JPH06160107A - Navigation device - Google Patents

Abstract

PURPOSE:To provide a navigation device in which the constitution is simple, additional installation is allowable and own position data can be easily obtained when a GPS receiver is unable to receive. CONSTITUTION:A system controller 5 conducts control of a whole navigation device based on an azimuth data, traveling distance data and GPS position measuring data. When a present position data PGPS can be outputted, a first and a second switch S1, S2 are connected to a terminal T1 side and the data PGPS and a present position data PGPS are used so as to control a display unit to display a present position on a display. When the data PGPS can not be outputted, switches S1, S2 are connected to a terminal T2 side, the azimuth data theta from an earth magnetism sensor and the traveling distance data from a traveling distance sensor are added by adopting the data PNOW as a reference position, outputted as a present position interpolation data PC, inputted again into the controller 5 and used as a next present position data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device, and more particularly to a display device for an on-vehicle navigation device.

[0002]

2. Description of the Related Art Conventionally, GPS has been used as a positioning device utilizing artificial satellites for various moving bodies such as automobiles, airplanes and ships.
(Global Positioning System) Navigation devices have been developed. This GPS navigation device normally receives positioning radio waves from three or more GPS satellites and
The pseudo-range data including the time offset of the receiver between the PS satellite and the receiving point (self position), the position data of each GPS satellite, and the current position (data) of the receiving point are obtained.

As a mode of using this GPS navigation device as an actual navigation device, from the simple one showing the latitude and longitude of the current position by numbers, the CRT (Ca
There is an advanced one that displays various data such as self-position and distance moving speed to the destination on the map screen displayed on the screen of thode Ray Tube).

A navigation device for displaying various data on a CRT screen reads out map data including the calculated current position from a storage medium such as a CD-ROM and uses the read map data and the calculated current position data. Performs map matching, creates screen data, and CRT
The current position, traveling direction, etc. of the self are displayed on the map screen of. From this display image, the user can grasp his / her current position in association with the map.

Map matching will be described below. The digitized map data includes the information about the inclination of the line segment and the direction and distance as the length. The method of estimating the accurate current position by using the information on the azimuth and distance is called map matching. By this map matching, if it is determined that there is a high possibility that the current position is on the road on which the vehicle has been traveling, even if the detected heading is slightly shifted due to an error in the sensor, the current position is corrected to the road. Therefore, it is possible to perform a display or the like without any discomfort.

[0006]

By the way, since the above-mentioned conventional GPS navigation device performs positioning by receiving radio waves from an artificial satellite, positioning is performed in a tunnel, behind a tall building or in a grove. Since it cannot receive the radio wave for use and does not output the self-position data, it says that even though the vehicle is running, it will be in a stopped state on the screen of the display and you will not be able to know your own position. There was a problem.

In order to solve this, a self-standing sensor such as a vehicle speed sensor which is mounted on a crankshaft of an automobile and outputs a pulse according to the number of revolutions of the crankshaft is provided, and self-position data can be obtained by a GPS receiver. If there is no such sensor, there is a method that interpolates this. However, the additional installation of such a self-supporting sensor has a problem that it is difficult to install it compared with the case where it is installed from the beginning.

Therefore, an object of the present invention is to provide a navigation device which has a simple device configuration, can be easily installed additionally, and can easily obtain self-position data even when the GPS receiver cannot receive the data. .

[0009]

In order to solve the above-mentioned problems, the present invention provides a GPS positioning means for receiving positioning radio waves from GPS satellites and outputting self-position data of a mobile body.
Storage means for storing map data, map matching means for performing map matching based on the self-position data and the map data, and outputting current position display data, display means for displaying various information, and the map data A navigation device that displays a map on the display means based on the display means and displays the self-position of the moving body on the map display based on the current position display data. A moving distance sensor that detects the wind speed near the moving body and outputs moving distance data corresponding to the moving distance of the moving body, and a direction sensor that detects the moving direction of the moving body and outputs the moving direction data. , When self-positioning of the GPS positioning means is impossible, self-position interpolation data is obtained based on the moving distance data and the traveling direction data. It is configured to include an arithmetic unit for outputting the self-position interpolation data as the location data.

[0010]

According to the present invention, the moving distance sensor detects the wind speed in the vicinity of the moving body due to the movement of the moving body, and outputs moving distance data corresponding to the moving distance of the moving body to the calculating means.
Further, the direction sensor detects the traveling direction of the moving body and outputs traveling direction data to the arithmetic means.

As a result, the calculating means obtains the self-position interpolation data based on the moving distance data and the traveling direction data when the GPS positioning means cannot measure the position, and outputs the self-position interpolation data as the self-position data.

Therefore, even when the GPS positioning means cannot perform positioning, the navigation device can display the self-position on the display means based on the self-position interpolation data by the computing means. Further, the moving distance sensor and the direction sensor can be easily installed additionally.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing a basic configuration when the present invention is applied to a vehicle-mounted navigation device.

The on-vehicle navigation device 100 includes a geomagnetic sensor 1 which outputs direction data of the traveling direction of the vehicle,
A GPS receiver 2 that receives radio waves from GPS satellites and outputs GPS positioning data, and a mileage sensor 3 that has a propeller and detects the wind speed associated with the traveling of the vehicle by the number of revolutions of the propeller and outputs mileage data. , A system controller 5 that controls the entire navigation device based on azimuth data, mileage data, and GPS positioning data, an input device 11 for inputting various data, and a CD-ROM under the control of the system controller 5. A CD-ROM drive 12 for reading out and outputting various data such as map data from the disk DK, and a display unit 1 for displaying various display data under the control of the system controller 5.
3 is provided.

The system controller 5 includes an interface section 6 for interfacing with the outside, a CPU 7 for controlling the entire system controller 5, a ROM 8 in which a control program for controlling the system controller 5 is stored, and a nonvolatile memory (not shown). RAM 9 which has a unit and stores various data in a rewritable manner. The input device 11, the CD-ROM drive 12 and the display unit 13 are connected to each other via a bus line 10.

The display unit 13 comprises a graphic controller 14 for controlling the entire display unit 13 based on control data sent from the CPU 7 via the bus line 10 and a memory such as VRAM (Video RAM) for immediate display. A buffer memory 15 for temporarily storing possible image information, a display controller 16 for controlling display of a display 17 such as a liquid crystal display device or a CRT based on image data output from the graphic controller 14,
It is configured with.

FIG. 2A shows an example of the appearance of the traveling distance sensor 3. The mileage sensor 3 is connected to the GPS receiver 2 to receive radio waves from GPS satellites.
It is provided in a wind tunnel 3A formed integrally with the PS antenna 2A. The GPS antenna 2A is usually attached to the outside of the ceiling of the automobile. It should be noted that the mounting position of the traveling distance sensor 3 with a GPS antenna may be a position capable of receiving positioning radio waves from GPS satellites and detecting the wind speed associated with the traveling of the vehicle.

As shown in FIG. 2 (b), the main body of the traveling distance sensor 3 is attached to a propeller 20 which is rotated by wind pressure in the vicinity of the own vehicle generated as the vehicle travels, and a rotary shaft 20S of the propeller 20. Magnet M and fixed shaft 20FS
Of the magnetoresistive element (MR element) in the portion facing the magnet M of
An MR or Hall element H is provided.

As a result, the propeller 20 is rotated by the wind pressure generated by the traveling of the vehicle, and the magnet M attached to the rotating shaft 20S is rotated. The magnetic field that changes with the rotation of the magnet M is detected by the MR element MR or the Hall element H, and a pulse corresponding to the rotation speed is output from the travel distance sensor 3. Therefore, the traveling distance can be calculated by integrating the number of pulses.

Next, the operation of this embodiment will be described with reference to FIGS. FIG. 3 shows a processing flowchart showing the outline operation of the present embodiment, and FIG. 4 shows a schematic block diagram for explaining the operation.

First, the system controller 5 uses the GPS
It is determined whether the receiver 2 can receive, that is, whether the GPS receiver 2 can output the current position data P _GPS (step S1).

The GPS receiver 2 displays the current position data P _GPS
If the current position data P _GPS of the GPS receiver 2 is output, the system controller 5 updates the current position (step S4). More specifically, the system controller 5 connects the first switch S ₁ and the second switch S ₂ to the terminal T1 side, so that the system controller 5 as the position determining means can operate the GPS receiver 2
Using the current position data P _{GP S} of the current position data P _NOW
The display unit 13 is controlled to display the current position on the display 17.

The GPS receiver 2 displays the current position data P _GPS
If it cannot output, the running vector is calculated using the self-standing sensor (step S2), and the current position data P _NOW (= position vector) obtained by the current position data P _GPS output by the GPS receiver 2 last time is calculated. Addition is performed to obtain the current position interpolation data P _C (step S3).

[0024] Specifically, the first switch S ₁ and the second switch S ₂ is connected to the terminal T2 side reference position a current position data P _{NO W} corresponding to the current position data P _GPS of the last GPS receiver 2 As the azimuth data θ from the geomagnetic sensor 1 and the travel distance data D _RUN of the travel distance sensor 3 are added, the current position interpolation data P _C is output,
It is input again to the system controller 5 functioning as a position determining means and used as the next current position data.

As described above, according to this embodiment,
Even when GPS cannot be received, the current position data can always be obtained by the mileage sensor having a simple structure. Further, since the mileage sensor of the present embodiment is configured to detect the wind pressure due to the traveling of the automobile to obtain the mileage, additional installation can be easily performed without any modification to the mechanism of the automobile body. Similarly, a geomagnetic sensor, which is a direction sensor, can be easily installed additionally.

In the above embodiments, the geomagnetic sensor was used as the direction sensor, but it is possible to use a gyro, a wheel speed difference sensor or the like.

[0027]

According to the present invention, the navigation device can display the self-position on the display means based on the self-position interpolation data by the calculating means even when the GPS positioning means cannot measure the position, and the navigation device is always available. It becomes possible to obtain the current position data. Further, since the moving distance sensor is configured to detect the wind speed in the vicinity of the moving body due to the movement of the moving body and output moving distance data corresponding to the moving distance of the moving body, it only needs to be attached to the moving body. Can be installed, and additional installation can be done without any modification to the mechanism of the mobile body.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a navigation device.

FIG. 2 is an explanatory diagram of a travel distance sensor.

FIG. 3 is an operation flowchart of the embodiment.

FIG. 4 is an operation explanatory diagram of the embodiment.

[Explanation of symbols]

 100 ... In-vehicle navigation device 1 ... Geomagnetic sensor 2 ... GPS receiver 2A ... GPS antenna 3 ... Distance sensor 3A ... Wind tunnel 5 ... System controller 6 ... Interface section 7 ... CPU 8 ... ROM 9 ... RAM 10 ... Bus 11 ... Input Device 12 ... CDROM drive 13 ... Display unit 14 ... Graphic controller 15 ... Buffer memory 16 ... Display control unit 17 ... Display 20 ... Propeller 20S ... Rotating shaft 20F ... Fixed shaft M ... Magnet MR ... Magnetic resistance H ... Hall element

Claims (1)

[Claims] 1. GPS positioning means for receiving positioning radio waves from GPS satellites and outputting self-position data of a mobile body,
Storage means for storing map data, map matching means for performing map matching based on the self-position data and the map data, and outputting current position display data, display means for displaying various information, and the map data A navigation device having a map display on the display means based on the display means, and a display control means displaying the self-position of the moving body based on the current position display data on the map display. A moving distance sensor that detects a wind speed in the vicinity of the moving body, and outputs moving distance data corresponding to the moving distance of the moving body, and a direction sensor that detects a moving direction of the moving body and outputs moving direction data. , When the positioning by the GPS positioning means is impossible, self-position interpolation data is obtained based on the moving distance data and the traveling direction data. Because, the navigation apparatus characterized by comprising a calculating means for outputting the self-position interpolation data as the location data.