JP2000211452A - Runway shape display device and map database recording medium - Google Patents

Abstract

(57) [Summary] [Problem] Reliably and quickly without being affected by environmental conditions,
Presents the track shape from the driver's point of view. A driving viewpoint lane shape storage unit associates each of a plurality of points on a map road with a driving viewpoint lane shape representing a front lane shape viewed from a viewpoint of a vehicle driver at each point. Remember. Preferably, the runway shape is a shape of a white line drawn on the road. The host vehicle position detection unit 18 detects the host vehicle position. The navigation control unit 10 stores the white line shape corresponding to the own vehicle position in the driving viewpoint lane shape storage unit 2.
4 and displayed on the head-up display 36. Preferably, the lateral displacement of the vehicle with respect to the runway, the lane direction and the inclination of the vehicle direction are detected, and the white line shape is corrected before displaying.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lane shape display device capable of reliably and quickly displaying the shape of a lane viewed from the driver's viewpoint, and the present invention also relates to a map database suitable for use in the display device. Related to a medium on which is recorded.

[0002]

2. Description of the Related Art When driving a vehicle, a driver visually recognizes the shape of a road ahead of the vehicle through a windshield. However, it is sometimes difficult to grasp the shape of the road ahead due to the influence of weather conditions, the curve of the road, vehicles around the building, and the like. Therefore, it is preferable that the vehicle be provided with a device that grasps the shape of the road ahead in the driver's viewpoint, and that the shape of the road be presented to the driver.

[0003] Japanese Patent Application Laid-Open No. 7-57200 discloses that a white line on a road is detected from a road image taken by a vehicle-mounted camera.
An apparatus for displaying a detected white line is disclosed. The driver can grasp the shape of the road ahead by looking at the white line displayed on the display device.

[0004]

However, it is impossible to display the shape of the road in an environment where it is difficult to take a picture with a camera, for example, in fog. Further, there are cases where a white line cannot be detected from a photographed image like a snowy road. When a large vehicle is further ahead, the white line cannot be photographed. As described above, the running condition display device using a camera has limited environmental conditions in which it functions effectively.

[0005] In fact, although it is strongly desired that the display of the road shape is strongly desired in an environment where it is difficult for the driver to visually grasp the road shape, it is difficult to detect the road shape in such an environment. It was difficult to help the driver.

[0006] In a known navigation device, a two-dimensional map of the periphery of a vehicle viewed from directly above the sky is displayed.
However, the road shape viewed from directly above is significantly different from the road shape viewed forward from the driver's viewpoint. Even looking at such a planar map, it is not easy for the driver to intuitively grasp the shape of the road ahead.

[0007] Further, a navigation device for displaying a map three-dimensionally, such as a so-called bird view, is well known.
A two-dimensional map of the vicinity of the own vehicle position viewed from directly above is displayed after being processed into a map viewed from obliquely above. However, in this type of device, screen scrolling is considerably slower than in a normal map display. This is considered to be due to a large amount of data processing because coordinate transformation such as projection transformation is performed on a large number of points, and an increase in display target data for oblique display.

At present, lane (lane) guidance on a three-dimensional display is not generally performed, but when attempting to perform lane guidance, it is required to update the display at high speed in accordance with the movement of the vehicle. . It is not easy to meet such a demand in a process that requires a large calculation load and a large amount of data to be handled.

The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to reliably and promptly present a runway shape viewed from a driver's viewpoint without being affected by environmental conditions. is there.

[0010]

In order to achieve the above-mentioned object, the present invention provides a roadway shape display apparatus comprising: a plurality of points on a map road; Road shape storage means for associating and storing a driving viewpoint road shape representing the road shape; host vehicle position detecting means for detecting the own vehicle position; display means for displaying the driving viewpoint road shape; Display processing means for reading the driving viewpoint running road shape corresponding to the own vehicle position detected by the means from the running road shape storage means and displaying the read running road shape on the display means.

According to the present invention, the driving viewpoint road shape corresponding to the own vehicle position is read from the storage device and displayed.
The road shape can be displayed even in an environment where the visibility of the driver is reduced.

Further, according to the present invention, the driving viewpoint running road shape of the corresponding point is associated with the point data of the map. That is, the driving viewpoint road shape is prepared in advance for each point. Therefore, a large amount of data processing, such as reading out a large number of point data and performing conversion processing, is not required when displaying the roadway shape, and the roadway shape from the driving viewpoint can be quickly displayed.

Preferably, the track shape storage means stores, as the driving viewpoint track shape at each position, a set of discrete representative points extracted from the track shape when the driver looks forward from the driver's viewpoint at the corresponding position. I remember. The display processing unit includes a unit that generates a continuous runway shape based on the discrete representative point set. According to this aspect, it is possible to reduce the amount of data to be stored by the lane shape storage unit. Since the driving viewpoint road shape data is prepared for each point data, it is possible to avoid a situation in which the data amount becomes enormous.

[0014] Preferably, the display processing means selects a driving viewpoint running road shape to be read out from the storage means, based on a running path around the position of the own vehicle or a planned running path. Efficient processing can be performed by selecting a runway that is likely to actually run.

[0015] Preferably, the vehicle further includes a lateral deviation detecting means for detecting a lateral deviation of the vehicle with respect to the traveling road. In the display processing means, based on the lateral deviation, the driving viewpoint lane shape corresponding to the own vehicle position read from the lane shape storing means is coordinate-converted into the lane shape seen from the laterally deviated viewpoint. As a result, it is possible to present the roadway shape that matches the actual situation to the driver. That is, the vehicle does not travel at a fixed position in the track, and the traveling position shifts in the lateral direction, and accordingly, the position of the viewpoint shifts. ADVANTAGE OF THE INVENTION According to this invention, even if the viewpoint corresponding to the memorized lane shape and the actual viewpoint deviate, the lane shape seen from the actual viewpoint can be displayed.

[0016] Preferably, the vehicle further includes an inclination detecting means for detecting an inclination of the vehicle direction with respect to the traveling road direction. In the display processing means, based on the inclination, the driving viewpoint running road shape corresponding to the own vehicle position read from the running road shape storage means is coordinate-converted into the running road shape viewed from the inclined viewpoint. This embodiment also allows the driver to be presented with a road shape that matches the actual situation. That is, although the traveling direction of the vehicle does not always coincide with the direction of the lane, according to the present invention, even if the vehicle direction assumed in the stored lane shape and the actual vehicle direction deviate, the actual The road shape ahead of the vehicle according to the situation can be displayed.

Preferably, the display means is a head-up display for displaying an image on a windshield of a vehicle. Since the driver's feeling when seeing the display of the road shape matches the actual driving feeling, the effect of assisting the driver is increased.

Preferably, the driving viewpoint lane shape is data indicating a shape of a line representing a lane drawn on the lane. The lane display line (typically, a white line) is an appropriate index indicating the shape of the road. By applying the present invention to lane guidance, the updated display can be performed at a high speed, so that the driver can be provided with easy-to-understand guidance.

Another aspect of the present invention is a map data recording medium on which a road map database is recorded. In the map database, each of several points on the road,
At each point, a driving viewpoint lane shape representing a lane shape ahead of the vehicle driver from the viewpoint is associated.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention (hereinafter, referred to as embodiments) will be described below with reference to the drawings. In the present embodiment, the track shape display device of the present invention is:
It is provided integrally with the on-vehicle navigation device.

FIG. 1 is a block diagram showing the configuration of the navigation device of the present embodiment. The navigation control unit 10 controls the entire apparatus, and performs navigation-related processes such as route calculation and route guidance. The control unit 10 also functions as a display processing unit of the present invention.

The navigation control unit 10 is connected to a GPS (global positioning system) device 12, a gyro sensor 14, and a vehicle speed sensor 16. Based on the input signals from these sensors, the vehicle position detection unit 18 of the control unit 10 obtains the position of the vehicle. As is well known, the GPS device 12 obtains the position of the vehicle from radio waves transmitted from artificial satellites. The own vehicle position is captured using the traveling direction and the speed detected by the gyro sensor 14 and the vehicle speed sensor 16. Further, the map database storage unit 20
It is also preferable to perform map matching using the map data stored in.

The navigation control unit 10 performs a navigation process using the vehicle position detected by the position detection unit 18. When the user inputs a travel destination using the input device 30, the control unit 10 searches for and sets a route from the own vehicle position to the destination. The route calculation is performed by a process such as the Dijkstra method using the map data stored in the two-dimensional map storage unit 22 of the map database storage unit 20.
A map around the own vehicle position is read from the two-dimensional map storage unit 22 and displayed on the display 32 as a display unit. The set route is displayed so as to be distinguished from other roads. In addition, a voice guidance for notifying a route at an intersection or the like is output from the speaker 34 as appropriate.

[Display of Runway Shape] As a feature of the present embodiment, the map database storage unit 20 has a driving viewpoint runway shape storage unit 24, and this storage unit 24 is an embodiment of the runway shape storage means of the present invention. It is. In the storage unit 24, each point on the road is associated with a driving viewpoint road shape according to the present invention, which represents the road shape ahead of the driver at the corresponding point as viewed from the driver's viewpoint.

With reference to FIG. 2, the information stored in the driving viewpoint lane shape storage unit 24 will be specifically described. A plurality of points a1 to a4 and b1 to b4 are set in opposite lanes A and B on the road. The storage unit 24 stores, at each point, data of a road shape viewed from the driver's viewpoint. In this embodiment,
The white line shape drawn on the road is used as runway shape information. The driver can easily grasp the road shape from the display of the white line. If a white line shape is applied, the amount of stored data and the amount of processed data can be reduced. From such a viewpoint, the white line shape is adopted as the runway shape.

In FIG. 2, at point a1 on the first lane A, the road ahead is straight. Therefore, a white line shape representing a straight line is associated with the point a1. At point a2, the road ahead is a right curve, so the white line shape of the right curve is point a2.
Is associated with On the other hand, at point b1 on the second lane B opposite to the first lane A, the road ahead is a left curve, so the white line shape of the left curve is associated with the point b1. The point b3 is associated with a straight white line shape.

Points a2 and b3 are at the same location on the road but belong to opposite lanes. Therefore, the shape of the front running road at both points a2 and b3 is different, and the stored white line shape is also different. Thus, different white line shapes are stored according to the direction of the lane.

As shown in FIG. 3, white line shape data is created and stored in advance by projection transformation. Sets the driver's perspective of a standard physique when the standard vehicle is in the center of the lane. Many points P on the white line of the road ahead of the viewpoint
1 to Pn are set. One point P1 based on the viewpoint
The point p1 (x) where (X1, Y1, Z1) is projected on the projection surface
1, y1). By the same coordinate conversion, a point to be displayed on the projection plane is obtained from other points on the white line. In this way, the front white line shape seen from the viewpoint shown in FIG. 3B is generated.

Returning to FIG. 1, when the driver operates the input device 30 to instruct the display of the lane shape, the navigation control unit 10 performs a display process of the lane shape at the driving viewpoint. First,
The vehicle position is required. Then, the white line shape stored in advance in association with the obtained position is read from the driving viewpoint lane shape storage unit 24. At this time, as described with reference to FIG. 2, the white line shape corresponding to the traveling direction of the vehicle is read. Under the control of the navigation control unit 10, the read-out white line shape is displayed on the head-up display 3.
6 is displayed. As is well known, the head-up display 36 is a device that projects an image on a windshield of a vehicle.

As described above, according to the present invention,
The road shape can be reliably displayed even under environmental conditions where the driver's visibility is low. For example, in weather such as fog, it is difficult to visually grasp the shape of the runway. Similarly, when the road is covered with snow or when there is a large vehicle ahead, it is difficult to grasp the shape of the road. In such a situation, it is difficult to grasp the road shape from the photographed image even if the scenery ahead is photographed by the camera. However, according to the present invention, the track shape is displayed using the detected vehicle position and the stored information, so that the track shape can be reliably displayed even under the above-mentioned environmental conditions.

In this embodiment, white line shape data for each point is generated and prepared in advance. Here, it is assumed that a white line shape has not been prepared in advance.
In this case, the white line shape generation processing described with reference to FIG. 3 must be performed in real time. In addition to reading out the data of the own vehicle position from the storage device, further, prefetching of data indicating a point on a white line ahead of the own vehicle position is performed. The pre-read data is subjected to coordinate transformation based on the viewpoint origin, projected and transformed on the projection plane, and the obtained image is displayed. A large amount of data processing is required, making it difficult to update the display quickly and appropriately.

On the other hand, according to the present invention, it is not necessary to pre-read the data, and only the data relating to the current position needs to be read from the storage device. This is because a white line shape viewed from the driver's viewpoint is already prepared as a part of the point data. It is not necessary to perform the coordinate conversion processing of the data group read in advance. Therefore, it is possible to quickly display the white line shape. The quick display of the white line is also suitable for providing guidance for lane change and the like.

Preferably, the navigation control unit 1
0 selects a white line shape to be read from the driving viewpoint running shape storage unit 24 based on a running route around the own vehicle position or a planned running route. The scheduled traveling route is determined from a set route used for route guidance. Efficient processing can be performed by narrowing down data read from the storage device on the basis of a running path that is likely to actually run.

In the present embodiment, the white line shape is displayed on the head-up display 36 as described above. Therefore, the driver's feeling when viewing the display of the road shape matches the actual driving feeling, so that a greater driving support effect can be obtained. Of course, the white line shape may also be displayed on the display 32. Further, in addition to the white line shape, other information such as a sign on the road and around the road may be displayed.

"Processing for a Road with Multiple Lanes" On a road having a plurality of lanes in one direction, the entire lane shape may be displayed, but it is also preferable to display the lane shape in which the own vehicle is traveling. is there. Recently, RTK (Realtime Kinematic) -GP
A highly accurate position detection technology called S has been proposed.
The lane in which the vehicle is traveling is determined using such a method.
The white line shape for each lane is stored in the driving viewpoint track shape storage unit 24, and the corresponding data is displayed.

"Processing for a road without a center line" A lane cannot be defined on a road without a center line. Therefore, for each point on the road, the white line shape when viewing in both directions is stored. Then, the white line shape corresponding to the traveling direction is read out and displayed.

[Reduction of data amount of white line shape at driving viewpoint] FIG.
Is a set of points on the projection plane. Simply storing the data of the coordinate transformation result of FIG. 3 for each point increases the amount of stored data. Therefore, the following (1)
As shown in (3) to (3), the driving viewpoint lane shape storage unit 2
It is preferable to reduce the amount of data to be stored by the storage device 4.

(1) Data is thinned out and stored Data can be reduced by appropriately thinning out data from a set of many points showing a white line shape and leaving a representative point. Referring to FIG. 4A, even if points are set at regular intervals on an actual road, the distance between points on the projection plane becomes narrower as the distance increases. Therefore, as the distance increases, many points are thinned out, and the interval between representative points is widened. For example, it is preferable to increase the interval between the representative points in order of every other, every second, every fourth, etc. in an exponential manner. By performing such processing, it is possible to effectively reduce the amount of data while maintaining a white line shape that is close to the actual appearance for the driver. When displaying a white line, the navigation control unit 10 reads the set of representative points and connects them appropriately to obtain a continuous white line shape.

(2) Calculate an approximate curve from the calculation results and store its parameters. Referring to FIG. 4B, for example, a white line shape on the projection plane is approximated to a quadratic curve or a straight line. Then, the parameters of the quadratic curve or straight line are stored. Even with such processing, the data amount can be reduced without impairing the apparent white line shape of the driver. At the time of the display processing, the navigation control unit 10 reads the above parameters as the road shape information and generates image data according to the parameters.

(3) The white line shape is approximated to several straight lines, and the coordinates of the end point and the intersection are stored. As shown in FIG. 4C, the white line shape is approximated to a plurality of straight lines. From the same viewpoint as (1), it is preferable to replace many points with one straight line as the distance increases. The end points of the front and rear straight lines and the coordinates of the intersection of the straight lines are stored as white line shapes. The form of the data is basically a representative point set similar to (1). At the time of display processing, a representative point set is read out and connected by a straight line.

In the above, (1) and (3) are one embodiment of the mode of the present invention that stores a set of discrete representative points extracted from the road shape. Navigation control unit 1
0 generates a continuous runway shape based on the representative point set.

[Correction of White Line Shape] The driving viewpoint lane shape storage unit 24 stores a white line shape to be a reference. This reference shape is a white line shape when the vehicle is at the center of the traveling lane and the direction of the lane coincides with the direction (traveling direction) of the vehicle. However, in other situations, the shape of the white line seen from the driver's viewpoint is different. Therefore, by correcting the white line shape according to the position and direction of the vehicle as described below, the actual white line shape can be matched with the image, and more convenient information can be provided to the driver. Here, it is assumed that the white line shape is configured by a set of the representative point data described above.

"Correction for Lateral Displacement (Offset) of Vehicle" First, the white line shape correction processing when the vehicle is running at a position shifted laterally from the center of the lane will be described. For the sake of simplicity, it is assumed that the road is straight and the vehicle direction matches (is parallel to) the lane direction.

FIG. 5 (a) shows a driving viewpoint lane shape storage unit 2.
4 is a reference white line shape stored in No. 4, that is, a white line shape seen from the center of the lane. On the projection plane, the interval between the two white lines is L2 on the near side and L1 on the far side. When the x-axis is set horizontally and the y-axis is set vertically, the white line is y
It is inclined by an angle α with respect to the axis.

FIG. 5B shows a white line shape that can be seen when the vehicle is assumed to be located at a position crossing the left white line. The horizontal interval between the white lines is set equal to that in FIG. The direction of the left white line coincides with the vehicle direction (= y axis).

FIG. 5C shows a white line shape seen from the driver's seat in a general situation. The actual road width is W, and the actual offset from the center of the road is Δw. When the vehicle is offset by Δw, it is assumed that the inclination angle of the left white line is α ′ on the projection plane. Using the inclination angle α of the white line of the reference data (FIG. 5A), the angle α ′ is obtained by the following equation (A-1).

[0047]

Α ′ = α × (1−Δw / (W / 2)) (A-1) By using this equation, a simple calculation can be performed at various offset positions from the reference display data. Display data can be created.

An example of a method for actually obtaining the coordinates of the two end points p1 to p4 of the two white lines in FIG. The coordinates of the point p1 before and after the correction are (x1, y1) and (x1a, y1), respectively (the same applies to the points p2 to p3). Since the lateral displacement is targeted, the correction of the y coordinate is unnecessary.

[Step 1] The center of the image is determined. The center shift amount ΔL is obtained by the following equation (A-2).

[0050]

ΔL = L2 * Δw / W (A-2) “Step 2” The display positions of the points p1 and p2 (the front end points of both white lines) are obtained. X coordinate of corrected point p1 (x1a)
From the reference x coordinate (x1) of the stored point p1,
It is determined by the following equation (A-3). Similarly, the corrected x coordinate (x2a) of the point p2 is also obtained.

[0051]

## EQU3 ## (x1a) = (x1)-. DELTA.L (A-3) "Step 3" α 'is obtained by using the above equation (A-1). Then, the x coordinate (x3a) of p3 after correction from α '
Ask for.

[0052]

(X3a) = (x1a) + sin (α ′) * (y1-y3) (A-4) “Step 4”: The point p3 obtained in step 3 is laterally separated by L1 from the point p3. The x coordinate (x4a) of the point p4 is obtained.

[0053]

## EQU5 ## x4a = x3a + L1 (A-5) As described above, since the offset is targeted, correction of the y coordinate is unnecessary. As described above, the points p1 to p1
Since the coordinates of p4 have been determined, a straight line connecting p1 and p3,
Draw a straight line connecting p2 and p4. The generated image has a white line shape corrected for the offset of the vehicle.

Although a straight road has been described for the sake of simplicity, the coordinate conversion process may be basically performed even when the road is curved. For example, the lane near the vehicle is regarded as a straight line. The inclination angle α of the white line may be obtained by the following formula.

In this embodiment, it is preferable that the amount of lateral deviation from the center of the lane be detected by using a high-accuracy positioning technique such as the above-described RTK-GPS. Further, a camera for photographing a white line or the like under the foot of the vehicle may be provided, and a lateral shift may be detected from a photographed image of the camera. If it is an image of your feet,
It is possible to shoot even in bad weather conditions such as fog.

In this embodiment, the vehicle position in the reference image is the center of the lane, but another position may be the reference.

"Correction According to Inclination of Vehicle Direction" Here, the white line shape correction processing when the vehicle direction is inclined with respect to the lane direction will be described. For the sake of simplicity, it is assumed that the vehicle is at the center of the lane and that the amount of lateral displacement is zero.
At this position, it is assumed that only the direction of the vehicle is shifted from the direction of the lane by an angle β.

Consider a music coordinate system as shown in FIG. Then, a projection plane as shown in FIG. 7 is assumed. When a viewpoint is represented by a curved coordinate system with respect to a reference point by general coordinate transformation (projection transformation), the following is obtained. The reference point (gaze point) is a reference point on the projection plane, for example, a point at the center of the screen. Here, the viewpoint is (Xv, Yv, Zv) and the reference point is (Xf,
Yf, Zf).

[0059]

Xv = r * cosθ * cosφ + Xf (B-1) Yv = r * sinθ * cosφ + Yf (B-2) Zv = r * sinφ + Zf (B -3) When the point P1 (X1, Y1, Z1) on the white line is viewed from the viewpoint, the point P1 is projected on the point p1 (x1, y1) on the projection plane. Here, Z in the following equation is the distance between the viewpoint and the reference point.

[0060]

X1 (θ) = (− (X1-Xf) * sinθ + (Y1-Yf) * cosθ) * r / (r−Z) :( B-4) y1 (θ) = (− (X1− Xf) * cosθ * sinφ− (Y1-Yf) * sinθ * sinφ + (Z1−Zf) * cosφ) * r / (r−Z): (B-5) A = − (X1−Xf) * r / (r-Z), B = (Y1-Yf) * r /
When (r−Z) is set, equation (B-4) can be rewritten as follows.

[0061]

X1 (θ) = A * sinθ + B * cosθ (B-6) As shown in FIG. 8, it is assumed that the vehicle is inclined at an angle β with respect to the lane. Think. Point p1 in this case
Is obtained by replacing the θ component of the curved coordinate in equation (B-6) with θ + β. That is, the following equation (B
-7), the x coordinate of the point p1 corresponding to the angle β is obtained.

[0062]

X1 (θ + β) = A * sin (θ + β) + B * cos (θ + β) (B-7) On the other hand, the y component of the point p1 is considered as follows.
It is considered that the range in which β can be taken is relatively narrow because high-speed display updating is required when the vehicle is traveling at a certain high speed. It is also considered that the elevation angle φ from the horizontal line is a relatively small value. Under this assumption, if θ in the above equation (B-5) is replaced with θ + β and further equation modification is performed, the following is obtained.

[0063]

Y1 (θ + β) = (− (X1−Xf) * sinφ * (cosθ * cosβ−sinθ * sinβ) − (Y1−Yf) * sinφ * (sinθ * cosβ + cosθ * sinβ) + (Z1−Zf) * Cosφ) * r / (r−Z) (B-8) Here, sinφ and sinβ are both small, so sinφ * sin
If β ≒ 0 and cos β ≒ 1, the result of the following equation (B-9) is obtained.

[0064]

Y1 (θ + β) ≒ y1 (θ) (B-9) From equation (B-9), even when the traveling direction of the vehicle is deviated from the direction of the lane, y of the point on the white line is obtained. No coordinate correction is required. Even if the y-coordinate of the reference data is used as it is, the shape of the displayed white line and the actual white line are similar and look the same to the driver.

In order to smoothly perform the above processing, point data (A, B, y) constituting a white line is stored in the driving viewpoint lane shape storage unit 24. That is, one point is
It is associated with a set of point data (A, B, y) on the white line seen from there. A and B are the coefficients of the equation (B-7), and y is the y-axis coordinate on the projection plane.

In the navigation control unit 10, the inclination angle β in the vehicle direction is obtained from the detection signal of the gyro sensor. At this time, the two-dimensional map data is referred to. X (θ + β) is obtained by applying the inclination angle β and the stored coefficients A and B to the equation (B-7). Further, regardless of the magnitude of the inclination, the y coordinate is used without any modification. After obtaining all drawing points (x (θ + β), y 2), by connecting the drawing points, a corrected white line image is obtained.

"Correction of Both Lateral Displacement and Inclination" During actual traveling, both lateral displacement of the vehicle with respect to the lane and inclination in the vehicle direction occur at the same time. Therefore, it is preferable to perform both of the two processes of the lateral shift correction and the tilt correction. Specifically, first, as the reference data, the white line shape when the vehicle is facing the lane direction at the center of the lane is read. Then, the correction for the inclination in the vehicle direction is performed, and then the correction for the lateral displacement is performed. As a result, a white line shape that matches the actual situation is obtained.

The white line shape correction processing has been described above. Here, the description has been made mainly on the case of a straight road, but even when the road and the white line are curved, the white line shape can be corrected by coordinate conversion. That is, a process of converting the position and direction of the viewpoint based on the lateral displacement detection value and the inclination detection value may be performed.

According to the present embodiment, the driver can be presented with a road shape that matches the actual situation, regardless of where the vehicle is located in the lateral direction with respect to the lane. That is, the vehicle does not travel at a fixed position in the track, and the traveling position shifts in the lateral direction, and accordingly, the position of the viewpoint shifts. However, even if the viewpoint corresponding to the stored track shape deviates from the actual viewpoint, the above-described conversion processing can display the track shape viewed from the actual viewpoint.

According to this embodiment, even when the direction of the vehicle and the direction of the lane are at any angle,
It is possible to present to the driver a road shape that matches the actual situation. In other words, the traveling direction of the vehicle does not always coincide with the direction of the traveling path, and the traveling direction assumed in the stored traveling path shape may deviate from the actual traveling direction. Even in such a case, it is possible to display the road shape ahead of the vehicle according to the actual situation by the above-described correction processing.

Further, by performing both the correction of the lateral displacement and the inclination, a more appropriate road shape can be displayed.

The above-described correction process also contributes to a reduction in the amount of data in that an appropriate white line shape can be presented without preparing another type of white line shape data for the same point.

In the present embodiment, the drawing point data (A, B, y) is stored in order to perform the correction in the vehicle direction. However, if only the correction of the lateral displacement is performed, the drawing point data (x, y) may be stored.

As described above, in the present embodiment, the white line shape viewed from the driver's viewpoint is stored in advance in association with each point on the road. The process of storing the white line shape in advance is preferably performed, for example, as follows.

The data (original data) in the form of a white line when the road is viewed from directly above is prepared. The original data is data used as a material for the coordinate conversion processing in FIG. 3 described above, and is stored in the map database storage unit 20 in FIG. The original data is read by the navigation control unit 10. The navigation control unit 10 sets a viewpoint and a reference point, performs the coordinate conversion processing of FIG. 3, and obtains a white line shape viewed from a desired viewpoint. As described above, a white line shape is obtained for each point on the map. The obtained white line shape data is stored in the storage device, and configures the driving viewpoint road shape storage unit 24 in FIG. A readable and writable storage device such as a hard disk is provided as a part or the whole of the map database storage unit 20 so as to store the white line shape. When displaying the track shape on the display, the navigation control unit 10 reads out and processes the white line shape from the hard disk or the like.

By the way, the shape of the white line that is actually seen differs greatly depending on the type of vehicle. This is because the angle at which the road surface can be seen, the position of the viewpoint, the elevation angle, and the like differ greatly depending on the vehicle type.
For example, the viewpoint of an RV-based vehicle is significantly higher than that of a sports car. Therefore, it is preferable to change the shape of the white line according to the type of the vehicle, so that the white line to be displayed can be matched with the actually visible white line.

Referring to FIG. 9, the high-accuracy map database holds original data indicating the shape of a white line viewed from directly above. The navigation control unit 10 acquires information on the height of the driver's viewpoint from outside. For example, vehicle type information, vehicle height information, or information on the height of the viewpoint itself is input. This information may be input from an in-vehicle device or the like, or may be input by a user using an input device.
The user may be allowed to select a desired viewpoint height.
Based on the input information, a white line shape corresponding to the viewpoint height of the vehicle and an appropriate projection plane is created. This allows
A map database is created for each model.

A modification of the above process will be described. The high-accuracy map database in FIG. 9 may have a white line shape (for each point) viewed from the height of the reference viewpoint. That is, one white line shape database based on an appropriate viewpoint is prepared in advance. By the navigation control unit 10,
Based on the input viewpoint height information, the reference white line shape data is converted, and a white line shape corresponding to the viewpoint height (and reference point) of the vehicle is generated. What is necessary is just to perform a coordinate conversion process for changing the height of the viewpoint from the reference viewpoint height to the viewpoint height of the corresponding vehicle.

[Generation Timing of White Line Shape Data] It is considered that the process of generating and storing the white line shape from the driving viewpoint in advance is preferably performed at any one of the following three timings.

(1) Parameters for each vehicle (designation of viewpoint and reference point) are set, all data are converted at once, and the converted data is stored. This aspect has the advantage that vehicle-specific data can be used immediately at any time.

(2) When the route to the destination is calculated, white line shape data of a point on the route is converted. Since the vehicle may deviate from the route and proceed to another road, it is preferable that the conversion process of the white line shape be completed not only at the guidance route but also at other peripheral routes at the branch point. For example, the white line shape data in the three directions of the next intersection is corrected in advance so as to match the vehicle type.

(3) The white line shape at the driving viewpoint corresponding to the point data around the own vehicle position is always subjected to conversion processing for vehicle type adaptation. As the vehicle moves, the previous conversion data is discarded, and the conversion process of the white line shape of the new approaching point is performed. According to this aspect, the white line shape can be displayed efficiently and quickly even when the route guidance is not being performed.

When the above (2) is adopted, the road shape can be presented only during route guidance. In (3), the load of the calculation processing of the control unit 10 increases.
Therefore, it is considered that the processing (1) is most preferable.

"Map database recording medium"
The present invention may be applied to aspects other than the above-described road shape display device. For example, the present invention may be realized in the form of a recording medium on which a map database is recorded. The recording medium records the map data described in relation to the driving viewpoint runway shape storage unit 24 in FIG. The recording medium may be any one that can read and write data by any method such as magnetism, electricity, and light. For example, a CD-ROM and a DVD are suitable. The map database may be stored in a recording medium together with other navigation-related programs. Furthermore, the invention may be applied to other aspects, for example, method aspects.

[0085]

As described above, according to the present invention, it is possible to reliably and promptly present a road shape viewed from the driver's viewpoint without being affected by environmental conditions.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device provided with a roadway shape display device of the present invention.

FIG. 2 is a diagram showing runway shape information stored in a driving viewpoint runway shape storage unit of FIG. 1;

FIG. 3 is a diagram illustrating a process of creating runway shape information in FIG. 2 in advance.

FIG. 4 is a diagram illustrating a method for reducing the amount of white line data stored in the driving viewpoint track shape storage unit of FIG. 1;

FIG. 5 is a diagram illustrating a process of correcting a white line shape with respect to a lateral displacement of a vehicle with respect to a lane.

FIG. 6 is a diagram illustrating a process of correcting a white line shape with respect to the inclination of the vehicle direction with respect to the lane direction.

FIG. 7 is a diagram illustrating a process of correcting a white line shape with respect to the inclination of the vehicle direction with respect to the lane direction.

FIG. 8 is a diagram illustrating a process of correcting a white line shape with respect to the inclination of the vehicle direction with respect to the lane direction.

FIG. 9 is a diagram illustrating a white line data generation process adapted to a viewpoint height for each vehicle type.

[Description of Signs] 10 Navigation control unit, 12 GPS device, 14
Gyro sensor, 16 vehicle speed sensor, 18 position detection unit, 20 map database storage unit, 22 two-dimensional map storage unit, 24 driving viewpoint running shape storage unit, 30 input device, 32 display, 34 speaker, 36 head-up display.

Claims (8)

[Claims] 1. A lane shape storage means for associating and storing each of a plurality of points on a road on a map with a driving viewpoint lane shape representing a lane shape ahead viewed from a viewpoint of a vehicle driver at each point, Own-vehicle-position detecting means for detecting the own-vehicle position; display means for displaying the driving-viewpoint running-road shape; and driving-road-view runningway shape corresponding to the own-vehicle position detected by the own-vehicle-position detecting means. And a display processing means for reading from the display means and displaying the information on the display means. 2. The lane shape display device according to claim 1, wherein the lane shape storage means stores the lane shape as the driving viewpoint lane shape at each position when the driver looks forward from the driver's viewpoint at the corresponding position. The display processing means includes means for generating a continuous runway shape based on the set of discrete representative points. Display device. 3. The lane shape display device according to claim 2, wherein the display processing unit selects a driving viewpoint lane shape to be read from the storage unit based on a lane around the own vehicle position or a planned lane. A runway shape display device characterized by the above-mentioned. 4. The lane shape display device according to claim 1, further comprising a lateral deviation detecting unit configured to detect a lateral deviation of the vehicle with respect to the lane, wherein the display processing unit determines the lane based on the lateral deviation. The driving viewpoint road shape read from the shape storage means is
A runway shape display device wherein coordinates are converted into a runway shape viewed from a laterally shifted viewpoint. 5. The roadway shape display device according to claim 1, further comprising: a tilt detection unit configured to detect a tilt in a vehicle direction with respect to a roadway direction, wherein the display processing unit performs: A running road shape display device, wherein the running road shape read from the running shape storage means is coordinate-converted into a running road shape viewed from an inclined viewpoint. 6. The roadway shape display device according to claim 1, wherein the display means is a head-up display for displaying an image on a windshield of the vehicle. . 7. The lane shape display device according to claim 1, wherein the driving viewpoint lane shape is data indicating a shape of a line representing a lane drawn on the lane. Running road shape display device. 8. A map database of roads is recorded. In the map database, each of a plurality of points on the road and a driving viewpoint lane representing the shape of the front lane at each point viewed from the viewpoint of the vehicle driver. A map database recording medium characterized by being associated with a shape.