JP2003232636A - Azimuth detecting method, azimuth detecting device, navigation device, portable instrument, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an azimuth detecting method in which a calculating expression for finding a declination is made unnecessary, an azimuth detecting device, a navigation device incorporating the azimuth detecting device, a portable instrument, and a program. <P>SOLUTION: This azimuth detecting device is equipped with a CPU 12, a geomagnetism sensor 18, and an azimuth display device 22. The CPU 12, when a target point and the present position are set, displays a line connecting the present position and the target point or its direction on the azimuth display device 22, finds a true azimuth based on the present position and a position coordinate of the target point, and takes in the output from the geomagnetism sensor 18 in a state that the course or the direction displayed on the azimuth display device 22 agrees with the direction of an actual target point, and finds the declination based on the true azimuth and the output of the geomagnetism sensor 18. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azimuth detecting method, an azimuth detecting device, a navigation device, a portable device, and a program, and more particularly to detecting a declination.

[0002]

2. Description of the Related Art Conventionally, a car navigation system or the like has a built-in azimuth detecting device, and navigation is performed based on the azimuth output detected by the azimuth detecting device. A geomagnetic sensor is used for this azimuth detecting device. The geomagnetic sensor detects the azimuth of the magnetic pole. Since the magnetic north (magnetic azimuth) and true north (true azimuth) have different azimuths, a declination occurs. That is,
Magnetic north at any point produces a declination that is the deflection angle from true north. Then, this declination differs at any point on the earth, and the declination is large at a point close to the magnetic pole, and the compass is unreliable.

[0003]

In order to solve the above problems, for example, Japanese Unexamined Patent Publication No. 8-278139 proposes a method for determining the true azimuth based on the output of the geomagnetic sensor and the deflection angle. The declination is calculated directly from the latitude and longitude.

However, since the magnetic pole changes year by year, the calculation formula must be changed accordingly and maintenance is required. Also, in the place where the geomagnetism is locally deviated, the output of the geomagnetic sensor is also inaccurate, so
As a result, the calculation of true north based on the output was also inaccurate.

The present invention has been made in order to solve the above problems, and incorporates an azimuth detecting method, an azimuth detecting device, and the azimuth detecting device which do not require a calculation formula for obtaining a deviation angle. It is intended to provide a navigation device, a mobile device, and a program.

[0006]

(1) An azimuth detecting method according to one aspect of the present invention is based on a step of setting a target point and a current position, respectively, and based on the current position and the position coordinates of the target point. A step of obtaining a true azimuth, a step of displaying a line connecting the current position and the target point or its direction on a display means, and a direction of the line displayed on the display means or the direction of the actual target point The step of measuring the magnetic azimuth with the azimuth sensor, and the step of obtaining the declination based on the true azimuth and the magnetic azimuth. In the present invention, when a line connecting the current position and the target point or its direction (for example, an arrow) is displayed on the display means, and the direction of the line or the direction and the actual target point are matched, the direction on the map is changed. The actual azimuth (true azimuth) matches. In this state, the azimuth on the map coincides with the true azimuth, and the declination can be obtained by calculating the difference between the true azimuth and the magnetic north of the azimuth sensor. Since the declination is obtained in this way, a complicated calculation formula for obtaining the declination is unnecessary, and therefore maintenance of the calculation formula is also unnecessary.

(2) In the azimuth detecting method according to another aspect of the present invention, in the azimuth detecting method according to (1), at least one of the target point and the current position is displayed on the display means. Specify and set the position on the map image.

(3) In the azimuth detecting method according to another aspect of the present invention, in the azimuth detecting method of the above (1), at least one of the target point and the current position is an actual corresponding position. The position is detected by the position detection device and set.

(4) In the azimuth detecting method according to another aspect of the present invention, in the azimuth detecting method of (3), the position detecting device uses a GPS system.

(5) In the azimuth detecting method according to another aspect of the present invention, in the azimuth detecting method described in (3), the position detecting device is a cell type portable telephone such as PHS.

(6) An azimuth detecting method according to another aspect of the present invention is the azimuth detecting method according to any one of (1) to (5) above.
The method includes a step of storing the deflection angle and a step of outputting a true orientation based on the output of the orientation sensor and the deflection angle.

(7) In the azimuth detecting method according to another aspect of the present invention, in the azimuth detecting method of the above (6), there is a step of displaying the true azimuth (for example, true north or true south) on a display means.

(8) In the azimuth detecting device according to another aspect of the present invention, when the display means, the azimuth sensor for detecting the magnetic azimuth, the target point and the current position are respectively set, the current position and the target are set. A line connecting the points or the direction thereof is displayed on the display means, the true azimuth is obtained based on the position coordinates of the current position and the target point, and the direction or direction of the line displayed on the display means is the actual target point. In the state in which the direction is matched, the output of the azimuth sensor is taken in, and a computing means for obtaining a declination based on the true azimuth and the output of the azimuth sensor is provided. In the present invention, the display means is a line connecting the current position and the target point or its direction (eg, arrow).
Is displayed. When the direction of the azimuth detecting device is adjusted to match the direction of the line displayed on the display means or the direction with the actual target point, the azimuth on the map coincides with the actual azimuth.
In the state where the azimuth on the map and the actual azimuth (true azimuth) match, the deviation angle is obtained by calculating the difference between the true azimuth and the magnetic sensor, for example, magnetic north. Since the declination angle is obtained in this way, a complicated calculation formula for obtaining the declination angle is unnecessary, and therefore maintenance of the calculation formula is also unnecessary.

(9) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device of the above (8), further comprising operating means for inputting various operations, and the computing means is the operating means. The output of the azimuth sensor is fetched based on the operation input of. In the present invention, the direction of the azimuth detecting device is adjusted by the user when the operation input of the operation means is made, and the direction of the line displayed on the display means or the direction and the direction of the actual target point are Assuming that the two coincide with each other, the output of the direction sensor at that time is fetched.

(10) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device of the above (9), further comprising storage means for storing map data, and the computing means based on the map data. Display the map image on the display means,
When the position on the map image is specified by the operation of the operation means, the position is determined from the target point and the current position,
It is set as at least one of the positions.

(11) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device according to (9), further comprising position detecting means, and the computing means outputs the output of the position detecting means to the target. At least one of the point and the current position is captured and set.

(12) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device according to the above (11), wherein the position detecting device uses a GPS system.

(13) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device according to the above (11), wherein the position detecting device is a cell type portable telephone such as PHS.

(14) An azimuth detecting device according to another aspect of the present invention is the azimuth detecting device according to any one of the above (8) to (13), further comprising storage means for storing the deviation angle, and the computing means is the The true azimuth is obtained based on the output of the azimuth sensor and the deflection angle.

(15) In the azimuth detecting device according to another aspect of the present invention, in the azimuth detecting device of the above (14), the calculating means displays the true azimuth (eg true north, true south) on the display means. Display it.

(16) A navigation device according to another aspect of the present invention incorporates the azimuth detecting device according to any one of (8) to (15).

(17) In the navigation device according to another aspect of the present invention, in the navigation device according to (16), when the destination and the current position are respectively set, the present position and the target position are set. The angle γ formed by the line connecting the ground and the true azimuth is determined, the true azimuth is determined based on the output of the azimuth sensor and the declination, and the direction to the destination is determined based on the angle γ and the true azimuth. Obtained and displayed on the display means.

(18) A portable device according to another aspect of the present invention incorporates the azimuth detecting device according to the above (8) to (15).

(19) A portable device according to another aspect of the present invention incorporates the navigation device of (16) or (17).

(20) A program according to another aspect of the present invention causes a central processing unit to perform the processing of the calculation means of the azimuth detecting apparatus according to any one of (8) to (15).

(21) A program according to another aspect of the present invention causes a central processing unit to perform the processing of the calculating means of the navigation device of (16) or (17).

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 is a circuit configuration diagram of a mobile device 10 according to the first embodiment of the present invention. The mobile device 10 functions as an azimuth detecting device and a portable navigation device, but in the first embodiment, it functions as an azimuth detecting device. The case will be described. The mobile device 10 includes a CPU 12, to which various key switches 14, a GPS unit 16, a geomagnetic sensor 18, a memory 20, and an azimuth display device 22 are connected. The key switch 14 includes a power switch and various buttons to be described later. A signal corresponding to the switch is input to the CPU 12 and processing corresponding to the signal is performed.

The GPS unit 16 receives a signal supplied from an artificial satellite (GPS satellite) via a GPS antenna (not shown) and calculates the received signal to determine the current position (longitude, latitude). It has a built-in circuit for the Global Positioning System (GPS) and supplies it to the CPU 12 when it detects the current position. In addition, this G
PS is a positioning system that uses satellites that cover the entire earth, and the surface of each of the satellites that orbits at an altitude of 2,183 km from the surface of the earth is the pyramid bottom. In this system, the apex of a pyramid formed by a ridge line for receiving and measuring the signal of is received as the current position of the receiving device.
The GPS satellites of this system are orbiting in 6 orbits with respect to the earth, 4 orbiting in each orbit, 24 orbiting in total.

Further, the geomagnetic sensor 18 has, for example, two magnetic sensors arranged in directions perpendicular to each other, each magnetic sensor detects the magnitude of the magnetic field, and the direction of the geomagnetism is obtained from the magnetic field detection values in both directions. And the azimuth information is supplied to the CPU 12. Further, the memory 20 stores various data such as programs for defining the operation of the CPU 12 and map data.

This map data is managed as map leaves (map pieces) divided into regions of a longitude width and latitude width of appropriate sizes according to the scale level, and each map leaf is, for example, (a). It is composed of a background layer for displaying roads, rivers, parks, etc., (b) a character / symbol layer for displaying municipalities, road names, symbols, etc., and (c) a road layer. The road layer includes link information and the like for specifying the road position, and the road is indicated by a set of vertices (nodes) represented by the coordinates of latitude and longitude, and is a part that connects two or more nodes. Is called a link. Further, this road layer includes information such as intersection information and distance between intersections. The map image displayed on the azimuth display device 22 is drawn based on a signal formed by combining layers of a plurality of map leaves (map pieces). In addition to the above map image, the azimuth display device 22 displays the true azimuth and the direction of the destination.

FIG. 2 is a flow chart showing the processing steps for obtaining the deflection angle α by the portable device 10 of FIG.
3 to 5 show the azimuth display device 22 for obtaining the deflection angle.
It is a transition diagram of the screen of. In addition, in FIG. 3 to FIG.
The A button 24a is a button for measuring the position, the B button 24b is a button for measuring the azimuth, and the C button 24.
c is a button for setting a destination.

(S11) The CPU 12 reads the map data from the memory 20 and displays the map image on the azimuth display device 22. The user designates a specific point on this map image and sets it as the target point A. This setting is made by the user operating an appropriate key switch 14,
When the setting is made, the CPU 12 inputs the position information (latitude / longitude) of the target point A. Alternatively, the user may actually go to the target point A and operate the A button 24a to measure the position of that point (target point A). In that case, the position measurement is performed by the GPS unit 16, and C
The PU 12 captures the output of the GPS unit 16 at the time when the user operates the A button 24a.

(S12) The CPU 12 measures the position of the current position B. This position measurement is performed by the GPS unit 16, and the CPU 12 captures the output of the GPS unit 16 at the time when the user operates the A button 24a.

(S13) The CPU 12 obtains the angle β formed by the true north with the line B-A connecting both points based on the position information of the points A and B. FIG. 3 shows the screen of the azimuth display device 22 at this time. In this case, the CPU 12 first obtains true north from the position information of the points A and B. Furthermore,
The angle β formed by the line B-A and true north is obtained from the position information of the points A and B.

(S14) Point A, B on the direction display device 22
The portable device 10 is rotated while displaying the positional relationship between the point and true north, and the directions of the target point A on the screen and the actual target point A are matched. FIG. 4 shows the screen of the azimuth display device 22 at this time. On the extension of the B-A line, the actual target point A
Is located. At this stage, true north on the map image coincides with true north (true direction) as the actual direction.

(S15) The user operates the B button 24b to measure magnetic north. The magnetic north is measured by the geomagnetic sensor (orientation sensor) 18, and the CPU 12
Captures the output of the geomagnetic sensor 18 at the time when the user operates the B button 24b.

(S16) The CPU 12 controls the azimuth display device 2
2 displays the direction of magnetic north with reference to the current position B on the screen.

(S17) The CPU 12 controls the azimuth display device 2
The declination α is calculated from the relationship between true north and magnetic north (output of the geomagnetic sensor 18) on the map image displayed in 2.

FIG. 5 shows the above processing (S15) to (S1).
7 shows a screen of the azimuth display device 22 in the process of 7), and true north and magnetic north are displayed in a state where the directions of the target point A and the actual target point A on the screen are matched. .

(S18) The CPU 12 stores in the memory 20 the deflection angle α obtained as described above.

When the argument α is obtained as described above,
As the subsequent processing, the CPU 12 obtains the true north azimuth based on the output of the geomagnetic sensor 18 and the deflection angle α and displays it on the azimuth display device 22.

In the first embodiment, the declination is obtained as described above, and therefore the declination can be obtained even if the declination data corresponding to the latitude / longitude is not held in the apparatus body. . In the conventional method, if the calculation formula for obtaining the declination from the latitude and longitude is held in the device body, the declination data changes because it changes with the year, and the magnetic pole changes with the calculation formula. However, such a need is not necessary in the first embodiment. Even if the geomagnetism is out of order (or if the geomagnetism is slightly different from the surroundings), for example, the geomagnetic sensor 18
Even if is affected by magnetism such as the case (housing), the declination angle is calculated in relation to true north and magnetic north at that point. Finding true north does not cause an error. Further, when a highly accurate declination is obtained, true north calculated from magnetic north obtained from the geomagnetic sensor also becomes highly accurate. Further, when used in different environments or regions (for example, foreign countries), the declination angle may be obtained according to it, so that it can be used worldwide.

Embodiment 2. An example in which the mobile device of FIG. 1 is made to function as a mobile navigation device will be described as a second embodiment of the present invention. It is assumed that the memory 20 shown in FIG. 1 stores the declination α obtained in the first embodiment.

FIG. 6 is a flow chart showing the processing steps when navigating to the destination point C using the above-described argument α. 7 and 9 are transition diagrams of the screen of the azimuth display device 22 at that time, and FIG. 8 is an explanatory diagram of the calculation when obtaining the direction to the destination point C.

(S21) The CPU 12 reads the map data from the memory 20 and displays the map image on the azimuth display device 22. When the user operates the appropriate key switch 14 to specify the target position and operates the C button 24c while the map image is displayed, the CPU 12 takes the position as the destination C point.

(S22) The position of the present position B is measured. This position measurement is made by the GPS unit 16,
The CPU 12 captures the output of the GPS unit 16 when the user operates the A button 24a. FIG. 7 shows the screen of the azimuth display device 22 at this time, and the current position B point and the destination C point are displayed on the screen.

(S23) The CPU 12 obtains the angle γ with true north based on the position information of the points C and B. (S24) Magnetic north is measured. The magnetic north is measured by the geomagnetic sensor (direction sensor) 18, and the CPU 12
The output of the geomagnetic sensor 18 at the time when the user operates the B button 24b is captured.

(S25) The CPU 12 reads the declination α stored in the memory 20 to find the true north. True north is obtained by adding the declination α to the magnetic north direction. (S26) The CPU 12 displays the calculated true north on the screen of the azimuth display device 22. At this time, the map image displayed on the azimuth display device 22 is rotated according to the true north azimuth to match the actual azimuth with the azimuth of the map. (S27) The CPU 12 causes the azimuth display device 22 to display the direction of the destination point C from the angle γ formed with true north.

FIG. 8 is an explanatory view showing the relation between magnetic north, true north and destination C point. The direction connecting the points B and C is found in relation to magnetic north, and the angle θ formed by the magnetic north from the point B and the destination point C is found by θ = α + γ.

9A and 9B are screens when the direction of the destination point C is displayed on the azimuth display device 22. Destination C
The direction of the point is indicated by the navigation arrow 25. Since the arrow 25 is based on magnetic north (or true north), as shown in FIGS. 9 (A) and 9 (B), even if the orientation of the mobile device 10 is changed, the correct direction with respect to the destination point C is set. Can be displayed.

(S28) The CPU 12 determines whether or not to continue the above display, and continues if there is no particular end instruction. (S29) The CPU 12 determines whether or not the user has moved. If the user has moved, the process proceeds to the above process (S22), and if not, the process proceeds to the above process (S24). Note that the CPU 12 determines whether or not the user has moved based on whether or not the output of the GPS unit 16 has changed, and when the process (S24) is entered, the B button 24b is used. It is assumed that the process is automatically performed even if the person does not operate it, and the processes (S24) to (S27) are automatically repeated. Further, even when the process proceeds to the process (S22), the process is automatically performed without the user operating the A button 24a, and the processes (S22) to (S23) are automatically performed.

In the second embodiment, the true north is calculated with high accuracy by using the declination angle obtained with high accuracy in the above-described first embodiment, and the latitude / longitude representing the position has the true azimuth. Since it becomes the reference, it is possible to indicate the correct direction of the destination by knowing the direction of true north with high accuracy.

Embodiment 3. In the above-described first embodiment, an example in which the GPS unit is used as the position detecting means has been described, but for example, D (Differential) -GPS
A cell type mobile phone such as PHS or PHS may be used.

Embodiment 4. Further, in the above-described first embodiment, an example in which the current position B point is calculated by the GPS unit has been described, but the current position on the map image may be specified and the current position may be calculated from the map data.

Embodiment 5. In addition, the above-described first and second embodiments
Is based on an azimuth detecting device and a portable navigation device, but the present invention can be similarly applied to various portable devices such as PHS, mobile phones, and personal digital assistants.

[0056]

As described above, according to the present invention, the true north is obtained based on the current position and the position coordinates of the target point, and the line connecting the current position and the target point or the direction thereof is displayed on the display means.
When the direction of the line or the direction of the direction and the direction of the actual target point are matched, the direction on the map matches the actual direction (true direction), and the difference between the true direction and the output of the direction sensor in this state. Since the declination angle is obtained by calculating, the complex calculation formula for obtaining the declination angle is unnecessary, and therefore the maintenance of the calculation formula is also unnecessary.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a mobile device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a processing procedure for obtaining a deviation angle α by the mobile device of FIG.

FIG. 3 is a transition diagram (part 1) of a screen of the azimuth display device when obtaining a deviation angle in the mobile device of FIG. 1.

4 is a transition diagram (part 2) of the screen of the azimuth display device when the declination is obtained in the portable device of FIG.

5 is a transition diagram (part 3) of the screen of the azimuth display device when the declination is obtained in the mobile device of FIG.

FIG. 6 is a flowchart showing a processing process when navigating to a destination in the second embodiment of the present invention.

FIG. 7 is a transition diagram (part 1) of the screen of the azimuth display device when navigating to the destination.

FIG. 8 is an explanatory diagram of a calculation for obtaining a direction to a destination.

FIG. 9 is a transition diagram (part 2) of the screen of the azimuth display device when navigating to the destination.

[Explanation of symbols]

10 mobile devices 12 CPU 14 key switch 16 GPS unit 18 Geomagnetic sensor 20 memory 22 Direction display 24a button A 24b Button B 24c Button C 25 arrows

Claims (21)

[Claims] 1. A step of setting a target point and a current position respectively, a step of obtaining a true azimuth based on the position coordinates of the current position and the target point, and a line connecting the current position and the target point or a line thereof. Displaying the direction on the display means, matching the direction of the line displayed on the display means or the direction to the direction of the actual target point, measuring the magnetic direction with a direction sensor, and the true direction And a step of obtaining a declination based on the magnetic azimuth, the azimuth detecting method. 2. The azimuth detecting method according to claim 1, wherein at least one of the target point and the current position is set by specifying a position on the map image displayed on the display means. 3. The azimuth detecting method according to claim 1, wherein at least one of the target point and the current position is detected and set by a position detecting device at an actually applicable position. 4. The direction detecting method according to claim 3, wherein the position detecting device uses a GPS system. 5. The azimuth detecting method according to claim 3, wherein the position detecting device is a cell type mobile phone such as a PHS. 6. The method according to claim 1, further comprising a step of storing the deflection angle and a step of outputting a true orientation based on the output of the orientation sensor and the deflection angle. Direction detection method. 7. The azimuth detecting method according to claim 6, further comprising the step of displaying the true azimuth on a display means. 8. A display means, a direction sensor for detecting a magnetic direction, and a target point and a current position are respectively set, and a line connecting the current position and the target point or its direction is displayed on the display means. The true orientation is obtained based on the current position and the position coordinates of the target point, and the output of the orientation sensor is obtained in a state where the direction or direction of the line displayed on the display unit matches the actual direction of the target point. An azimuth detecting apparatus comprising: a calculation unit that takes in and obtains a deviation angle based on the true azimuth and an output of the azimuth sensor. 9. The azimuth according to claim 8, further comprising operation means for inputting various kinds of operation, wherein the computing means fetches an output of the azimuth sensor based on an operation input of the operation means. Detection device. 10. A storage unit storing map data, wherein the calculation unit displays a map image on the display unit based on the map data, and a position on the map image is specified by an operation of the operation unit. 10. The azimuth detecting device according to claim 9, wherein the position is set as at least one of the target point and the current position. 11. A position detecting means is provided, and the calculating means captures and sets the output of the position detecting means as at least one of the target point and the current position. Item 9. The azimuth detecting device according to item 9. 12. The azimuth detecting device according to claim 11, wherein the position detecting device is a device utilizing a GPS system. 13. The azimuth detecting device according to claim 11, wherein the position detecting device is a cell type mobile phone such as a PHS. 14. A storage unit for storing the deflection angle,
14. The azimuth detecting apparatus according to claim 8, wherein the computing unit obtains a true azimuth based on the output of the azimuth sensor and the deviation angle. 15. The azimuth detecting device according to claim 14, wherein the computing means causes the display means to display the true azimuth. 16. A navigation device having the azimuth detecting device according to claim 8 built therein. 17. When the destination and the current position are respectively set, the calculation means obtains an angle γ formed by a true azimuth and a line connecting the current position and the destination, and outputs the output of the azimuth sensor and The true azimuth is calculated based on the declination, and the angle γ
And a direction to the destination is obtained based on the true direction and displayed on the display means.
The described navigation device. 18. A mobile device having the azimuth detecting device according to claim 8 built therein. 19. A portable device having the navigation device according to claim 16 or 17 built therein. 20. A program for causing a central processing unit to perform the processing of the calculating means of the azimuth detecting apparatus according to any one of claims 8 to 15. 21. A program for causing a central processing unit to perform the processing of the arithmetic means of the navigation device according to claim 16.