JPH0338158B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an automatic steering device used to determine the course direction of a ship, and the invention is an automatic steering device that is used to determine the course direction of a ship. -Related to improvements to automatic steering devices for ships that transmit steering amounts by performing differential calculations.

<Prior Art> FIG. 1 is a block diagram of an automatic steering system for a ship 1.

In the figure, reference numeral 2 denotes a course direction setting device for setting the course direction of the ship 1, which outputs a set course direction signal i and a course change command signal k. 3 is a course direction detector which outputs a course detection signal j. 4 is each signal (i,
This is an arithmetic control device that performs proportional, integral, and differential calculations based on the steering amount δ (j, k) and transmits the steering amount δ. A comparator 5 compares the output of the steering angle detector 6 which detects the steering angle of the steering gear 8 with the steering amount δ. 7 is a drive device that drives the steering gear 8.

FIG. 2 is a block diagram of a conventional arithmetic and control unit 4 used in the automatic steering system shown in FIG.

In FIG. 2, numeral 41 is a course calculation circuit which inputs a set course direction signal i and a course detection signal j, calculates and outputs a deviation signal l. 42 is a proportional calculation circuit that outputs a deviation amount δp proportional to the magnitude of the deviation signal l. Reference numeral 43 denotes a differential calculation circuit that performs differential calculation on the deviation signal l and outputs a steering amount δD for improving course-keeping performance, which operates on the turning angular velocity of the bow of the ship 1.
Reference numeral 44 denotes an integral calculation circuit that performs an integral calculation on the deviation signal l and outputs an integral quantity δI for correcting deviations between the course and heading due to wind and waves, currents, etc. When the course change command signal k is received, this integral calculation circuit 44 performs an integral calculation on the deviation signal l. The circuit configuration is such that the quantity δI is reset to zero. That is,
The steering amount δ of the arithmetic and control unit 4 is normally δp + δI + δD, and when the course change command signal k is received, it is δp + δD.
Thus, the ship 1 is placed on the newly set course direction, and course overshoot due to course change is minimized to improve course keeping.

FIG. 3 is a diagram showing the operational status of the ship 1 shown in FIG. 1.

In Figure 3, Xa and Xb are the newly set course direction,
Let A be the time before the course change, B be the time the course start, and C and D be the end time of the course change. F is an external force acting on the ship 1 due to wind and waves, tidal currents, etc., and is assumed to have an angle of θ with respect to the ship 1 in the figure. α is the steering angle at time A before changing course, φ and -φ are time B at the start of changing course.
Let β be the steering angle at time point B when the course change starts. On the other hand, the external force F acts on the ship 1 at Fsin θ at the time point B when the course change starts, Fsin (θ+φ) at the time point C when the course change ends, and Fsin (θ−φ) at the time point D when the course change ends.

By the way, in the automatic steering system, as mentioned above, with a steering method in which the integral amount δI is simply reset to zero at the start of a course change, there is a problem in that the influence of external force F due to wind and waves, currents, etc. cannot be ignored. That is, when the integral amount δI is reset to zero, the ship 1 takes a course direction that is largely drifted to the right from the newly set course directions Xa, Xb, as shown by the dashed-dotted lines Ya, Yb in FIG. In general, the integral time constant is usually much larger than the differential time constant.
Since the integral calculation circuit 44 starts working from the time points C and D when the course change ends, the desired course direction cannot be approached until a very long time and distance have elapsed.

<Purpose of the Invention> The present invention has been made to solve the above-mentioned problems of the prior art, and is capable of minimizing course errors when changing course and allowing a ship to quickly navigate to a newly set course direction. It is an object of the present invention to provide an automatic steering device that achieves the following.

<Configuration of the Invention> In order to achieve the above-mentioned object, the configuration of the automatic steering system of the present invention is to detect the deviation between the set course direction given from the ship's course direction setting device and the actual course direction obtained from the course direction detector. The proportional calculation circuit of the arithmetic and control unit performs a proportional calculation on the amount, the integral calculation circuit that can reset the integral amount to zero when a course change command signal is received performs an integral calculation, and the differential calculation circuit performs a differential calculation to obtain a predetermined steering amount. In the automatic steering device that transmits the signal, a primary storage circuit is provided to which the output of the integral calculation circuit is guided and the integral amount of the integral calculation circuit during course change is set as a predetermined fixed integral amount, and the input of the integral calculation circuit is set as the deviation amount. As an input and an output of the primary storage circuit, if both the steering angle and the fixed integral amount are larger than their respective reference values at the time of starting the course change, the integral control output during the course change from the course change start point to the course change end point after the course change command is issued. is held at a predetermined value at the time of course change, and if the fixed integral amount is smaller than the course change angle at the time of course change start, the integral control output during course change after the course change command is reset, and the course change angle is set at the course change start point. If the fixed integral amount is large compared to the above-mentioned course change command, the integral control output during the course change will maintain the value at the time of course change, and if both the course change angle and the fixed integral amount are small at the time of starting the course change, the value will be maintained even during the course change. The integral control is continued as is, and the integral amount after the end of the course change is determined by restarting the same calculation as before the start of the course change from the state at the end of the course change.

<Embodiment of the Invention> FIG. 4 is a block diagram of an embodiment of the arithmetic and control device according to the present invention. used. In Figure 4, parts and functions that are the same as those in Figures 1 to 3 are designated by the same numbers and functions.
It will be expressed using symbols and its explanation will be omitted.

The flowchart of FIG. 4 is shown in FIG.

In FIGS. 4 and 5, 46 is an integral calculation circuit. Let δIb be the integral amount of the integral calculation circuit 46 between the course change start point B and the course change end point C shown in FIG. (hereinafter referred to as "fixed integral amount"). The integrated calculation circuit 46 compared the variable across φ at the start of the variable needle and the fixed integrated integration ΔI ′ at that time, compared to the standard variable angle φ ₀ and the reference integral ΔI ₀ , each of which is the standard value, and the underwhearm integrated ΔIB. 4 shown below
Output the actual value. In addition, the reference change angle φ ₀ ,
The value of the reference integral amount δI ₀ may be built into the integral calculation circuit 46 or may be inputted from the outside. Reference numeral 47 denotes a primary memory circuit, which is provided to set the integral amount δIb during course change to a fixed output (for example, (2/3)·δi′), which will be described later. It's okay.

Here, the reference turning angle φ ₀ is 6° in absolute value (|6|
), and the reference integral quantity δI ₀ is 4° (｜4｜
゜). Although this value is determined based on past operational records and ship motion simulation, it is not limited to this value and may be changed as appropriate. If we now find the relationship between the standard course angle φ ₀ , the standard integral amount δI ₀ , the course change angle φ, and the fixed integral amount δI′, we get <> φ≧φ ₀ = |6|゜, δI′≧δI ₀ = |4|゜＜＞ φ≧φ ₀ =｜6｜゜, δI′＜δI ₀ =｜4｜゜＜＞ φ＜φ ₀ =｜6｜, δI′≧δI ₀ =｜4｜゜＜＞ φ＜φ ₀ = |6|°, δI′<δI ₀ = |4|°.

Figure 6A shows the operational status of the ship 1 in these four ways, and Figure 6B shows the integral quantities at that time. Below, FIG. 6 will be explained.

<> is the course change angle φ at the time point B when the course change starts
Both the fixed integral quantity δI′ and the reference steering angle φ ₀ = |6|
This is the case when the reference integral amount δI ₀ =|4|° is larger. Therefore, in this case, the integral amount ΔIb during course change is fixed at a predetermined state as shown in (B), that is, (2/3)·ΔI′. That is, the steering amount δ is δp+
(2/3)・δI′+δD. The integral amount δI after the course change end points C and D restarts the same calculation as before the start of the course change from the state of (2/3)・δI′ as shown in (b), so the steering amount δ becomes δp + δI + δD (hereinafter , the steering amount δ after the restart is expressed in the same way, so it will be omitted).

<> is the course change angle φ at the time point B when the course change starts.
This is the case when the fixed integral amount ΔI' is small compared to , that is, when the offset of the course due to the effects of wind and waves, currents, etc. is small. Therefore, if there is an integral amount δI', it becomes difficult to follow the target course, so the fixed integral amount δI' is reset to zero as shown in (B) (integral amount during course change δIb=
0), and the steering amount δ is set to δp + δD. For the integral amount δI after the course change end points C and D, the same calculation as before the start of the course change is restarted from a zero state.

<> is the course change angle φ at the time point B when the course change starts.
This is the case when the fixed integral amount δI' is larger than . Therefore, if the integral amount ΔIb during course change is held at a fixed integral amount ΔI′ as shown in (b), the course change performance will be better, so the steering amount δ will be Δp+δI′+δD. C, D at the end of course change
The subsequent integral amount ΔI restarts the same calculation as before starting the course change from the state of the fixed integral amount ΔI'.

<> is the course change angle φ at the time point B when the course change starts.
This is a case where both the fixed integral amount ΔI′ and the fixed integral amount ΔI′ are small. Therefore, since the integral amount δIb during course change is better if the operation is continued with the integral amount δI, the steering amount δ becomes δp + δI + δD over the entire section.

As described above, by changing the fixed integral amount ΔI' according to each condition, it is possible to minimize the heading error when changing course.

Note that, in addition to the reference deflection angle φ ₀ and the reference integral amount ΔI ₀ , for example, an azimuth may be added as the reference value. That is, in this case, if the heading and the rudder angle β are in the same direction, the steering amount δ is δp + δI′ + δD, and if they are in different directions, the steering amount δ is δp + (2/3)・
By setting δI′+δD, it is possible to take a better course after starting the course change.

Further, the above-mentioned arithmetic and control device 4 may be constituted by a microcomputer.

<Effects of the present invention> As described above, according to the present invention, which compares the course change angle, fixed integral amount, course change direction, etc. at the time of starting the course change with each reference value, and outputs the best integral amount, wind and wave Since the operation of the ship is not affected by tidal currents, etc., errors in changing course after changing course can be kept to a minimum, and energy savings can therefore be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an automatic steering system for a ship, FIG. 2 is a block diagram of a conventional calculation device, FIG. FIG. 5 is a flowchart of FIG. 4, and FIG. 6 is a diagram of the operation status of the ship according to the present invention. 1... Vessel, 4... Arithmetic control unit, δ... Steering amount, φ... Course change angle, α, β... Rudder angle.

Claims (1)

[Claims] 1 The proportional calculation circuit of the arithmetic and control unit performs a proportional calculation on the deviation between the set course direction given by the ship's course direction setting device and the actual course direction obtained from the course direction detector, and a course change command signal is generated. In an automatic steering system that transmits a predetermined steering amount by performing integral calculations with an integral calculation circuit and performing differential calculations with a differential calculation circuit, the output of the integral calculation circuit is guided to perform integral calculations during course changes. A primary storage circuit that sets the integral amount of the circuit to a predetermined fixed integral amount is provided, and the input of the integral calculation circuit is used as the deviation amount input and the output of the primary storage circuit, so that both the course angle and the fixed integral amount are set at the time of starting the course change. If it is larger than each reference value, the integral control output during the course change from the time when the course change starts to the time when the course change ends after the course change command is held at a predetermined value at the time of course change, and the If the fixed integral amount is small, the integral control output during the course change after the course change command is reset, and if the fixed integral amount is larger than the course change angle at the time of starting the course change, the integral control output during the course change after the course change command is reset. If the value at the time of course change is held, and both the course angle and the fixed integral amount are small at the time of course change start, the previous integral control will continue as is during course change, and the integral amount after course change ends will change from the state at course change end. An automatic steering device characterized by restarting the same calculation as before starting.