JP2002350145A - Method and apparatus for present position detection for navigation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid detecting wrong present position when a power source of a navigation device is temporarily cut during guiding and restarted and then moving is initiated immediately before the ending of activation process of a main processor. SOLUTION: A vehicle position detector 26 detecting the position of a vehicle by a GPS receiver 27 or a self-contained navigation sensor 28 using the signal of a distance sensor 29 and an angle sensor 30 executes an operation with a coprocessor other than a main processor and stores an obtained present position data into a vehicle position memory 31. Before the ending of activation process of the main processor 3 at the initiation of the navigation system, the coprocessor 25 operates the present position as stated above. The obtained data are recorded in the vehicle position memory and by repeating this, data showing the course is obtained. When the main processor started up, the present position data in the memory is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation current position detecting method and apparatus for detecting a current position in a navigation device for providing guidance along a guidance route, and more particularly, to activate a main processor of the navigation device when the navigation device is activated. The present invention relates to a navigation current position detection method and apparatus which can immediately obtain an accurate current position even when a vehicle moves before ending the processing and prevent inappropriate guidance.

[0002]

2. Description of the Related Art For example, in a vehicle navigation system, a CD-ROM storing map data for drawing a map and facility information data for retrieving facilities and the like,
A map / information storage medium such as a DVD-ROM;
A playback device that reads data from an information storage medium, a display device that displays a map, etc., a self-contained navigation device such as a distance sensor or a gyro, and a vehicle position detection that detects the current position of the vehicle and the azimuth of the traveling direction using a GPS receiver, The map data including the current position of the vehicle is read from the map / information storage medium, a map image around the vehicle position is drawn on the screen of the display device based on the map data, and the vehicle position mark is displayed. The display is superimposed on the screen and the map image is scrolled according to the movement of the vehicle, or the map image is fixed on the screen and the vehicle position mark is moved, so that the vehicle is currently traveling where It is easy to understand at a glance.

[0003] Maps such as CD-ROM and DVD-ROM
The map data stored in the information storage device is divided into longitude and latitude widths of appropriate sizes according to various scale levels, and roads and the like are coordinate sets of nodes represented by longitude and latitude. It is remembered. A road is composed of a connection of two or more nodes, and the map data displays a road layer including a road list, a node table, an intersection configuration node list, and the like, and roads, buildings, facilities, parks, rivers, and the like on a map screen. Data such as background layers and the like, and information data for displaying characters and map symbols such as administrative division names such as municipal names, road names, intersection names, and facility names.

[0004] The navigation device also has a route guidance function for enabling a user to easily travel to a desired destination without making a mistake on a road. According to this route guidance function, from the departure point to the destination, and if necessary, specifying a stopover, the most appropriate route among these routes, taking into account conditions such as time, distance, toll, etc. The route is automatically searched, the searched route is stored as a guidance route, and during driving, the guidance route is displayed on the map image in a different color from the other routes and displayed thicker, or the vehicle is guided. When approaching the intersection where the course on the route should be changed within a certain distance, the intersection is enlarged and displayed on the screen by drawing arrows etc. indicating the direction to change the course, and voice guidance for turning right and left Is performed, the user can be guided to the destination.

[0005]

In the above navigation apparatus, when the power is turned on when the navigation apparatus is used, a device driver or a navigation application in the navigation apparatus is started, and thereafter a self-contained navigation sensor such as a distance sensor or a gyro is used. Start acquiring current location information from GPS. In recent navigation systems, the OS, which is the basic software, is used to enhance various functions.
Gradually increases, and depending on the processing speed and the like of the CPU of the apparatus, it takes about 10 seconds until the application is started after the power is turned on. In such a navigation device,
Until the device driver or the application of the navigation device is activated after the power of the device is turned on, the position information obtained by the GPS or the self-contained navigation sensor such as the gyro used for determining the position of the vehicle is not acquired.

For this reason, the vehicle may move a considerable distance before the power is turned on and the above-mentioned information on the position of the vehicle can be taken in from a sensor or the like. Especially when obtaining the current position based on the information, the current position obtained first may be largely apart from the actual position.

Further, when the ignition key of the car is turned off, the power supply of the navigation device is not turned off immediately, and a shutdown process such as saving information to be stored in preparation for final power off. May be performed. Even if the ignition key is turned on again during such a shutdown process, the restart process is performed after the shutdown process is completed or after the shutdown process is interrupted.
It may take more time. Therefore, in such a case, especially, the current position first obtained may be largely apart from the actual position.

[0008] For this reason, for example, an inappropriate operation as shown in FIG. 5 may be performed. That is, it is assumed that a guidance route to the fifth elementary school is initially set as indicated by a thick line in FIG. 7A, and guidance is performed along this guidance route. At this time, stop the engine to shop at the 7-Eleven at the vehicle mark position in the figure,
When the driver leaves the car after removing the key switch, the accessory switch is turned off, and the power supply of the navigation device is also cut off as described above. Thereafter, when the user makes a short shopping and starts the engine again by the key switch, the accessory switch is turned on and the navigation device is restarted.

At this time, the user drives the car immediately, and when the main processor of the navigation device has not yet completely started up in accordance with the predetermined startup program, the user can display the screen on the screen of the navigation device. Turn right at the intersection with Chozenji Temple, and turn left at the intersection with the gas station. Suppose you were. After that, the main program of the navigation device finishes a predetermined process and starts up, calculates the current position based on the sensor information, and further performs map matching against the map,
It may be erroneously recognized that a vehicle exists at point B in the figure.

At this time, if the navigation device stores the destination and stores that the guidance route is being guided, the data is used, and if the data is not stored, the user inputs a new instruction in FIG. In some cases, a guidance route from the point B as indicated by the thick line in (b) to the fifth elementary school at the destination is set, and guidance along the route is started. It takes a lot of time to calculate the guidance route at this time,
The user is confused because the vehicle continues to travel with the wrong position indicated. When the vehicle subsequently travels, the navigation device, for example, indicates an erroneous current value up to a point C in FIG. 5C, and then detects a mismatch between the sensor signal and the map data. Is finally known and displayed.

By such processing, the navigation apparatus sets the current position of the vehicle as the point D, calculates a guidance route from this point D to the fifth elementary school at the destination again, and obtains a guidance route as indicated by a thick line in the figure. It will be. However, when this calculation takes a long time, the vehicle may continue straight ahead without making a turn at the intersection where the vehicle should turn right, and at that time, the guide route to the destination must be calculated again. As described above, when the time required for the main processor to start up is long and the vehicle travels a long distance during that time, the above-described inconvenience frequently occurs, and the navigation device must be difficult to use.

Such an inappropriate operation at the time of starting the navigation device is not limited to the navigation device mounted on the vehicle as described above. For example, the navigation program is installed in a portable information terminal or a portable personal computer, and
A similar problem occurs in a navigation device connected to a PS receiver and brought into a vehicle or the like for use.

Therefore, according to the present invention, even if the vehicle or the like travels a considerable distance after the power of the navigation device is turned on and the device driver or application of the navigation device is activated, it takes a long time. It is an object of the present invention to provide a navigation current position detection method and apparatus that can obtain accurate current position data when the start-up processing of the apparatus is completed and can provide an appropriate guidance route.

[0014]

SUMMARY OF THE INVENTION According to the present invention, there is provided a navigation current position detecting method for solving the above problems.
The current position is detected by a current position calculating means that operates separately from the main processor of the navigation device, and the current position of the vehicle detected by the current position calculating means is stored in a current position memory. This is input from the current position memory.

Further, in another navigation current position detecting method according to the present invention, the current position calculating means is performed by a coprocessor which performs processing by a calculation program or a circuit dedicated to the calculation. .

[0016] The present invention also provides a navigation current position detecting device, comprising: a sensor for outputting a signal relating to the current position; current position calculating means for calculating a current position based on the signal from the sensor; And a current position memory for storing current position data, wherein the current position calculating means operates separately from the main processor, and the main processor inputs current position data from the current position memory.

Further, in another navigation current position detecting apparatus according to the present invention, the current position calculating means is performed by a coprocessor which performs processing by a calculation program or a circuit dedicated to the calculation. .

Another navigation current position detecting device according to the present invention includes a memory for storing a current position immediately before power supply to the navigation device is cut off,
The present position at the time of restart of the navigation device is obtained based on the current position stored in the memory.

In another navigation current position detecting apparatus according to the present invention, the current position calculating section deletes calculation data within a predetermined time from the start or does not perform the calculation for a predetermined time from the start. It was made.

Further, another current position detecting device for navigation according to the present invention uses the current position detecting device for navigation in a vehicle.

[0021]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram of a navigation device to which the present invention is applied. In this navigation device, the main processor 3 connected to the main bus 1 executes various programs recorded in the ROM 4
The RAM 5 controls various functions of a large number of functional units connected to the main bus 1 as shown in the figure. The image display processing unit 6 among the functional units connected to the main bus 1 has a map, guidance route, traffic information,
Various images such as function selection displays are selectively or superimposed, and the screen is divided and displayed.

The voice output processing section 8 outputs various voices and sounds including a voice for guidance route guidance output from the speaker 9. The voice recognition processing unit 10 processes and analyzes the user's voice input from the microphone 11, and uses the processed voice as an operation instruction signal for the navigation device. The operation signal input unit 12 is connected to a remote controller 13, an operation switch 14, a touch panel 15 and the like as necessary, and serves as an operation instruction signal for the user's navigation device together with the signal from the voice recognition processing unit 10.

The traffic information input unit 16 has an FM multiplex receiver 1
7 is connected to input traffic information by VICS in a wide area, and a beacon receiver 18 is connected to input traffic information mainly on the traveling direction of vehicles on general roads and highways. In the illustrated embodiment, the map information data input section 19 uses a DVD-ROM 20 as a map / information recording medium, and selects and takes in necessary data from map data and various information data recorded on the DVD-ROM. .

DVD-RO as map / information storage medium
The map data stored in the M20 is divided into longitude and latitude widths of appropriate sizes according to various scale levels, as in the conventional case, and roads and the like are represented by longitude and latitude. Is stored as a set of coordinates of the selected node. A road is composed of a connection of two or more nodes. The map data includes a road layer including a road list, a node table, an intersection configuration node list, and the like, and roads on a map screen.
Display map data such as background layers for displaying buildings, facilities, parks, rivers, etc., and characters and map symbols such as administrative division names such as municipal names, road names, intersection names, and facility names. And information data for the purpose.

The map drawing section 21 is based on the above-described map data captured by the map / information data input section 19,
The map image data for displaying the map to be displayed on the display 7 by various display methods such as 3D display is formed, and the map image data is output to the image display processing unit 6. Also,
In the navigation device, a guide route calculation unit 22 obtains a guide route in order to allow a user to easily travel on a road to a desired destination without making a mistake.
With this route guidance function, the most appropriate route from the departure point to the destination using the map information and the route via the input via point as needed, taking into account conditions such as time, distance, fee, etc. Search automatically. In addition, the searched route is stored as a guidance route in, for example, the EEPROM 2 or the like.
During traveling, the guidance route is drawn on the map image in a different color from the other routes and displayed on the screen in a thicker manner.

In the guidance output section 23, when the vehicle approaches an intersection on which the course of the guidance route should be changed within a certain distance, the intersection is enlarged and displayed, and an arrow indicating the direction in which the course is to be changed is displayed. Is drawn and displayed on the screen, or a right or left turn is guided by a voice from the speaker 9, so that the user can be guided to the destination. In this embodiment, the main bus 1 has an accessory switch (A
CC-SW) 24 as a signal for vehicle position detection processing immediately after the accessory switch is turned on, as described later.

In the present invention, in particular, a coprocessor 25 is connected to the bus 3, and a vehicle position detector 26 and a vehicle position memory 31 such as an SRAM as a buffer in the illustrated embodiment are connected to the coprocessor 25. . The vehicle position detector 26 has a GPS receiver 27 for receiving GPS signals.
And a self-contained navigation sensor 28 composed of a distance sensor 29 and an angle sensor 30, and detects the current position of the vehicle based on these sensor signals. This vehicle position detector 26
And the coprocessor 25 that operates according to the program for performing the processing in the vehicle position detecting section corresponds to the current position calculating means of the present invention. At this time, the main processor 3
Communicates with the coprocessor by the operation of application software recorded in the ROM 4 for navigation,
An operation such as obtaining the vehicle position information calculated by the coprocessor 31 is performed.

As a result, the current position of the vehicle can be calculated by the coprocessor 23. In particular, immediately after the power is turned on, the calculated vehicle position is stored in the vehicle position memory 31 such as an SRAM. When the vehicle enters a normal operation state after the coprocessor 23, the vehicle position stored in the vehicle position memory 31 is fetched in response to a request from the main processor. This coprocessor 2
5 can be operated as software of a program recorded in the ROM 2, and A
It may be hardware composed of a dedicated circuit such as SIC. In the conventional apparatus, the entire processing including the vehicle detection processing is performed by the main processor 3, and the current position is calculated as a series of processing at the time of starting.

The calculated current position may be stored in the EEPROM 2 connected to the bus 1 or in a rewritable memory such as an SRAM instead of the vehicle position memory 31. This memory temporarily stores various data even when the power is turned off.Especially, when the user enters a convenience store during vehicle guidance route guidance, the engine is temporarily stopped and the vehicle continues running immediately afterwards. It is preferable that the guidance route, the traveling route, the vehicle position when the engine is stopped, and the like be stored in advance. In addition, when the engine is stopped while traveling along the guidance route, the time is recorded in the EEPROM 2, and when the traveling is started within a short time within a predetermined time, the travel along the preceding guidance route is performed. It is also possible to set so that the subsequent processing is performed from the position stored as traveling, and the processing is restarted from a new destination setting when a long time has elapsed.

Further, the map data in the vicinity of the current position of the vehicle is converted into a map / map based on the vehicle position signal obtained as described above.
The map is read from the DVD-ROM 20 as an information storage medium, a predetermined map is formed by the map drawing unit 21 based on the map data, and a map image around the vehicle position is drawn on the screen of the display 7. In addition, the vehicle position mark indicating the current position is superimposed on the map image and displayed, and the map image is scroll-displayed according to the movement of the vehicle, or the vehicle position mark is moved while the map image is fixed on the screen. At a glance where you are currently driving.

In the navigation device configured as described above, the accessory switch (ACC-S) of the vehicle is used.
The process of detecting the current position after turning on W) can be performed, for example, according to an operation flow as shown in FIG.
First, after detecting that the accessory switch is turned on (step S1), this operation flow is started, whereby the navigation device is started (step S2), and the coprocessor 2 including the main processor 3 in FIG.
At 5 and the like, processing starts, and various programs operate in a predetermined order.

At this time, the coprocessor 25 shown in FIG. 1 operates only for detecting the vehicle position. Therefore, even when it takes about 10 seconds, for example, for the main processor 3 to complete a number of predetermined processes at the time of startup, the coprocessor 25 starts processing the signal from the self-contained navigation sensor 28 because the power supply immediately after the startup is used. Even if the characteristics of an angle sensor such as an unstable or gyro sensor are taken into account, almost accurate calculation of the current position data can be performed in about 2 seconds, and it is possible to sufficiently cope with the movement of the vehicle immediately after starting. The data acquisition of the current position by the GPS receiver is somewhat delayed from the calculation of the current position data by the self-contained navigation sensor due to a process such as searching for a satellite to be used, but the current position data can be obtained in a few seconds. In this manner, the vehicle position is detected by the coprocessor (step S3). FIG. 3 shows an example of the vehicle position detection process performed by the coprocessor, which will be described later.

Next, the current position data obtained as a result of the vehicle position detection processing by the coprocessor as described above is
In FIG. 1, it is stored in the vehicle position memory 31 (step S4). At this time, it is possible to simply store only the current position, but it is preferable to record the history of the current position continuously as travel route data and record the travel route since the accessory switch was turned on. . After that, by performing more processing than the above coprocessor, the main processor that starts up slowly,
It is detected whether or not there is a request for output of the vehicle position. If the main processor has not been started yet, the process returns to step S3 if there is no request, and the processing for detecting the vehicle position by the coprocessor and the memory of the detected value are continued. . In addition,
When returning from step S5 to step S3,
As shown in FIG. 3, the process returns to a step in the middle of a series of processes for detecting the vehicle position by the coprocessor.

If it is determined in step S5 that the main processor has requested the output of the vehicle position,
When the current position of the vehicle and its route data are also stored from the vehicle position memory, the main processor also fetches the data. Next, it is determined whether or not the vehicle position when the accessory switch is turned off is stored in, for example, the EEPROM 2 or the like in FIG. 1 (step S7). By adding and correcting the calculated current position and the like to the data stored as described above, the current vehicle position can be accurately calculated and obtained (step S8).

On the other hand, in step S7,
When it is determined that the vehicle position at the time of the accessory switch-off is not stored, the captured vehicle position is set to the current position using only the data (step S1).
0). At this time, if the current position data has already been obtained using the GPS data, the current position data can be used as it is. However, if the GPS data has not yet been used, the GPS data has been obtained. Later, the data from the self-contained navigation sensor can be added to determine the current vehicle position.

The current position of the vehicle obtained as described above is
The current location is displayed on the map screen (step S9).
Thereafter, guidance route guidance processing is performed (step S11).
In the guidance route guidance process, when the accessory switch is turned off, if the guidance route is stored in the memory such as the EEPROM 2 as described above, the guidance is immediately provided immediately after the guidance of the preceding guidance route. However, if this is not stored, a new guidance route is calculated from the current position of the vehicle obtained as described above to the destination input separately, and the guidance is performed in the same manner as in the related art. Provides guidance along the route.

By the above-described functional configurations and their operations, the problem of the guide route guidance of the conventional navigation device shown in FIG. 5 can be solved, for example, as shown in FIG. That is, FIG.
As in (a), the state where the accessory switch is turned off by stopping the engine and temporarily removing the key to temporarily stop at Seven-Eleven while traveling along the guidance route is shown in the figure. Is completed, the engine of the car is started, and the vehicle is immediately driven. Since the accessory switch is turned on at the same time when the engine is started, the coprocessor immediately calculates the moving distance and direction of the car from the point where the accessory switch is turned on by the distance sensor and the angle sensor, and calculates the vehicle position. Store in memory.

As a result, FIG. 4 (b) is stored in the vehicle position memory.
The travel route of the vehicle from the point P as shown in FIG. During this time, since the vehicle position mark does not exist on the screen of the navigation device or does not move at the previous point P, the user can store the guidance route previously guided as in the conventional example shown in FIG. Suppose that you turn right at the intersection of Chozenji and left at the intersection of the gas station. Thereafter, when the vehicle travels to the point Q in (b), the main processor requests the coprocessor to transmit data of the current position, and the coprocessor outputs the data shown in FIG.

The main processor applies the data of the point Q as the current position or the route data to the map data, and as a result, the vehicle turns right at the intersection of Chozenji and left at the intersection of the gas station. It can be seen that the current location exists at the point Q in FIG. The main processor displays this point on the screen, uses the guidance route if it is stored, and calculates the guidance route to the fifth elementary school at the destination if it is not stored. indicate. The calculation at this time is also the same as that shown in FIG.
Since the vehicle does not travel to the point D as shown in the figure, there is less danger of occurrence of an inappropriate state such as passing through an intersection as in the related art. A route based on data as shown in FIG. 4B calculated by the coprocessor before the main processor starts up as described above may be displayed as reference information as shown by a broken line in FIG. 4C. it can.

In performing the vehicle position detection processing by the coprocessor in step S3 in the operation flow of FIG.
For example, it can be performed as shown in FIG. Note that the above processing in the coprocessor can be performed in various modes, but FIG. 3 solves the problem that an accurate signal is not output from the sensor particularly in the predetermined time after the start of power supply in the processing in the coprocessor. In addition, an operation example is shown focusing on processing for solving the problem that the calculation of the vehicle position by the GPS signal is slower than the calculation of the change of the vehicle position by the self-contained navigation sensor.

That is, at the time of the vehicle position detection processing by the coprocessor of FIG. 3, the time when the power supply is started when the accessory switch is first turned on is stored (step S31). Next, the current position calculation processing by the GPS receiver is started (step S32). In this operation, first, a GPS signal is fetched by a GPS receiver to receive a receivable satellite signal, and a receiving satellite selection process such as selecting four appropriate satellites having a good positional relationship among the satellites from among them is performed. A series of processes of analyzing data from these satellites and calculating the position of the receiver, that is, the vehicle position, is started. Since this process may take several seconds, in the illustrated example, it is immediately determined whether or not the vehicle has moved (step S33).

For example, as described in the above example, when the user temporarily stops at Seven-Eleven for shopping and starts running the engine within 1 to 2 seconds after starting the engine, the current position is not calculated by the GPS receiver. The vehicle will move to Therefore, in such a case, only the self-contained navigation sensor is operable, and the data of the self-contained navigation sensor is captured by the vehicle speed sensor and the angle sensor (step S34). Since there is no need to perform a special operation on these sensor signals, data on the current position can be obtained immediately. However, in particular, the angle sensor has a physical mechanism such as a cantilever formed by processing a semiconductor chip, is easily affected by the instability of the voltage, and is easily affected by the ambient temperature. Data that has not passed the predetermined time from the time is deleted (step S35). Here, when the predetermined time has not elapsed, the same operation can be performed even if the setting is made such that the data of the self-contained navigation sensor by the vehicle speed sensor and the angle sensor in step S34 is not performed.

The vehicle position is calculated based on the data of the self-contained navigation sensor after a predetermined time has passed since the power was supplied (step S36). Next, it is determined whether or not the current position can be calculated based on the GPS reception data (step S37). When it is determined in step S33 that the vehicle is not moving, the process directly proceeds to step S37, and similarly, it is determined whether or not the current position calculation process based on the GPS reception data has been performed.

As a result of this determination, if it is determined that the current position cannot be calculated based on the GPS reception data because, for example, only a short time has elapsed since the power was supplied, the process proceeds to step S39. The current position obtained only by the self-contained navigation obtained in S36 is output to the buffer. When it is determined in step S33 that the vehicle is not moving, it is not necessary to output new data of the current position to the buffer, but data indicating that the vehicle is not moving is output together with time data and recorded. It is also possible.

When it is determined in step S37 that the current position is calculated based on the GPS reception data, the current position based on the calculated GPS data is determined by the self-contained navigation sensor that has already been calculated in step S36. Corrected by the position data, the relative position from the starting point of the vehicle by the self-contained navigation sensor
The absolute position data based on the S data is output to the current position memory. If it is determined in step S33 that the vehicle has not moved yet and the vehicle reaches this point, the data from the self-contained navigation sensor is zero, and the current position based on the GPS data is directly output as the own vehicle position. .

G obtained in step S38
The current position obtained by correcting the current position based on the PS data with the current position data obtained by the self-contained navigation sensor, or step S3
The current position data obtained by only the self-contained navigation obtained in step 9 is stored in the vehicle position memory as the processing of step S4 in FIG. Thereafter, as described above, step S in FIG.
In 5 it is determined whether there is a vehicle position output request from the main processor, and if there is no output request, the process returns to step S3. However, in the operation flow of FIG. 3 showing step S3 in FIG. 2 in detail. To be precise, this part returns to step S33, and from the determination of whether or not the vehicle has moved again, the flow of FIG. 3 is repeated until the main processor starts up and a request for vehicle position output is issued.

In the above embodiment, an example is shown in which the present invention is applied to a navigation device mounted on a vehicle. However, for example, a portable information terminal which has become widespread in recent years, or a small portable computer such as a palmtop type is used for navigation. The present invention can be similarly used in a navigation device in which a program is installed and a current position is detected by connecting a GPS receiver.

FIG. 1 shows an example in which a coprocessor which calculates a current position by a predetermined program is used as a current position calculating means, based on a sensor signal which outputs a signal relating to the current position. The calculation may be performed using a dedicated circuit such as an ASIC that performs the above calculation by inputting the signal of the sensor.

[0049]

As described above, according to the present invention, the current position calculation which operates independently of the main processor and performs only the calculation of the vehicle position is performed without performing the calculation processing of the vehicle position by the main processor which performs a series of processes. Since it is performed by means, when traveling along the guidance route, the current position can be detected even if the power of the navigation device is temporarily turned off halfway and it restarts and moves immediately. , And this can be stored in the current location memory. Therefore, when the main processor is completely started up, it is possible to obtain accurate current position data by using the data of the current position memory, and to provide guidance of an erroneous guidance route based on erroneous current position data. Can prevent the confusion of the person.

Also, in the present invention, the present position detecting method and apparatus for performing the present position calculating means by a processing program using a calculation program or the circuit dedicated to the calculation. For the used one, the operation of the current position detection as described above can be performed by a program without using a special circuit, and for the one used for the calculation only, Thus, the operation can be performed more reliably.

The present invention further comprises a memory for storing a current position immediately before the power supply to the navigation device is cut off, wherein the current position when the navigation device is restarted is determined based on the current position stored in the memory. The navigation current position detecting device obtains the current position calculated by the current position calculating means when the navigation device is restarted, based on the current position immediately before the power supply to the navigation device is cut off. It is possible to determine the exact current position from the beginning at the start.

Further, the present position detecting device for navigation, wherein the present position calculating section according to the present invention deletes calculation data within a predetermined time from the start or does not perform the calculation for a predetermined time from the start, When a sensor that outputs data related to the current position outputs inappropriate data due to voltage fluctuations at the time of startup, etc., it prevents the detection of an erroneous current position by calculating the current position using this data. can do.

In the apparatus using the navigation current position detecting device according to the present invention for a vehicle, when the vehicle equipped with the navigation device is moving along a guidance route, the vehicle temporarily leaves the vehicle for shopping or the like. At times, it is necessary to stop the engine, remove the key of the car, and take out the car. In this case, the accessory switch that connects the power supply to the navigation device is forcibly cut off, and the navigation device frequently restarts. I do. In addition, it often moves a long distance after the restart before the main processor starts up, so that an accurate current position can be obtained when the main processor starts up, and the present invention can be effectively used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing main functional blocks of an embodiment in which the present invention is applied to a vehicular navigation device and their mutual relationship.

FIG. 2 is an operation flowchart of the embodiment.

FIG. 3 is an operation flow chart of a vehicle position detection processing portion performed by a coprocessor in the operation flow shown in FIG. 2 of the embodiment.

FIG. 4 is an explanatory view showing an operation example of the embodiment, and FIG.
FIG. 5B is a diagram illustrating a vehicle position and a guidance route immediately before the accessory switch is turned off, FIG. 6B is a diagram illustrating vehicle movement data from immediately after the accessory switch is turned on until the main processor starts, and FIG. It is a figure showing a vehicle position and a guidance route.

5A and 5B are explanatory diagrams showing a current position detection and a guidance route in a conventional navigation device, wherein FIG. 5A is a diagram showing a vehicle position and a guidance route immediately before an accessory switch is turned off, and FIG. FIG. 7C is a diagram illustrating an example of an incorrect vehicle position and a re-search guidance route, and FIG. 7C is a diagram illustrating an example of a vehicle position and a re-search guidance route corrected from the incorrect vehicle position.

[Explanation of symbols]

 Reference Signs List 1 main bus 2 EEPROM 3 main processor 4 ROM 5 RAM 6 image display processing unit 7 display 8 audio output unit 10 voice recognition processing unit 12 operation signal input unit 16 traffic information input unit 19 map / information data input unit 21 map drawing unit 22 Guidance route calculation unit 23 Guidance output unit 24 Accessory switch 25 Coprocessor 26 Vehicle position detection unit 27 GPS receiver 28 Self-contained navigation sensor 29 Distance sensor 30 Angle sensor 31 Vehicle position memory

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C032 HB02 HB05 HB22 HB31 HC16 HC22 HC23 HC24 HC31 HD03 HD07 HD16 HD21 2F029 AA02 AB07 AC02 AC08 AC14 AC16 AC20 AD07 5H180 AA01 FF04 FF05 FF07 FF22 FF25 FF27 FF27

Claims (7)

[Claims] 1. A current position detecting means for detecting a current position by a current position calculating means which operates separately from a main processor of a navigation device, and a current position of the vehicle detected by the current position calculating means is stored in a current position memory. A current position detecting method for navigation, comprising inputting current position data from the current position memory. 2. The navigation current position detection method according to claim 1, wherein the current position calculation means is performed by a coprocessor that performs processing by a calculation program or a circuit dedicated to the calculation. 3. A sensor for outputting a signal related to a current position, a current position calculating means for calculating a current position based on a signal from the sensor, and a current position memory for storing the calculated current position. The position calculation means operates separately from a main processor, and the main processor inputs current position data from the current position memory, wherein the current position detection device for navigation is provided. 4. The current position detecting device for navigation according to claim 3, wherein said current position calculating means is performed by a coprocessor which performs processing by a calculation program or a circuit dedicated to said calculation. 5. A memory for storing a current position immediately before the power supply to the navigation device is cut off, wherein a current position when the navigation device is restarted is determined based on the current position stored in the memory. 4. The current position detecting device for navigation according to claim 3, wherein: 6. The current position detection for navigation according to claim 3, wherein the current position calculation section deletes calculation data within a predetermined time from the start time or does not perform the calculation for a predetermined time from the start time. apparatus. 7. The navigation current position detection device according to claim 3, wherein the navigation current position detection device is used in a vehicle.