Device and system for preventing traffic congestion

The present invention relates to a device and a system for preventing the occurrence of traffic congestion on a road.

Traffic congestion is detrimental to many people, so its improvement is very meaningful, but the essential improvement requires measures at the infrastructure level, such as adding roads, and should be dealt with easily. Can't. As a conventional technique that contributes to alleviation of traffic congestion, for example, there is one disclosed in Patent Document 1. This technology simulates traffic flow, predicts traffic congestion, and supports recommended driving to realize smooth traffic. However, in the technique disclosed in Patent Document 1, it is necessary to perform a large-scale arithmetic processing in order to simulate a traffic flow. In addition, in order to perform simulations that are more adapted to actual traffic conditions, it is premised that the infrastructure has been developed to some extent, such as installing an N system at a point in front of where traffic congestion is likely to occur.

Further, in Patent Document 2, the points where the occurrence of traffic congestion is predicted are registered in advance on the map data, and the driver is notified so as not to reduce the speed of the vehicle when the traveling vehicle approaches the above points. A configuration is disclosed in which a warning is given in advance.

<p><patcit num="1"><text>Japanese Patent Application Laid-Open No. 2008-282275</text></patcit><patcit num="2"><text>Japanese Patent Application Laid-Open No. 2005-300184</text></patcit></p>

<p> In the technique disclosed in Patent Document 2, the driver is warned only on the condition that the vehicle approaches the predicted point of occurrence of traffic congestion. However, since the actual traffic conditions change from moment to moment, it is assumed that warnings may be issued uniformly even though the warnings should not be necessary. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a traffic congestion prevention device and a traffic congestion prevention system capable of alleviating traffic congestion without giving unnecessary warnings by a simpler configuration. is there.</p>

<p> According to the traffic jam prevention device according to claim 1, the control means measures the current position of the vehicle with respect to a point or road section where the traffic jam is predicted to occur on the map data (hereinafter referred to as a traffic jam prediction point or the like). When the vehicle reaches a position within a predetermined distance, traffic information is acquired from the outside such as a traffic information center via a traffic information acquisition means, and if there is no congestion at the above point or road section, the vehicle Notifies the occupants of the vehicle with a message prompting them to maintain the traveling speed of the vehicle. That is, since the message is notified only when it is certain that the traffic jam has not yet occurred based on the traffic information acquired from the outside at the traffic jam occurrence prediction point or the like, it is possible to appropriately notify the occupants of the vehicle. ..</p><p> According to the congestion prevention device according to claim 2, the control means notifies a message when the traveling speed of the vehicle tends to decrease, so that appropriate notification can be performed when there is a higher need. ..</p><p> According to the congestion prevention device according to claim 3, when the preceding vehicle does not exist in the predetermined area on the front side of the own vehicle, the control means notifies and controls a message for maintaining the traveling speed of the own vehicle. A control command for maintaining the current traveling speed of the own vehicle is output via the command output means. Therefore, even if the driver does not actively perform a driving operation for maintaining the traveling speed, the traveling speed is automatically maintained after the safety in front of the own vehicle is confirmed.</p><p> According to the traffic jam prevention device according to claim 4, the control means prompts the occupants of the vehicle to reduce the traveling speed when the information that the traffic jam is occurring at the predicted traffic jam occurrence point or the like is obtained. Is notified. Therefore, when traffic congestion actually occurs, it is possible to prevent the driver from further extending the traffic congestion by causing the driver to reduce the traveling speed in advance.</p><p> According to the congestion prevention device according to claim 5, the control means notifies a message of reducing the traveling speed of the own vehicle when the preceding vehicle does not exist in the predetermined area on the front side of the own vehicle. , A control command for reducing the traveling speed is output to the own vehicle via the control command output means. Therefore, even when traffic jams actually occur, the traveling speed is automatically reduced after the safety in front of the own vehicle is confirmed, even if the driver does not actively perform the driving operation, as in claim 3. Can be made to.</p><p> According to the traffic jam prevention device according to claim 6, the vehicle speed maintenance vehicle notification means notifies the following vehicle that the own vehicle will be a vehicle that maintains the traveling speed for avoiding the occurrence of traffic jam. Therefore, if the driver of the following vehicle maintains the same traveling speed as the vehicle in front based on the above notification, it is possible to prevent the extension of the traffic jam.</p><p> According to the traffic jam prevention device according to claim 7, the information such as the predicted traffic jam occurrence point stored in the map data storage means is acquired and updated by communicating with the outside, so that the road condition changes. Even if the predicted location of traffic congestion disappears or a new traffic jam occurs, the information of the map data storage means can be maintained in the latest state.</p><p> According to the traffic jam prevention system according to claim 8, when the current position of the vehicle reaches a position within a predetermined distance with respect to the predicted traffic jam occurrence point or the like, the control means of the in-vehicle device and the ID information of the own vehicle are used. , Current position information and speed information are transmitted to the traffic information center. When the traffic information center receives each of the above information, if there is no traffic jam at a traffic jam prediction point or the like where the vehicle is approaching, and the traveling speed of the vehicle is equal to or less than a predetermined speed, Message information for urging the in-vehicle device to maintain or increase the traveling speed is transmitted. Then, the control means of the in-vehicle device receives the message information and notifies the message information.</p><p> That is, the traffic information center can collect road traffic information in a predetermined area to grasp the presence or absence of traffic congestion in each place, and can also obtain information on vehicles traveling in the area via the on-board unit. .. Therefore, it is possible to determine whether or not traffic congestion actually occurs at the traffic congestion prediction point, etc., and objectively determine what kind of information should be given to the vehicle approaching the traffic congestion occurrence prediction point, etc. It is possible. Then, the occupant of the vehicle receives a message from the traffic information center via the in-vehicle device to know how to drive when the vehicle is approaching a traffic jam prediction point or the like. Since it can be recognized, it is possible to prevent the occurrence of traffic congestion by preventing the decrease in traveling speed when the traffic congestion has not yet occurred.</p><p> According to the traffic jam prevention system according to claim 9, in the traffic information center, when the traffic jam is occurring at a traffic jam prediction point or the like where the vehicle is approaching, and the traveling speed of the vehicle is a predetermined speed. If it exceeds, message information for urging the in-vehicle device of the vehicle to reduce the traveling speed is transmitted, and when the control means of the in-vehicle device receives the message information, the content of the message is notified. To do. Therefore, when a traffic jam actually occurs, the driver can prepare for the traffic jam by reducing the traveling speed.</p><p> According to the traffic jam prevention system according to claim 10, when the traffic information center sends message information for urging the in-vehicle device to reduce the traveling speed, the traffic information center is selected from the vehicle located at the end of the traffic jam line. Comparing the received speed information with the running speed of the vehicle to which the message information is transmitted, and calculating an appropriate running speed to alleviate the traffic jam or prevent further extension of the traffic jam, the speed information is also included. Send. Then, the control means of the in-vehicle device notifies the traveling speed to be set together with the content of the received message. Therefore, the occupants of the vehicle can set and drive an appropriate speed in order to alleviate the traffic congestion.</p><p> According to the traffic jam prevention system according to claim 11, when the control means of the in-vehicle device requests the traffic information center to transmit information such as the predicted traffic jam occurrence point, the traffic information center is held by itself at that time. Information such as the predicted location of traffic congestion is transmitted to the in-vehicle device. Then, when the on-board unit control means receives the transmitted information, it updates the information such as the traffic jam occurrence prediction point in the map data storage means. Therefore, even if the predicted location of traffic congestion disappears due to a change in road conditions or the like, or when a new traffic jam occurs, the information of the map data storage means on the vehicle-mounted device side can be maintained in the latest state.</p>

<figref num="1">This is the first embodiment, and is a functional block diagram showing the overall configuration of the congestion prevention system.</figref><figref num="2">Flowchart showing the processing contents performed by the control device</figref><figref num="3">Diagram showing an example of point A</figref><figref num="4">The figure which shows an example of the navigation screen displayed on the display device.</figref><figref num="5">A diagram showing an example of a road section where congestion is predicted, which is the second embodiment.</figref><figref num="6">Figure 2 equivalent figure</figref><figref num="7">Fig. 3 equivalent diagram showing the third embodiment</figref><figref num="8">Figure 2 equivalent figure</figref><figref num="9">Figure 4 equivalent</figref><figref num="10">This is the fourth embodiment, and is a flowchart showing the processing contents of each of the navigation device and the information center.</figref><figref num="11">FIG. 8 equivalent diagram showing the fifth embodiment</figref><figref num="12">Fig. 1 equivalent diagram showing the sixth embodiment</figref><figref num="13">Figure 2 equivalent figure</figref><figref num="14">FIG. 10 equivalent diagram showing the 7th embodiment</figref>

(First Example) Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is a schematic functional block diagram showing the overall configuration of the traffic congestion prevention system 1. The traffic jam prediction system 1 includes an information center 2 and a vehicle navigation device (traffic jam prevention device, in-vehicle device) 3. The vehicle navigation device 3 includes a position detector (current position acquisition means) 4, a map data input unit (map data storage means) 8, an operation switch group 9, a control device (control means, notification means) 10, and an external memory 11. Display device (notification means) 12, transmitter / receiver (traffic information acquisition means) 13, voice controller (notification means) 14, speaker (notification means) 15, voice recognition device 16, microphone 17, remote control sensor 18, remote control terminal (hereinafter) It is equipped with 19 (called a remote controller) and 20 data communication means (traffic information acquisition means) 20.

The control device 10 is composed of a microcomputer, and internally includes a CPU, ROM, RAM, I / O, and a bus line (none of which is shown) connecting these configurations. The control device 10 is input from the position detector 4, the map data input unit 8, the operation switch group 9, the external memory 11, the display device 12, the transmitter / receiver 13, the voice controller 14, the speaker 15, the voice recognition device 16, and the remote control sensor 18. Predetermined processing (for example, map scale change processing, menu display selection processing, destination setting processing, route search execution processing, route guidance start processing, current position correction processing, display screen change processing, volume adjustment) based on various information provided. Processing, notification control processing, etc.) is executed. Further, the control device 10 gives a user instruction using the operation switch group 9 and gives an instruction to the data communication means 20 at regular time intervals to perform phase-direction communication.

The position detector 4 is a gyroscope 5, a distance sensor 6, and a GPS receiver 7 for GPS (Global Positioning System) that detects the current position of the vehicle based on radio waves from satellites, and a vehicle speed sensor (speed detection means). Has 30 Since each of these sensors 5, 6, 7, and 30 has errors having different properties, they are configured to be used while being complemented by a plurality of sensors. Depending on the accuracy, a part of the above may be used, or a steering rotation angle sensor, a wheel speed sensor arranged on each driving wheel, or the like may be used.

The map data input unit 8 is equipped with a storage medium (not shown) and stores various data including so-called map matching data, map data, and marker data for improving the accuracy of position detection stored in the storage medium. It is a device for inputting. The storage medium is, for example, a CD-ROM, a DVD-ROM, an HDD (hard disk drive), a memory card, or the like. The control device 10 can determine the road type of the traveling road of the own vehicle from the position of the own vehicle detected by the position detector 4 and the map data. Further, in the above map data, points where the occurrence of traffic congestion is predicted (referred to as points where traffic congestion occurs and points A) are stored in advance.

The operation switch group 9 uses, for example, a touch switch or a mechanical switch integrated with the display device 12, and various functions (for example, map scale change, menu display selection, destination setting, etc.) are used in the control device 10 by operating the switch. Gives operation instructions for route search, route guidance start, current position correction, display screen change, volume adjustment, etc.). Further, the remote controller 19 is provided with a plurality of operation switches, and by operating the switches, various command signals are input to the control device 10 via the remote controller sensor 18 to cause the control device 10 to execute various functions. The operation switch group 9 and the remote controller 19 can cause the control device 10 to execute the same function by any switch operation.

When the destination is set from the remote control sensor 18 via the remote controller 19 or by the operation switch group 9, the control device 10 automatically determines the optimum route from the current position detected by the position detector 4 to the destination. Search for and set and display the guidance route. As a method for automatically setting the optimum route, a method such as Dijkstra's algorithm is known. The set route is superimposed and displayed together with the current position mark detected by the position detector 4 on the display map displayed on the display device 12 based on the information of the map data input unit 8. In addition to the current position and route, other information such as the current time, traffic jam information, and alert information can be additionally displayed on the display map.

The external memory 11 is a writable large-capacity storage device such as an HDD. The external memory 11 has a purpose of storing a large amount of data or data to be retained even when the power is turned off, copying frequently used data from the map data input unit 8 and using the data. The external memory 11 may be a removable memory (flash memory or the like) having a relatively small storage capacity.

The display device 12 notifies by displaying a map, a destination selection screen, guidance items of warning information, etc. as navigation, and can display in full color. For example, a liquid crystal display device, an organic EL display device, or the like is used. It is composed of. The transmitter / receiver 13 is a device that receives traffic information or the like provided from the outside, for example, VICS (registered trademark) center 31, or the like, and also transmits vehicle information, user information, or the like to the outside. The information received from the outside is processed by the control device 10. Further, if necessary, the information processed by the control device 10 can be transmitted from the transmitter / receiver 13.

The speaker 15 notifies the outside of a predetermined voice (voice for guidance, explanation of screen operation, voice recognition result, guidance item of attention information, etc.) based on the voice output signal input from the voice controller 14. The microphone 17 inputs the voice uttered by the operator as an electric signal to the voice recognition device 16. The voice recognition device 16 collates the input voice of the operator uttered through the microphone 17 with the vocabulary data (comparison target pattern) in the recognition dictionary (not shown) stored internally, and has the highest degree of matching. The thing is input to the voice controller 14 as a recognition result. The voice controller 14 controls the voice recognition device 16 and controls the talkback output (voice output) through the speaker 15 to the operator who has received the voice input. In addition, the process of inputting the recognition result of the voice recognition device 16 to the control device 10 is also performed.

The control device 10 executes a predetermined process (for example, a process corresponding to the various functions described above) for the utterance of the operator based on the information from the voice recognition device 16. Further, the route guidance voice information and the like processed by the control device 10 are appropriately notified from the speaker 15 via the voice controller 14.

The data communication means 20 has a data-based phase-direction communication function, and is composed of, for example, a mobile phone, a car phone, or the like, and is connected to the control device 10. Further, when the data communication means 20 receives the request from the information center 2, mutual communication becomes possible. Further, the control device 10 obtains information from the information center 2 by requesting information requests (text information, weather information, other vehicle information, facility information, advertisement information, etc.) via the data communication means 20. The information center 2 is a line terminal device 23 that communicates via the telephone office 22, and a server that processes necessary information such as text information, music information, traffic information, weather information, other vehicle information, facility information, and advertisement information as contents. It is equipped with 24 and a database 25 that stores necessary data such as each of these information as contents, and is connected to the radio base station 21 through the telephone station 22 between the radio base station 21 and the vehicle navigation device 3. Send and receive data with.

The vehicle navigation device 3 described above can acquire vehicle information such as sensor signals from various sensors of the own vehicle (probe car) and operation status information of each part, and these vehicle information and the position information of the own vehicle can be obtained. It is designed to be sent to the information center 2 as probe information. When a destination is set, the destination information is transmitted to the information center 2. The information center 2 processes the probe information obtained by communication by the server 24, and stores various travel-related information in the database 25. The travel-related information includes facility information, warning information (road surface information, weather information, traffic jam information, etc.) and the like. Then, when the guidance information request is transmitted from the vehicle, the information center 2 searches the database 25 for the necessary alert information by the server 24, and transmits the data using the line terminal device 23.

Next, the operation of this embodiment will be described with reference to FIGS. 2 to 4. FIG. 2 is a flowchart showing the processing contents performed by the control device 10. It should be noted that this process is repeatedly executed, for example, in a cycle of about 1 minute. The control device 10 determines whether or not the current position of the own vehicle is within a predetermined distance (for example, several km to several hundred m) with respect to the nearest point A located in the traveling direction on the map data (for example, several km to several hundred m). Step S1).

Here, FIG. 3 shows an example of point A. In this way, when the slope is uphill to some extent and the slope continues for a relatively long distance, the speed of the vehicle naturally decreases while traveling uphill without the driver being aware of it. It often ends up. Then, when the speed of the vehicle in front decreases, the speed of the following vehicle also decreases in a chain reaction, so that it becomes the point A where the occurrence of traffic congestion is predicted. In addition, as point A, for example, the entrance of a tunnel or a point where the number of lanes decreases on the road is assumed.

When the own vehicle approaches the above point A (for example, the point where the uphill slope starts) within a predetermined distance (step S1: YES), the control device 10 is set to the VICS center 31 (or information center 2). Receives traffic information, etc. provided by, and determines whether or not there is congestion around point A in front of the vehicle (step S2). If it is determined from the traffic information acquired in step S2 that there is no congestion around point A (YES), the control device 10 uses the vehicle speed sensor 30 to determine that the traveling speed of the own vehicle is appropriate for avoiding congestion. Determine if the speed is lower than the normal speed (step S3). Here, the "appropriate speed for avoiding traffic congestion" is, for example, a speed that exceeds 80% of the speed limit set on the road on which the vehicle is traveling.

When it is determined in step S3 that the traveling speed is decreasing (YES), the control device 10 alerts the driver not to decrease the traveling speed by outputting a voice message from the speaker 15, for example. .. For example, output a message such as "This is the point where natural traffic jams will occur. Please drive while paying attention to the slowdown" (step S4). FIG. 4 is an example of the navigation screen displayed on the display device 12 in this case (however, the state immediately after the vehicle has passed the point A is shown). Further, as shown in FIG. 4, a character message may be displayed on the screen of the display device 12 at the same time.

As described above, according to the present embodiment, the control device 10 of the navigation device 3 has the current position of the own vehicle within a predetermined distance from the congestion occurrence prediction point set on the map data; the point A. When it reaches the position, it acquires traffic information from VICS Center 31 and so on. Then, when there is no traffic jam at point A, a message prompting the occupants of the vehicle to maintain the running speed (or increase the speed may be used) is notified. Therefore, at the point A, the message is notified only when it is certain that the traffic jam has not yet occurred based on the traffic information acquired from the outside, so that the occupant of the vehicle can give an appropriate notification. Further, since the control device 10 notifies a message when the traveling speed of the vehicle tends to decrease, it is possible to perform an appropriate notification when the necessity is higher.

(Second Example) 5 and 6 show the second embodiment, the same parts as those in the first embodiment are designated by the same reference numerals, description thereof will be omitted, and different parts will be described below. The second embodiment shows the processing when the road section where the occurrence of traffic congestion is predicted (between the point S and the point E) is set instead of the point A on the map.

First, in step S5, the S point, which is the starting point of the traffic congestion prediction interval, is determined by a predetermined distance (whether or not it has approached within the predetermined distance, and if it is within the predetermined distance (YES, in this case, the S point is passed). (Including the case where it has already been completed), it is determined whether or not the vehicle has passed (passed) the E point, which is the end point of the congestion prediction interval (step S6). If the E point has not been passed (YES), Receives traffic information, etc. from the VICS center 31, etc., and determines whether or not there is congestion in the traffic jam prediction interval in front of the own vehicle, and whether or not there is congestion around point E (step). S7). Then, if there is no congestion (YES), steps S3 and S4 are executed in the same manner as in the first embodiment. As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained for the congestion occurrence prediction section set on the map data.

(Third Example) 7 to 9 show the third embodiment, and the parts different from the first embodiment will be described. In the third embodiment, as shown in FIG. 7, when a traffic jam has already occurred at the point A of the first embodiment, a message prompting the occupants of the vehicle heading for the point A to decelerate is given. , To alleviate / eliminate traffic congestion, or to prevent further extension of traffic congestion. That is, usually, there are many vehicles that suddenly reduce the speed when approaching the point A where the traffic jam is occurring, which may cause the extension of the traffic jam to be promoted.

In the flowchart shown in FIG. 8, first, it is determined whether or not the own vehicle is in front of the point A (step S11). In this case, the "front" is preferably set to a distance equal to or greater than the "predetermined distance" in step S1 of the first embodiment. If you are in front of point A (YES), you will also receive traffic information etc. from VICS center 31 etc. and judge whether there is a traffic jam in front of your vehicle to point A ( Step S12).

In step S12, if there is a traffic jam up to point A (YES), it is determined whether the distance from the own vehicle to the end of the congested convoy is less than or equal to the specified value (for example, about several kilometers). (Step S13) If it is less than or equal to the specified value (YES), the speed information of the own vehicle is acquired. Then, the predicted time until reaching the end of the congested convoy at the current traveling speed is obtained, and it is determined whether or not the predicted time is equal to or less than the specified value (for example, about several minutes) (step S14).

In step S14, if the predicted time is less than or equal to the specified value (YES), as in the first embodiment, for example, by outputting a voice message from the speaker 15, the traveling speed is reduced for the driver. Call attention (step S15). For example, a message such as "Natural traffic jams are occurring in the future. If you reduce the speed to 50km / k, you can alleviate the traffic jams." FIG. 9 is an example of a navigation screen displayed on the display device 12 in this case.

As described above, according to the third embodiment, when the information that the traffic jam has already occurred at the point A is obtained, the control device 10 sends a message to the occupants of the own vehicle to urge the occupants of the own vehicle to reduce the traveling speed. Since the notification is provided, when a traffic jam actually occurs, the driver can be made to reduce the traveling speed in advance to alleviate the traffic jam at the point A, or prevent the traffic jam from further extending.

Further, in this case, as shown by the broken line in FIG. 1, when the navigation device 3 is provided with the pace car display (vehicle speed maintenance vehicle notification means) 50, the display 50 may be displayed according to the driver's selection. good. That is, the pace car indicator 50 is arranged at the rear of the vehicle to indicate to the following vehicle that the vehicle is a vehicle traveling at a speed for preventing the occurrence of traffic congestion. For example, a display such as blinking a text message such as "driving at a traffic jam prevention pace" is displayed. With such a configuration, the driver of the following vehicle can prevent the occurrence of traffic congestion by maintaining the same traveling speed as the vehicle in front based on the above notification.

(Fourth Example) FIG. 10 shows a fourth embodiment of the present invention, and a part different from the first embodiment will be described. The fourth embodiment shows a case where the navigation device 3 communicates with the information center 2 and performs the same processing contents as those of the first embodiment while transmitting and receiving information. FIG. 10 shows the processing contents of the navigation device 3 and the information center 2. When the navigation device 3 (referred to as the in-vehicle device X) approaches point A in the same manner as in step S1 (step S21: YES), the information center 2 provides the ID information set for itself, the current position and speed information of the own vehicle, and the information center 2. Send to (step S22). That is, the vehicle also functions as a probe car in this case.

The information center 2 side receives various information similarly transmitted from other in-vehicle devices (navigation devices) and traffic information provided by the VICS center 31 (step S31). Then, while generating congestion information for all points A existing in the area managed by the vehicle, grasping the position and traveling speed information received from the in-vehicle device of each vehicle, and updating the database 25 as needed. Is being built (step S32).

When the information center 2 receives the information from the in-vehicle device X transmitted in step S22 (step S33), the information center 2 determines whether or not the in-vehicle device X should increase the traveling speed under the current traffic conditions. Determine (step S34). That is, here, the information center 2 makes a judgment in steps S2 and S3 in the first embodiment by using the information in step S32. Then, when it is determined that it is better to increase the traveling speed (YES), information indicating that fact is transmitted to the in-vehicle device X to notify the vehicle (step S35). Then return to step S31.

On the other hand, on the in-vehicle device X side, it is determined in step S23 whether or not there is a notification from the information center 2 that the traveling speed should be increased, and if there is a notification, a voice message is given in the same manner as in (YES) step S4. Is output (step S24). Further, in step S23, if there is no notification from the information center 2 (NO), it is determined whether or not the vehicle has passed point A (step S25), and if it has not passed (NO), the process returns to step S22 and passes. If so (YES), the process ends.

As described above, according to the fourth embodiment, when the own vehicle approaches the point A, the control device 10 of the navigation device 3 transfers the ID information of the own vehicle, the current position information, and the speed information to the information center 2. Send. When the information center 2 receives each information, if there is no traffic jam at the point A where the vehicle is approaching and the traveling speed of the vehicle is equal to or less than a predetermined speed, the information center 2 informs the navigation device 3. On the other hand, message information for promoting the maintenance or increase of the running speed is transmitted. Then, the control device 10 receives the message information and notifies the message information.

That is, the information center 2 can collect road traffic information in a predetermined area to grasp the presence or absence of traffic congestion in each area, and can also obtain information on each vehicle traveling in the area via the on-board unit. Therefore, it is possible to judge whether or not there is actually a traffic jam at the point A, and it is possible to objectively judge what kind of information should be given to the vehicle approaching the point A. Then, the occupant of the vehicle can recognize how to drive when the own vehicle is approaching the point A by receiving the message from the information center 2 via the navigation device 3. Therefore, if there is no traffic jam yet, the running speed can be maintained to prevent the occurrence of traffic jam.

(Fifth Example) FIG. 11 shows a fifth embodiment of the present invention, and a part different from the third and fourth embodiments will be described. In the fifth embodiment, as in the third embodiment, when there is a traffic jam up to the point A, a process of outputting a message to reduce the traveling speed in order to prevent further traffic jams is performed. , The case where it is performed on the information center 2 side as in the fourth embodiment is shown. FIG. 11 is a diagram corresponding to FIG. 8 of the third embodiment, and determines the process corresponding to step S34 of the fourth embodiment (however, in the fifth embodiment, is it better to reduce the traveling speed? ) Part is shown in detail.

The information center 2 performs the same processing as steps S11 to S14 in FIG. 8 in steps S41 to S44, and if it determines (YES) in step S44, the speed of the vehicle of the on-board unit X and the end of the congested convoy. Calculate how much deceleration should be done from the running speed of the vehicle located in (step S45). Then, as in step S35, information on the recommended traveling speed is transmitted to the vehicle-mounted device X (step S46). Then, the vehicle-mounted device X outputs the recommended traveling speed transmitted from the information center 2 by a voice message in the process corresponding to steps S22 and S23.

As described above, according to the fifth embodiment, when the information center 2 transmits the message information for urging the in-vehicle device X to reduce the traveling speed, the information center 2 is selected from the vehicle located at the end of the congested vehicle line. When the received speed information is compared with the traveling speed of the vehicle of the vehicle-mounted device X to calculate an appropriate traveling speed in order to alleviate the traffic congestion, the speed information is also transmitted. Then, the control device 10 of the vehicle-mounted device X notifies the traveling speed to be set together with the content of the received message, so that the occupant of the vehicle can set an appropriate speed and drive in order to alleviate the traffic congestion. ..

(6th Example) 12 and 13 show the sixth embodiment, and the parts different from the first embodiment will be described. The navigation device 32 of the sixth embodiment includes an in-vehicle communication interface (I / F) 33, and can communicate with the vehicle control device (vehicle control means) 34 by a communication protocol such as an in-vehicle LAN (Local Area Network). It has become. The vehicle control device 34 is composed of a microcomputer or an ECU (Electronic Control Unit), and can control the operation of the vehicle. Then, the control device (control command output means) 10 outputs a command for driving and controlling the own vehicle to the vehicle control device 34.

In addition, the navigation device 32 includes a preceding vehicle detection sensor (preceding vehicle detecting means) 35 composed of, for example, an ultrasonic sensor and a laser sensor, and is ahead within a distance of several tens of meters to 100 m in front of the own vehicle. It is possible to detect whether or not a vehicle exists. In FIG. 12, the data communication means 20 and the information center 2 are not shown for convenience. The above constitutes the traffic congestion prevention system 36.

FIG. 13 is a diagram corresponding to FIG. 2 of the first embodiment. In this case, if "YES" is determined in step S3, the control device 10 determines whether or not the preceding vehicle detection sensor 35 has detected the preceding vehicle in front of the own vehicle (step S8). If the preceding vehicle is detected (YES), the process proceeds to step S4, and if the preceding vehicle is not detected, a vehicle speed maintenance command is output to the vehicle control device 34 and a voice message to that effect is output (step). S9). Then, the vehicle control device 34 receives the above command and adjusts the opening degree of the throttle so as to maintain the speed of the vehicle. In addition, the voice message outputs a voice message such as "Now, in order to prevent the occurrence of traffic congestion, a command for maintaining the running speed is being output."

As described above, according to the sixth embodiment, when the preceding vehicle does not exist in the predetermined area on the front side of the own vehicle, the control device 10 notifies the message of maintaining the traveling speed of the own vehicle and the self. Since the control command for maintaining the current running speed of the vehicle is output to the vehicle control device 34, the safety in front of the own vehicle can be ensured even if the driver does not actively perform the driving operation for maintaining the running speed. After confirmation, the running speed will be automatically maintained.

(7th Example) FIG. 14 is a seventh embodiment of the present invention. The seventh embodiment shows a case where the point A on the map data in the map data input unit 8 on the navigation device 3 side is updated by the data transmitted from the information center 2. When the ACC (accessory) is turned on in the key switch of the vehicle, the navigation device 3 is turned on and activated (step S51). Then, the control device 10 requests the information center 2 to transmit the latest A point information together with its own ID (step S52).

When the information center 2 receives the transmission request (update request) (step S61), the information center 2 transmits the latest point A information held at that time to the vehicle-mounted device X side (step S62). Then, the on-board unit X determines whether or not there is a difference between the point A information of the map data input unit 8 and the point A information transmitted from the information center 2 (step S53), and if there is a difference (step S53). YES) Update the A point information of the map data input unit 8 (step S54).

As described above, according to the seventh embodiment, when the control device 10 requests the information center 2 to transmit information such as a traffic jam occurrence prediction point, the information center 2 is held by itself at that time. Information such as the predicted location of traffic congestion is transmitted. Then, when the control device 10 receives the transmitted information, the control device 10 updates the information such as the traffic jam occurrence prediction point in the map data input unit 8. Therefore, even if the predicted location of traffic congestion disappears due to a change in road conditions or a new one occurs, the information of the map data storage means on the vehicle-mounted device side can be maintained in the latest state.

The present invention is not limited to the examples described above or in the drawings, and the following modifications or extensions are possible. Only one of the transmitter / receiver 13 and the data communication means 20 may be provided. For example, in the first embodiment, step S4 may be executed without determining step S3. The third to sixth embodiments may be applied to the congestion prediction interval as in the second embodiment . Of course, both the traffic jam prediction point and the traffic jam prediction section may be handled. The sixth embodiment may be applied to the case where the traveling speed is reduced as in the third embodiment. Further, in the sixth embodiment, the display by the pace car display 50 may be automatically performed.

In the drawing, 1 is a traffic jam prevention system, 2 is an information center (traffic information center), 3 is a vehicle navigation device (traffic jam prevention device, in-vehicle device), 4 is a position detector (current position acquisition means), and 8 is. Map data input unit (map data storage means), 10 is a control device (control means, notification means, control command output means), 12 is a display device (notification means), 13 is a transmitter / receiver (traffic information acquisition means), 14 is Voice controller (notification means), 15 is speaker (notification means), 20 is data communication means (traffic information acquisition means), 30 is vehicle speed sensor (speed detection means), 31 is VICS center (traffic information center), 32 is vehicle Navigation device (traffic jam prevention device, in-vehicle device), 34 is vehicle control device (vehicle control means), 35 is preceding vehicle detection sensor (preceding vehicle detection means), 36 is traffic jam prevention system, 50 is pace car indicator ( Vehicle speed maintenance vehicle notification means) is shown.