JP4612678B2 - Route guidance device, route guidance method, route guidance program, and recording medium - Google Patents

Description

【Technical field】
[0001]
The present invention relates to a route guidance device, a route guidance method, a route guidance program, and a recording medium that perform route guidance to a destination point. However, the use of the present invention is not limited to the above-described route guidance device, route guidance method, route guidance program, and recording medium.
[Background]
[0002]
Conventionally, in a navigation device that searches for and guides a route to a destination, the vehicle position is recognized based on information acquired from the outside, such as sensors and GPS provided in the vehicle, and displayed on the map information. Display above. At this time, an error may occur between the vehicle position recognized by the navigation device and the map information. When such an error occurs, correct route guidance cannot be performed, so map matching is performed to correct the error and display the vehicle position so as to travel on the road of the map information.
[0003]
The basic components of the map matching are road coordinate data of map information for comparison with the direction and travel distance input of the sensor provided in the vehicle. In addition, in places where there is a difference in height, such as an elevated highway and a general road, the vehicle inclination angle calculated from the gravity applied to the vehicle and the acceleration of gravity, and a pre-recorded road Based on the inclination information, matching to a position with higher accuracy is performed (for example, see Patent Document 1 below).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-253373
DISCLOSURE OF THE INVENTION
[Problems to be solved by the invention]
[0005]
However, according to the above-described prior art, due to an error in map information, an error in sensor output, and the like, between the place where the vehicle actually exists and the predicted position of the vehicle (hereinafter referred to as a candidate) predicted by the navigation device. An error may occur. In the case of a place where there is a height difference, the data used for map matching is three-dimensional, and there are many factors that cause an error compared to a place where there is a height difference. As described above, when a deviation occurs between the actual position of the own vehicle and the candidate, an example is a problem that accurate map matching cannot be performed.
Means for solving the problem
[0006]
In order to solve the above-described problems and achieve the object, a route guidance device according to the invention of claim 1 includes position acquisition means for acquiring a plurality of candidate positions that are candidates indicating the current position of a vehicle, and the predetermined section. Inclination angle calculation means for calculating the inclination angle of the vehicle, and inclination angle acquisition means for acquiring information related to the inclination angle of the road in a fixed section that is equal to or greater than the predetermined section around the plurality of candidate positions acquired by the position acquisition means. And a pattern indicated by the inclination angle of the predetermined section calculated by the inclination angle calculation means, and a pattern included in the information regarding the inclination angle of the road of the fixed section acquired by the inclination angle acquisition means And calculating a correction value using one of the plurality of candidate positions as a candidate for determination, and correcting the plurality of candidate positions using the correction value. The correction means that repeats until all of the complementary positions are candidates for determination, and the inclination angle of the predetermined section acquired by the inclination angle acquisition means from all the candidate positions corrected by the correction means And determining means for determining the candidate position showing the pattern most similar to the pattern as the current position of the vehicle, and control means for controlling each means.
[0007]
According to a sixth aspect of the present invention, there is provided a route guidance method for obtaining a plurality of candidate positions, which are candidates indicating the current position of a vehicle, in the route guidance method of a route guidance device that performs route guidance to a destination point. And an inclination angle calculating step for calculating an inclination angle of the vehicle in a predetermined section, and information on a road inclination angle in a predetermined section that is equal to or greater than the predetermined section around the plurality of candidate positions acquired by the position acquisition step. Included in the information about the inclination angle acquisition step to be acquired, the pattern indicated by the inclination angle of the predetermined section calculated by the inclination angle calculation step, and the information about the road inclination angle of the certain section acquired by the inclination angle acquisition step A correction value is calculated using one of the plurality of candidate positions as a determination target candidate based on a comparison result with the pattern to be determined, and the plurality of candidates are calculated using the correction value. The process of correcting the position is repeatedly acquired from the correction step in which all of the plurality of candidate positions are candidates for determination, and the inclination angle acquiring step from all the candidate positions corrected in the correction step. And a determining step of determining the candidate position indicating the pattern most similar to the pattern indicated by the inclination angle of the fixed section as the current position of the vehicle.
[0008]
A route guidance program according to a seventh aspect of the invention causes a computer to execute the route guidance method according to the sixth aspect.
[0009]
A recording medium according to an eighth aspect of the present invention is readable by a computer that records the route guidance program according to the seventh aspect.
[Brief description of the drawings]
[0010]
FIG. 1 is a block diagram of a functional configuration of a route guidance device according to an embodiment.
FIG. 2 is a flowchart showing map matching processing of the route guidance device.
FIG. 3 is a block diagram of an example of a hardware configuration of the navigation device according to the embodiment.
FIG. 4 is a diagram schematically showing a positional relationship between a vehicle position and candidates.
FIG. 5 is a flowchart illustrating a map matching process performed by a route guiding unit.
FIG. 6 is a flowchart illustrating map matching processing performed by a route guidance unit.
FIG. 7 is an explanatory diagram for explaining the processing of steps S501 and S502.
FIG. 8 is an explanatory diagram for explaining the processing of steps S504 to S506.
FIG. 9 is an explanatory diagram for explaining the processing of steps S504 to S506.
FIG. 10 is an explanatory diagram for explaining the processing of steps S505 to S508.
FIG. 11 is an explanatory diagram for explaining the processing of steps S505 to S508.
FIG. 12 is an explanatory diagram for explaining the processing of steps S505 to S508.
[Explanation of symbols]
[0011]
100 Route guidance device
101 Position acquisition unit
102 Inclination angle calculation unit
103 Inclination angle acquisition unit
104 Correction unit
105 decision part
106 Display section
BEST MODE FOR CARRYING OUT THE INVENTION
[0012]
Exemplary embodiments of a route guidance device, a route guidance method, a route guidance program, and a recording medium according to the present invention will be explained below in detail with reference to the accompanying drawings.
[0013]
(Embodiment)
FIG. 1 is a block diagram of a functional configuration of the route guidance device according to the embodiment. The route guidance device 100 according to the embodiment includes a position acquisition unit 101, an inclination angle calculation unit 102, an inclination angle acquisition unit 103, a correction unit 104, a determination unit 105, and a display unit 106. Each of the constituent units 101 to 106 is controlled by a control unit (not shown) that controls each unit.
[0014]
The position acquisition unit 101 acquires a candidate position that is a candidate indicating the current position of the vehicle. Specifically, the position acquisition unit 101 calculates a candidate position based on, for example, vehicle position information received from GPS satellites and information output from the direction sensor and the vehicle speed sensor. Also, there may be a plurality of candidate positions acquired by the position acquisition unit 101.
[0015]
The inclination angle calculation unit 102 calculates the inclination angle of the vehicle. Specifically, the inclination angle calculation unit 102 calculates the inclination angle of the vehicle using, for example, an inclination angle sensor or a gyro sensor. In addition, the calculated inclination angle information is accumulated for a predetermined interval.
[0016]
The inclination angle acquisition unit 103 acquires information related to the inclination angle of the road around the candidate position acquired by the position acquisition unit 101 (the road on which the candidate is traveling). Specifically, the inclination angle acquisition unit 103 acquires, for example, road inclination angle information included in the map information. It is desirable that the information regarding the inclination angle acquired by the inclination angle acquisition unit 103 is in a certain section that is equal to or greater than a predetermined interval in which the inclination angle calculation unit 102 calculates the vehicle inclination angle. Note that when a plurality of candidate positions are acquired, information on the inclination angles of the roads around the plurality of candidate positions is acquired.
[0017]
The correction unit 104 corrects the candidate position based on the information on the inclination angle of the predetermined section calculated by the inclination angle calculation unit 102 and the information on the road inclination angle acquired by the inclination angle acquisition unit 103. Specifically, the correction unit 104, for example, the pattern indicated by the information of the inclination angle of the predetermined section calculated by the inclination angle calculation unit 102, and the road inclination angle of the fixed section acquired by the inclination angle acquisition unit 103, for example. The candidate position is corrected based on the result of comparison with the pattern included in the information regarding. When a plurality of candidate positions are acquired, the plurality of candidate positions are corrected.
[0018]
When the position acquisition unit 101 acquires a plurality of candidate positions, the determination unit 105 determines the inclination angle of a predetermined section calculated by the inclination angle calculation unit 102 from the plurality of candidate positions corrected by the correction unit 104. The candidate position indicating the pattern most similar to the pattern included in the information regarding the inclination angle of the road in the certain section acquired by the inclination angle acquisition unit 103 is determined as the current position of the vehicle. The display unit 106 displays the current position of the vehicle determined by the determination unit 105 on the map information.
[0019]
FIG. 2 is a flowchart showing map matching processing of the route guidance device. In the following description, it is assumed that there are a plurality of candidate positions that the position acquisition unit 101 acquires. First, the position acquisition unit 101 acquires a candidate position that is a candidate indicating the current position of the vehicle (step S201). Next, the inclination angle calculation unit 102 calculates the inclination angle of the vehicle in a predetermined section (step S202). In addition, the inclination angle acquisition unit 103 acquires information related to the inclination angle of the road around the candidate position (step S203).
[0020]
Then, the correction unit 104 corrects the candidate position based on the information on the inclination angle of the predetermined section calculated by the inclination angle calculation unit 102 and the information on the road inclination angle acquired by the inclination angle acquisition unit 103. (Step S204). Next, the determination unit 105 includes a pattern indicated by information on a tilt angle of a predetermined section calculated by the tilt angle calculation unit 102 from the plurality of candidate positions corrected by the correction unit 104, and the tilt angle acquisition unit 103. The candidate position indicating the pattern most similar to the pattern included in the information related to the inclination angle of the road in the certain section obtained by the above is determined as the current position of the vehicle (step S205). The display unit 106 displays the current position of the vehicle determined by the determination unit 105 on the map information (step S206), and ends the process according to this flowchart.
[0021]
As described above, according to the route guidance device 100, based on the information on the vehicle inclination angle calculated by the inclination angle calculation unit 102 and the information on the road inclination angle acquired by the inclination angle acquisition unit 103. The position of the vehicle can be obtained with higher accuracy by correcting the candidate position. In addition, since the tilt angle information is used for correction, it is possible to obtain the position of the vehicle particularly in a place where there is a height difference with high accuracy.
[0022]
Further, a comparison result between the pattern indicated by the information on the inclination angle of the predetermined section calculated by the inclination angle calculation unit 102 and the pattern included in the information on the inclination angle of the road in the certain section acquired by the inclination angle acquisition unit 103 By correcting the candidate position based on the above, it is possible to efficiently and accurately perform correction.
[0023]
In addition, the candidate position indicating the pattern most similar to the pattern indicated by the vehicle tilt angle information is determined as the current position of the vehicle from the corrected candidate positions, and is displayed on the map information. Map matching processing can be performed.
【Example】
[0024]
(Hardware configuration of navigation device 300)
FIG. 3 is a block diagram illustrating an example of a hardware configuration of the navigation device according to the embodiment. First, the hardware configuration of the navigation device 300 according to the embodiment will be described. The navigation device 300 searches for a route from the departure point to the destination point, and guides the user's vehicle along the searched route. In this example, the route guidance device 100 according to the embodiment is realized by the navigation device 300.
[0025]
In FIG. 3, the navigation device 300 is mounted on a vehicle, and includes a navigation control unit 301, a user operation unit 302, a display unit 303, a position acquisition unit 304, a recording medium 305, and a recording medium decoding unit 306. , A guidance sound output unit 307, a communication unit 308, a route search unit 309, a route guidance unit 310, a guidance sound generation unit 311, and a speaker 312.
[0026]
The navigation control unit 301 controls the entire navigation device 300. The navigation control unit 301 includes, for example, a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a ROM (Read Only Memory) that stores various control programs, and a RAM (Random Access Memory) that functions as a work area of the CPU. It is realizable with the microcomputer etc. comprised by these.
[0027]
In addition, the navigation control unit 301 inputs / outputs information regarding route guidance to / from the route search unit 309, the route guidance unit 310, and the guidance sound generation unit 311 when performing route guidance, and displays information obtained as a result thereof. And output to the guide sound output unit 307.
[0028]
The user operation unit 302 outputs information input by the user, such as characters, numerical values, and various instructions, to the navigation control unit 301. As the configuration of the user operation unit 302, various known forms such as a push button switch that detects physical pressing / non-pressing, a touch panel, a keyboard, and a joystick can be employed. The user operation unit 302 may be configured to perform an input operation by sound using a microphone that inputs sound from the outside.
[0029]
The user operation unit 302 may be provided integrally with the navigation device 300, or may be configured to be operated separately from the navigation device 300 like a remote controller. The user operation unit 302 may be configured in any one of the various forms described above, or may be configured in a plurality of forms. The user inputs information by appropriately performing an input operation according to the form of the user operation unit 302. Examples of information input by the operation of the user operation unit 302 include a destination point or a departure point of a route to be searched.
[0030]
The destination or departure point can be entered by entering the latitude / longitude and address of each point, as well as specifying the phone number, genre, keyword, etc. of the facility that will be the destination or departure point. The position can be specified. More specifically, these pieces of information are specified as a point on the map based on background type data included in map information recorded on the recording medium 305 described later. Further, map information may be displayed on the display unit 303 described later, and one point on the displayed map may be designated.
[0031]
Further, a touch panel can be adopted as the form of the user operation unit 302. When a touch panel is employed, the touch panel is used by being stacked on the display surface side of the display unit 303. The input information is recognized by managing the display timing on the display unit 303, the operation timing on the touch panel (user operation unit 302), and the position coordinates thereof. By adopting a touch panel stacked on the display unit 303 as a form of the user operation unit 302, a large amount of information can be input without increasing the size of the form of the user operation unit 302. As the touch panel, various known touch panels such as a resistance film type and a pressure sensitive type can be used.
[0032]
The display unit 303 includes, for example, a CRT (Cathode Ray Tube), a TFT liquid crystal display, an organic EL display, a plasma display, and the like. Specifically, the display unit 303 can be configured by, for example, a video I / F or a video display device connected to the video I / F. Specifically, the video I / F includes, for example, a graphic controller that controls the entire display device, a buffer memory such as a VRAM (Video RAM) that temporarily records image information that can be displayed immediately, and a graphic controller. Based on the output image information, it is configured by a control IC for controlling display of the display device. The display unit 303 displays icons, cursors, menus, windows, or various information such as characters and images. The display unit 303 displays map information and route guidance information recorded on a recording medium 305 described later.
[0033]
The position acquisition unit 304 includes a GPS receiver and various sensors, and acquires information on the current position (own vehicle position) of the own apparatus. The GPS receiver receives radio waves from a GPS satellite and obtains a geometric position with respect to the GPS satellite. GPS is an abbreviation for Global Positioning System, and is a system for accurately obtaining a position on the ground by receiving radio waves from four or more satellites. The GPS receiver includes an antenna for receiving radio waves from GPS satellites, a tuner for demodulating the received radio waves, an arithmetic circuit for calculating the current position based on the demodulated information, and the like.
[0034]
The various sensors are various sensors such as a vehicle speed sensor, an angular velocity sensor, and an acceleration (tilt) sensor that are mounted on the own vehicle and the navigation device 300, and a travel locus of the own vehicle is obtained from information output from these sensors. As described above, by using the information output from various sensors together with the information obtained from the outside by the GPS receiver, the vehicle position can be recognized with higher accuracy.
[0035]
The vehicle speed sensor is detected from the output shaft of the transmission of the vehicle on which the navigation device 300 is mounted, and outputs a pulse signal having a predetermined cycle. Therefore, since the pulse signal is synchronized with the rotation of the wheel, the travel distance can be calculated according to the number of pulses by counting the number of pulses and considering the number of pulses per one rotation of the wheel. . The angular velocity sensor detects an angular velocity when the host vehicle is rotating, and outputs angular velocity information and relative orientation information. The acceleration (tilt) sensor detects and outputs the gravitational acceleration applied to the vehicle. Therefore, the tilt angle can be detected from the output of the acceleration (tilt) sensor.
[0036]
The route guidance unit 310 described later corrects the position of the vehicle based on information on the tilt angle accompanying the movement of the vehicle (hereinafter referred to as tilt angle information) from information output from the angular velocity sensor and the acceleration (tilt) sensor. And map matching.
[0037]
The recording medium 305 records various control programs and various information in a state readable by a computer. The recording medium 305 accepts writing of information by the recording medium decoding unit 306 and records the written information in a nonvolatile manner. The recording medium 305 can be realized by, for example, HD (Hard Disk). The recording medium 305 is not limited to the HD, and can be attached to and detached from the recording medium decoding unit 306 such as a DVD (Digital Versatile Disk) or a CD (Compact Disk) instead of or in addition to the HD. A medium having portability may be used as the recording medium 305. The recording medium 305 is not limited to a DVD and a CD, but can be attached to and detached from a recording medium decoding unit 306 such as a CD-ROM (CD-R, CD-RW), MO (Magneto-Optical disk), or memory card. Media with portability can also be used.
[0038]
The map information recorded on the recording medium 305 includes background data representing features (features) such as buildings, rivers, and the ground surface, and road shape data representing the shape of the road. It is drawn in two or three dimensions on the screen. When the navigation apparatus 300 is guiding a route, the map information recorded on the recording medium 305 and the vehicle position acquired by the position acquisition unit 304 are displayed in an overlapping manner.
[0039]
The background data includes background shape data representing the shape of the background and background type data representing the type of the background. The background shape data includes, for example, feature representative points, polylines, polygons, feature coordinates, and the like. The background type data includes, for example, text data representing the name, address, and telephone number of a feature, and type data of a feature such as a building, river, or ground surface.
[0040]
The road shape data is a road network having a plurality of nodes and links connecting the nodes. The node indicates an intersection where a plurality of roads such as a three-way road such as a T-shaped road, a cross road, and a five-way road intersect. The link indicates a road. Some links have shape interpolation points, and curved roads can be expressed by these shape interpolation points.
[0041]
In addition to the road shape on the plane, the road shape data includes road inclination angle information, and together with the data output from the position acquisition unit 304, the road shape data is used in places where there is a height difference such as a three-dimensional intersection. The vehicle position can be recognized.
[0042]
The road shape data further includes traffic condition data. The traffic condition data includes, for example, the presence or absence of signals and pedestrian crossings, the presence or absence of highway doorways and junctions, the length (distance) of each link, vehicle width, direction of travel, road type (highway) , Toll roads, general roads, etc.). In the traffic condition data, past traffic information obtained by statistically processing past traffic information based on seasons, days of the week, large holidays, and times is recorded.
[0043]
In this embodiment, the map information is recorded on the recording medium 305. However, the present invention is not limited to this. The map information is not recorded only on the one provided integrally with the hardware of the navigation device 300, and may be provided outside the navigation device 300. In that case, the navigation apparatus 300 acquires map information via a network through the communication unit 308, for example. The acquired map information is recorded in a RAM or the like.
[0044]
The recording medium decoding unit 306 controls reading / writing of information with respect to the recording medium 305. For example, when HD is used as the recording medium 305, the recording medium decoding unit 306 is an HDD (Hard Disk Drive). Similarly, when a DVD or CD (including CD-R and CD-RW) is used as the recording medium 305, the recording medium decoding unit 306 is a DVD drive or a CD drive. When a CD-ROM (CD-R, CD-RW), MO, memory card, or the like is used as the writable and detachable recording medium 305, information is written into the various recording media 305 and the various recording media 305 are used. As a recording medium decoding unit 306, a dedicated drive device that can read information recorded in the recording medium is used as appropriate.
[0045]
The guide sound output unit 307 reproduces the guide sound by controlling the output to the connected speaker 312. There may be one speaker 312 or a plurality of speakers 312. Specifically, the guidance sound output unit 307 can be realized by an audio I / F connected to an audio output speaker 312. More specifically, the audio I / F includes, for example, a D / A converter that performs D / A conversion of audio digital information, an amplifier that amplifies an audio analog signal output from the D / A converter, and an audio analog signal. And an A / D converter that performs A / D conversion.
[0046]
The communication unit 308 includes, for example, an FM tuner, a VICS / beacon receiver, a wireless communication device, and other communication devices, and performs communication with other communication devices. Examples of information acquired by the communication unit 308 include road traffic information such as traffic jams and traffic restrictions. The reception of the road traffic information by the communication unit 308 may be performed at the timing when the road traffic information is distributed from the VICS (Vehicle Information and Communication System) center, or the road traffic information is periodically requested from the VICS center. You may go on. Moreover, you may make it acquire the road traffic information of a desired area via a network from the VICS information of the whole country collected by the server.
[0047]
The route search unit 309 searches for an optimal route from the departure point to the destination point using map information recorded in the recording medium 305, VICS information acquired via the communication unit 308, and the like. Here, the optimum route is a route that best matches the condition specified by the user. In general, there are an infinite number of routes from a departure point to a destination point. For this reason, items considered in route search are set to search for a route that matches the condition.
[0048]
As the departure point of the route searched by the route search unit 309, the current position acquired by the position acquisition unit 304 or the departure point designated by the user from the user operation unit 302 is set. In addition to the destination point input by the user, the facility searched from the map data by genre search or the like may be set as the destination point.
[0049]
The route guidance unit 310 adds the guidance route information searched by the route search unit 309, the vehicle position information acquired by the position acquisition unit 304, and the map information obtained from the recording medium 305 via the recording medium decoding unit 306. Based on this, real-time route guidance information is generated. The route guidance information generated at this time may be information that considers the traffic jam information received by the communication unit 308. The route guidance information generated by the route guidance unit 310 is output to the display unit 303 via the navigation control unit 301.
[0050]
The route guidance unit 310 is based on various data acquired by various sensors that constitute the position acquisition unit 304 and map information obtained from the recording medium 305 via the recording medium decoding unit 306 when performing route guidance. It calculates which location on the map the vehicle is traveling. At this time, various types of data acquired by the position acquisition unit 304 are corrected, and map matching is performed to correct the vehicle position so that the vehicle travels on the road of the map information. In particular, in places where there is a height difference, accurate map matching is performed using the inclination information of the vehicle. Details of the map matching process performed by the route guiding unit 310 will be described later.
[0051]
The guide sound generator 311 generates tone and voice information corresponding to the pattern. That is, based on the route guidance information generated by the route guidance unit 310, the virtual sound source corresponding to the guidance point is set and the voice guidance information is generated, and this is sent to the guidance sound output unit 307 via the navigation control unit 301. Output.
[0052]
Note that the position acquisition unit 101 and the inclination angle calculation unit 102, which are functional configurations of the route guidance device 100 according to the embodiment, include the inclination angle acquisition unit 103 and the correction unit 104 by the position acquisition unit 304 and the route guidance unit 310. The determining unit 105 realizes its function by the route guiding unit 310, the display unit 106 by the display unit 303 and the route guiding unit 310, and the control unit navigation control unit 301.
[0053]
(Map matching process of route guidance unit 310)
Next, details of the map matching processing performed by the route guiding unit 310 will be described. As described above, the route guidance unit 310 recognizes the vehicle position based on the information acquired by the position acquisition unit 304 and displays the vehicle position at one point on the map information recorded on the recording medium 305. . At that time, map matching is performed so that the vehicle position is placed on the road of the map information.
[0054]
The position acquisition unit 304 recognizes the position of the host vehicle from the GPS information and data output from various sensors provided in the host vehicle, but the data output from the various sensors has errors in calculation and output timing. There may be. This error is a relative error and is accumulated in proportion to the travel distance. As a result, a deviation may occur between the position where the vehicle is actually traveling and the vehicle position (candidate) predicted from the information acquired by the position acquisition unit 304.
[0055]
Also, map information may have an error with an actual road. When such factors overlap, the map matching performed by the route guiding unit 310 cannot be performed appropriately. In order to prevent this, the route guidance unit 310 according to the present embodiment performs processing described below to display the vehicle position at an appropriate position on the map information.
[0056]
FIG. 4 is a diagram schematically showing the positional relationship between the vehicle position and the candidates. The links L1 to L5 indicate the vehicle position R and the vehicle position candidates C1 to C3 that are actually displayed. Each of the links L1 to L3 has the same horizontal position with respect to gravity, but has a height difference such as an elevated and under the elevated, and has a different vertical position. The route guidance unit 310 predicts a plurality of candidates for the vehicle position from the information acquired by the position acquisition unit 304 and sets the most likely (high probability) candidate as the vehicle position. Candidates C1 to C3 are predictions of the vehicle position R from various data, but there is a deviation from the vehicle position R due to road errors in map information and output errors from various sensors.
[0057]
5 and 6 are flowcharts showing map matching processing performed by the route guidance unit. First, the route guidance unit 310 acquires the tilt angle information of the host vehicle and accumulates it for a certain distance (step S501). Here, the tilt angle information of the host vehicle is information on the tilt angle accompanying the movement of the host vehicle output from the position acquisition unit 304.
[0058]
In addition, the route guidance unit 310 acquires inclination information (hereinafter referred to as map inclination information) within a certain range before and after the candidate from the map information recorded by the recording medium 305 (step S502). The map inclination information may be acquired at a predetermined timing, such as when performing map matching, or may be always performed during traveling. In addition, acquisition of map inclination information is performed with respect to all candidates when there are a plurality of candidates.
[0059]
FIG. 7 is an explanatory diagram for explaining the processing of steps S501 and S502. In step S501, the inclination angle information of the vehicle position R is accumulated for the distance m0. In step S502, map inclination information in a range of a distance m2 before and after the candidate C2 is acquired. Although not shown, the map inclination information in the range of the front and rear distances m1 and m3 is acquired similarly for the candidates C1 and C3 shown in FIG.
[0060]
Returning to the description of FIG. Next, a candidate to be determined is selected from the candidates (step S503). For example, the candidate C1 shown in FIG. 4 is selected as a determination target candidate. Then, a position that is most similar to the tilt angle information of the host vehicle acquired in step S501 is detected from the map tilt information of the determination target candidate acquired in step S502 (step S504), and a correction distance is calculated (step S505). Also, the similarity between the map inclination information at the most similar position and the inclination angle information of the own vehicle is calculated (step S506), and the process proceeds to A in FIG.
[0061]
8 and 9 are explanatory diagrams for explaining the processing of steps S504 to S506. 8 and 9 show information acquired when the candidate C1 is selected as a determination target candidate in step S503. In FIG. 8, the solid line indicates the tilt angle information M0 of the vehicle position R accumulated for the distance m0. Also, what is indicated by a dotted line is the map inclination information M1 before and after the candidate C1 acquired for the distance m1. In the figure, the vertical axis represents the inclination angle, and the horizontal axis represents the distance in the horizontal direction.
[0062]
The route guiding unit 310 compares these two pieces of information and detects the most similar position (pattern comparison process). The most similar position is detected by, for example, moving the inclination angle information M0 of the own vehicle on the map inclination information M1, detecting a position having a similar data shape, and detecting the map inclination information at each position and the own vehicle. This is done by calculating the cost of each slope information and comparing the costs. In the case of the example shown in FIG. 8, as shown in FIG. 9, the position of Ma indicated by a two-dot chain line obtained by moving the tilt angle information M0 indicated by the solid line by the distance d1 is the most similar position. Thereby, the correction distance is calculated as d1. In step S506, the similarity between Ma and M1 is calculated. The similarity is calculated, for example, by calculating the cost of each data.
[0063]
In calculating the correction distance, the sum of squares of each data is taken and compared so that an error in calculation of the tilt angle information output from the acceleration (tilt) sensor does not affect the position detection. As a result, the numerical difference of the original data is emphasized, a minute error in calculation can be absorbed, and a more accurate correction distance can be calculated.
[0064]
Turning to the description of FIG. The route guiding unit 310 moves the positions of all other candidates by the correction distance calculated in step S505 (step S507). Also, the degree of similarity between the tilt angle information and the map tilt information of each candidate at the moved point is calculated (step S508). The calculation of the similarity is the same as the processing in step S506.
[0065]
FIGS. 10-12 is explanatory drawing for demonstrating the process of step S505-S508. The candidates C1 to C3 shown in FIG. 10 are the same as the candidates C1 to C3 shown in FIG. In addition, illustration of the own vehicle position R was abbreviate | omitted for convenience of description. The route guidance unit 310 calculates the correction distance d1 by the process using the candidate C1 as a candidate for determination (step 505 in FIG. 5), and calculates the similarity to the map inclination information in C1a obtained by moving the candidate C1 by the distance d1. (Step S506 in FIG. 5). Then, also for the other candidates C2 and C3, the similarity with the map inclination information at C2b and C3c moved by the distance d1 is calculated (step S508 in FIG. 6).
[0066]
FIG. 11 shows map inclination information M2 around the candidate C2. In step S508 of FIG. 6, the similarity between Mb obtained by moving the position of M0 in the candidate C2 by the distance d1 and the map inclination information at the position overlapping with Mb is calculated. Further, FIG. 12 shows map inclination information M3 around the candidate C3. Similar to FIG. 11, in step S508 of FIG. 6, the similarity between Mc obtained by moving the position of M0 in the candidate C3 by the distance d1 and the map inclination information at the position overlapping with Mc is calculated.
[0067]
The above processing is repeated with all candidates as judgment target candidates. Until all candidates are determined as candidates for determination (step S509: No), the candidates for determination are changed (step S510), the process returns to step S503, and the subsequent processing is repeated. In the illustrated example, the processes in steps S503 to S508 are repeated with the candidates C2 and C3 as candidates for determination.
[0068]
If all candidates are determined as candidates for determination (step S509: Yes), the calculated similarities of all candidates are compared (step S511). Then, the vehicle position is determined as a candidate position having the highest similarity (step S512), the determined vehicle position is displayed so as to overlap the map information (step S513), and the processing according to this flowchart is terminated.
[0069]
As described above, according to the route guidance device according to the embodiment, the position of each candidate indicating the own vehicle position is corrected by the correction distance calculated by the other candidates, and the map inclination information and the own vehicle at that position are corrected. The degree of similarity with the tilt information is calculated. And the point with the highest similarity is determined as the vehicle position. As a result, it is possible to correct the shift caused by the error of each data and perform an accurate map matching.
[0070]
In addition, the position of the candidate is corrected based on the inclination angle information of the point where the vehicle is actually traveling and the road inclination angle information (map inclination information) included in the map information. The position of the vehicle can be obtained with high accuracy.
[0071]
In the present embodiment, a process of calculating a correction value using one of a plurality of candidate positions as a determination target candidate and correcting the plurality of candidate positions using the correction value is performed for all of the plurality of candidate positions. Is repeated until it becomes a determination target candidate, and the candidate indicating the pattern most similar to the pattern indicated by the inclination angle of the certain section acquired by the inclination angle acquisition means is selected from all of the corrected candidate positions. Although what determines a position as a present position of the said vehicle was illustrated, it does not restrict to this.
[0072]
For example, a candidate with a high probability is selected as a promising candidate position from a plurality of candidates for each judgment target candidate, and the respective probable candidate positions in all judgment target candidates are compared, and the highest probability is obtained. The candidate position may be determined as the current position. Further, as in the above-described embodiment, a plurality of candidate positions may be corrected, and the candidate position with the highest probability among them may be determined as the current position.
[0073]
Furthermore, in the present embodiment, the processing until the candidate position having the highest probability from the plurality of candidate positions is determined as the current position is shown, but in addition to this, the candidate position determined as the current position of the vehicle is added. The applied correction value (e.g., d1) is applied to other candidate positions, and the position acquisition unit 304 reaches the predetermined condition based on the corrected candidate positions with respect to these other candidate positions (e.g., for each candidate position). The acquisition of the candidate position may be continued to improve the accuracy of the map matching (until it is no longer established as a map matching candidate position, such as when the cumulative value of the azimuth becomes larger than a predetermined value).
[0074]
The route guidance method described in the present embodiment can be realized by executing a program prepared in advance on a computer such as a personal computer or a workstation. This program is recorded on a computer-readable recording medium such as a hard disk, a flexible disk, a CD-ROM, an MO, and a DVD, and is executed by being read from the recording medium by the computer. The program may be a transmission medium that can be distributed via a network such as the Internet.

Claims (8)

Position acquisition means for acquiring a plurality of candidate positions which are candidates indicating the current position of the vehicle;
An inclination angle calculating means for calculating an inclination angle of the vehicle in a predetermined section;
Inclination angle acquisition means for acquiring information related to the inclination angle of a road in a fixed section that is equal to or greater than the predetermined section, around the plurality of candidate positions acquired by the position acquisition means;
Based on a comparison result between the pattern indicated by the inclination angle of the predetermined section calculated by the inclination angle calculation means and the pattern included in the information regarding the inclination angle of the road of the certain section acquired by the inclination angle acquisition means. And calculating a correction value using one of the plurality of candidate positions as a candidate for determination, and correcting the plurality of candidate positions using the correction value, all of the plurality of candidate positions are candidates for determination. Correction means to be repeated until
Among all the candidate positions corrected by the correcting means, the candidate position indicating the pattern most similar to the pattern indicated by the inclination angle of the certain section acquired by the inclination angle acquiring means is the current position of the vehicle. Determining means to determine as,
Control means for controlling each means ;
A route guidance device comprising: The position acquisition means acquires a plurality of candidate positions,
  The inclination angle acquisition means acquires information related to the inclination angles of roads around the plurality of candidate positions,
  The correction unit corrects each of the plurality of candidate positions,
  Of the plurality of candidate positions corrected by the correcting means, a pattern indicated by the inclination angle of the predetermined section calculated by the inclination angle calculating means and the road in the fixed section acquired by the inclination angle acquiring means Determining means for determining, as the current position of the vehicle, the candidate position indicating a pattern most similar to the pattern included in the information related to the inclination angle of the vehicle;
  The route guidance device according to claim 1, comprising: The correction means further applies the correction value applied to the candidate position determined as the current position of the vehicle to other candidate positions,
  2. The route guidance device according to claim 1, wherein the position acquisition unit continues to acquire the candidate position until a predetermined condition is reached based on the corrected candidate position with respect to the other candidate position. 3. The route guidance device according to claim 2, further comprising display means for displaying the current position of the vehicle determined by the determination means on map information. The position acquisition means acquires the candidate position from position information of the vehicle received from a GPS satellite and information output from an orientation sensor, a vehicle speed sensor, and an acceleration sensor mounted on the vehicle. Item 5. The route guidance device according to any one of Items 1 to 4. In the route guidance method of the route guidance device that performs route guidance to the destination point,
A position acquisition step of acquiring a plurality of candidate positions which are candidates indicating the current position of the vehicle;
  An inclination angle calculating step of calculating an inclination angle of the vehicle in a predetermined section;
  An inclination angle acquisition step of acquiring information related to an inclination angle of a road in a certain section that is equal to or greater than the predetermined section around the candidate positions acquired by the position acquisition step;
  Based on a comparison result between the pattern indicated by the inclination angle of the predetermined section calculated by the inclination angle calculation step and the pattern included in the information regarding the inclination angle of the road of the certain section acquired by the inclination angle acquisition step. And calculating a correction value using one of the plurality of candidate positions as a candidate for determination, and correcting the plurality of candidate positions using the correction value, all of the plurality of candidate positions are candidates for determination. A correction process that is repeated until
  Among all the candidate positions corrected by the correction step, the candidate position indicating the candidate position indicating the pattern most similar to the pattern indicated by the inclination angle of the certain section acquired by the inclination angle acquisition step is the current position of the vehicle. A decision step to decide as
  A route guidance method comprising: A route guidance program for causing a computer to execute the route guidance method according to claim 6. A computer-readable recording medium on which the route guidance program according to claim 7 is recorded.

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