JP2006177753A - Route guidance system and route guidance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a vehicle to travel smoothly along a search route. <P>SOLUTION: This system has a road state information acquisition processing means for acquiring road state information showing the road state fluctuating according to existence of vehicles parked on the road relative to each road link, a cost changing processing means for changing link cost based on the road state information, and a search processing means for searching for a route based on the changed link cost. Since the link cost is changed based on the road state information and the route is searched for based on the changed link cost, the vehicle can travel smoothly along the search route. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a route guidance system and a route guidance method.

  Conventionally, in a navigation apparatus, for example, the current position of a vehicle, that is, the current position is detected by GPS (Global Positioning System), and the direction of the vehicle, that is, based on the turning angle of the vehicle detected by a gyro sensor, that is, The vehicle direction is detected, map data is read from the data recording unit, a map screen is formed on the display unit, the vehicle position indicating the current location, a map around the vehicle position, and the vehicle The direction is displayed. Therefore, the driver who is an operator can drive the vehicle according to the own vehicle position displayed on the map screen, the map around the own vehicle position, and the own vehicle direction.

  When the driver inputs a destination and sets search conditions, a route search process is performed based on the search conditions, and a route from the starting point represented by the current location to the destination is searched according to the map data. Is done. The searched route, that is, the searched route is displayed together with the vehicle position on the map screen. Therefore, the driver can drive the vehicle along the displayed search route.

By the way, in general, when the number of lanes of the road link is large, the vehicle can be smoothly driven, whereas when the number of lanes of the road link is small, the vehicle can be smoothly driven. Can not. Therefore, a navigation device is provided that searches for a route by calculating a link cost in consideration of the number of lanes of road links when searching for the route (see, for example, Patent Document 1).
JP 2002-62152 A

  However, in the conventional navigation device, for example, in a two-lane road link, even when only one lane can actually pass due to on-street parking or the like, the route is assumed to be able to pass two lanes. Therefore, the road condition on the map data is different from the actual road condition, and the vehicle may not be able to travel smoothly along the searched route.

  FIG. 2 is a diagram for explaining route search processing in a conventional navigation apparatus.

  In the figure, r1-r9 are road links, of which road links r3, r4, r6 are one-lane road links with one lane, road links r1, r2, r5, r7-r9 are lanes. The two-lane road links p1 to p7 having two numbers are locations where road parked vehicles exist (hereinafter referred to as “vehicle parking locations”). In searching for a route, since the road links r3, r4, r6 are one-lane road links, the link cost is increased, and the road links r1, r2, r5, r7-r9 are two-lane road links. The link cost is lowered.

  In this case, on the road links r2, r7, r8, there are vehicle parking points p1, p2, p5-p7, so that the link cost can be lowered even though only one lane can pass. As a result, in the route search process, the search route Rt1 including the road links r1, r2, r5, r7, r9 is obtained. Therefore, when the vehicle is driven along the road link r7 on the searched route Rt1, the vehicle cannot be smoothly driven at the vehicle parking locations p1, p2, p5, and p6.

  It is an object of the present invention to provide a route guidance system and a route guidance method that can solve the problems of the conventional navigation device and can smoothly drive a vehicle along a searched route.

  Therefore, in the route guidance system according to the present invention, road condition information acquisition processing means for acquiring road condition information representing a road condition that fluctuates with the presence of a road parked vehicle for each road link, and based on the road condition information Cost change processing means for changing the link cost and search processing means for searching for a route based on the changed link cost.

  According to the present invention, the link cost is changed based on the road condition information, and the route is searched based on the changed link cost. Therefore, the vehicle can be smoothly driven along the searched route.

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

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

  In FIG. 1, 14 is an information terminal, for example, a navigation device as an in-vehicle device mounted on a vehicle, 63 is a network, 51 is an information center as an information provider, and the navigation device 14, network 63, information center 51 Etc. constitute a navigation system.

  The navigation device 14 includes a GPS sensor 15 as a current location detection unit for detecting a current location, a data recording unit 16 as an information recording unit in which various information is recorded in addition to map data, and navigation based on the input information. A navigation processing unit 17 that performs various arithmetic processing such as processing, a direction sensor 18 that serves as a direction detection unit that detects the vehicle direction, and a first input for performing predetermined input when operated by a driver as an operator. An operation unit 34 as an input unit, various displays by an image displayed on a screen (not shown), a display unit 35 as a first output unit for notifying the driver, and a predetermined input by voice A voice input unit 36 as a second input unit, a voice output unit 3 as a second output unit for performing various displays by voice and notifying the driver , And a communication unit 38 as a transmission / reception unit functioning as a communication terminal. The navigation processing unit 17 includes a GPS sensor 15, a data recording unit 16, an orientation sensor 18, an operation unit 34, a display unit 35, a voice input unit 36, An audio output unit 37 and a communication unit 38 are connected.

  The navigation processing unit 17 includes a forward monitoring device 48 that monitors the front of the vehicle, a display line recognition device 49 that recognizes a display line that divides the road lane, a peripheral monitoring device 50 that monitors the periphery of the vehicle, and the like. Connected.

  Further, a sensor unit 40 as a vehicle information detection unit is connected to the navigation processing unit 17, and the sensor unit 40 detects the operation of the winker lever by the driver for moving the vehicle to the side. Turn signal sensor 41 as a direction movement operation detection unit, an accelerator sensor 42 as an engine load detection unit that detects an operation of an accelerator pedal by a driver, a brake sensor 43 as a brake detection unit that detects an operation of a brake pedal by the driver, A vehicle speed sensor 44 as a vehicle speed detection unit for detecting a vehicle speed, a throttle opening sensor 45 as a throttle opening detection unit for detecting a throttle opening indicating an acceleration request by the driver, and a steering operation as a steering member by the driver. The steering sensor 46 as a steering detection unit to detect, and the driver Including a shift position sensor 47 as a speed change operation detecting section for detecting a range selected by operating the shift operation section and the like. The shift position sensor 47 detects that a neutral range (N), a forward range (D), a low range (L), a reverse range (R), and a parking range (P) are selected. The winker sensor 41, the accelerator sensor 42, the brake sensor 43, the steering sensor 46, the shift position sensor 47, and the like constitute a driver operation information detection unit that detects vehicle operation information by the driver.

  The GPS sensor 15 detects the current location on the earth by receiving radio waves generated by an artificial satellite, and also detects the time. In the present embodiment, the GPS sensor 15 is used as the current position detection unit, but a distance sensor, a steering sensor, an altimeter, etc. (not shown) are used alone or in combination instead of the GPS sensor 15. You can also Further, a gyro sensor, a geomagnetic sensor, or the like can be used as the direction sensor 18.

  The data recording unit 16 includes a map database including map data files, and map data is recorded in the map database. The map data includes intersection data related to intersections, node data related to nodes, road data related to road links, search data processed for searching, facility data related to facilities, and the like. The data recording unit 16 also records data for outputting predetermined information by the audio output unit 37.

  Further, the data recording unit 16 includes a statistical database composed of statistical data files, a travel history database composed of travel history data files, and the like. Statistical data is stored in the statistical data file, and travel history data is stored in the travel history data file. However, both are recorded as performance data.

  The statistical data is a history of traffic information such as traffic jam information provided in the past, that is, history information representing a history, traffic information provided in the past by the road traffic information center, etc., and provided by the Ministry of Land, Infrastructure, Transport and Tourism. Data representing traffic volume by the road traffic census (hereinafter referred to as “road traffic census information”), road timetable information provided by the Ministry of Land, Infrastructure, Transport and Tourism, and the information center 51 are a plurality of vehicles (own vehicle or other vehicle). It is created by using probe data, which is travel history data collected from the above, alone or in combination, processing as necessary, and performing statistical processing. In the statistical data, it is possible to add traffic jam prediction information for predicting a traffic jam status to the history information. In that case, in creating the statistical data, detailed conditions such as date and time, day of the week, weather, various events, seasons, facility information (presence / absence of large facilities such as department stores and supermarkets) are added to the history information.

  The data items of the statistical data include a route on which the vehicle has traveled in the past, that is, link number data (ID) for each road link that constitutes each travel route, a direction flag that represents the travel direction, and information that represents the type of information. Type, congestion level indicating the degree of congestion at each predetermined timing, link required time indicating the required time for each predetermined timing when traveling on each road link, average of the link required time for each day of the week Data (for example, day average data). In the present embodiment, the degree of traffic jam is used as a traffic jam index indicating the level of traffic jam, and is represented by traffic jam, congestion, and non-jamming.

  In addition, the travel history data is calculated and accumulated based on the travel record of the vehicle, that is, data (travel data) representing the travel record on the travel route. The data items of the travel history data include a link required time at each predetermined timing when traveling on each road link, a traffic congestion level at each predetermined timing when traveling on each road link, and the like.

  The data recording unit 16 includes a disk (not shown) such as a hard disk, a CD, a DVD, and an optical disk for recording the various data, and a read / write for reading and writing various data. A head (not shown) such as a writing head is provided. A memory card or the like can be used for the data recording unit 16.

  The navigation processing unit 17 includes a CPU 31 as a control device that controls the entire navigation device 14, a RAM 32 used as a working memory when the CPU 31 performs various arithmetic processes, a control program, A ROM 33 in which various programs for searching for routes to the ground and guidance of the route to be searched by the driver, that is, route guidance, etc. are recorded, a flash (not shown) used for recording various data, programs, etc. Provide memory.

  In the present embodiment, various programs can be recorded in the ROM 33 and various data can be recorded in the data recording unit 16, but the programs, data, and the like can also be recorded on a disk or the like. In this case, the program, data, etc. can be read from a disk or the like and written to the flash memory. Therefore, the program, data, etc. can be updated by exchanging the disk or the like. Further, when an automatic transmission control device is mounted to control an automatic transmission (not shown) mounted on the vehicle, the control program, data, etc. for the automatic transmission control device are also stored in the disk or the like. Can be recorded. Furthermore, the program, data, and the like can be received via the communication unit 38 and written to the flash memory.

  The operation unit 34 is operated by the driver to correct the current location at the start of traveling, to input a departure point and a destination, to input a passing point, and to activate the communication unit 38. As the operation unit 34, a keyboard, a mouse, or the like disposed independently of the display unit 35 can be used. Further, as the operation unit 34, a predetermined input operation is performed by touching or clicking an image operation unit such as various keys, switches, and buttons displayed as images on the screen formed in the display unit 35. It is possible to use a touch panel that can be used.

  A display can be used as the display unit 35. Then, on various screens formed on the display unit 35, the vehicle position indicating the current location, a map, a searched route, guidance information along the searched route, traffic information, etc. are displayed, or until the next intersection in the searched route. In addition to displaying the distance and the direction of travel at the next intersection, the operation guidance, operation menu, and key guidance of the image operation unit, operation unit 34, voice input unit 36, etc. can be displayed. A multiplex broadcast program or the like can be displayed.

  The voice input unit 36 includes a microphone (not shown) and the like, and can input necessary information by voice. Further, the voice output unit 37 includes a voice synthesizer and a speaker (not shown), and the search route, guidance information, traffic information, and the like are output from the voice output unit 37, for example, as voice synthesized by the voice synthesizer. .

  The communication unit 38 transmits various information such as current traffic information and general information transmitted from a road traffic information center (not shown) such as a VICS (registered trademark: Vehicle Information and Communication System) center as an information provider. A beacon receiver for receiving as a radio beacon, an optical beacon, etc. via a radio beacon device, an optical beacon device, etc. disposed along the FM, an FM receiver for receiving as an FM multiplex broadcast via an FM broadcast station, etc. Is provided. The traffic information includes traffic jam information, regulation information, parking lot information, traffic accident information, service area congestion status information, and the like, and general information includes news, weather forecasts, and the like. The beacon receiver and the FM receiver are unitized and arranged as a VICS receiver, but can be arranged separately.

  The traffic information specifies an information type indicating the type of information, secondary mesh X and Y data for specifying a secondary mesh as a mesh, and a road link connecting between two points (for example, an intersection). And link number data indicating whether the traffic is uplink / downlink or link information indicating the content of information provided in association with the link number data. For example, when the traffic information is traffic jam information, the link information Is the traffic jam head data representing the distance from the start point of the road link to the head of the traffic jam, the traffic jam degree representing the degree of traffic jam, the traffic jam length representing the distance from the traffic jam head to the traffic jam end, and the link duration Etc.

  The communication unit 38 can also receive various information such as traffic information and general information from the information center 51.

  For this purpose, the information center 51 includes a server 53, a communication unit 57 connected to the server 53, a database (DB) 58 as an information recording unit, and the like. The server 53 includes a CPU 54, a RAM 55, ROM 56 etc. are provided. The database 58 records data similar to the various data recorded in the data recording unit 16, such as the map data, statistical data, and travel history data. Furthermore, the information center 51 can provide travel history data collected from a plurality of vehicles (own vehicle or other vehicle) in real time.

  In this embodiment, the data recording unit 16 is provided with the map database, statistical database, travel history database, and the like. However, in the information center 51, the map database, statistical database, etc. A travel history database or the like can also be provided.

  The forward monitoring device 48 includes a radar such as a laser radar, a millimeter wave radar, an ultrasonic sensor, or the like, or a combination thereof. As the vehicle surrounding information, an inter-vehicle distance, an inter-vehicle time, an approach speed to a preceding vehicle, a temporary stop point ( The approach speed to the priority road from the non-priority road, the level crossing, the intersection where the red light blinks, etc.), the approach speed to the obstacle, etc. are calculated, and the preceding vehicle, the temporary stop point, the obstacle, etc. are monitored. In addition, the surroundings monitoring device 50 is a camera such as a CCD, C-MOS, etc., as a vehicle surrounding information. The vehicle is processed by processing the image data of the photographed object image to determine the state of the intersection, the number of surrounding vehicles, the position of the display line, the position of the stop line, the position of the road sign, the color of the traffic light, etc. Monitor the surroundings.

  The navigation system, the navigation processing unit 17, the CPUs 31, 54, and the like function as a computer based on various programs, data, and the like. The data recording unit 16, RAMs 32 and 55, ROMs 33 and 56, database 58, flash memory, and the like constitute a recording medium. An MPU or the like can be used instead of the CPUs 31 and 54 as the arithmetic unit.

  Next, a basic operation when the navigation system having the above configuration is used as a route guidance system will be described.

  First, when the operation unit 34 is operated by the driver and the navigation device 14 is activated, a navigation initialization processing unit (not shown) of the CPU 31 performs navigation initialization processing, and the current location and direction sensor detected by the GPS sensor 15. 18 reads the vehicle direction detected by 18 and initializes various data. The matching processing means (not shown) of the CPU 31 performs matching processing, and based on the trajectory of the read current location and the shape, arrangement, etc. of each road link constituting the road around the current location, the current location is any road. The current location is identified by determining whether it is located on the link.

  Subsequently, a basic information acquisition processing unit (not shown) of the CPU 31 performs a basic information acquisition process and reads out and acquires the map data from the data recording unit 16 or receives it from the information center 51 or the like via the communication unit 38. Get. When acquiring from the information center 51, the basic information acquisition processing means downloads the received map data to the flash memory. Moreover, when acquiring map data via the communication part 38, a program can also be acquired.

  A display processing unit (not shown) of the CPU 31 performs a display process and forms various screens on the display unit 35. For example, the road map display processing means of the display processing means performs road map display processing, forms a map screen on the display unit 35, and displays the vehicle position, a map around the vehicle position and the vehicle direction on the map screen. indicate. Therefore, the driver can drive the vehicle according to the vehicle position, the map around the vehicle position, and the vehicle direction.

  Further, when the driver operates the operation unit 34 to input a destination, a destination setting processing unit (not shown) of the CPU 31 performs a destination setting process to set the destination. It is also possible to input and set the departure place as necessary. Moreover, a predetermined point can be registered in advance, and the registered point can be set as a destination. Subsequently, when the driver operates the operation unit 34 to input a search condition, a search condition setting processing unit (not shown) of the CPU 31 performs a search condition setting process to set the search condition.

  When the destination and search conditions are set in this way, the route search processing means (not shown) of the CPU 31 performs route search processing, reads the current location, destination, search conditions, and the like from the data recording unit 16. Based on the current location, the destination, and the search data, a route from the departure point to the destination represented by the current location is searched based on the search condition, and route data representing the searched route is output. In this case, the route having the smallest total link cost assigned to each road link is set as the searched route.

  Subsequently, a guidance processing means (not shown) of the CPU 31 performs guidance processing and provides route guidance. For this purpose, the route display processing means of the guidance processing means performs route display processing, reads the route data, and displays the searched route on the map screen according to the route data. In this case, if necessary, the voice output processing means of the guidance processing means performs voice output processing and outputs a search route by voice from the voice output unit 37 to perform route guidance.

  The information center 51 can perform route search processing. In that case, the CPU 31 transmits the current location, the destination, search conditions, and the like to the information center 51. When the current center, destination, search conditions, etc. are received at the information center 51, route search processing means (not shown) of the CPU 54 performs route search processing similar to the CPU 31, reads out the search data from the database 58, and the present location, destination Based on the location and the search data, a route from the departure point to the destination is searched under the search conditions, and route data representing the searched route is output. Subsequently, a transmission processing unit (not shown) of the CPU 54 performs transmission processing and transmits the route data to the navigation device 14. Therefore, in the navigation device 14, when the basic information acquisition processing means receives the route data from the information center 51, the guidance processing means performs route guidance as described above.

  By the way, when the route search processing means searches for a route, a two-lane road link can pass two lanes even if only one lane can actually pass due to on-street parking or the like. When a route is searched for, the road condition on the map data and the actual road condition are different, and the vehicle may not be able to travel smoothly along the searched route.

  Therefore, in the present embodiment, when searching for a route, the link cost is changed in consideration of the on-street parking status of each road link, and the route is searched based on the changed link cost.

  FIG. 3 is a flowchart showing the operation of the route search processing means in the embodiment of the present invention, FIG. 4 is a first diagram for explaining the route search processing in the embodiment of the present invention, and FIG. 5 is an embodiment of the present invention. It is a 2nd figure explaining the route search process in.

  The road condition information acquisition processing means of the route search processing means performs road condition information acquisition processing, and road data, roads are obtained from the data recording unit 16 as road condition information representing road conditions that vary with the presence of a road parked vehicle. The traffic census information is obtained by reading out data or the like processed so as to correspond to the road link of the map data. In this case, the road data includes design data for each road link, for example, speed limit for each road link, number of lanes, width, road type, and the like. The data obtained by processing the road traffic census information so as to correspond to the road link of the map data is represented by the link number data of the road link and the number of road parked vehicles within a predetermined distance (100 [m]). The number of vehicles parked on the road, the number of lanes for each road link, vehicle parking locations, width, etc. are included.

  The road condition information acquisition processing means can acquire the road condition information by reading output, data, and the like representing the road condition from the forward monitoring device 48, the display line recognition device 49, and the peripheral monitoring device 50. In this case, for example, the number of vehicles parked on the road is calculated based on the output of a radar such as a laser radar or millimeter wave radar in the forward monitoring device 48 or an ultrasonic sensor or a combination thereof, or the display line in the display line recognition device 49 is displayed. The number of lanes can be calculated based on the recognition of the vehicle, or the number of vehicles parked on the road, the number of lanes, etc. can be calculated based on the camera data in the periphery monitoring device 50.

  The road condition information acquisition processing means can be acquired by reading road condition information collected by the information center 51 and transmitted from the information center 51. In this case, as described above, the road condition information acquired in each vehicle is transmitted to the information center 51, and the information center 51 transmits the collected road condition information to each vehicle.

  Subsequently, the cost change processing means of the route search processing means performs a cost change process, and changes the link cost based on the acquired road condition information.

  For example, the cost change processing means can change the link cost based on the number of lanes of the road link in road condition information when a road parked vehicle exists on a predetermined road link. In this case, the cost change processing means determines that the influence of road parking is larger as the number of lanes is smaller, and determines that the influence of road parking is smaller as the number of lanes is higher. Reduce link costs. For example, when the number of lanes is 1, the cost change processing means changes the link cost to 4 times the normal, and when the number of lanes is 2, the link cost is changed to the normal 2 times, and the lane If the number is 3 or more, the link cost is not changed.

  The link cost can be changed based on the width of the road link instead of the number of lanes of the road link. In this case, the cost change processing means determines that the influence of on-street parking is larger as the width is smaller, and increases the link cost, and determines that the influence of on-street parking is smaller as the width is larger, thereby reducing the link cost. To do.

  In FIG. 4, r11-r19 are road links, of which road links r13, r14, r16 are one-lane road links with one lane, and road links r11, r12, r15, r17-r19 are lanes. The two-lane road links p11 to p15, which are two, are vehicle parking locations. In searching for a route, since the road links r13, r14, r16 are usually one-lane road links, the link cost is increased, and the road links r11, r12, r15, r17-r19 are two-lane road links. Therefore, the link cost is lowered, but on the road links r12, r17, r18, there are vehicle parking points p11 to p15, and only one lane can pass, so the link cost is changed to twice the normal cost. . As a result, in the route search process, a search route Rt11 composed of road links r11, r13, r15, r16, r19 is obtained. Therefore, when the vehicle travels along the search route Rt11, there is no vehicle parking place, so that the vehicle can travel smoothly.

  Further, the cost change processing means, when there is a road parked vehicle on a predetermined road link, based on the vehicle parking location in the road status information, in this embodiment, from the vehicle parking location, The link cost is changed based on the distance to the nearest intersection in the vehicle, the shorter the distance from the vehicle parking location to the intersection, the greater the influence of on-street parking, the higher the link cost, the longer the distance, Judge that the impact of on-street parking is small and reduce the link cost. For example, when the distance is less than 200 [m], the cost change processing unit changes the link cost to three times the normal number of vehicles parked on the road, and the distance is 200 [m] or more. In some cases, the number of vehicles parked on the road is one, and the link cost is changed to twice the normal cost.

  In FIG. 5, r21 to r26 are road links, p21 and p22 are vehicle parking locations, and m1 and m2 are intersections. In this case, since the distance from the vehicle parking point p21 to the intersection m1 is short and less than 200 [m], the link cost is changed to three times the normal, the distance from the vehicle parking point p22 to the intersection m2 is long, 200 Since it is [m] or more, the link cost is changed to twice the normal cost. As a result, a search route Rt21 including road links r21, r24 to r26 is obtained.

  Moreover, the said cost change process means can change a link cost based on the speed limit of the road link in road condition information, when a road parking vehicle exists in a predetermined road link. In this case, the cost change processing unit determines that the higher the speed limit is, the greater the influence of road parking is, and increases the link cost. The lower the speed limit is, the lower the speed limit is, the lower the influence of road parking is. Lower. For example, when the speed limit is 30 [km / h], the cost change processing means changes the link cost to twice the normal speed, and when the speed limit is 40 [km / h] When the speed limit is 50 [km / h], the link cost is changed to 4 times the normal speed, and when the speed limit is XX [km / h], the link cost is set to the normal N Change to double.

  Further, the cost change processing means can change the link cost based on the road type of the road link in the road condition information when a road parked vehicle exists on the predetermined road link. In this case, the cost change processing means determines that the larger the road size in the road type, the greater the influence of on-street parking, and lowers the link cost in the order of the road type: national road, prefectural road, and municipal road. For example, if the road type is a national road, the cost change processing means changes the link cost to four times the normal cost, and if the road type is a prefectural road, changes the link cost to three times the normal cost. If the type is a municipal road, the link cost is changed to twice the normal cost.

  In another embodiment, the cost change processing means can set the link cost by appropriately combining the number of lanes, the width, the distance from the vehicle parking location to the intersection, the speed limit, and the like.

  In this way, when the link cost of each road link is changed, the search processing means of the route search processing means performs a search process and searches for a route with the changed link cost.

  As described above, in the present embodiment, when searching for a route, the link cost is changed in consideration of the road status information in each road link, and the route is determined according to the road status based on the link cost after the change. Since the search is performed, the vehicle can be driven while avoiding the road link where the on-street parked vehicle exists. Therefore, the vehicle can run smoothly.

Next, a flowchart will be described.
Step S1: A road condition information acquisition process is performed.
Step S2: The link cost is changed.
Step S3: A route is searched with the changed link link cost, and the process is terminated.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

It is a figure which shows the navigation system in embodiment of this invention. It is a figure explaining the route search process in the conventional navigation apparatus. It is a flowchart which shows operation | movement of the route search process means in embodiment of this invention. It is a 1st figure explaining the route search process in embodiment of this invention. It is a 2nd figure explaining the route search process in embodiment of this invention.

Explanation of symbols

14 Navigation device 17 Navigation processing unit 31, 54 CPU
51 Information Center 63 Networks r11 to r19, r21 to r26 Road links

Claims (6)

  Road condition information acquisition processing means for acquiring road condition information representing a road condition that fluctuates with the presence of a road parked vehicle for each road link; and cost change processing means for changing a link cost based on the road condition information; A route guidance system comprising: search processing means for searching for a route based on the changed link cost.   2. The route guidance system according to claim 1, wherein when there is a road parked vehicle on a road link, the cost change processing unit increases the link cost as the number of lanes of the road link decreases.   The route guidance system according to claim 1, wherein the cost change processing means changes the link cost based on a vehicle parking location when a road parked vehicle exists on the road link.   The route guidance system according to claim 3, wherein the cost change processing means changes the link cost based on a distance from the vehicle parking place to the intersection.   2. The route guidance system according to claim 1, wherein when a road parking vehicle exists on a road link, the cost change processing unit increases the link cost as the speed limit of the road link increases.   Obtain road condition information representing a road condition that fluctuates with the presence of a road parked vehicle for each road link, change the link cost based on the road condition information, and search for a route based on the changed link cost A route guidance method characterized by that.

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