The present invention relates to a driving support apparatus, driving support method, and program, and more particularly to a driving support apparatus and driving support method that provide a driver with information relating to the traveling position of a vehicle, and provide support so as to enable traveling in an appropriate position.
In Patent Literature 1, a lane keeping support apparatus is disclosed that gives notification by changing the color of an image when a vehicle departs from a lane in which it is currently traveling or there is a possibility of such departure. The lane keeping support apparatus described in Patent Literature 1 displays an image indicating a vehicle and an image indicating left and right lane boundary lines on a display screen, offsets the image indicating the vehicle within the display screen according to the departure direction, provides blinking display of a lane boundary line in the departure direction, and gives notification by changing the color of an image indicating the vehicle according to the speed of travel in the departure direction.
In Patent Literature 2, a lane keeping support apparatus is disclosed that displays the situation around a traveling vehicle. The lane keeping support apparatus described in Patent Literature 2 identifies a lane in which a vehicle is traveling and also determines whether the vehicle is straddling lanes, and corrects the display position of a vehicle mark so that the vehicle also straddles lanes on the display screen if the vehicle is straddling lanes, or so that the vehicle does not straddle lanes on the display screen if the vehicle is not straddling lanes.
However, with the lane keeping support apparatus described in Patent Literature 1, notification is not given of a case in which a vehicle is traveling while deviating in a certain direction but not to the extent of departing from a lane, and it is difficult to support ascertainment of a vehicle's traveling position within a lane. In particular, a problem for a driver who does not have a feel for the width of the vehicle, such as an inexperienced driver, is the difficulty of judging what degree of evasion is appropriate in order to avoid contact with an oncoming vehicle or a vehicle parked at the side of the road.
Also, with the lane keeping support apparatus described in Patent Literature 2, although it is possible to ascertain whether a vehicle is traveling within a lane or is straddling lanes, it is still difficult to support a driver in a situation in which it is necessary to ascertain a vehicle's traveling position within a lane, such as when the vehicle is traveling while deviating in a certain direction but not to the extent of departing from a lane.
It is an object of the present invention to provide a driving support apparatus, driving support method, and program that enable a driver's judgment to be facilitated by making it possible to easily confirm the traveling position of a vehicle within a lane.
A driving support apparatus of the present invention employs a configuration having: an imaging section that images the surroundings of a vehicle; a lane detection section that detects the left and right edges of a traveling lane in which the vehicle is traveling from a captured image; a vehicle position calculation section that calculates a displacement direction and displacement amount of the vehicle in the lane width direction with respect to the center of the traveling lane; a display image generation section that generates a display image in which, in a lane image that includes lane boundary markers indicating the left and right edges of the traveling lane and a lane center marker indicating the center of the traveling lane, the center position of the vehicle image is superimposed displaced in the lane width direction from the position of the lane center marker in accordance with the displacement direction and displacement amount calculated by the vehicle position calculation section; and a display section that outputs the display image.
A driving support method has: a step of imaging the surroundings of a vehicle; a step of detecting the left and right edges of a traveling lane in which the vehicle is traveling from a captured image; a step of calculating a displacement direction and displacement amount of the vehicle in the lane width direction with respect to the center of the traveling lane; a display image generation step of generating a display image in which, in a lane image that includes lane boundary markers indicating the left and right edges of the traveling lane and a lane center marker indicating the center of the traveling lane, the center position of the vehicle image is superimposed displaced in the lane width direction from the position of the lane center marker in accordance with the displacement direction and displacement amount calculated by the calculation step; and a step of outputting a generated display image.
From another viewpoint, the present invention is a program that causes a computer to execute each step of the above-described driving support method.
The present invention makes it possible to easily confirm the traveling position of a vehicle within a lane, thereby facilitating the judgment of a driver who does not have an adequate feel for the width of the vehicle, such as an inexperienced driver, as to whether there is sufficient margin of width to avoid an oncoming vehicle or a vehicle parked at the side of the road.
Now, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
As shown in
Imaging section 110 is a visible light or infrared light stereo camera that is positioned so as to image an area that includes at least the road surface of a lane in which a vehicle is traveling ahead of the vehicle, and that transfers a captured image to lane detection section 120. A CCD (Charge Coupled Device), CMOS (Complementary Metal Oxide Semiconductor), or suchlike image sensor is mainly used as an imaging method. When a wide-angle lens is used, in particular, distortion may occur in a captured image. Imaging section 110 also performs correction of such distortion.
Lane detection section 120 detects the left and right edges of a lane in which a vehicle is traveling (hereinafter referred to as “traveling lane”) from a captured image. A lane includes one or a plurality of lanes. The left and right edges of a traveling lane may be a white line, side wall, or the like, and are detected using a known image recognition algorithm.
Vehicle position calculation section 130 calculates a displacement direction and displacement amount of a vehicle in the lane width direction with respect to the center of the traveling lane, based on a position in a captured image of the left and right edges of the traveling lane detected by lane detection section 120.
Display image generation section 140 generates a lane image that includes lane boundary markers indicating the left and right edges of the traveling lane and a lane center marker indicating the center of the traveling lane. Then display image generation section 140 generates a display image in which a vehicle image is positioned in the lane image with the center of the vehicle displaced according to the displacement direction and displacement amount in the lane width direction with respect to the center of the traveling lane of the vehicle calculated by vehicle position calculation section 130.
Display section 150 is a display that displays a composite image in front of the driver within the passenger compartment of a vehicle, and displays an image generated by display image generation section 140. Display section 150 is installed in a position in which it does not obstruct the driver's forward field of view. As for type, the display may be a liquid crystal display, an organic EL (Organic Electro-Luminescence) or suchlike light emitting display, a fluorescent tube display, a laser display, or an HUD (Head-Up Display) combining an optical system and combiner (a screen displaying a virtual and real image at the same distance) with any of these. A head-up display is installed so that an image is displayed on the windshield, for example.
The operation of lane keeping support apparatus 100 configured as described above will now be explained.
Using
First, vehicle position calculation section 130 finds center line 210 in captured image 200 indicating the center of the vehicle in the width direction from the camera installation position and direction as shown in
Next, vehicle position calculation section 130 finds the coordinates of points 240, 250, and 260 at identical vertical-direction positions on center line 210, and left boundary line 220 and right boundary line 230 of the traveling lane detected by lane detection section 120.
Then vehicle position calculation section 130 finds length D1 between point 240 on center line 210 and point 250 on left boundary line 220 of the traveling lane, and length D2 between point 240 on center line 210 and point 260 on right boundary line 230 of the traveling lane.
The displacement direction is left when D1<D2, no-displacement when D1=D2, and right when D2>D1, and the displacement amount is found as a proportional value calculated as |S2−S1|/2(S1+S2).
Display image generation section 140 generates lane image 300 that includes lane boundary markers 310 representing the left boundary line and right boundary line of the traveling lane, and lane center marker 320 indicating the center of the traveling lane, shown in
If there are a plurality of lanes, a lane image such as shown in
Next, display image generation section 140 generates a display image in which vehicle image 330 representing the vehicle is superimposed on lane image 300, as shown in
At this time, vehicle image 330 is positioned horizontally displaced by length L leftward from lane center marker 320. Here, the displacement direction is calculated by vehicle position calculation section 130 (
In an example of conventional technology, for instance, no notification is given in cases such as those in
As described in detail above, lane keeping support apparatus 100 of the present embodiment is provided with lane detection section 120 that detects the left and right edges of a traveling lane in which a vehicle is traveling from a captured image, vehicle position calculation section 130 that calculates a displacement direction and displacement amount of the vehicle in the lane width direction with respect to the center of the lane in which the vehicle is traveling, and display image generation section 140 that generates a display image in which, in a lane image that includes lane boundary markers 310 indicating the left and right edges of a lane and lane center marker 320 indicating the center of the traveling lane, vehicle image 330 is superimposed with its center displaced in the lane width direction from the lane center marker 320 position in accordance with the displacement direction and displacement amount calculated by vehicle position calculation section 130.
As shown in
Also, in the present embodiment, displaying a display image on the windshield by means of a head-up display enables the driver to confirm the view ahead while simultaneously viewing the display image, and to grasp the position of the vehicle and the view ahead in an associated fashion, enabling the driver to get a better feel for the width of the vehicle.
Embodiment 2 is an example in which an appropriate speed marker is also displayed.
As shown in
Appropriate speed calculation section 160 calculates appropriate speed Vr based on speed limit information relating to the road being traveled and the road environment. For example, appropriate speed calculation section 160 calculates a maximum legal speed from information on the type of road being traveled acquired from car navigation apparatus 510 or the like, and sets a value obtained by multiplying the maximum legal speed by a predetermined factor (for example, 0.8) as appropriate speed Vr.
If appropriate speed calculation section 160 recognizes a road sign or road marking specifying a maximum speed from an image captured by imaging section 110, appropriate speed calculation section 160 takes a value obtained by multiplying the recognized specified maximum speed by a predetermined factor (for example, 0.8) as appropriate speed Vr. Also, if, as a road environment, appropriate speed calculation section 160 detects a curve ahead by means of a method such as recognizing a road sign or road marking indicating a curve in a captured image, or detects a wet or icy road surface by means of a raindrop sensor, reflection of the road surface in a captured image, or the like, appropriate speed calculation section 160 may lower appropriate speed Vr.
Vehicle speed calculation section 170 compares vehicle speed Vo acquired from speed sensor 520 or the like and appropriate speed Vr calculated by appropriate speed calculation section 160, and calculates Vo−Vr, the relative speed of the vehicle with respect to the appropriate speed.
Display image generation section 141 generates a lane image comprising a lane center marker indicating the center of the traveling lane, and an appropriate speed marker positioned so as to be perpendicular to lane boundary markers indicating the left and right edges of the traveling lane or the lane center marker. Then display image generation section 141 generates a display image in which a vehicle image is positioned in the lane image with the center of the vehicle displaced according to the displacement direction and displacement amount in the lane width direction with respect to the center of the traveling lane of the vehicle calculated by vehicle position calculation section 130, and displaced in a front-back direction of the lane from the appropriate speed marker 610 (
Thus, according to the present embodiment, lane keeping support apparatus 500 is provided with appropriate speed calculation section 160 that calculates an appropriate speed using speed limit information relating to the road a vehicle is traveling, and vehicle speed calculation section 170 that calculates the relative speed of the vehicle with respect to the appropriate speed calculated by appropriate speed calculation section 160. Display image generation section 141 displays a display image in which a vehicle image is positioned in the lane image with the center of the vehicle displaced according to the relative speed of the vehicle with respect to the appropriate speed in addition to the displacement direction and displacement amount in the lane width direction with respect to the center of the traveling lane, producing an effect of enabling the driver to see at a glance the traveling position and speed of the vehicle within the lane, and to control the traveling position while also adjusting the speed when operating on a curve or the like, thereby facilitating lane keeping.
In the present embodiment, appropriate speed calculation section 160 and vehicle speed calculation section 170 are combined with lane keeping support apparatus 100 in
Embodiment 3 is an example in which a position at which an obstacle is avoided is also displayed.
As shown in
In the event of detecting an obstacle such as a bicycle traveling in the vicinity of the traveling lane, or a stationary vehicle or oncoming vehicle protruding into the traveling lane, forward obstacle detection section 180 notifies display image generation section 142 of the position of the obstacle in the lane width direction. Forward obstacle detection section 180 detects an obstacle or the like outside the vehicle based on an image captured by an extra-vehicle imaging camera and extra-vehicle radar output, for example.
Display image generation section 142 generates a lane image comprising a lane center marker indicating the center of the traveling lane and lane boundary markers indicating the left and right edges of the traveling lane. Then display image generation section 142 generates a display image in which recommended traveling position marker 810 (
Thus, according to the present embodiment, lane keeping support apparatus 700 is provided with forward obstacle detection section 180 that detects an obstacle such as a bicycle traveling in the vicinity of the traveling lane, or a stationary vehicle or oncoming vehicle protruding into the traveling lane, and display image generation section 142 generates a display image that indicates a recommended traveling position according to a situation ahead in addition to and combined with a vehicle's traveling position. By this means, a driver can see at a glance in what position the vehicle should travel in order to avoid an obstacle, and can easily travel with this reflected in the operation of the vehicle.
Here, by making recommended traveling position marker 810 and vehicle image 330 the same shape, displacement can be grasped through the nature of overlapping between vehicle image 330 and recommended traveling position marker 810, enabling the support effect to be heightened. At this time, color or texture may also be changed to enable the driver to distinguish between recommended traveling position marker 810 and vehicle image 330.
Embodiment 4 is an example in which display is performed that makes it possible to grasp an actual situation more correctly.
As shown in
Lane width calculation section 910 calculates the lane width of a traveling lane created by left and right lane boundaries in an image detected by lane detection section 120. Specifically, lane width calculation section 910 finds a three-dimensional position in a camera coordinate system using parallax for two points that are vertically identical positions on a left boundary line and right boundary line in a stereo image acquired by imaging section 110. The difference between the two points calculated by lane width calculation section 910 is the lane width of the traveling lane.
Storage section 920 stores vehicle width information and vehicle image vehicle width information.
Display image generation section 930 generates a lane image in accordance with the lane width, and then generates a display image by positioning the vehicle image.
The actual display image generation method used by display image generation section 930 will now be described.
Display image generation section 930 first calculates the display width of lane boundary markers indicating the left and right edges of the traveling lane. When the vehicle width of a vehicle image stored in storage section 920 is designated CG [Pix], the actual vehicle width of the vehicle is designated Cw [m], and the vehicle width calculated by lane width calculation section 910 is designated Lw [m], width LG [Pix] of the lane boundary markers that are part of a vehicle image is calculated by means of the following equation.
LG=Lw·CG/Cw
Next, a lane center marker indicating the center of the traveling lane is positioned midway between the lane boundary markers. Furthermore, a vehicle image is generated by positioning an appropriate speed marker so as to be perpendicular to these lane boundary markers or the lane center marker.
Then display image generation section 930 generates a display image in which a vehicle image is positioned in the lane image with the center of the vehicle displaced according to a displacement direction and displacement amount in the lane width direction with respect to the center of the traveling lane of the vehicle calculated by vehicle position calculation section 130, and displaced in a front-back direction of the lane from an appropriate speed marker 610 (
By generating a display image in this way, the actual positional relationship between a vehicle and lane can be represented more correctly in the display image.
For example, when a vehicle is traveling on a comparatively wide road such as shown in
Thus, according to the present embodiment, lane keeping support apparatus 900 is provided with lane width calculation section 910 that calculates a lane width, and storage section 920 that stores a lane boundary marker width standard value, vehicle image vehicle width, and actual vehicle width information. Display image generation section 930 displays a display image in which a vehicle image is positioned in a lane image displaced according to the relative speed of the vehicle with respect to an appropriate speed in addition to a displacement direction and displacement amount in the lane width direction with respect to the center of the traveling lane. In addition to this, display image generation section 930 adjusts the display width of lane boundary markers when a display image is generated. By this means, an effect is produced of enabling the driver to grasp the traveling position and speed of the vehicle within a lane more correctly, and to control the traveling position while also adjusting the speed, thereby facilitating lane keeping.
In the present embodiment, the vehicle image width is fixed and the lane boundary width is adjusted, but the lane boundary width may be fixed and the vehicle image width adjusted.
In the present embodiment, lane width calculation section 910 and storage section 920 are combined with lane keeping support apparatus 500 in
In the present embodiment, forward obstacle detection section 180 of lane keeping support apparatus 700 in
The above description presents examples of preferred embodiments of the present invention, but the scope of the present invention is not limited to these.
For example, in the above embodiments it is also possible to perform presentation in combination with another information presentation means, such as sound, speech information, or vibration, for example. Combined use of a meter display is also possible.
In the above embodiments, the terms “driving support apparatus” and “driving support method” have been used, but this is simply for convenience of description, and a term such as “lane keeping support apparatus” may also be used for an apparatus, and a term such as “vehicle information display method” for a method.
Details of configuration sections composing an above-described driving support apparatus, such as the type of a lane detection section and the superimposed image generation method of a display image generation section, for example, are not limited to those in the above embodiments.
An above-described driving support method is implemented by a program for causing this driving support method to function. This program is stored in a computer-readable recording medium.
The disclosure of Japanese Patent Application No. 2009-169119, filed on Jul. 17, 2009, including the specification, drawings and abstract, is incorporated herein by reference in its entirety.
A driving support apparatus and driving support method according to the present invention alleviate driver anxiety by being installed in a vehicle, and are suitable for use as a driving support system that supports safe driving. They can also be applied to a use such as improving a driver's driving technique.
Number | Date | Country | Kind |
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2009-169119 | Jul 2009 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2010/002980 | 4/26/2010 | WO | 00 | 1/13/2012 |