JPH0417837B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an automatic steering method that performs steering by obtaining control information from a ship navigation device such as Loran C. [Prior art] As control information in a ship's automatic steering system,
When using the angular difference between the destination position and the own ship's course, or heading, the data from a sensor (e.g. Loran C receiver) will cause overcontrol due to wandering and delayed reaction, and the ship will be unable to steer. This is accompanied by the phenomenon of deviating from the course. Therefore, in order to prevent steering due to data fluctuation, a method is generally adopted in which no control is performed when the angle difference is less than a certain value. [Problems to be Solved by the Invention] In the method described above, the absolute amount of course deviation is not managed, so the route tends to become arched due to the influence of tidal currents and the like. Another method is to obtain only information on course deviations from sensors, and then steer the ship in the direction of returning to the course if it deviates from the course, but in this case, the rudder angle is not in the direction of the destination, but rather Since it points upwards, it has the disadvantage that severe meandering across the course is likely to occur. In order to avoid this, a method is disclosed in Japanese Patent Application Laid-Open No. 79408/1983 that is necessary to overcome the disturbance and keep the amount of course deviation constant. The helmsman must adjust and select calculation constants etc.
If this adjustment selection is inappropriate, there will be inconveniences such as the inability to reach the destination if large course deviations remain in the vicinity of the destination, or complex and incomplete points will remain. Therefore, there is a problem in that it is desired to provide products by a method that does not cause such inconvenience. [Means for Solving the Problems] The present invention is capable of solving the above problems by using a control method that makes conditional judgments using the angular difference between the destination position and the navigation direction and the amount of course deviation as control information. This is what I did. [Example] Hereinafter, an example using the method of the present invention will be described with reference to the drawings. In the figure, 1 is the starting point of the ship, 2 is the destination point, and 3 is the route or course connecting these points. 4 indicates the position of the ship at a certain point in time, and 5
is the destination position at this time, and 6 is the navigation direction. These 5 and 6 are indicated by angles α and β with respect to the azimuth looking toward due north N from the ship's position. As can be seen from the figure, ΔD is the angular difference between α and β. Also ±Δd
is the fluctuation width of ΔD. The above α and β are obtained from the navigation device 10 such as the Loran C receiver shown in FIG. From the data, the average value (±ΔD) of the difference between β and α is calculated using a calculation circuit 11.
In addition, the fluctuation width (±Δd) is calculated using 12 calculation circuits.
To calculate the fluctuation width, use the range or variance obtained from the maximum and minimum values. ΔD and Δd obtained in this way are 13
When ΔD>Δd in the output condition judgment circuit, ΔD
When ΔD≦Δd, 0 is output and applied to the 16 output circuits. On the other hand, in FIG. 1, Δl is the amount of deviation of the ship 4 from the course 3, and this is also obtained from the navigation device 10 such as Loran C. This Δl is a constant L set by the user to limit the amount of steering angle correction due to course deviation.
(tolerable range of course deviation), with a detection circuit of 14 and an output condition judgment circuit of 15, L≦
When Δl, Δd obtained in step 12 is output as the steering angle in the direction of returning to the course, and when L>Δl, 0 is output and applied to 16. The output circuit 16 uses the outputs 13 and 15 to output the corrected steering angle as shown in Table 1, and outputs the corrected steering angle to the steering device 17.
is applied to correct the course.

[Table] Next, FIG. 3 is a block diagram of another embodiment of the present invention. In this embodiment, the fluctuation width (±Δd) of the difference between the destination position 5 and the navigation direction 6 of the own ship 4 is
Instead, a constant value θ determined empirically is used. This eliminates the need for the Δd calculation circuit 12 shown in FIG. 2, which has the advantage of simplifying the overall configuration.
In addition, 18 in FIG. 3 is a setting circuit for the above-mentioned constant value θ, and this output is also applied to 13 and 15, so in 13, ΔD and θ are compared, and in 15, L≦ When Δl, θ becomes the output of the return steering angle. Therefore, the output from 16 is as shown in Table 2.

[Table] [Effects of the Invention] As described above, the present invention uses both the angular difference between the destination position and the navigation direction and the amount of course deviation as control information for the automatic steering system, and (a) calculates the amount of course deviation; Limits are placed on steering angle corrections. (b) A threshold value is set for the control switching angle between the angular difference information between the destination position and the navigation direction and the course deviation information. (c) This threshold value uses the fluctuation width of the angle difference information. As a result, the course is not deviated from, and large meandering and small frequent control operations can be suppressed, enabling smooth automatic steering, and also allowing the helmsman to avoid deviations depending on the magnitude of the disturbance. There is no need to make adjustments or selections, and control is performed using angle information for the purpose, so it is possible to accurately automatically steer to the destination even if it is close to the destination. It has the advantage of providing an extremely effective control method in terms of safety and fuel efficiency.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the present invention, FIG. 2 is a block diagram of an embodiment of the invention, and FIG. 3 is a block diagram of another embodiment of the invention. 1... Departure point, 2... Destination point, 3... Course, 4... Ship position, 5... Destination position, 6...
Navigation direction, 10... Navigation device, 11, 12... Calculation circuit, 13, 15... Output condition judgment circuit, 14
...Detection circuit, 16...Output circuit, 17...Steering device, 18...Constant value setting circuit.

Claims (1)

[Claims] 1. An automatic steering method that performs steering by obtaining control information from a ship navigation device such as Loran C, which a. a first step of calculating the average value (±ΔD) of the difference between the destination position and the navigation direction and the fluctuation width (±Δd) of this average value; b. Δd, and only when ±ΔD>±Δd holds, the second process outputs ΔD as a corrected rudder angle; c) the input deviation amount of own ship position from the course (Δl); a third step of comparing a constant (L) set by a user or the like, and outputting the Δd obtained in the first step as the return angle to the course only when Δl≧L holds; d From the outputs of ΔD and Δd obtained from the second and third processes, when there is the ΔD output as the steering angle output, the ΔD is
and a fourth step of setting the Δd output as the steering angle output when there is no ΔD output and the Δd output, and 0 output when both the ΔD and the Δd output are absent; A method for controlling an automatic steering system, comprising: a fifth process in which the output obtained in the fourth process is applied to a steering system. 2. The control method according to claim 1, wherein the fluctuation width (±Δd) of the difference between the destination position and the navigational direction of the own ship is determined by an empirically determined constant value (θ).
A control method characterized by: