JP2006242901A - On-vehicle navigation device, navigation system, and navigation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To guide an optimum running route that reflects inherent characteristics by vehicles. <P>SOLUTION: An on-vehicle navigation device comprises detecting the road surface condition of a road, on which own vehicle is running on a vehicle control signal for controlling own vehicle during running, detecting the other road, on which the own vehicle may slide on the basis of the detected road surface condition, map basic information included on map data and outside information distributed from an information server, and recognizing it as a running impossible section. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an in-vehicle navigation device that guides a travel route of a vehicle while displaying a map on a display means inside the vehicle, a navigation system using the in-vehicle navigation device, and a navigation method.

  2. Description of the Related Art Conventionally, an in-vehicle navigation device that guides a travel route of a vehicle by display of a map, guidance by voice, or the like has been widely used. Further, in recent years, a technique for setting and guiding a route on which the host vehicle can safely travel is proposed instead of simply guiding a travel route set based on the length of time required (for example, Patent Documents). 1).

Specifically, this patent document 1 uses map data including a road network rank and a road situation rank obtained by ranking the road situation of a road on which a vehicle travels for each link according to a preset risk level. Thus, a technique for performing guidance by setting a relatively safe route as a travel route of the host vehicle is disclosed.
JP 2004-205348 A

  However, in the conventional vehicle-mounted navigation devices including the above-described Patent Document 1, guidance is provided by setting a travel route that is determined to be safe based on statistically processed information. Therefore, the characteristics unique to each vehicle were not reflected. For this reason, the conventional in-vehicle navigation device has a problem that it is not possible to guide the travel route according to the travel performance of each vehicle, and it is not always possible to provide the optimum travel route.

  The present invention was devised in view of the conventional situation as described above, and is an in-vehicle navigation device, a navigation system, and a navigation system capable of guiding an optimum travel route reflecting characteristics specific to each vehicle. It aims to provide a navigation method.

  In the present invention, in order to achieve the above object, the road surface condition of the road on which the host vehicle is traveling is detected based on a vehicle control signal for controlling the host vehicle that is traveling. Based on the detected road surface condition of the traveling road of the own vehicle and the basic map information included in the map data for displaying the map, other roads on which the own vehicle may slide are detected, The road is recognized as a travel avoidance section. The travel avoidance section recognized in this way can be recognized by the driver by, for example, displaying it on the display means so as to be identifiable on a map. In addition, by setting a route that avoids the travel avoidance section as the travel route of the host vehicle, it is possible to provide guidance on an optimal travel route that matches the travel performance of the host vehicle.

  According to the present invention, a road surface condition is detected from a vehicle control signal of a vehicle that is actually traveling, and another road on which the vehicle may slide is detected based on the detected road surface condition and basic map information. Since it is recognized as a travel avoidance section of the vehicle, it is possible to provide guidance on an optimal travel route that reflects the unique characteristics of each vehicle.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of the in-vehicle navigation device of the present embodiment. This in-vehicle navigation device is mounted on a vehicle and guides the travel route of the vehicle. As shown in FIG. 1, a control unit 11 that controls each unit in an integrated manner, and a display unit 12 that uses a liquid crystal display or the like. And an operation unit 13 having various operation switches, and a storage unit 14 for storing map data for displaying a map on the display unit 12. The in-vehicle navigation device draws a map using map data stored in the storage unit 14 based on a user operation via the operation unit 13 under the control of the control unit 11 and displays the display unit 12. The travel route of the vehicle (own vehicle) on which the in-vehicle navigation device is mounted is guided while being displayed on the screen. Here, the map data stored in the storage unit 14 includes inclination information indicating the inclination of the travel route, longitude / latitude / altitude information indicating the latitude and longitude, and the like as basic map information. The unit 11 can grasp the inclination, longitude and latitude, etc. of the travel route of the host vehicle from this map data.

  In particular, in the in-vehicle navigation device of the present embodiment, the control unit 11 has a function of detecting the road surface condition of the road on which the host vehicle is traveling based on a vehicle control signal for controlling the host vehicle that is traveling. Have. Specifically, the control unit 11 includes an ABS operation signal SABS from an ABS (Anti-Lock Brake System) system mounted on the host vehicle, a VDC operation signal SVDC from a VDC (Vehicle Dynamics Control) system, and Other vehicle control signals SOTH such as a signal indicating that the host vehicle is skidding are supplied. And the control part 11 detects that the slip generate | occur | produced in the said own vehicle based on these various vehicle control signals. The control unit 11 reads a vehicle speed pulse signal SSPD generated according to the vehicle speed, and detects the acceleration / deceleration of the host vehicle based on the vehicle speed pulse signal SSPD. Further, the control unit 11 calculates a road surface friction coefficient μ indicating the slipperiness of the road surface of the road on which the host vehicle is traveling based on the detected acceleration / deceleration of the host vehicle. And the control part 11 calculates the maximum inclination which can drive | work without the own vehicle slipping based on the calculated road surface friction coefficient (micro | micron | mu).

  Furthermore, the control part 11 can also collect external information from outside the host vehicle. That is, the in-vehicle navigation device of the present embodiment is composed of a radio beacon signal and an optical beacon signal distributed from an information server device installed in a VICS (Vehicle Information and Communication System) center (not shown), and FM (Frequency Modulation) multiplex broadcasting. The controller 11 has a function of acquiring the VICS information SVCS, and the control unit 11 collects seasonal information, weather forecast information, and the like of the planned travel route based on the acquired VICS information SVCS. Furthermore, the control unit 11 may collect the travel schedule area information and the like collected by a so-called probe car and distributed from a predetermined information server device by receiving the information via a communication device 15 such as a mobile phone. it can.

  Such an in-vehicle navigation device according to the present embodiment guides the travel route of the host vehicle under the control of the control unit 11 according to a series of procedures as shown in FIG.

  First, when it is detected in step S1 that slip has occurred in the host vehicle based on the vehicle control signal, the control unit 11 calculates the acceleration / deceleration of the host vehicle in step S2, and the calculated acceleration / deceleration in step S3. Based on the above, the road surface friction coefficient μ of the road on which the vehicle is traveling is calculated.

  Specifically, for example, when the control unit 11 detects that slip has occurred in the host vehicle by supplying the ABS operation signal SABS, for example, based on the increase or decrease in the number of pulses in the vehicle speed pulse signal SSPD obtained at that time. To calculate acceleration / deceleration. Then, the control unit 11 calculates the road surface friction coefficient μ = (acceleration / deceleration) / (gravity acceleration) using the calculated acceleration / deceleration and gravity acceleration. Further, when the control unit 11 detects that slip has occurred in the host vehicle by supplying the VDC operation signal SVDC, the controller 11 calculates the road surface friction coefficient μ by utilizing the vehicle speed pulse acceleration / deceleration. . Note that the control unit 11 may estimate the road surface friction coefficient μ based on various other vehicle control signals SOTH.

  Subsequently, in step S4, the control unit 11 stores the calculated road surface friction coefficient μ of the traveling road of the own vehicle in a storage unit such as an internal memory, and the own vehicle slides based on the road surface friction coefficient μ. The maximum degree of inclination that can be traveled is calculated. Further, in step S5, the control unit 11, for example, the basic map information stored in the storage unit 14 such as the road surface shape of the traveling road of the host vehicle, regional information, statistical information, season information, and weather forecast information, or external information. Based on the external information acquired from the information server device, the maximum inclination that the vehicle can travel without slipping is corrected for each road in another place. That is, the control unit 11 is based on the degree of slope of the road surface on the ease of slipping of each road in other places, but there is a difference in the slipperiness of the host vehicle even with the same slope according to the environmental conditions of the place. As a result, the maximum inclination with which the host vehicle can travel is corrected for each road based on various types of information that can specify the environmental conditions.

  Specifically, when it is determined that there is a possibility of slipping due to winter snow accumulation, freezing, or the like, estimation using the altitude as the road surface shape as an index is possible. Therefore, the control unit 11 determines that an area at a position higher than the altitude of the current location of the host vehicle is a section having a high possibility of sliding, and determines that there is a possibility of sliding even on a road having a small slope. That is, the control unit 11 considers a temperature drop per 100 m as 0.6 ° C., for example, and can travel on a road that is higher in elevation than the traveling road (current location) of the host vehicle without slipping the host vehicle. The maximum inclination is corrected to a small value according to the temperature drop.

  In addition, when it is determined that there is a possibility of slipping due to winter snow accumulation, freezing, or the like, estimation using latitude as an index as regional information is also possible. Therefore, the control unit 11 determines that there is a possibility of slipping even on a road with a low slope, with a region having a higher latitude than the current location of the host vehicle being a section having a high possibility of slipping. That is, the control unit 11 reduces the maximum inclination that the vehicle can travel without slipping using, for example, weather data, etc., for roads that are higher in latitude than the vehicle's travel road (current location). to correct.

  Furthermore, when it is determined that there is a possibility of slipping due to winter snow accumulation or freezing, estimation using weather data as statistical information as an index is also possible. Therefore, it is considered that the control unit 11 is likely to slip due to snow accumulation, freezing, or the like on a travel route that requires a long time only in winter based on past snow accumulation and temperature distribution. It is determined that there is a possibility of slipping even on a road with a small slope. That is, the control unit 11 corrects the maximum slope that the vehicle can travel without slipping to a small value on a road that is statistically considered to be snowy or frozen in winter. Note that the control unit 11 preferably stores the slip information in the period in the storage unit 14 or the like so that it can be reflected later.

  Furthermore, when it is determined that there is a possibility of slipping due to snow accumulation or freezing in winter and heavy rain, etc., estimation using weather as external information as an index is possible. Therefore, the control part 11 can be reflected in determination of the road with high possibility that the own vehicle slips by acquiring weather forecast information, such as temperature and the amount of snowfall according to the driving time zone of the own vehicle. That is, the control unit 11 determines that the host vehicle may slip if, for example, the forecast is that the temperature is below freezing or there is snow, and corrects the maximum inclination that the host vehicle can travel without slipping to a small value. To do. In addition, since it is predicted that mud is generated in the vicinity when heavy rain information is acquired even in the summer season, the control unit 11 does not detect the vehicle even when such information is acquired. The maximum inclination that can travel without slipping is corrected to a small value. In addition, the control unit 11 determines that the road on which the temperature is expected to rise sufficiently even in winter is not slippery, and corrects the maximum inclination that the vehicle can travel without slipping to a large value. You may make it do.

  When the control unit 11 corrects the maximum inclination that can be traveled on each road in other places based on the basic map information and the external information as described above, the control unit 11 displays the corrected value on the display unit 12 in step S6. For each road in the map, the slope of each road is calculated based on the basic map information, and a road having a slope greater than the maximum slope that the vehicle can travel without slipping is defined as a travel avoidance section. recognize. And the control part 11 displays the recognized driving avoidance area on the display part 12 as a state which can be identified on a map. For example, the control unit 11 clearly indicates that the road is a travel avoidance section, such as displaying a different color for the road set as the travel avoidance section displayed on the display unit 12.

  If the recognized travel avoidance section exists on the travel route set by the route search process, the control unit 11 searches for an alternative route that bypasses the travel avoidance section in step S7, and Start guidance. In addition, after starting the guidance of an alternative travel route, the control part 11 may be made to show a predetermined warning message and a warning sound, when driving | running | working the area which cannot drive | work still. In addition, when a new route search is performed, the control unit 11 may search for a travel route that avoids the recognized travel avoidance section and start guidance for the travel route.

  As described above, the in-vehicle navigation device according to the present embodiment is a road on which the host vehicle may slide based on various information such as a vehicle control signal, basic map information, and external information under the control of the control unit 11. This is detected and recognized as a travel avoidance section, and this travel avoidance section is displayed on the display unit 12 so as to be identifiable on a map, and at the time of route search, a route that avoids this travel avoidance section is searched and guided, When a travel avoidance section is detected during route guidance, guidance is performed by rerouting the detour route. Therefore, in the in-vehicle navigation device of the present embodiment, as an example of slipping due to seasonal factors, if a route in a mountainous area that is appropriate in the summer is selected in winter, it can be boiled early before entering the mountainous area. It is possible to determine the possibility of slipping and select an alternative travel route. In addition, in the in-vehicle navigation device of the present embodiment, as an example of slipping due to weather factors, the scheduled traveling time is early in the morning and the temperature is below freezing even in a section where the vehicle can currently travel without slipping. For areas where there is a forecast for the weather, slipping accidents during freezing can be prevented by selecting a flat route with little difference in elevation. Furthermore, in the in-vehicle navigation device of the present embodiment, as an example of slipping due to the situation of the own vehicle, the traffic information is not closed, but the tire of the own vehicle is worn down, and traveling on snowy roads and frozen roads is not possible. If it is expected to be difficult, the alternative route guidance can be started when the vehicle starts to slip by reflecting the traveling performance of the host vehicle, and an unreasonable travel plan can be prevented. Furthermore, it is assumed that a chain is used on a snowy road in winter, but the chain cannot be used on a dry road, so it is difficult to grasp the timing of desorption of the chain. In such a case, in the in-vehicle navigation device of the present embodiment, by displaying the section where the slip is expected on the display unit 12, it is possible to determine the desorption timing of the chain before reaching the section. It can contribute to securing a safe place.

  As described above in detail, in the vehicle-mounted navigation device of the present embodiment, the host vehicle travels based on the vehicle control signal for controlling the host vehicle that is traveling under the control of the control unit 11. The road surface where the vehicle is likely to slip is detected based on the detected road surface state, the basic map information included in the map data, and external information distributed from the information server device outside the vehicle. It is detected and recognized as a travel avoidance section, and this travel avoidance section is displayed on the display unit 12 so that it can be identified on a map, or a route that avoids this travel avoidance section is searched for route guidance. Therefore, it is possible to provide optimum guidance according to the running performance of the host vehicle.

  Further, in this in-vehicle navigation device, by calculating the road surface friction coefficient μ of the traveling road surface, it is possible to obtain a road where the actual vehicle slip is likely to occur as the traveling avoidance section according to the inclination of the road. . Specifically, in this in-vehicle navigation device, under the control of the control unit 11, the maximum inclination that the vehicle can travel without slipping is calculated based on the detected road surface condition, and the calculated maximum travelable By obtaining a road having an inclination greater than the inclination as the travel avoidance section, it is possible to recognize a road having a high possibility that the own vehicle will actually slip as the travel avoidance section.

  The on-vehicle navigation device described above is an application example of the present invention, and the present invention is not limited to the above-described example. Specific hardware is used as long as it does not depart from the technical idea of the present invention. Of course, various changes in the hardware configuration and the like are possible.

It is a block diagram which shows schematic structure of the vehicle-mounted navigation apparatus to which this invention is applied. It is a flowchart which shows a series of procedures at the time of performing a driving | running route guidance in the vehicle-mounted navigation apparatus to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Control part 12 Display part 13 Operation part 14 Memory | storage part 15 Communication equipment SABS ABS operation signal SVDC VDC operation signal SOTH Vehicle control signal SSPD Vehicle speed pulse signal SVCS VICS information

Claims (9)

In an in-vehicle navigation device that guides the travel route of a vehicle while displaying a map on a display means inside the vehicle,
Road surface condition detecting means for detecting the road surface condition of the road on which the host vehicle is traveling based on a vehicle control signal for controlling the host vehicle that is traveling;
Other roads on which the host vehicle may slip based on the road surface condition of the traveling road of the host vehicle detected by the road surface condition detecting means and the basic map information included in the map data for displaying the map And a travel avoidance section recognizing means for recognizing the road as a travel avoidance section. The in-vehicle navigation device according to claim 1, wherein the road surface condition detecting means calculates a road surface friction coefficient of a traveling road of the host vehicle. Based on a road surface friction coefficient of the traveling road of the host vehicle detected by the road surface condition detecting unit, and an inclination degree calculating unit that calculates a maximum inclination degree that the host vehicle can travel without slipping,
The in-vehicle navigation device according to claim 2, wherein the travel avoidance section recognizing unit recognizes a road having an inclination larger than the maximum inclination calculated by the inclination calculation unit as the travel avoidance section. The travel avoidance section recognition means collects the road surface condition of the traveling road of the own vehicle detected by the road surface condition detection means, the basic map information included in the map data for displaying the map, and the outside of the own vehicle. The in-vehicle navigation device according to claim 1, wherein another road on which the host vehicle is likely to slide is detected based on the external information. The in-vehicle navigation device according to claim 1, further comprising display control means for displaying the travel avoidance section recognized by the travel avoidance section recognition means on the display means so as to be identifiable on a map. The vehicle-mounted navigation device according to claim 1, further comprising route search means for searching for a route that avoids the travel avoidance section recognized by the travel avoidance section recognition means as a recommended travel route of the host vehicle. The route search means, when the host vehicle is running on the recommended travel route, if a new travel avoidance section is recognized on the recommended travel route by the travel avoidance section recognition means, The in-vehicle navigation device according to claim 6, wherein a new route that bypasses the section is searched again. A vehicle-mounted navigation device mounted on the vehicle; and an information server device that distributes predetermined information to the vehicle mounted with the vehicle-mounted navigation device, wherein the vehicle-mounted navigation device displays a map on display means inside the vehicle. In the navigation system that guides the driving route of the vehicle,
The in-vehicle navigation device detects a road surface condition of a road on which the host vehicle is traveling based on a vehicle control signal for controlling the host vehicle that is traveling, and the detected road surface condition of the traveling road of the host vehicle, Based on the basic map information included in the map data for displaying the map and the information distributed from the information server device, another road on which the host vehicle is likely to slide is detected, and the road travels. A navigation system characterized by being recognized as an avoidance section. In a navigation method for guiding a travel route of a vehicle while displaying a map on a display means inside the vehicle,
Detecting a road surface condition of a road on which the host vehicle is traveling based on a vehicle control signal for controlling the host vehicle that is traveling;
Based on the detected road surface condition, basic map information included in the map data for displaying the map, and external information collected from the outside of the own vehicle, other roads on which the own vehicle may slide are detected. And a step of recognizing the road as a travel avoidance section.

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