with a tool mounted on a second end of the arm.

[0020] The machine can be an apparatus for handling the tube, the tool comprising a clamp operable to wrap with a tubular element so that the tubular element can be lifted by the arm.

[0021] The modalities of the invention will now be described, by way of example only, with reference to the accompanying drawings of which, [0022] Figure 1 shows a schematic illustration of a floating drilling installation according to the first aspect of the invention, [0023] Figure 2 is a schematic illustration of a position measuring device suitable for use in the floating drilling installation illustrated in Figure 1, [0024] Figure 3 is a graph illustrating the position of the device's pivotable arm for handling of the pipe shown in Figure 1 with the platform of the drilling rig floating in a horizontal position, [0025] Figure 4 is a graph that illustrates the position of the pivotable arm of the rig for handling the pipe shown in Figure 1 with the platform of the drilling rig. floating drill installation tilted around the x-axis, [0026] Figure 5 is a graph illustrating the position of the pivotable arm of the rig the tube shown in Figure 1 with the floating drilling rig platform tilted around the x and y axes,

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7/19 [0027] Figure 6 is a graph that illustrates, in plan view, the position of the pivotable arm of the rig for handling the pipe shown in Figure 1 with the floating drilling rig platform tilted around the x and y axes, and the arm rotated around the z-axis, [0028] Figure 7 is a graph that illustrates the position of an upward-facing pivotable arm mounted on a base that is tilted around the x and y axes, and [0029] Figure 8 is a graph illustrating the position of an alternative configuration of the pivotable part with three relatively pivotable connections.

[0030] Referring now to Figure 1, there is shown a floating installation 10 according to the invention, which, in this embodiment comprises a floating drilling platform 11. Mounted on the drilling platform 11 is a probe 12 from which the column drilling rig 14 is suspended, the drilling rig 14 extends downwards in a marine riser tube 16 which is suspended from the bottom face of the platform using a riser tube tensioning system 18. A tube manipulator device 20 is also provided on the platform 11, and is operable for a drill pipe lifting section 21 for insertion into the drill column 14. The tube manipulator apparatus 20 is provided with an arm 22 having a first end which is mounted on a base 24 of the apparatus, and a second end on which a clamp 26 is mounted which is operable to grasp and hold on a section of drill pipe 21, so that the drill pipe 21 is high in a desired position.

[0031] All of these resources are conventional

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8/19 on drilling platforms.

[0032] The floating installation 10 is also provided with a position measuring device comprising a first inclinometer 28 which is mounted on the arm 22 of the tube manipulator apparatus 20 and which provides an inclination signal representing the absolute angle of inclination of the arm 22 (that is, the angle of inclination of the arm 22 with respect to the ground), and a second inclinometer 30 which is mounted on the platform 11 and which provides an inclination signal representing the absolute angle of inclination of the platform 11 (that is, the inclination platform 11 in relation to the ground). The position measuring apparatus also comprises a processor 32 which is connected to both the first and second inclinometers 28, 30 in order to receive first and second inclination signals from the first and second inclinometers 28, 30 respectively, and which is programmed to determine the position of the arm 22 in relation to the platform using both the first and the second inclination signals. The processor 32 is connected to a virtual display unit 34 which is configured to display the position of the end of the arm 22 for viewing by an operator. The position of the end of the arm 22 can thus be used by the operator of the control equipment by means of which the arm 22 is moved.

[0033] Processor 32 can also be connected to the control equipment so that the arm can be automatically moved to a desired position.

[0034] The position measuring device is illustrated in Figure 2.

[0035] Inclinometers suitable for use in

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9/19 position measuring devices are widely available, and examples of suitable inclinometers are the inclinometers Q20L60 and QR24 supplied by Hans Turck GmbH & Co. KG (Turck ”).

[0036] With reference now to Figure 3, a graph is shown that illustrates the position of the arm 22, which will be used to explain how the first and second signs of inclination can be used to determine its position.

[0037] In this example, the position of the arm 22 is illustrated in relation to the three orthogonal axes - the x and y axes that form a plane that is generally parallel to the earth's surface, and a z axis that is perpendicular to the earth's surface. These axes are therefore fixed in space. At present, it is considered that the plane formed by the x and y axes rests on a plane corresponding to the surface of the platform 11.

[0038] O arm 22 is pivotable around of the axis A, that it's parallel to axis x, and therefore it moves on the plan formed by the axes y and z. In this example, the first

the end of the arm 22 is mounted on the base 24 so that it is raised above the platform by a height h, and the arm 22 is pivoted so that its second end, and therefore the clamp 26, is lower than its first end , in order to pick up a section of drill pipe 21 on the platform 11.

[0039] The arm 22 has a length l, and the first inclinometer 28 is arranged to measure the angle of the arm 22 in relation to the B axis, which is a horizontal axis parallel to the y axis, and to the longitudinal axis of the arm 22. This angle measured is designated 0 ^meas . from trigonometry

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Basic 10/19, it will be assessed that the y _and z coordinates (Y ^meas _and Z ^meas ) of the second end of arm 22 (marked as P ^meas ) in relation to platform 11, can be determined using the measured angle and the known length of arm 22 using the following equations:

Y ^meas = l _cos and ^meas

Z ^meas = h - l sin e ^meas [0040] The desired position of the second end of the arm 22, that is, the position of the arm 22 which places the clamp 26 in the right position to be operable to grasp the drill pipe 21, is marked as point P in Figure 3, and represented by the y and z coordinates of Y and Z. Again, using basic trigonometry it will be assessed which angle of inclination of the arm 22 when the clamp 26 is in the desired position (designated θ) can be determined using these coordinates and the following equations:

θ = cos ^-1 (Y / l) [0041] However, as mentioned above, inclinometers 28, 30 measure an absolute angle of inclination, that is, the angle of inclination in relation to the ground. As such, this method will only work if both the base 24 of the tube manipulator apparatus 20 and the drill pipe 21 are stationary, and the platform 11 remains parallel to the earth's surface. It will be appreciated, however, that as both are located in a floating installation

10, this is unlikely to happen. The floating installation will move with the agitation of the ocean, and / or as a result of changes in weight or weight distribution on the platform

11. If this movement were purely vertical or horizontal translational movement, the above method would be

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11/19 applicable, but it will be assessed that it is also unlikely. It is much more likely that the floating installation will tilt during operation of the tube manipulator 20.

[0042] The effect of this inclination of platform 11 in the above method will be described with reference to Figure 4. For the sake of simplicity, in the first example, platform 11 is considered to be tilted by an angle of -τ (negative because it represents rotation counterclockwise) about an axis that is parallel to the x axis. The surface of platform 11 is now in a plane formed by the x-axis and a new y-axis illustrated in Figure 4, and is perpendicular to the new z-axis. The second inclinometer 30 is configured to determine the angle of the earth in relation to the platform 11, certainly, and is arranged to measure the angle of the y 'axis in relation to the horizontal, so that the inclination signal from the second inclinometer represents the angle -τ.

[0043] This inclination of platform 11 will result in upward movement of the drill pipe 21 in space, and therefore upward movement from the desired position of the second end of the arm 22 to a new position in relation to the platform 11 marked as P ^meas ' on Figure 4.

[0044] Although the arm 22 and, therefore, the first inclinometer 28 also tilted through the same angle, as the inclinometers provide a signal that represents the absolute angle of inclination, the signal of inclination from the first inclinometers 28 still represents the tilt angle of the arm 22 in relation to the B axis. In order to calculate the position of the arm 22 in relation to the platform 11, it is necessary to use the signals from

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12/19 both inclinometers 28, 30 as follows:

Y ^meas = l cos (0 ^meas - (- τ)) = l cos (0 ^meas + l)

Z ^meas = hl sin (0 ^meas - (- τ)) = hl sin (0 ^meas + T) [0045] It will be evaluated that if arm 22 is moved so that its angle of inclination is 0 as calculated above, the clamp 26 will no longer be in the right place to grab the drill pipe 21. In fact, if platform 11 tilts far enough, and the desired position is close to the surface of platform 11, pivoting arm 22 to an angle 0 could cause the end of arm 22 to collide with the surface of platform 11.

[0046] To move the arm 22 so that the clamp 26 is in the desired position in relation to the platform 11 (that is, in the position represented by the coordinates y 'and z', Y and Z), the arm 22 must now be moved so that its angle of inclination in relation to the B axis is 0 - τ, or cos ¹ (Y / l) - τ.

[0047] It is certainly unlikely that the floating installation 10 will only tilt around an axis that is exactly parallel to the rotation axis of the arm 22. It is likely that the floating installation will incline such that the angle of the platform surface 11 changes with respect to both x and y axes. When this happens, arm 22 will be rotated in space around its longitudinal axis, and when pivoted around axis A it will pivot in a plane that is at an angle to the vertical. As such, the plane including the arms 22 and the y and z axes and will no longer be on a plane parallel to the B axis. The surface of platform 11 is now on a plane formed by a new x axis and a new one.

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13/19 y-axis '' illustrated in Figure 5, and is perpendicular to the new z-axis ''. The x '', y '' and z '' axes are in the same position in relation to platform 11 as the original x, y and z axis, but are in different positions in space. The arm 22 now pivots around an A '' axis that is parallel to the x '' axis, to move in a plane formed by the x '' and y '' axes, but that plane is no longer vertical.

[0048] Certainly, the first inclinometer 28 measures the angle of the arm 22 in relation to a horizontal axis that is in a flat vertical in which the arm 22 extends. As such, the angle measured by the first inclinometer 28 will be slightly less than the angle of the arm 22 with respect to the y-axis. '' The same applies to the second inclinometer 30 as well. Reading this inclinometer 30 will not exactly represent τ the angle of the y '' axis to the horizontal in the plane formed by the y '' and z '' axes it will also give an angle that is slightly smaller.

[0049] Having said this, in practical terms, the general angle of inclination of platform 11 is relatively small, and the differences in angle described above will be even smaller. The inaccuracy in terms of the y '' coordinate of the end of the arm 22 introduced by this discrepancy is related to the cosine of the angle, which for small angles is approximately equal to 1. As such, it is possible to ignore this discrepancy, and use the inclination from the first and second inclinometers 28, 30 to represent 0 ^meas and τ in the above equations, in order to determine the position of the end of the arm 22 even when the platform 11 tilts in relation to both the x and y axes.

[0050] It will also be assessed that arm 22 can

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14/19 can also be configured to pivot around an axis of rotation that is perpendicular to the plane of the platform 11, in order to pick up sections of drill pipes 21 from different points on the platform 11.

[0051] In an modality, this is achieved configuring the base 24 to be pivotable about platform 11 in lathe in an axis which is perpendicular to the platform 11. Huh this case, the second inclinometer

it is advantageously mounted on the base 24, so that it rotates with the base, and always measures the angle of inclination of the platform in the same direction in relation to the arm 22. In other words, regardless of the rotation of the arm 22, the axis of the second inclinometer 30 and the arm 22 always rests in a single plane - a plane formed by a y-axis '' which is in the plane of platform 11 and the B axis of the first inclinometer 28.

[0052] In this case, the height of the end of the arm 22 above the surface of the platform 11 (ie, Z ^meas ) can be determined as before, using the equation:

Z ^meas = hl sin (0 ^meas - (- τ)) = hl sin (0 ^meas + T) [0053] However, if the total position of the end of the arm 22 in relation to the platform 11 is necessary, it is necessary that the device position measurement device also includes an orientation sensor that is connected to processor 32 and that is configured to provide processor 32 with a signal representing the angle λ through which base 24 rotated, relative to a reference plane that extends perpendicular to the plane of the platform 11 and where the axis of rotation of the base 24 is located.

[0054] Processor 32 uses inputs from

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15/19 of inclinometers 28, 30 to determine 0 ^meas , the angle between arm 22 and the horizontal axis B, and angle τ, the angle of the y axis''' to the horizontal, and the angle λ to determine the position of the y axis''' in relation to platform 11.

[0055] For example, if the reference plane extends along the y axis '' in the plane of platform 11, and the arm 22 has been rotated clockwise around the z axis '' through an angle λ, as illustrated in the flat view of platform 11 shown in Figure 6, the position of the end of the arm 22 in relation to the x '', y '' and z '' axes on platform 11 can be calculated as follows:

X ^meas = _s i _n λ.Τ cos (0 ^meas + T)

Y ^meas = cos λ.! cos (0 ^meas + T)

Z ^meas = hl sin (0 ^meas + T) [0056] Alternatively, if the second inclinometer 30 is mounted on the platform 11, and therefore does not rotate with the base 24, or if the arm 22 rotates about an axis that is perpendicular to the plane of platform 11, it is necessary for the second inclinometer 30 to be biaxial, that is, to measure inclination in relation to two orthogonal axes, the orientation of which in relation to the reference plane, is known. The processor 32 is, in this case, programmed to use the signals from the second inclinometer 30, and the signal from the orientation sensor, to determine the angle of inclination of the y-axis in relation to the horizontal, in order to determine the value of τ.

[0057] The same principles can be applied to determine the position of an arm 22, such as a crane arm, which extends upwards so that its second end is higher than its rotating axis

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16/19

A '', as illustrated in Figure 7. Again, in this case, the platform tilted through an angle of -τ (that is, τ counterclockwise) in relation to the y axis '', and the arm 22 rotated through an angle of λ (clockwise) around the z axis '', but this time, arm 22 is tilted at an angle of -Omeas (counterclockwise) in relation to the horizontal.

[0058] In this case, the position of the second end of the arm 22 can be determined using the following equations:

Xmeas = sin λ.Σ cos (The ^meas -T) Ymeas = waistband λ.Σ cos (The ^meas -T) Zmeas = h + l sin (The ^meas -T) [0059] The invention is not restricted to use with

a pipe or crane handling device can be used to determine the position of any pivotable part, in relation to platform 11, for example, to determine whether the pivotable part is likely to collide with another fixed or moving part of, or mounted on, the platform.

[0060] It would also be assessed that the length of the arm 22 can be variable, for example if the arm 22 is telescopic. In this case, the system will further comprise means to allow the processor to determine the length of the arm 22, so that the length of the arm 22 can be combined with the corresponding tilt angle at any time, and used as the value l in the above calculations. . For example, where a hydraulic or pneumatic cylinder is used to extend the arm, the system may further comprise a position sensor that is connected to processor 32 and provides an input signal representing the degree of extension of the cylinder. This can be added to the length not

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17/19 extended arm 22 to obtain extended length l.

[0061] The pivotable connection from arm 22 to base 24 can also be movable perpendicular to platform 11. For example, the apparatus for handling the tube or crane can be provided with a winch and wire system that can be used to lift or lower the arm 22 in relation to the base 24. In this case, the system will further comprise means to allow the processor to determine the height of the rotary axis of the arm 22, so that the height rotary axis can be combined with the angle of inclination corresponding to any is used as the h value in the calculations above.

[0062] It will be evaluated that in the examples above, the position of the end of the arm 22 is determined in relation to the x and y axes having its origin defined by the position of the base 24 of the tube manipulator apparatus 20. It is conventional, however, to define locations of the platform 11 of a drilling installation 10 with reference to a point of origin in the center of the well. In order to determine the location of the end of the arm 22 in relation to the center of the well, it would be necessary to combine the x and y coordinates of the origin defined by the base 24 of the tube manipulator apparatus 20 in relation to the center of the well, with the coordinates X ^meas and Y ^meas determined as described above using the first and second slope signs.

[0063] A floating installation can be provided with more than one machine with a pivotable arm, and in order to determine the positions of the end of the pivotable arm of each such machine, it would be necessary to provide a first inclinometer on each pivotable arm. It may not be

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18/19 it is necessary to provide a second inclinometer for each machine. For example, if all pivoting arms pivot on mutually parallel planes, it is possible to use the inclination signal from the same platform 11 or base 24 mounted from inclinometer 30 to determine the angle τ for all arms 22. If, however, arms 22 pivot on planes that are not mutually parallel, it will be necessary to provide a second inclinometer 30 for each machine, each second inclinometer 30 being arranged to measure the inclination of the platform in relation to the horizontal in the direction of its associated arm 22, or to provide a single second inclinometer 30 for all machines which is a biaxial inclinometer, and the processor configured to use the signals from the second biaxial inclinometer 30 to determine a different angle τ for each machine, depending on the orientation of the arm 22 of that machine in relation to the two axes of the second inclinometer 30.

[0064] In the modalities described above, a machine on which a simple single boom arm 22 is shown is shown. It will be appreciated, however, that the invention could also be applied to a machine with a more complex arm, for example, one in which the arm has multiple pivotally connected connections. In this case, if the angle between adjacent connections can be varied, in addition to pivoting the arm 22 around the pivotable connection with the base 24, it would be necessary to provide means to measure the angle of each pivotable connection, and use that information, and the length of each connection, in standard geometric calculations to determine the end position of the arm 22. For example, an inclinometer can be provided for each such connection, and the

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19/19 signal from each of these inclinometers and the second inclinometer 30 used to determine the position of the end of the arm 22.

[0065] An example of such an arrangement is illustrated in Figure 8. In this embodiment, the arm 22 is provided with three connections 22a, 22b and 22c, arranged end to end. Each connection 22a, 22b, 22c is pivotally connected to the connection or adjacent connections, and an inclinometer is mounted on each connection to measure the angle of the connection in relation to the horizontal. Where connections are length la, lb, lc respectively, and platform 11 tilted through an angle of -τ (so counterclockwise), and the inclinometers on each connection 22a, 22b, 22c measure an angle of 0mea ^s1 , gmea ^s 2, _and θ ····· '' respectively, the position of the end of the arm 22 can be calculated using the following equations:

X ^meas = _s i _n λ. (L _a .cos ^ ^meas1 + T) + lb.cos ^ ^meas2 + T) + lc.cos ^ ^meas3 + T)) Y ^meas = cos λ. (La.cos ^ ^meas1 + T) + lb.cos ^ ^meas2 + T) + lc.cos ^ ^meas3 + T)) Z ^meas = h-la.sin ^ ^meas1 + T) -lb.sin ^ ^meas1 + T) -lc. sin ^ ^meas3 + T).

Claims (4)

1. Floating drilling installation, characterized by the fact that it comprises a machine having a base and a pivotable part that is mounted on and pivotable in relation to the base around a rotating axis, and a position measuring device to measure the position from the pivotable part of the machine, the position measuring apparatus comprising a first inclinometer which is mounted on the pivotable part in order to provide a tilt signal representing the absolute angle of inclination of the pivotable part, a second inclinometer which is mounted on the base so to provide a tilt signal representing the absolute tilt angle of the base, and a processor that is connected to the first and second inclinometers in order to receive first and second tilt signals from the first and second inclinometers respectively, and that is programmed to determine the position of the pivotable part of the machine in relation to the base using tan the first as well as the second signs of inclination. 2. Floating drilling installation, according to claim 1, characterized by the fact that the processor is programmed to use information regarding the length of the pivotable part and the height of the pivotable part in relation to the base, and the first and second signs of inclination to determine the location of an end of the pivotable part in relation to the base. 3. Floating drilling installation according to claim 1 or 2, characterized by the fact that the pivotable part comprises an arm having a first end that is mounted on the base, with a tool Petition 870190061966, of 07/03/2019, p. 25/35 2/2 mounted on a second arm end. 4. Floating drilling installation according to claim 3, characterized by the fact that the machine is an apparatus for handling the tube, and the tool comprises a clamp operable to wrap with a tubular element so that the tubular element can be lifted by the arm.