JP2629179B2 - Ship course change control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a course change for smoothly changing a course of a ship along a set course when the ship navigates along a course having a course change point by automatic control. The present invention relates to a control device.

[Prior Art] In general, when changing the course of a ship, after turning the rudder in the direction in which the course is to be changed and maintaining a constant rudder angle, the rudder is reversed when the heading changes to some extent, the turning motion is stopped, and the rudder is returned to the center. .
FIG. 3 shows this steering state, where t indicates time, δ indicates a steering angle, and ψ indicates an azimuth (turning angle).

When this course change operation is performed on the ocean, it is not necessary to particularly consider the route after the course change, but in a narrow sea area such as a bay, it is necessary to perform the course change operation along a given route (set route). However, the ship does not respond immediately even if the rudder is operated, because the inertia of the ship is much greater than the turning force of the rudder. Therefore, the course cannot be smoothly and correctly changed from the current route to the new set route unless the course of the course is started by predicting the motion of the ship in advance.

Conventionally, the course change operation is manually performed by a boat operator, and when the course approaches the course change point, the target direction is gradually changed, and the course is changed by following the target direction. The degree of approach to the turning point when the turning is started and the change in the target direction are determined by trial and error depending on the intuition of the operator. The same applies to the case of shifting from straight-line maneuvering to straight-line navigation, again relying on the intuition of the operator.

[Problems to be Solved by the Invention] However, in the above-described conventional method, a skilled boat operator is necessary because the needle changing operation is dependent on human intuition, and a new boat type requires a long time until the boat operator becomes proficient. However, there were cases where the course changed too much or the course changed quickly, and the course could not be changed to the correct setting route, which was accompanied by danger. In particular, when the steepness angle is large, it is difficult to predict the movement of the ship by human intuition, and there is a problem that the deviation from the channel increases.

[Means for Solving the Problems] The present invention is based on the set route and the position of the own ship, the speed of the own ship, and based on the basic formula of the changing course, the changing time of the changing course, the turning angle during the changing course, the turning angular velocity. A computing unit that predicts and computes; a detector that detects the actual turning angle and turning angular velocity during the changing movement of the needle; and a change of the needle based on the predicted calculation result from the computing unit and the actual detection result from the detector. And a steering controller for controlling the steering angle at the same time and controlling the steering angle so that the predicted turning angle, the turning angular speed and the actual turning angle and the turning angular speed coincide with each other during the course of the turning movement. It is a feature.

[Operation] When the calculated turning timing is reached, the steering controller drives the rudder by a predetermined steering angle based on a signal input by the calculator. Further, during the course of the turning, the steering angle at which the actual turning angle and the turning angular speed fed back from the detector coincide with the turning angle and the turning angular speed calculated by the calculator are adjusted.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

First, according to the present invention, when a ship navigates along a route having a turning point P by automatic control, the changing movement of the ship is predicted and calculated in advance, and the value of the steering angle to be taken and the position of the turning point before the turning point P are calculated. Information such as whether to start, and feedback the detection result while detecting the position and attitude of the ship during course change,
The purpose is to make the ship automatically change course.

 T + = Kδ (1) is given as a basic motion equation of the needle movement, and information necessary for the needle movement is obtained from the equation.

Here, ψ: turning angle,: turning angular velocity,: turning angular acceleration, δ: steering angle. K indicates the ratio of the resistance of the water to the turning force of the rudder, that is, the strength of the turning force inherent in the ship, and T indicates the ratio of the resistance of the water to the inertia of the ship, that is, the ratio of the resistance to the steering. This indicates the quickness of exerting the turning force.

In order to change the hands, steering is performed as shown in FIG. That is, the steering angle is set to the steering angle δ _{0 in the} direction in which it is desired to turn, the rudder is reversed at time t ₁ when the turning angle changes to the target turning angle to some extent, the turning motion is stopped, and the steering is returned to the center. If the turning angular velocity (differential value of the turning angle) is zero when the rudder is returned to the center, the turning is completed.

The turning angle (azimuth) of the ship before changing the course is set to zero, and φ
Considering the case where the hand is changed by _{0, the} time required for steering (the time required for changing the steering angle) is ignored to facilitate handling.

The conditions for obtaining the steering pattern shown in FIG. Becomes By solving the equation (1) under the condition (2), the following equation is obtained.

When returning the steering to the center, i.e. in order to complete the veering in t ₂ at _{t 2 <t (t) =} 0, it may be a phi _0. Therefore, from equations (5) and (8), In order for Equations (9) and (10) to hold the same, the following conditions only need to be satisfied.

From equation (12) Substituting this into equation (11) here The above equation is a quadratic equation for x.

ax ² −2x + 1 = 0 (13) By solving the equation (13) for x, and further obtaining t ₁ and t ₂ ,
The following equation is obtained.

The value obtained by substituting t ₁ in equation (14) into equations (6) and (7) is as follows.

The inversion time of the rudder, using the t ₁ no (16),
It is assumed that the rudder is reversed when the azimuth changes to ψ (t ₁ ).

The steering method for changing the course has been described above. Next, what kind of track the ship follows during that time will be considered.

In general, when a ship turns, it has a certain lateral flow angle β as shown in FIG.

Here, Vs: speed of the ship L: length of the ship Equation (17) is a relationship during steady turning, but it is assumed that this holds true during the course of the course of the course, and the change in boat speed during the course of the course of the course is small. Is assumed to be constant, the following expression is obtained as an approximate expression of the cross flow angle β (t) during the needle movement.

As shown in FIG. 6, the distance lx of the ship traveling in the direction of the course before the course of the course changes and the distance ly traveling of the direction perpendicular to the course during the course of the course change integrate the velocity components in the respective directions of the ship speed Vs. Obtained by:

Here, Vs (t) uses a constant value or an equation that gives a change in the boat speed during the course of the needle movement estimated from the results of the turning test and the like.

The course change point P is given at the intersection of the course before the course change and the course after the course change, and the distance l from the start of steering to the course change point P is given by the following equation.

Note that ψ (t), (18), (19), and (20)
(T) is given by the formula in (3) (4), (6) (7).

Therefore, if the maneuvering at a turning point is started at a point 1 before the turning point, the turning can be performed according to the route.

The above-mentioned method is a basic maneuver for changing the course, and cannot cope with the estimation error and disturbance by the equation (1). Therefore, such a problem is addressed by the method described below.

Ships that are actually navigating may not always be completely navigating on the intended route. Therefore, as shown in FIG. 6, assuming a new route Z and border X such as are distance l sinψ ₀ between the parallel parallel lines between the veering point P and the ship, the boundary At the point where the line X is reached, it is assumed that the needle starts to move.

In addition, feedback control is performed to make the movement during the needle changing movement closer to the predicted movement. That is, the steering angle is not fixedly held at δ ₀ during the course of the changing course, but the turning angle during the changing course,
Feedback (3), (4), (6)
The steering angle is adjusted so as to approach equation (7).

δ ^* = δ ₀ −Kp (ψ _a −ψ (t)) − K _D (a−
(T)) (22) where δ ^* : rudder angle during the turning movement ψ _a , _a : turning angle, turning angular velocity during movement, K _P , K _D : feedback gain.

The basic method of maneuvering according to the present invention has been described above. An automatic control device for performing maneuvering based on the basic method will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes an own ship position measuring instrument, which includes a radar, a laser measuring instrument provided on the own ship, or a triangular survey using radio waves, sound waves, lasers, or the like by equipment provided on the ground. A measuring device or the like that measures the position of the ship and communicates the result to the ship is cited, and the measurement result is input to the calculator 4. The navigation speed of the ship is detected by the speed detector 2 and input to the arithmetic unit 4. Reference numeral 3 denotes a route setting device, which is used by a ship operator to set the position of a special point on the route based on a chart or the like, and this setting is also performed by a command from a land-based control tower. This setting result is input to the arithmetic unit 4. The arithmetic unit 4 calculates data necessary for steering from the setting input signal and the position of the ship. The calculation result and the detection results of the turning angle detector 5 and the turning angular velocity detector 6 are input to a steering controller 7, and the steering controller 7 converts the signals input from the arithmetic unit 4 and the detectors 5 and 6 into signals. Then, the steering device 8 is driven to adjust the steering angle of the rudder.

 The operation of the present invention will be described below with reference to FIG.

The turning point P, turning angle ψ ₀ , initial steering angle δ from the route setting device 3
₀ is input to the arithmetic unit 4. The computing unit 4 performs the calculations of the above equations (2) to (21) based on the equation (1), and calculates the changing point start position, the changing point before the changing point P, Ask for. When it is confirmed from the position detection result from the position measuring device 1 that the own ship has reached the turning start position, the steering controller 7 determines that the steering angle should be δ ₀ and sets the steering angle to δ ₀ . The steering device 8 is driven as required.

Further, the steering controller 7 is supplied with the turning angular velocity _a during the actual movement from the turning angle detector 5 and the turning angular velocity detector 6, and the arithmetic unit 4 outputs the expected turning angle ψ at each time.
(T), the turning angular velocity (t) (arithmetic unit) are input, and the corrected steering angle δ ^* is obtained from both inputs by the following equation (11).

δ ^* = δ ₀ −K _P (ψa−ψ (t)) − K _D ( _a−
(T)) (11) if a detection result and the calculated value match from both detectors _{5,6, φ a -φ (t)} = 0 a - (t) = 0 and turned by [delta] ^* = Of course, it is δ ₀ .

Next, ψ (t) calculated in the calculator 4 is as follows: At this time, a signal of the steering angle −δ ₀ is input to the steering controller 7. The steering controller 7 inverts until a - [delta ₀ steering based on the signal.

After the inversion, ψ (t) (Equation (5)) from the arithmetic unit 4;
Based on (t) (Equation (6)) and the detection results from the turning angle detector 5 and the turning angular velocity detector 6, the steering controller 7 calculates the corrected steering angle δ ^* in the same manner as described above, and controls the steering device 8 Control.

Veering maneuvering when turning angle [psi of (t) reaches the [psi ₀ is completed.

When the needle changing operation is completed, the operation shifts to automatic navigation for a new route (straight route) set and input by the route setting device 3. [Psi ₀ input by route setter 3 is zero, therefore, a reference is also zero steering angle, which is controlled by the steering controller 7.

Note that the turning angle ψ (t) is It may be determined that the needle changing maneuver is completed at the time when it becomes larger, and thereafter, the navigation may be shifted to the automatic navigation for the new straight route.

[Effects of the Invention] As described above, according to the present invention, a ship operator only needs to set and input a navigation route, and actual maneuvering of a needle does not require the operation of the ship operator, so that no human error occurs. The needle changing operation can be performed accurately and safely, and no skill is required. Therefore, even when the hull is changed, the appropriate needle changing operation can be immediately performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a flowchart showing the operation in the embodiment, FIG. 3 is a diagram showing a maneuvering pattern of a needle changing maneuver, and FIG. FIG. 5 is a diagram showing the influence of a lateral flow when turning, and FIG. 6 is a diagram showing a method of maneuvering when a navigating ship is off a planned route. . 1 is a position measuring device, 2 is a speed detector, 3 is a navigation device, 4
Is a calculator, 5 is a turning angle detector, 6 is a turning angular velocity detector,
Reference numeral 7 denotes a steering controller, and 8 denotes a steering device.

Claims (1)

(57) [Claims] An arithmetic unit for predicting and calculating a turning time, a turning angle during turning, and a turning angular velocity based on a set route and a position of the ship, and a speed of the ship, based on a basic formula of the changing movement; A detector for detecting the actual turning angle and the turning angular velocity during the course of the needle movement, and based on the calculation result predicted from the calculator and the actual detection result from the detector, the steering angle is controlled at the course of the turning, and A steering control device for a ship, comprising: a steering controller that controls a steering angle so that a predicted turning angle, a turning angular speed, and an actual turning angle and a turning angular speed coincide with each other during a turning motion.