JPS6328794A - Autopilot device - Google Patents

Abstract

PURPOSE:To perform useful steering of a ship, by a method wherein a present position, a moving direction, and a speed are measured by means of a global position measuring system receiver, a distance in a vertical direction serving as displacement from a scheduled route is calculated, and a speed in a vertical direction is calculated to restore a displacement course to the scheduled route. CONSTITUTION:By means of a global position measuring system (NAVSTAR /GPS) receiver 2, an output is transmitted to a control device 1 which determines a present position T, the moving direction, and the speed of a ship under sailing. The control device 1 calculates a distance L0 in a vertical direction as displacement from a scheduled route 7 being a straight course running between a starting point S and an object point O. From the moving direction and a speed V, a displacement speed VH in a vertical direction as a displacement speed is calculated, and a speed VX in a vertical direction required for restoration to the scheduled route 7 is calculated. Through orderly repetition of the above computation, a time, in which a course is restored to the scheduled route, and a state can be grasped, by driving a steering device 5 through the working of a course control device 3, useful and efficient steering of a ship can be effected.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to an autopilot device that automatically steers a vehicle along a straight course between two predetermined points as a scheduled route.

tb+ Invention 1 Existing Summary The autopilot device according to the present invention automatically steers a straight course between two points as a scheduled route, and is characterized by a method of directing the course of a ship to the scheduled route in response to deviation from the scheduled route. has.

In particular, the present invention is designed to smoothly change the speed at which a vessel approaches a planned course in response to deviations from the planned course, thereby achieving efficient ship maneuvering.

fc) Prior Art A conventional so-called autopilot device has a magnetic compass equipped with a course setting device, and automatically steers the ship so that the ship always maintains a set heading. Such conventional autopilot devices have the disadvantage that the ship is swept along by the influence of tides and winds, and travels on a course that is parallel to the planned route. Therefore, an autopilot device has been developed using Loran C that has a navigation aid function that detects deviations from the ship's set course and automatically makes corrections while navigating.

In the case of an autopilot device using such Loran C, it is possible to determine the deviation from the current planned course as a distance, but it is not possible to immediately determine the direction and speed in which the ship is being carried by currents and winds. , it is not immediately clear how quickly the ship is approaching the planned route, resulting in wasteful maneuvering. As a result, fuel consumption increased and planned navigation was difficult.

(d) Problems to be Solved by the Invention This invention aims to improve efficiency by predicting the speed at which the planned route will be approached in accordance with the deviation from the scheduled route when automatically steering a straight course between two points as a scheduled route. The present invention provides an autopilot device that enables efficient automatic steering.

(Q) Means for Solving the Problems This invention provides an autopyro/route device that is equipped with a course control device that sets a course in a set direction and that automatically steers a ship using a straight course between two points as a planned course. A global positioning system (NAVSTAR/GPS) receiver that measures the current position, direction of movement, and speed of the ship, and deviation calculation that calculates the vertical distance of the ship's position determined by this receiver with respect to the planned route. means, deviation speed calculation means for calculating a speed perpendicular to the planned route from the moving direction and speed of the ship determined by the receiver, and calculating means for calculating the speed in the direction perpendicular to the planned route from the moving direction and speed of the ship determined by the receiver, and calculating the deviation amount at a specific time from the deviation amount, the deviation speed, and the ship speed. The present invention is characterized by further comprising a course setting means for determining a set course for the ship to approach the planned route at a speed of 0, and providing the set course to the course control device.

(f) Operation With the above configuration, the receiver of the global positioning system determines not only the current position of the ship but also the direction and speed in which the ship is moving every moment. From the position of the ship determined by this receiver, the deviation amount calculation means calculates the vertical distance to the planned route, that is, the distance between the straight line between two points and the ship's position, as the deviation amount, and the deviation speed calculation means The speed in the direction perpendicular to the planned route is determined from the direction and speed of the ship determined by the machine. The course setting means calculates a set course necessary for the ship to approach the planned route at a speed such that the deviation amount becomes O in a specific time from the deviation amount, deviation speed, and ship speed obtained in this way, and performs course control. feed into the device. As a result, the course control device performs steering to change the course to the set course and turns the ship.

The above series of processes are repeated at predetermined time intervals,
The course will be corrected each time.

For example, as shown in Figure 2, when the planned route is a straight course between the starting point S and the destination point ○, and the ship is at a position T that is deviated from this planned route, the distance L0 between the planned route and the ship is determined by the specified time. Adjust the ship's course so that it points to O. This specific time can be changed according to the ship's deviation from the planned course, but if it is a constant value, when the ship has sailed to position T', the distance of deviation L01 from the planned course is Again, the course is adjusted in the direction in which the ship approaches the planned route so that it becomes 0 at the specific time.

By controlling the ship's course from moment to moment in this way, the ship can be exponentially smoothly converged onto the planned course without overshooting the planned course.

FIG. 3 is a diagram illustrating a method for determining the course set by the course setting means.

Ship T is at a position deviated from the planned route by a distance L0, and is moving in the direction of arrow ■ at a speed of ■.

The ship itself takes a course from the starting point to the destination point by the action of the course control device, and the speed ■. However, due to the influence of currents and winds, the ship is drifting at speed ■8 as a component in the direction perpendicular to the planned route. In this way, the amount of deviation L0 and the deviation speed (8) are determined from the position of the ship, the direction of movement of the ship, and its speed.

Next, the ship is turned toward the planned route in order to go against the speed (8) caused by currents and winds and to reach the planned route in a specific time, changing the course. The speed at which this lead approaches the planned route■
8 can be obtained as (LO/k)-V, where k is the specific time. At this time, the speed of the ship in the direction of travel is ■. Therefore, as shown in the figure, by turning toward the planned route by an angle θ8, an approach speed of 8 to the planned route can be obtained.

(g) Embodiment FIG. 1 is a block diagram of an autopilot device according to the present invention.

The control device 1 processes data from various measuring devices and setting devices, and provides a set course to the course control device 3. GP
S receiver 2 is a global positioning system (NAVSTAR/G
PS) is a receiver, which determines the current position (latitude, longitude) of the ship and the moving speed of the ship in two-dimensional directions, and outputs it to the control device 1. The ship speedometer 6 is a device that measures the speed of the ship in the course direction, and outputs the data to the control device 1. The scheduled route setting device 7 sets the positions of the departure point and destination point as latitude and longitude data.

The course control device 3 includes a compass, and changes course by driving the steering device 5 so that the ship follows the set course given by the control device 1. Further, the direction of the rudder outputted from the follow-up transmitter 4 is detected to control the rudder angle.

FIG. 4 is a flowchart showing the processing procedure of the control device. First, the current position of the ship is determined from the GPS receiver in latitude P.
N, longitude P□, and the moving speed of the ship as latitude speed ■8 and longitude speed ■ (nl-=n
2). Next, measure the deviation from the ship's position determined by nl to the ship's planned route.

is calculated (n3). This calculation is performed as follows.

FIG. 5 is a diagram for explaining the method.

In the figure, the starting point position is represented by (LATs, LONs), the destination point position is represented by (LATo, LONo), and the ship position is represented by (LATt, LONt). P is the point where the perpendicular to the ship's planned route intersects, and Lo is the amount of deviation. Further, ΔLON and ΔLAT each represent the distance between the current position of the ship and the starting point. In such a relationship, the following relational expression holds true.

ΔLAT=K(LATt-LATs) ΔS0N=K(LONt-LONs) cos LA
Ts Here, K is a conversion coefficient of distance to latitude, so the amount of deviation L0 can be found as follows.

LO=ICO3(2*ΔLAT-sin tx *ΔL
ON + where α is cx = jan-' (LATo-LATs)/(
It can be obtained from LONo-LONs)*cosLATs.

The above is a case where the earth can be treated as a flat surface.

If ΔLAT is sufficiently large, Lo is determined according to the spherical triangle formula.

After determining the amount of deviation L0 in this manner, the deviation speed 8 is calculated as shown in FIG. 4 (n4).

As shown in Figure 3, the speed ■ is calculated from the ship's latitude speed ■8 and the longitude speed ■, and this is calculated as the speed ■ in the direction parallel to the planned route. It can be obtained by dividing into 8 and the velocity in the direction perpendicular to the planned route. Next, the speed ■8 at which the vehicle should approach the planned route is calculated (n5).

This speed VX is obtained from (LO/k)-VM, where k is the specific time as described above. However, here, the deviation velocity V is positive in the direction of approaching the planned route and negative in the direction of moving away from the planned route.

Furthermore, the turning angle θ8 of the ship is calculated from this approach speed ■8 (n6). As is clear from the relationship shown in FIG. 3, this angle θ8 is obtained by calculating θ8·90°−cos−′ (Vx/Vc). By providing the turning angle θ8 thus obtained to the course control device, a new course is set and automatic steering is performed.

The above processing is performed at predetermined time intervals (n?, -nl)
.

In addition, in the example, the speed at which the ship approaches the scheduled route is determined from the condition that the amount of deviation becomes 0 at a specific time, and the specific time is set as a constant, but this value is used as the value of the amount of deviation L0. It is also possible to change the value according to the purpose of navigation.

(h) Effects of the Invention As described above, according to this invention, a course is set by turning the ship based on the amount and speed of deviation of the ship from the planned route, but the purpose of this turning is not to determine the heading. This is done to correct the speed at which the ship approaches the planned course, and because it gives the ship time to time to approach the planned course, efficient ship maneuvering can be carried out. Wasteful steering such as turning back to the planned route again is not performed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an autopilot device according to an embodiment of the present invention, FIG. 2 is a diagram showing the progress of a ship approaching a scheduled route by the autopilot device of this invention, and FIG. 3 is a diagram showing how the ship approaches its scheduled route. A diagram illustrating the amount of deviation, the speed of deviation, and the angle at which the ship should turn based on these values. Fig. 4 is a flowchart showing the processing procedure of the autopilot device according to the embodiment of this invention. Fig. 5 is the starting point and purpose. FIG. 3 is a diagram illustrating a method of calculating a deviation amount from the position of a point and the position of a ship. 1-control device, 2-GPS receiver, 3-course control device.

Claims (1)

[Claims] (1) An autopilot device that is equipped with a course control device that sets the course in a set direction and automatically steers a straight course between two points as the planned route, measures the current position, direction of movement, and speed of the ship worldwide. Positioning system (NA)
a VSTAR/GPS) receiver; a deviation calculation means for calculating the vertical distance of the ship's position determined by the receiver with respect to the planned route; a deviation speed calculating means for calculating the speed in the vertical direction, and calculating a set course for the ship to approach the scheduled route at a speed such that the deviation amount becomes 0 at a specific time from the deviation amount, the deviation speed, and the ship speed. An autopilot device comprising: , a course setting means for providing the course to the course control device.