JP3238538B2 - Car navigation system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle navigation system.

[0002]

2. Description of the Related Art A navigation system which displays the current position of a vehicle on a map displayed on a display device and assists driving is a GPS system which determines the position of the vehicle based on radio waves from artificial satellites. A sign post method for recognizing the position of the own vehicle based on position data from a sign post installed on the side of the road; There is a completely autonomous traveling system in which the position of a car is calculated and determined, and there is a mixed autonomous traveling system in which the vehicle position is determined. In the navigation system of the autonomous driving system, the navigation system (program) has a large storage capacity occupied by the navigation system, and is therefore stored together with a navigation map database on a CD-ROM having a large storage capacity.

[0003]

SUMMARY OF THE INVENTION A CD-RO having a large storage capacity includes an execution program of a navigation system as described above together with a navigation map database.
In the navigation device stored in the M, the program stored in the CD-ROM is read into the internal memory after the vehicle starts, and the physical values are set by the time the navigation device is actually started after the initial values and the like are set. Therefore, as shown in FIG. 2, the navigation system does not operate in the section A where the navigation system (program) starts from the point 21 where the power of the navigation device is turned on, as shown in FIG. In the meantime, since the starting point of the navigation system is the calculated starting point in spite of the fact that the starting point is the point 21 in the meantime, the distance of the section A until the navigation device is started is not calculated. Positioning is not performed, and there is a problem that navigation accuracy cannot be maintained.

[0004] The present invention has been made in view of the above problems, and a power supply of an autonomous navigation device is turned on.
It is an object of the present invention to provide a navigation device capable of realizing accurate navigation immediately after the navigation.

[0005]

According to a first aspect of the present invention, there is provided an on-vehicle navigation device, comprising: a first storage unit storing a navigation system executing unit;
When the power is turned on storing the simple navigation processing execution means,
A nonvolatile storage unit that can be read almost simultaneously, and a control unit that controls execution of the navigation system execution unit.
In the vehicle-mounted navigation device having the above, the control unit starts the execution preparation of the navigation system execution means stored in the first storage unit by turning on a power source , and executes the simple navigation of the nonvolatile storage unit.
And executing navigation processing by the navigation system executing means to display a map when the navigation system executing means is ready for execution.

According to a second aspect of the present invention, in the vehicle-mounted navigation device according to the first aspect, the control unit controls the preparation of the navigation execution by the navigation system executing means and the execution of the simple navigation processing executing means in parallel. And

According to a third aspect of the present invention, in the vehicle-mounted navigation device according to the second aspect, the simple navigation processing executing means determines and updates at least the position of the own vehicle.

[0008]

With the above arrangement, the vehicle-mounted navigation device according to the present invention executes the simple navigation processing execution means when the power is turned on, and performs the navigation processing when the navigation system execution means is ready to execute the navigation, thereby displaying the map. indicate.

[0009]

FIG. 1 is a block diagram showing a configuration of an embodiment of a navigation apparatus according to the present invention. FIG. 2 is an explanatory diagram showing a relationship between activation of a navigation system accompanying driving of a car and a simplified navigation system. FIG. 3
2 is a flowchart showing the operation of the navigation device in FIG.

In FIG. 1, 1 is a distance sensor, 2 is an azimuth sensor, 3 is a GPS receiver for receiving radio waves from artificial satellites and demodulating position data (latitude and longitude) signals, and 4 is a simple navigation system. Program to execute (simple
A ROM that stores navigation processing executing means (hereinafter, referred to as a simple program (described later)) corresponds to a non-volatile storage unit. Reference numeral 5 denotes a navigation program (navigation executing means (hereinafter, main program) and map data). A CD-ROM stored therein corresponds to the first storage unit 6. A display for displaying a map, a display sign, and the like based on a result of the navigation processing corresponds to the display unit, and 7 is an execution control of the navigation system. And a CPU that controls the entire apparatus and corresponds to a control unit.

In FIG. 1, a CPU 7 has a power supply (not shown)
If N, an internal memory (not shown) of a main program for operating the navigation device from the CD-ROM 5
Start loading (loading) to. At this time,
As shown in FIG. 2, after the vehicle 20 starts, the CD-RO
After the main program stored in M5 is read into the internal memory and the initial values are set, it takes some physical time (about 10 seconds in actual measurement) until the navigation device can be started. Therefore, the navigation system does not operate until the start of the navigation device preparation and the start thereof (section A). However, in the section A, when the power is turned on, the CPU 7 sets the navigation device in parallel with the start preparation of the navigation device. To read the simple program stored in the ROM 4 and execute the simple navigation system.

In the simple navigation system, specifications required for navigation, for example, a traveling distance and a direction of the own vehicle are calculated until the navigation device is activated. In the embodiment, the simple navigation system is constituted by a program and stored in the ROM 4, which is a nonvolatile storage unit, so that it can be executed almost simultaneously with turning on the power. In addition, since the vehicle position can be determined from the sensors 1 and 2,
The S receiver 3 is not essential.

Next, when the preparation for starting the navigation device is completed, the CPU 7 shifts the control from the execution of the auxiliary system to the execution of the main system in order to immediately start the execution of the navigation system. In FIG. 2, it is assumed that the preparation for starting the navigation device is completed at the point 22. After this point (section B), the navigation system is executed. In this case, the specifications (distance, direction, etc.) obtained by the simple navigation system are taken over by the main system. The simple processing executing means for executing the simple navigation system is constituted by a program in the embodiment, but may be constituted by hardware (electronic circuit).

The operation of the navigation device of FIG. 1 will be described below with reference to FIGS. 3 (a) and 3 (b). FIG. 3 (a)
[S1] The car starts and the power of the navigation device is turned on. [S2] The CPU 7 reads the simple program stored in the ROM 4, executes the simple navigation system, and starts simple autonomous traveling (see FIG. 3B). [S3] The CPU 7 executes the CD-R in parallel with the execution of the simple navigation system in step S2 by parallel processing.
With the navigation device in an activated state, such as reading the main program from the OM into the internal memory, warming of the display device, and the like, preparation for activation for actually performing navigation is performed.

[S4] Unless the preparation for activation is completed, step S3
Then, the simple autonomous traveling and the preparation for starting the navigation device (parallel processing) are repeated. [S5] The navigation device is activated, and the main program is used to obtain the latitude, longitude, and distance data and direction data from the distance sensor 1 and the direction sensor 2 obtained from the GPS receiver 3 and the map from the CD-ROM device 5 according to the main program. High-precision autonomous driving (navigation system) that performs navigation processing based on data and displays a map is started.

Next, the simple navigation system processing of FIG. 3B will be described. [S21] The distance sensor and the direction sensor are adjusted. [S22] The CPU 7 reads distance data (digital data) from the distance sensor. [S23] The CPU 7 reads azimuth data (digital data) from the azimuth sensor.

[S24] The traveling distance and the traveling direction are calculated from the read distance data and the azimuth data, and the autonomous position is updated. [S25] While the preparation for starting the navigation device is not completed, the process returns to step S22, and the simple autonomous traveling and the preparation for starting the navigation device (parallel processing) are repeated. [26] The CPU 7 ends the simple autonomous traveling and shifts the control to the execution of the navigation system.

As described above, since the simple navigation system can be configured as a simple program, it can be stored in a small-capacity ROM, and can autonomously run immediately after power-on. In the embodiment, when the simple processing execution means for executing the simple navigation system is constituted by a program, the program is stored in the ROM. However, the program is not limited to the ROM, and may be read out almost at the same time when the power is turned on. For example, S-RAM) may be used.

[0019]

As described above, according to the navigation device of the present invention, autonomous traveling can be performed immediately after the power is turned on. Therefore, accurate navigation can be performed immediately after the power is turned on in the autonomous navigation device. Can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a navigation device according to the present invention.

FIG. 2 shows activation of a navigation system (hereinafter, referred to as a main system) associated with driving of a car and simple navigation.
It is explanatory drawing which shows the relationship with a system.

FIG. 3 is a flowchart illustrating an operation of the navigation device in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Distance sensor 2 Orientation sensor 3 GPS receiver 4 ROM (2nd storage part) 5 CD-ROM 6 Display (display part) 7 CPU (processing part)

Claims (3)

(57) [Claims] 1. A first storage unit storing a navigation system execution unit, a non-volatile storage unit storing a simplified navigation processing execution unit and readable almost at the same time as power is turned on, and execution of the navigation system execution unit. A control unit for controlling the operation of the navigation system execution unit stored in the first storage unit by turning on a power supply , and starting the execution of the nonvolatile system. simple Na of the storage unit
The navigation system executes navigation by the navigation execution processing means, and when the navigation system execution means is ready for execution, the navigation system execution means
An in-vehicle navigation device characterized in that a navigation process is carried out by a computer to display a map. 2. The in-vehicle navigation device according to claim 1, further comprising: a control unit configured to execute a navigation execution preparation and a simple navigation by the navigation system execution unit.
Vehicle navigation apparatus characterized by parallel control the execution of the Deployment process execution means. 3. The in-vehicle navigation device according to claim 1, wherein the simple navigation processing execution means determines and updates at least the position of the own vehicle.