JPH0858696A - Automatic ship position holding system for twin-screw ship - Google Patents

Abstract

PURPOSE: To eliminate the installation of a large steering angle rudder and reduce construction costs by controlling a twin-screw thrust generation device on the basis of a bow bearing deviation value calculated from signals from a bearing sensor and a position sensor, and a longitudinal bearing deviation value of a ship. CONSTITUTION: When a ship's hull bearing remarkably deviates from the direction of external force, the hull is turned in a direction for the action of the external force by the help of an anemoscope/anemometer 29 and a tidal current meter 30. On the other hand, when the hull does not deviate much from the direction of the external force, signals from a bearing sensor 27 as well as a position sensor 28 are immediately inputted to a deviation operation device 32 to calculate a longitudinal bearing deviation value and bearing deviation values fore and aft of the ship. Thereafter, a twin-screw thrust generation device is operated on the basis of the respective deviation values, thereby turning the bow toward an accurate acting direction of the external force. Also, the ship is made to advance whenever necessary, and the position thereof is adjusted, for the ship to arrive at the prescribed position. According to this construction, the hull does not need to be equipped with a special device such as a thruster and a large steering angle rudder, and a ship's construction cost can be greatly reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic position maintaining system for a two-axis ship, and more particularly to an automatic position maintaining system for a two-axis ship suitable for, for example, an oceanographic observation ship.

[0002]

2. Description of the Related Art Generally, for example, in an ocean observation vessel for observing the ocean in a relatively deep sea area, an automatic ship position holding device is provided, and the hull body is held at a predetermined position by the automatic ship position holding device. It is being appreciated. As shown in FIG. 6 (a), this automatic ship position holding device is provided with a propulsion device 2 on a hull 1 and a bow thruster 3 on the bow and a stance thruster 4 on the stern, or as shown in FIG. 6 (b). As shown, the propulsion unit 2 is attached to the stern of the hull 1.
A propulsion shaft 5a, 5b having a and 2b, respectively, and a bow thruster 3a on the bow are used, and as shown in FIG. 7, the signals V ₁ -V ₂ from the position sensor 6 and the direction sensor 7 are used. the input to the central processing unit 8, creating a control signal V ₃ in the central processing unit 8, the control signal V ₄ to input the control signal V ₃ to thrust control apparatus 9
~V ₆ the obtained by controlling the thruster 2 and the bow thruster 3 and stance raster 4 for holding the hull position is performed.

That is, the hull 1 receives an external force such as a tidal current or a wind wave, and is displaced in three directions of a predetermined position in the longitudinal direction X, the lateral direction Y, and the turning angle Z. In order to correct the displacements in these three directions, the position sensor 6 measures the XY displacement amount, and the direction sensor 7 measures the displacement amount of the turning angle Z, and the signal is input to the central processing unit 8 to output a control signal. A control signal of V _{4 to} V ₆ is created, and the thrusters 3 and 4 and the propulsion device 2 are operated by the control signals V _{4 to} V ₆ to operate the hull 1 of FIG.
In this case, as shown in FIGS. 8A to 8F, thrusters Fy ₁ and Fy ₂ by thrusters 3 and 4 and thrust Fx by thruster 2 are applied to correct the position of hull 1. ing.

However, in any of such automatic ship position holding devices, both the bow thruster 3 and the stance thruster 4 or only the bow thruster 3a are arranged on the hull 1 to obtain thrust in the left-right direction of the hull 1. For this reason, the structure becomes complicated because lateral openings must be provided at the bow and stern, and not only does hull resistance increase during normal navigation and fuel consumption declines, but also when using underwater equipment. The cable may get caught. Further, there is a problem that it is difficult to use the underwater equipment due to the noise generated by this thruster.

In order to solve the above problems, 2
A so-called large-angle rudder having a large movable range of a maneuvering rudder of an axial boat has been proposed as an automatic ship-position holding device that holds the ship position by operating this large-angle rudder.

[0006]

By the way, when the large-angle rudder is used, there is a problem that the construction cost becomes high because it is a special device, and it cannot be applied to the existing ships.

[0007]

The present invention has been made in order to solve the problems of the above-mentioned prior art, and has a thrust generating device capable of independently adjusting the thrust in the front-rear direction.
In an axial ship, a) an orientation sensor, a position sensor, a deviation calculation device, a propulsion control force calculation device, and a thrust distribution device are arranged on this two-axis ship, and b) signals of the direction sensor and the position sensor are calculated as the deviation. A first step of inputting to the device to calculate a heading deviation value and a ship front-back deviation value; and c) the heading deviation value and the ship front-rear deviation value to the propulsion control force computing device. A second step of inputting and calculating the required control force, and d) a third step of inputting the required control force to the thrust distribution device and controlling the propulsive force of the biaxial thrust generating device, respectively. It proposes an automatic position-holding method for a two-axis ship.

Preferably, the biaxial ship is provided with an anemometer and a tidal current meter so that the external force acting on the hull and its direction can be detected by the signals obtained from these devices. Then, the signal is used to automatically or manually operate the thrust generators connected to the two axes to turn the hull 1 in advance in the direction in which the external force acts. When the hull is out of a predetermined position after the hull has turned in a predetermined direction, that is, in the direction in which an external force acts, by the automatic ship position holding method, the hull is moved by a biaxial thrust generator by a signal from a position sensor. The ship is maneuvered so that the hull is located at a predetermined position by moving forward.

[0009]

[Operation] According to the automatic position-holding system for the above-mentioned two-axis ship, when the hull is located outside the predetermined position and the direction of the hull greatly deviates from the external force, the wind direction and anemometer and tidal current meter are preliminarily set. And turn the hull in the direction in which the external force acts. On the other hand, when there is no large deviation in the direction of the hull in the direction in which the external force acts, the heading deviation value and the longitudinal deviation value of the ship are immediately calculated by the direction sensor and the position sensor. Based on the deviation value, the two-axis thrust generator is operated to turn the bow in the correct direction of the external force. Then, if necessary, the hull is advanced to correct the position so as to reach a predetermined position.

[0010]

[Embodiment] An embodiment of an automatic position maintaining system for a twin-screw ship according to the present invention will be described below with reference to FIGS. FIG. 1 is a plan view of a hull 21. Propellers 22a and 22b as thrust generating devices are arranged on the hull 21, and the propellers 22a and 22b are attached to the main shafts 23a and 2b.
The main machines 24a and 24b are respectively connected via 3b.

The signal V ₁₁ from the automatic control device 25,
V ₁₂ is given to the main engines 24a and 24b, and the propeller 22
The rotational speeds of a and 22b are adjusted. That is, the thrust can be adjusted. In this case, when the propellers 22a and 22b are composed of variable pitch propellers, the signals V ₁₁ and V ₁₂ from the automatic control device 25 may be input to the blade angle adjusting device of the variable pitch propeller. It should be noted that the rudder 26a, 2 is provided behind the propellers 22a, 22b.
6b are arranged respectively.

As shown in FIG. 2, the automatic control unit 25 is composed of an azimuth sensor 27, a position sensor 28, an anemometer 29, a tide meter 30, and a central processing unit 31 for receiving and processing these signals. Has been done, and this central processing unit 3
1 is composed of a deviation calculation device 32, a propulsion control force calculation device 33, and a thrust distribution device 34. In the case of the hull 21 having two axes having the above-described structure, when the hull 21 is to be held within a radius R centered on the target point [O] (predetermined position) as shown in FIG. When the combined external force P _{3 of} P ₁ and the external force P ₂ due to the tidal current is acting, and further the hull 21 is present at the point X ₁ which is out of the predetermined position, first, the wind anemometer 29 and the tidal current meter 30 The signals V ₁₃ and V ₁₄ are input to the central processing unit 31, and the thrust generators 22a and 22b of the two axes are controlled so that the hull 21 is turned in the direction in which the almost combined external force P ₃ acts and reaches the X ₂ point. Reach

At this time, since accurate control by the signals of the wind direction anemometer 29 and the tidal current meter 30 is practically impossible, as described above, only the turning is performed in the acting direction of the almost combined external force P ₃ . Thereafter, as shown in FIG. 4, the azimuth deviation value [θ] from the combined external force P ₃ is detected by the signal V ₁₅ of the direction sensor 27 and the deviation calculation device 32, and the deviation value in the longitudinal direction of the ship from the predetermined position [θ]. [alpha]] is calculated by the signal V ₁₆ from the position sensor 28 and the deviation calculation device 32 (first step).

Next, the heading deviation value [θ] and the longitudinal deviation value [α] of the ship are input to the propulsion control force calculation device 33,
These bearing deviations [θ] and ship deviations [α]
The required control force such that and are zero, that is, the front-rear direction control force Fx of the hull 21 and the turning direction control force M are calculated (second
Process). That is, as shown in FIG. 5, a propeller 22a from the center line of the thrust · · · F ₂ and the hull 21 of the thrust · · · F ₁ propeller 22b of the propeller 22a, 22b
When the distance to the [a] _{is, Fx = F 1 + F 2} , Fy = 0, M = 2 × F 1 - "necessary control force" from the relationship a × F ₂ is calculated, the result Is input to the thrust distribution device 34. And the propeller 22a,
The command thrusts F ₁ and F _{2 of} 22b are calculated. That is, the command thrusts F ₁ and F ₂ are calculated as F ₁ = (aFx−M) / 2a, F ₂ = (aFx + M) / 2a (third third).
Process).

During such automatic control, the hull 21 is displaced from the X ₂ point to the X ₆ point by the action of the combined external force P ₃ as shown in FIG. 3 and the bow is accurately turned in the combined external force P ₃ direction. become. Thereafter, only the deviation value [α] in the front-rear direction of the hull 21 is input to the arithmetic unit 33, and the propeller 22
The thrusts F ₁ and F ₂ of a and 22b become equal, and the hull 21 advances to reach a predetermined position.

Of course, when the bow of the hull 21 is located in a direction approximately equal to the combined external force P ₃ , the signals V ₁₃ and V ₁₄ of the wind direction anemometer 29 and the tidal current meter 30 can be ignored. Therefore, maneuvering becomes significantly easier.

[0017]

As is clear from the above description, the following effects can be achieved by the automatic position-holding system for a twin-screw ship according to the present invention. B) It is not necessary to equip the hull with special equipment such as thrusters and large-angle rudder, and it is possible to maintain the position as long as the propeller with two axes is equipped, so the construction cost can be greatly reduced. .

(B) Since the hull can be turned accurately against the combined external force without relying on the signals of the wind direction and anemometer, which are relatively unreliable, the device is inexpensive and the accurate automatic position maintenance is possible. Is. C) Since the bow is directed in the direction of the combined external force, there is almost no need to generate a turning moment, and the thrust that can be generated by the two-axis propeller is the position-holding limit external force, which was previously impossible due to insufficient thrust. Position can be maintained even in high sea conditions. D) Since there is no need to modify the hull, it can be easily applied to existing ships.

[Brief description of drawings]

FIG. 1 is a plan view showing the concept of a biaxial ship according to the present invention.

FIG. 2 is a system diagram of an automatic control device.

FIG. 3 is an explanatory view of the operation of the present invention.

FIG. 4 is an explanatory view of the operation of the present invention.

FIG. 5 is an explanatory diagram of control of a hull according to the present invention.

6 (a) and 6 (b) are explanatory views of the concept of a conventional automatic position maintaining system.

FIG. 7 is a system diagram of a conventional automatic control system of an automatic ship position holding system.

8 (a) to 8 (f) are explanatory views of a conventional automatic ship-position-holding operation method.

[Explanation of symbols]

1,21 Hull 2 Propulsor 3 Bow thruster 4 Stancer 5a, 5b Propulsion axis 6,28 Position sensor 7,27 Direction sensor 8,31 Central processing unit 9 Thrust control device 22a, 22b
Propellers 23a, 23b Spindles 24a, 24b
Main machine 25 Automatic control device 26a, 26b
Rudder 29 Wind direction anemometer 30 Tidal current meter 32 Deviation calculation device 33 Propulsion control force calculation device 34 Thrust distribution device

Claims (1)

[Claims] 1. A two-axis ship having thrust generators capable of independently adjusting forward and backward thrusts, wherein an orientation sensor, a position sensor, a deviation calculation device, and a propulsion control force calculation device are provided in the two-axis ship. A thrust distribution device is arranged, and signals from the direction sensor and the position sensor are input to the deviation calculation device to calculate a bow direction deviation value and a longitudinal deviation value of the ship.
And a second step of calculating the required control force by inputting the heading deviation value and the longitudinal deviation value of the ship to the propulsion control force calculation device, and the necessary control force to the thrust distribution device. An automatic position-holding system for a two-axis ship, which comprises a third step of inputting and controlling the propulsive forces of the two-axis thrust generators, respectively.