JP2006297999A - Fin stabilizer for vessel, its controlling method and controlling program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a swing of a hull with high precision by generating a lift as desired. <P>SOLUTION: The torque of a fin 11 is calculated by a torque calculation part 27 on the basis of the pressure of a hydraulic cylinder 12. The torque obtained is fed to an attack angle calculation part 24 through a torque adjuster 28, and on the basis of the fed torque, the angle of the fin with respect to the flow of sea water, i.e. the attack angle of the fin, is presumed. A command producing part 23 produces a fin angle command value θ3 for putting the presumed attack angle θ2' identical to the target fin angle θ1, and the angle of the fin 11 is adjusted by controlling the flow rate Q of a working oil given to the hydraulic cylinder 12 from a flow rate adjusting mechanism 14 on the basis of the fin angle command value θ3. The desired lift is obtained in this manner, by controlling the fin angle on the basis of the attack angle whereto the lift is related directly, and the accuracy of the swing decreasing control is enhanced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a ship fin stabilizer for suppressing the hulling of a hull.

Conventionally, for example, a fin stabilizer is known as a device that suppresses a roll motion or a pitch motion of a ship (see, for example, JP-A-8-324485). This fin stabilizer is provided with fins protruding from the hull outer plate, and controls the inclination of the fins to generate lift and suppress rolling of the hull.
In such a fin stabilizer, the angle of the fin with respect to the flow of seawater (hereinafter referred to as “attack angle”) and the angle of the fin with respect to the hull (hereinafter referred to as “fin angle”) are considered to be the same. Accordingly, the hull vibration reduction control is performed by controlling the fin angle.
JP-A-8-324485 (page 2-3, FIG. 3)

  However, the angle of attack and the fin angle may not match due to the influence of disturbance due to waves and hull motion. In such a case, the conventional fin stabilizer described above has a problem that the fin angle cannot be controlled to an appropriate angle, and a desired lift for suppressing the hull sway cannot be obtained.

  The present invention has been made to solve the above problem, and provides a ship fin stabilizer, a control method therefor, and a control program that can suppress the shaking of the hull with high accuracy by obtaining a desired lift. For the purpose.

In order to solve the above problems, the present invention employs the following means.
The present invention is a marine fin stabilizer comprising a fin attached to a hull to reduce the fluctuation of the hull, and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull. Pressure detecting means for detecting the pressure of the hydraulic cylinder; torque calculating means for calculating the torque of the fin based on the pressure; and fin angle estimation for estimating the angle of the fin with respect to the flow of seawater based on the torque. Means for generating a fin angle command for matching the estimated angle of the fin with a target angle for canceling the shaking of the hull, and the fin driving device includes the fin angle command. The ship fin stabilizer which drives the said fin based on this is provided.

According to the above configuration, the torque of the fin is calculated based on the pressure of the hydraulic cylinder by the torque calculating means, and the angle of the fin with respect to the seawater flow, that is, the angle of attack, is calculated based on the torque by the fin angle estimating means. Is estimated. The command generation means generates a fin angle command value for making the angle of attack coincide with the target angle, and the fin driving device drives the fin based on the fin angle command value. In this way, by controlling the fin angle based on the angle of attack directly related to lift, it is possible to obtain a desired lift and improve the accuracy of the vibration reduction control.
Here, there is a correlation between the lift acting on the fin and the torque of the fin. Further, the torque of the fin has a correlation with the pressure of the hydraulic cylinder. Therefore, the torque of the fin can be obtained from the pressure of the hydraulic cylinder, and the lift acting on the fin can be obtained from this torque. Furthermore, since the lift acting on the fin is determined by the angle of attack of the fin, the angle of attack of the fin can be estimated from the torque of the fin.

  The ship fin stabilizer described above further includes fin angle detection means for detecting an angle of the fin with respect to the hull, and the command generation means has a swing period of the hull that is equal to or less than a predetermined threshold value. In this case, it is preferable to generate a fin angle command for causing the fin angle detected by the fin angle detecting means to coincide with the target angle.

  When the oscillation period is equal to or less than the predetermined period, the accuracy of torque calculation is reduced due to a decrease in the accuracy of pressure detection by the pressure detection means. As a result, the reliability of the fin angle estimated by the fin angle estimation means is reduced. May be low. In such a case, the vibration reduction control based on the fin angle with respect to the hull is performed to maintain the same level of accuracy as in the past.

  In the ship fin stabilizer described above, the pressure detection means includes a pressure sensor that detects pressures in the upper cylinder chamber and the lower cylinder chamber of the hydraulic cylinder, and noise included in a detection value detected by the pressure sensor. Noise removal means for removing components, and the predetermined threshold value may be determined based on the performance of the noise removal means.

  The performance of the noise removing means changes according to the oscillation period. Therefore, in the region where the performance of the noise removing means is reduced, that is, when the oscillation period is such that the required pressure detection accuracy cannot be maintained, the above-described vibration reduction control based on the fin angle with respect to the hull is performed. It is said.

  In the ship fin stabilizer described above, the fin angle detection means for detecting the angle of the fin with respect to the hull, the angle of the fin with respect to the flow of seawater estimated by the fin angle estimation means, and the fin angle detection means Difference calculating means for obtaining a difference between the detected angle of the fin and the hull, and the command generating means detects the fin angle when the difference is equal to or greater than a predetermined value. A fin angle command for matching the angle of the fin with respect to the hull detected by the means to the target angle may be generated.

  According to the above configuration, the difference between the fin angle detected by the fin angle detection means, that is, the fin angle, and the fin angle estimated by the fin angle estimation means, that is, the attack angle is obtained by the difference calculation means. When the difference is greater than or equal to a predetermined value set in advance, the command generation means generates a fin angle command based on the fin angle. As described above, when the error between the two is large, the control is stabilized by performing the fin control based on the fin angle instead of the angle of attack.

  The present invention is a control method for a ship fin stabilizer that includes a fin attached to a hull to reduce the fluctuation of the hull and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull. The process of calculating the torque of the fin based on the pressure of the hydraulic cylinder, the process of estimating the angle of the fin with respect to the flow of seawater based on the torque, and the estimated angle of the fin as the hull Provided is a method for controlling a fin stabilizer for a ship, comprising: a step of generating a fin angle command for matching a target angle for canceling the fluctuation of the ship; and a step of controlling the fin driving device based on the fin angle command. To do.

  According to the above control method, the torque of the fin is calculated based on the pressure of the hydraulic cylinder, and the angle of the fin with respect to the flow of seawater, that is, the angle of attack directly related to the lift force is estimated based on this torque. The Then, a fin angle command value for making the angle of attack coincide with the target angle is generated, and the fin driving device drives the fin based on the fin angle command value. This makes it possible to obtain a desired lift and improve the accuracy of the vibration reduction control.

  The present invention controls a marine fin stabilizer including a fin attached to a hull to reduce the fluctuation of the hull and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull. And a step of calculating a torque of the fin based on the pressure of the hydraulic cylinder, a step of estimating an angle of the fin with respect to a seawater flow based on the torque, and the estimated fin Generating a fin angle command for matching the angle of the fin to a target angle for canceling the shaking of the hull, and causing the computer to execute a step of controlling the fin driving device based on the fin angle command Provide a control program.

  By executing the control program by the computer, the torque of the fin is calculated based on the pressure of the hydraulic cylinder, and based on this torque, the angle of the fin with respect to the flow of seawater, that is, directly related to the lift force. The angle of attack is estimated. Then, a fin angle command value for making the angle of attack coincide with the target angle is generated, and the fin driving device drives the fin based on the fin angle command value. This makes it possible to obtain a desired lift and improve the accuracy of the vibration reduction control.

  According to the marine fin stabilizer of the present invention, its control method, and control program, it is possible to obtain a desired lift, so that it is possible to suppress the fluctuation of the hull with high accuracy.

  Hereinafter, embodiments of a ship fin stabilizer according to the present invention will be described in the order of [first embodiment] and [second embodiment] with reference to the drawings.

[First Embodiment]
Hereinafter, the marine fin stabilizer according to the first embodiment of the present invention will be described.
FIG. 1 is a control block diagram for explaining the action of a ship fin stabilizer (hereinafter referred to as “fin stabilizer”) according to the present embodiment on a hull.
As shown in this figure, the actual inclination angle φ of the hull 2 is detected by a sensor (not shown) provided in the hull 2 and input to the target inclination angle generation unit 50. In the target inclination angle generation unit 50, an inclination angle command φ ′ for making the actual inclination angle φ of the hull 2 coincide with the target inclination angle φref (= 0) is calculated, and this inclination angle command φ ′ is output to the fin stabilizer 1. Is done. The target inclination angle generation unit 50 outputs, for example, a difference between the target inclination angle φref and the actual inclination angle φ of the hull 2 as an inclination angle command φ ′. In the fin stabilizer 1, as will be described later, by controlling the angle of the fin based on the tilt angle command φ ′, lift is generated so as to make the tilt angle of the hull 2 zero, and the swing of the hull 2 is suppressed. To do.

As shown in FIG. 2, the fin stabilizer 1 is configured such that the fin 11 is swung around a rocking axis by a hydraulic cylinder 12. The hydraulic cylinder 12 can be operated in two reciprocating directions according to the flow rate Q in the positive and negative directions of hydraulic oil supplied from a constant discharge pump via a flow rate adjusting mechanism 14 (for example, including an electrohydraulic servo valve). The piston P is provided. The flow rate Q of the discharged oil is adjusted by the flow rate adjusting mechanism 14.
With such a configuration, when the flow rate Q is adjusted by the flow rate adjusting mechanism 14, the piston P of the hydraulic cylinder 12 moves in the vertical direction, and the angle θ of the fin 11 is adjusted to a desired angle.

  The upper cylinder chamber 12a of the hydraulic cylinder 12 is provided with an upper pressure sensor 16a for detecting the hydraulic pressure in the cylinder. Similarly, the lower cylinder chamber 12b of the hydraulic cylinder 12 is provided with a lower pressure sensor 16b that detects the hydraulic pressure in the cylinder.

  Next, the control system of the fin stabilizer according to this embodiment described above will be described with reference to FIG. FIG. 3 is a block diagram showing a control system of the fin stabilizer according to the present embodiment. 3, the same components as those shown in FIG. 2 described above are denoted by the same reference numerals.

  First, the tilt command value φ ′ shown in FIG. 1 is directly inputted to the fuzzy computing unit 21 of the fin stabilizer 1 shown in FIG. 3, and a part thereof is differentiated by the differentiator 22 and inputted to the fuzzy computing unit 21. The Based on the input information, the fuzzy computing unit 21 obtains a fin angle required to make the inclination angle φ of the hull 2 zero, and outputs this as the target fin angle θ1. In addition, about the calculation procedure performed in the fuzzy calculator 21, it is good to employ | adopt the method currently disclosed by patent 2915658, for example.

  The target fin angle θ1 output from the fuzzy calculator 21 is input to the command generation unit 23. The command generation unit 23 and the target fin angle θ1 and the angle of attack of the fin estimated by the angle-of-attack calculating unit 24 (to be described later) (hereinafter referred to as “estimated angle of attack”). Is compared with θ2 ′ to obtain a fin angle command value θ3 for making the estimated attack angle θ2 ′ of the fin 11 coincide with the target fin angle θ1.

  The fin angle command value θ3 obtained by the command control unit 23 is input to the flow rate adjusting mechanism 14. The flow rate adjusting mechanism 14 operates to supply hydraulic oil with a flow rate Q corresponding to the fin angle command value θ3 to the hydraulic cylinder 12. Thereby, the flow rate Q corresponding to the fin angle command value θ3 is supplied to the hydraulic cylinder 12, and the actual fin angle of the fin 11 (hereinafter referred to as “actual fin angle”. The fin angle is the angle of the fin 11 with respect to the hull. .Theta.3 'changes. By changing the fin angle θ3 ′ due to the influence of disturbance W such as seawater, the fin angle with respect to the seawater, that is, the actual fin attack angle θ2, and the lift according to the actual fin attack angle θ2 acts. Hulling is suppressed.

  On the other hand, in order to feedback control the actual fin attack angle θ2, first, the pressure in the upper cylinder chamber of the hydraulic cylinder 12 is detected by the upper pressure sensor 16a, and the pressure in the lower cylinder chamber is detected by the lower pressure sensor 16b. Is done. These detected values pass through the low-pass filter 25 to remove harmonics (noise components) and are input to the subtractor 26. In the subtractor 26, the pressure difference between the upper and lower cylinder chambers of the hydraulic cylinder 12 is calculated, and the pressure difference as the calculation result is input to the torque calculation unit 27. The torque calculator 27 calculates the torque acting on the fin 11 based on the pressure difference between the upper and lower cylinder chambers of the hydraulic cylinder 12 and outputs this torque. The torque calculated by the torque calculation unit 27 is input to the angle-of-attack calculation unit 24 after the torque adjuster 28 subtracts the weight torque corresponding to the torque due to the weight of the fin.

The angle of attack calculation unit 24 estimates the angle of attack θ2 of the fin 11 based on the torque input from the torque adjuster 28.
For example, as shown in FIG. 4, the angle-of-attack calculation unit 24 has a moment coefficient table that associates the moment coefficient Cm related to the moment M acting on the fin 11 with the angle of attack θ2. Here, since the relationship between the moment coefficient Cm and the angle of attack θ2 varies depending on the flow velocity v of the seawater, these are associated with each other according to the seawater.

Here, the moment coefficient Cm can be obtained by the following equation (1).

Here, various parameters used in the above equation (1) will be described with reference to FIG. FIG. 5 is a longitudinal sectional view of the fin 11 and is a diagram for explaining the force acting on the fin 11. In this figure, the traveling direction of the hull 2 is indicated by an arrow G.
In the above equation (1), the parameter M is a moment acting on the fin 11 as shown in FIG. 5, and in this embodiment, the torque of the fin 11 input to the angle-of-attack calculating unit 24 as this moment M. Is adopted. The parameter ρ is the density of seawater, and for example, 1025 kg / m ³ is used. The parameter v is the flow velocity of seawater, and in this embodiment, the ship speed is adopted. In addition, the direction of the flow rate of seawater and the direction of ship speed are opposite directions as shown in FIG. The parameter A is the surface area of the fin 11. For example, an example of the surface area is shown as a square in the upper part of FIG. The parameter C is the length of the fin 11 with respect to the direction of the seawater flow. Of the various parameters described above, parameters ρ, A, and C are all registered in advance as constants, and parameters v and M are values that reflect real-time ship speed and torque.

When the torque is input from the torque adjuster 28, the angle-of-attack calculation unit 24 inputs the torque as a parameter M to the above (1), and inputs the ship speed v at this time to the above formula (1), A moment coefficient Cm is calculated. Then, the angle-of-attack calculation unit 24 acquires the angle of attack θ2 corresponding to the moment coefficient Cm and the ship speed v from the moment coefficient table shown in FIG. In this manner, when the attack angle calculation unit 24 acquires the current attack angle θ2 of the fin 11, the attack angle θ2 is output as an estimated attack angle, that is, an estimated attack angle θ2 ′.
The estimated attack angle θ2 ′ is fed back to the command control unit 23 shown in FIG.

  Then, the command generation unit 23 calculates a fin angle command value θ3 for making the estimated angle of attack θ2 ′ fed back from the angle of attack calculation unit 24 coincide with the target fin angle θ1 input from the fuzzy calculator 21; By outputting the fin angle command value to the inflow adjusting mechanism 14, the fin angle is adjusted based on the fin angle command value θ3. As a result, the actual attack angle θ2 of the fin 11 is made to coincide with the target fin angle θ1. It becomes possible. As a result, a desired lift F can be generated by the action of the fins 11, thereby suppressing the shaking of the hull 2.

  As described above, according to the fin stabilizer according to the present embodiment, the angle of the fin after various disturbances W such as ocean currents, that is, the angle of attack is estimated, and based on the estimated angle of attack θ2 ′. Since the feedback control of the fin angle is performed, it is possible to eliminate the lift reduction due to the disturbance W and to improve the accuracy of the vibration reduction control.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
The fin stabilizer of the present embodiment is different from the first embodiment in that a predetermined condition is added in the feedback system, and the angle of the fin to be fed back is estimated angle of attack θ2 ′ or actual fin angle θ3 according to this condition. It is a point to switch to '.
For example, the difference between the estimated angle of attack θ2 ′ and the actual fin angle θ3 ′ is a predetermined value (for example, 2 °) or less, and the oscillation cycle of the hull 2 (see FIG. 1) is set in advance. When it is equal to or greater than a threshold (for example, 20 seconds), the estimated attack angle θ2 ′ is fed back.
On the other hand, when the above condition is not satisfied, that is, when the difference between the estimated attack angle θ2 ′ and the actual fin angle θ3 ′ exceeds a predetermined value (for example, 2 °), or the hull 2 (see FIG. 1) ) Is not more than a predetermined threshold value (for example, 20 seconds) set in advance, the actual fin angle θ3 ′ is fed back instead of the estimated angle of attack.

For example, when the hull oscillation period is short, it is difficult to remove harmonics contained in the sensor outputs from the pressure sensors 16a and 16b by the low-pass filter 25. Therefore, in the present embodiment, in the region where the pressure in the upper and lower cylinder chambers of the hydraulic cylinder cannot be detected with high accuracy, feedback control based on the actual fin angle θ3 ′ is performed instead of the estimated attack angle θ2 ′. For this reason, for example, the predetermined threshold value in the above condition is determined by the performance of the low-pass filter.
In addition, when the estimated attack angle θ2 ′ is too different from the actual fin angle θ3 ′, there may be a factor such as a failure of the pressure sensor, and the control stability may be reduced. Then, only when the difference between the two angles is within a predetermined value, the estimated angle of attack θ2 ′ is fed back to maintain control stability.

  Next, an example of a specific configuration of the marine fin stabilizer according to the present embodiment will be described with reference to the drawings. FIG. 6 is a diagram illustrating a control system of the fin stabilizer according to the present embodiment. In FIG. 6, the same components as those shown in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted.

In the fin stabilizer control system according to the first embodiment shown in FIG. 3, the fin stabilizer according to the present embodiment includes a subtracter 30 and a limiter in a feedback line connecting the angle-of-attack calculation unit 24 and the command generation unit 23. 31 and a switch 32 are provided.
First, the estimated angle-of-attack θ2 ′ estimated by the angle-of-attack calculator 24 is input to the subtractor 30, and the subtractor 30 calculates a difference from the actual fin angle θ3 ′. The actual fin angle θ3 ′ is detected by a known technique, and the actual fin angle θ3 ′ detected by a known technique may be used.
The difference θ2′−θ3 ′ calculated by the subtracter 30 is input to the limiter 31. The limiter 31 compares whether or not the difference θ2′−θ3 ′ is a predetermined value (for example, 2 °) or less, and if the difference is equal to or smaller than the predetermined value, outputs the difference to the switch 32 and the difference is predetermined. If the value is exceeded, “zero” is output to the switch 32.

  Subsequently, the switch 32 is a switch that is switched in accordance with the shaking cycle of the hull 2. When the shaking cycle of the hull 2 is larger than a predetermined threshold, the difference input from the limiter 31 is used as the command generator 23. Is output to the first subtractor 23a included in the. On the other hand, when the oscillation cycle of the hull 2 is equal to or less than a predetermined threshold, the switch 32 outputs “zero” to the command generation unit 23.

  As a result, when the difference between the estimated attack angle θ2 ′ and the actual fin angle θ3 ′ is equal to or less than a predetermined value (for example, 2 °) and the oscillation period of the hull 2 is equal to or greater than the threshold value, the subtractor The difference θ2′−θ3 ′ calculated by 32 is fed back to the first subtractor 23a of the command generator 23. The first subtractor 23a of the command generation unit 23 has a difference θ1− (θ2′−θ3) between the difference θ2′−θ3 ′ input from the switch 32 and the target fin angle θ1 input from the fuzzy calculator 21. ′) Is calculated, and the calculation result is output to the second subtractor 23 b included in the command generation unit 23. The second subtractor 23b is the difference between the difference θ1− (θ2′−θ3 ′) input from the first subtractor 23a and the actual fin angle θ3 ′, that is, θ1− (θ2′−θ3 ′) −. θ3 ′ = θ1−θ2 ′ is calculated, and the calculation result θ1−θ2 ′ is output to the flow rate adjusting mechanism 14 as the fin angle command value θ3. That is, in this case, the angle of the fin to be fed back becomes the estimated angle of attack θ2 ′.

  On the other hand, if the difference between the estimated attack angle θ2 ′ and the actual fin angle θ3 ′ exceeds a predetermined value (for example, 2 °), or if the hull period of the hull 2 is less than the threshold value, The signal fed back to the first subtractor 23a of the generation unit 23 is “zero”. As a result, the calculation result of the first subtractor 23a of the command generating unit 23 is θ1-0 = θ1, and the target fin angle θ1 is input to the second subtractor 23b. In the second subtractor, the difference between the target fin angle θ1 and the actual fin angle θ3 ′, that is, θ1-θ3 ′ is calculated, and the calculation result θ1-θ3 ′ is used as the fin angle command value θ3. Output to. That is, in this case, the angle of the fin to be fed back is the actual fin angle θ3 ′.

  As a result, the difference between the estimated angle of attack θ2 ′ and the actual fin angle θ3 ′ is equal to or less than a predetermined value (for example, 2 °), and the predetermined oscillation cycle of the hull 2 (see FIG. 1) is set in advance. When the angle is equal to or greater than the threshold, fin angle control is performed based on the estimated angle of attack θ2 ′, while the difference between the estimated angle of attack θ2 ′ and the actual fin angle θ3 ′ exceeds a predetermined value. Alternatively, when the swinging period of the hull 2 is less than a predetermined threshold, fin angle control based on the actual fin angle θ3 ′ is performed.

  As described above, according to the fin stabilizer according to the present embodiment, when the oscillation period is not more than a predetermined period and the pressure in the upper and lower cylinder chambers of the hydraulic cylinder 12 cannot be accurately detected, the actual fin angle Since the vibration reduction control based on θ3 ′ is performed, it is possible to maintain the same level of accuracy as in the past. Further, when the difference between the actual fin angle θ3 ′ and the estimated attack angle θ2 ′ is equal to or less than a predetermined value, the vibration reduction control based on the actual fin angle θ3 ′ is performed, so that the control is stabilized. Is possible.

In addition, the fin stabilizer which concerns on 1st Embodiment mentioned above and 2nd Embodiment may have a computer system inside. A series of processing steps relating to the control of the fin stabilizer described above is stored in a computer-readable recording medium in the form of a program, and the above processing is performed by the computer reading and executing the program. Anyway.
Specifically, each arithmetic means in the fin stabilizer control system is such that a central processing unit such as a CPU reads the above program into a main storage device such as a ROM or RAM, and executes information processing / arithmetic processing. It is good also as what is realized by.
Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, in the first embodiment described above, the angle of attack is estimated based on the moment coefficient table shown in FIG. 4. However, the present invention is not limited to this example, and the angle of attack is derived by an arithmetic expression. May be. Further, as shown in FIG. 4, for example, when the moment coefficient is equal to or less than a predetermined value, the angle of attack and the moment coefficient are in a proportional relationship. Therefore, when the moment coefficient is less than or equal to a predetermined value, the angle of attack is easily calculated based on the arithmetic expression, that is, by multiplying the moment coefficient by the predetermined coefficient, and the moment coefficient is a predetermined value. When the angle exceeds, the corresponding angle of attack may be obtained based on the moment coefficient table as shown in FIG.

It is a control block diagram for demonstrating the effect | action which the fin stabilizer for ships which concerns on the 1st Embodiment of this invention exerts on a hull. It is the figure which showed the outline of the mechanical structure of the fin stabilizer which concerns on the 1st Embodiment of this invention. It is the block diagram which showed the control system of the fin stabilizer which concerns on the 1st Embodiment of this invention. It is the figure which showed an example of the moment coefficient table showing the correlation with moment coefficient Cm and angle-of-attack θ2. It is explanatory drawing for demonstrating the parameter used with the calculation formula of a moment coefficient. It is the block diagram which showed the control system of the fin stabilizer which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

23 Command generation unit 24 Angle of attack calculation unit 11 Fin 14 Flow rate adjustment mechanism 12 Hydraulic cylinder 16a Upper pressure sensor 16b Lower pressure sensor 25 Low-pass filter 27 Torque calculation unit

Claims (6)

A marine fin stabilizer comprising: a fin attached to a hull to reduce a fluctuation of the hull; and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull;
Pressure detecting means for detecting the pressure of the hydraulic cylinder;
Torque calculating means for calculating the torque of the fin based on the pressure;
Fin angle estimation means for estimating an angle of the fin with respect to the flow of seawater based on the torque;
Command generating means for generating a fin angle command for causing the estimated angle of the fin to coincide with a target angle for canceling the shaking of the hull, and
The fin driving device is a marine fin stabilizer that drives the fin based on the fin angle command. A fin angle detecting means for detecting an angle of the fin with respect to the hull;
The command generation means includes a fin for causing the fin angle detected by the fin angle detection means to coincide with the target angle when the hull oscillation period is equal to or less than a predetermined threshold value. The marine fin stabilizer according to claim 1, which generates an angle command. The pressure detecting means includes
Pressure sensors for detecting pressures in the upper cylinder chamber and the lower cylinder chamber of the hydraulic cylinder,
Noise removing means for removing a noise component included in the detection value detected by the pressure sensor;
The marine fin stabilizer according to claim 2, wherein the predetermined threshold is determined based on performance of the noise removing unit. Fin angle detection means for detecting the angle of the fin with respect to the hull;
A difference calculating means for obtaining a difference between the angle of the fin with respect to the seawater flow estimated by the fin angle estimating means and the angle of the fin with respect to the hull detected by the fin angle detecting means;
The command generation means, when the difference is greater than or equal to a predetermined value set in advance, a fin angle for causing the fin angle relative to the hull detected by the fin angle detection means to coincide with the target angle The ship fin stabilizer of Claim 1 which produces | generates instruction | command. A control method for a ship fin stabilizer, comprising: a fin attached to a hull to reduce fluctuation of the hull; and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull,
Calculating the torque of the fin based on the pressure of the hydraulic cylinder;
Estimating the angle of the fin relative to the flow of seawater based on the torque;
Generating a fin angle command for matching the estimated angle of the fin to a target angle for canceling the shaking of the hull;
A method for controlling a ship fin stabilizer, comprising: controlling the fin driving device based on the fin angle command. A control program for controlling a ship fin stabilizer comprising fins attached to a hull to reduce the fluctuation of the hull and a fin driving device having a hydraulic cylinder for adjusting an angle of the fin with respect to the hull. There,
Calculating the torque of the fin based on the pressure of the hydraulic cylinder;
Estimating the angle of the fin relative to the flow of seawater based on the torque;
Generating a fin angle command for causing the estimated angle of the fin to coincide with a target angle for canceling the shaking of the hull;
A control program for causing a computer to execute the step of controlling the fin driving device based on the fin angle command.

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