JPH03220089A - Spar buoy type working scaffolding - Google Patents

Abstract

PURPOSE:To facilitate the arrangement for temporary installation transfer, removal, and the depth of water and permit the use at a place where tidal power, etc. is large, by keeping a pillar body at a vertical state by controlling a thrust generator installed on the pillar body or buoyancy body by the attitude detection signal of the pillar body, in the title scaffolding for the investigation for the geological features such as sea bottom. CONSTITUTION:An accelerating speedometer for two horizontal components is installed as an attitude detector 24, at the positions of the diagonal lines of a square-shaped working board 12, and a screw propeller type thrust generator 26 for controlling attitude which generates each thrust in two horizontal directions is installed on a buoyancy body 14. The attitude of a pillar body 10 is detected by the attitude detector 24, and the thrust generator 26 is controlled on the basis of the signal of the attitude detector 24, and the vertical attitude of the pillar body 10 is maintained. With this constitution, and arrangement for the temporary installation, transfer, removal and the depth of water is facilitated, and the use of the title device is permitted at a place where tidal power and wave force are large.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a retractable and moored superbuoy-type work scaffold suitable for geological surveys of the seabed, lakebed, riverbed, etc., poling work, etc.

[Prior Art] Various types of work scaffolds are swept and used for geological surveys of the seabed, etc., poling work, etc. Broadly speaking, these types of scaffolding include fixed scaffolding, which uses trenches etc. driven into the seabed and a work platform fixed to them as scaffolding, stationary scaffolding, which installs turrets etc. on the seabed, and floating scaffolding, which anchors floating bodies, ships, etc. be.

Although the fixed method is suitable for long-term surveys, it has the disadvantage that it cannot be moved, and the tower installation method is difficult to apply to deep water and is difficult to move. In contrast, the floating method is superior in terms of mobility.

By comprehensively considering the advantages and disadvantages of these conventional technologies, a pull-in mooring type super buoy system was devised as a type of levitation system. This is based on the fact that the retractable mooring type spar buoy, which has traditionally been used for buoys such as navigation aids, is stable in an upright position with little tilting due to wind and waves, and is relatively easy to move. The workbench will be used as a scaffold.

[Problems to be Solved by the Invention] Such a spar buoy-type work scaffold is particularly promising because it can be used at great depths, is economical, and is easy to move without requiring mooring cables. However, it is impossible to completely ignore the oscillation caused by waves with a period close to the natural period of the scaffold and the rotation of the scaffold as a reaction to Rondo rotation during poling work.

In addition, it is considered difficult to use in areas such as areas outside the bay where the waves are high and cause a great deal of turbulence during stormy weather.

The purpose of the present invention is to solve the above-mentioned technical problems, take advantage of the characteristics of the super buoy system, which has a simple structure, is easy to temporarily install, relocate, and remove, and can easily handle different water depths. To provide a super buoy-type work scaffold that can be used even in places where tidal and wave power are large, such as in the United States, and which can minimize sway even in rough weather and improve operating efficiency.

[Means for solving the problem] The present invention provides a workbench at the top of a column, a buoyant body in the middle,
This is an improved super buoy type work scaffold in which the lower end of the column is moored to a sinker using a mooring mechanism to draw the buoyant body into the water so that the water line is located midway through the column above the buoyant body. In order to achieve the above object, the present invention includes a columnar attitude detector, a thrust generating device for attitude control provided on the columnar body or a buoyant body, and a columnar body that is always approximately aligned based on a signal from the attitude detector. and an attitude control device that controls the thrust generating device to maintain the upright state.

Here, a fuzzy controller is built into the attitude control device, a disturbance detector is installed that detects one or more of disturbances such as tidal power, wind power, wave force, etc., and the attitude control device uses the fuzzy (It is preferable to perform this and control the column to stabilize it in an upright position.)

The work scaffold of the present invention is suitable for, for example, boring link work, in which case a center pipe for inserting a boring rod that runs through the entire device is provided. Then, it is necessary to detect the reaction force during polling work and use it as one of the inputs for fuzzy inference to perform a control that suppresses the rotation of the work scaffold.

[Function] Super buoy-type work scaffolding originally has the property of being stable in an upright position with little tilting or sway due to water currents or wind waves. However, during stormy weather, for example, considerable turbulence can occur within the bay. In addition, when installing outside the bay, tidal power, wind power,
It tilts or sways significantly due to wave force, etc.

In the present invention, the posture detector detects the displacement of the column from the upright state, and based on this, the posture is adjusted. The Il device operates the thrust generating device to perform stabilization control so that the column always maintains a substantially upright state. This eliminates inconveniences such as restrictions on installation locations and inability to perform work due to bad weather.

In particular, various detectors are installed to detect tidal power, wind power, wave power, etc.
By performing fuzzy inference using these signals, more stable and smooth control becomes possible.

[Example] Fig. 1 is an overall configuration diagram showing one embodiment of a super buoy-type work scaffold according to the present invention. A buoyant body 14 is provided, and the lower end of the column 10 is moored to a sinker 18 by a mooring mechanism 16 to draw the buoyant body 14 into the water, so that the water line 17 is located midway through the column above the buoyant body 14. It is something. The mooring mechanism 16 here is a cross-parallel chain type, and a circular ring 20 is provided between the lower end of the column 10 and the sinker 18, and the connections between the column IO and the sinker 18 are connected via this ring. It is moored with two chains 22 so as to be perpendicular to each other, and is moored in a horizontal plane with respect to the inclination of the column 10.
It has a degree of freedom in the 0 degree direction.

FIG. 2 depicts the mooring mechanism 16 from a direction 90 degrees different from FIG. 1.

Now, the present invention provides such a super buoy type work scaffold with a device for stably maintaining its upright posture. In this embodiment, as shown in FIGS. 3A and 3B, a horizontal two-component accelerometer (
For example, a servo accelerometer) is attached as the attitude detector 24. Further, as shown in FIG. 4, the buoyant body 14 is provided with a screw propeller type thrust generating device 26 for attitude control that generates thrust in two horizontal directions. Instead of the screw propeller type, a Schneiter propeller or water jet type thrust generator may be used. Based on the signal from the attitude detector 24, the thrust generator 26 is controlled by the attitude control device so that the column 10 always maintains a substantially upright state. This control may be normal feedback control, or may be a method in which the control thrust and its direction are set by fuzzy reasoning, taking into account other measurement items.

In the embodiment shown in FIG. 1, a workbench 1 is used as a disturbance detector.
2, and a tidal current direction and current meter 30 and wave height meter 32 provided above the buoyant body 14.

This spar buoy type work scaffold is particularly suitable for geological surveys of seabeds and lake beds, poling work, etc. For poling work, as shown in FIG. A center pipe will be provided for the insertion of the boring rod.

In that case, install a polling machine on the workbench 12! However, this operation applies a reaction force to the workbench 12, causing unnecessary rotation.

The magnitude of the reaction force can be determined from the load applied to the polling machine.

The spar buoy type work scaffold supports the work platform 1 by strong tension generated between the column 10, the buoyant body 14, and the sinker 18.
2 maintains a stable posture at a single point on the water. However, this alone cannot completely prevent tilting and shaking caused by wave, wind, and water power. An example of the relationship between wind and tidal forces and the inclination angle of the work scaffold is shown in Figure 5. Even if the tidal current is about 1 noa), if the wind speed is 10 m/sec or less, the inclination angle will be within 1.6 degrees. Figure 6 shows the oscillation characteristics during waves. This can be expressed as a correlation between wave height and wave period; even if the wave height is constant, as the wave period increases, the inclination angle increases. For example, wave height 1m'?
:'When the cycle is 6 seconds, the maximum swing angle is about 0.4 degrees. FIG. 7 shows a state in which these conditions are combined. The angle of inclination of the work scaffold is approximately 2 degrees due to the combination of the inclination caused by wind and tidal power and the sway caused by wave force. The maximum allowable inclination angle varies depending on the type of work and work content. If you want to manually take a soil sample that will not be disturbed by polling or the like, the angle of inclination must be made as small as possible.

Therefore, it is more preferable to perform control as shown in a block diagram as shown in FIG. Attitude control with a built-in fuzzy controller that uses the attitude detection signal obtained from the attitude detector 24 such as an accelerometer as the main input, and inputs the direction and velocity of the current, the direction and speed of the wind, the wave height and period, and the work reaction force, etc. The device 40 performs fuzzy inference. Then, the optimal control thrust and its direction are determined using data on the influence of various disturbances as shown in FIGS. 5 and 6, which have been obtained in advance, and the thrust generator 26 is driven. In this way, fuzzy reasoning is most applicable to the control of work scaffolding as in the present invention.

In the case of a screw propeller type, direction control may be performed by changing the direction of the propeller itself, or it is also possible to combine it with a stabilizing plate or the like for direction control.

These control the tilting, wobbling, and rotation of the workbench, and maintain the column in an upright and stable state.

[Effects of the Invention] Since the present invention is a retractable mooring spar buoy type work scaffold as described above, mooring lines are not required, the water area occupied during work can be minimized, and ships can pass near the scaffold. It has the following advantages: it has a simple structure, does not require a work barge during polling work, is easy to temporarily install, relocate, and remove, and can freely respond to changes in water depth by adding columns.

In addition, the present invention detects the attitude and drives the thrust generator accordingly to control the column so that it always maintains an upright state, so it can be used unless the weather is extremely rough, and it can also be used outside the bay. It has the effect of being able to be installed in areas with strong currents and waves to perform various types of work. Furthermore, even when installed in a bay, it is possible to control the upright and stabilized posture, improving work efficiency and making it possible to collect high-quality soil samples that are not disturbed by polling.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing one embodiment of a super buoy type work scaffold according to the present invention, Fig. 2 is an explanatory diagram of the mooring m structure seen from a 90 degree different direction, and Fig. 3 A is an enlarged view of the work platform. B is a front view, B is a plan view thereof, and FIG. 4 is an enlarged explanatory view of the buoyant body and its vicinity. Figure 5 is a graph showing the slope characteristics during uncontrolled wind and tidal current, Figure 6 is a graph showing the oscillation characteristics in waves when uncontrolled, and Figure 7 is the overall uncontrolled condition during rough weather. FIG. FIG. 8 is a block diagram of the control system. DESCRIPTION OF SYMBOLS 10... Column body, 12... Workbench, 14... Buoyancy body, 16... Mooring mechanism, 18... Sinking weight, 24... Attitude detector, 25... Thrust generator , 28... Wind direction and speed meter, 30... Current direction and current velocity meter, 32... Wave height meter.

Claims (1)

[Claims] 1. A workbench is provided at the top of the column, a buoyant body is provided in the middle, the lower end of the column is moored to a sinker by a mooring mechanism, and the buoyant body is drawn into the water, so that the water line is above the buoyant body. In a super buoy-type work scaffold that is placed in the middle of the column, the posture detector of the column and
a thrust generator for attitude control provided on the column or buoyant body;
A super buoy type work scaffold comprising: an attitude control device that controls the thrust generator so that the column always maintains a substantially upright state based on a signal from the attitude detector. 2. It has a disturbance detector that detects one or more of tidal power, wind power, and wave power, and the attitude control device is equipped with a fuzzy controller, and the attitude control device performs fuzzy inference by taking into account the signals from the detector. 2. The work scaffold according to claim 1, wherein the column is stabilized in an upright position. 3. A center pipe for penetrating a boring rod that penetrates the column, buoyant body, and sinker, has a lower end that reaches the lower surface of the sinker and opens at the bottom of the water, and an upper end that reaches above the water line.
Or the work scaffold described in 2. 4. The work scaffold according to claim 2, wherein the work reaction force is detected and is one of the inputs to the fuzzy controller.