JP7149154B2 - Driving support device - Google Patents

Description

The present invention relates to a driving assistance device that assists driving of a vehicle.

BACKGROUND ART A driving assistance device described in Patent Document 1 is known for assisting driving of a vehicle. This driving support device calculates a target speed according to the speed limit of the road on which the vehicle is traveling and the road structure, and informs the driver that it is necessary to decelerate the vehicle based on the vehicle speed and the calculated target speed. Driving assistance that gives notification (warning) is being executed.

Japanese Patent No. 5587170

Here, for example, when the outside of the vehicle is dark, such as at night, in a tunnel, or during bad weather, or when there is a relatively large amount of rainfall, there is a risk of poor visibility for the driver. In addition, for example, when a relatively strong crosswind is blowing or when the road surface is rough, the steering wheel may be lost. However, the driving support device described in Patent Document 1 does not consider the above-described situations, and calculates a target speed that is the same as during normal operation even when the vehicle is running under these conditions. Driving support is performed according to the situation. As a result, there is a risk that it will not be possible to provide driving assistance according to the surrounding conditions, such as being unable to encourage the driver to drive more cautiously in situations where visibility may be poor or the steering wheel may be taken.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a driving assistance device capable of performing driving assistance according to the surrounding conditions of the vehicle.

Therefore, the driving support device
an acquisition unit that acquires road information including the speed limit and road width of the road on which the vehicle is traveling;
a setting unit that sets a target speed based on road information and vehicle width;
a correction unit that corrects the set target speed according to the surrounding conditions of the vehicle;
a support unit that executes driving support for notifying a driver that the vehicle needs to be decelerated based on the corrected target speed and vehicle speed. Here, the surrounding situation is at least a situation in which the steering wheel can be taken, out of the situation in which visibility may be poor and the situation in which the steering wheel may be taken.

According to the driving assistance device, it is possible to perform driving assistance according to the surrounding conditions of the vehicle.

1 is a system configuration diagram showing an example of a driving support system; FIG. FIG. 2 is a block diagram showing an example of functions of the driving support device; FIG. FIG. 5 is a diagram for explaining an example of target speed setting; 4 is a flowchart showing an example of driving assistance processing executed by the driving assistance device; FIG. 10 is a diagram for explaining setting of a correction value using an output of an illuminance sensor; FIG. FIG. 5 is a diagram for explaining setting of correction values using the output of a raindrop sensor; FIG. 4 is a diagram for explaining setting of a correction value using an output of a vehicle height sensor; FIG. FIG. 4 is a diagram for explaining setting of a correction value using an output of a vehicle height sensor; FIG. FIG. 10 is a diagram for explaining another example of target speed setting; FIG. 10 is a diagram showing an example of a table that defines the relationship between the road structure and road width correction width based on road attachments for each speed limit; FIG. 10 is a diagram for explaining another example of target speed setting; FIG. 11 is a block diagram showing a modification of the functions of the driving support device; It is a figure for demonstrating the setting of the target speed using the output of an illuminance sensor. FIG. 10 is a diagram for explaining setting of a target speed using an output of a raindrop sensor; FIG. FIG. 4 is a diagram for explaining setting of a target speed using an output of a vehicle height sensor; FIG. FIG. 4 is a diagram for explaining setting of a target speed using an output of a vehicle height sensor; FIG.

Embodiments for carrying out the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a system configuration diagram showing an example of a driving support system mounted on a vehicle.

The driving assistance system 1 includes a GPS receiver 10 , a map database 20 , a vehicle speed sensor 30 , a surrounding condition detector 40 , an alarm device 50 and a driving assistance device 100 .

The GPS receiver 10, the map database 20, the vehicle speed sensor 30, the ambient condition detector 40, and the notification device 50 are communicably connected to the driving support device 100 via a CAN (Controller Area Network). However, the network is not limited to this, and a network such as FlexRay (registered trademark) or MOST (Media Oriented System Transport) (registered trademark) may be used instead of CAN.

The map database 20 is built, for example, in an HDD (Hard Disk Drive) or SSD (Solid State Drive) mounted on a vehicle, and stores map information associated with latitude and longitude. More specifically, the map information includes the road type indicating whether it is a general road or an expressway, and the road shape including the curvature of the curve, the slope, the shape of the intersection, the branch point, the number of lanes, and the width of the lane. In addition to this information, it includes information such as center lines such as median strips, pedestrian crossings, sidewalks, stop lines and traffic signal placement information, as well as information such as speed limits on each road and buildings adjacent to each road. . In addition, the map information includes location information and shape information of road accessories such as utility poles, signs, street lights, billboards, post boxes, curbs, and guardrails, which are provided on the side of the road such as roadside strips and road shoulders. good too. Note that the map information may be acquired from, for example, an external map information data center or the like via a communication device (not shown), so that the latest map information can be updated.

The ambient condition detector 40 is for detecting the current ambient condition of the vehicle including at least one of the brightness outside the vehicle, the rainfall condition, the crosswind environment and the smoothness of the road surface, as will be described later in detail. Therefore, the ambient condition detector 40 includes at least one of an illuminance sensor 40A, a raindrop sensor 40B and a vehicle height sensor 40C.

The illuminance sensor 40A is attached, for example, to the interior side of the front windshield of the vehicle, and detects the brightness (illuminance) outside the vehicle. Such an illuminance sensor 40A is provided, for example, for an auto light system that automatically turns on lights such as headlights of a vehicle when the illuminance outside the vehicle falls below a threshold value for determining auto lights. There may be.

The raindrop sensor 40B is attached, for example, to the interior side of the front windshield of the vehicle, and detects the amount of raindrops adhering to the surface of the front windshield. More specifically, the raindrop sensor 40B includes, for example, an irradiation unit that irradiates light such as infrared rays toward the front windshield and a light reception unit that receives infrared rays reflected from the front windshield. The amount of raindrops adhering to the surface of the front windshield is detected according to the increase or decrease in amount. Such a raindrop sensor 40B is provided, for example, for an autowiper system that changes the wiping interval of the windshield wipers depending on whether the amount of raindrops is equal to or greater than the threshold value for autowiper determination. may

The vehicle height sensor 40C detects the vehicle height. More specifically, the vehicle height sensor 40C is provided, for example, for each of the left and right wheels on the front side or the rear side, and detects the vehicle height from the relative displacement between the vehicle body and a movable portion (suspension arm) including the left and right wheels and the vehicle body. A suspension stroke sensor may be mentioned. Such a vehicle height sensor 40C is provided, for example, for an auto-leveling system that automatically adjusts the optical axis of the headlight based on its output, or for attitude control of the shock absorbers of each wheel. There may be.

The notification device 50 is for notifying the driver that it is necessary to perform a predetermined driving. Such a notification device 50 includes, for example, an actuator 50A that is driven in accordance with a command signal from the driving support device 100 and generates a force (reaction force) against depression of an accelerator pedal (not shown), and A speaker 50</b>B that is provided and generates a predetermined warning sound in response to a command signal from the driving support device 100 can be used.

In addition to the warning sound through the speaker 50B, for example, by changing the display color of the display screen provided in the dashboard or the car navigation system according to the command signal from the driving support device 100, It may be notified that it is necessary to perform a predetermined operation.

The driving support device 100 includes a CPU (Central Processing Unit) 100A that is a processing device that executes various control programs, a flash ROM (Read Only Memory) 100B that stores control programs and the like and can store various data, It has a RAM (Random Access Memory) 100C that serves as a temporary storage area, a communication circuit 100D that is a CAN transceiver for connecting to a network such as CAN, and a bus 100E that interconnects them.

The CPU 100A of the driving support device 100 can input signals from the GPS receiver 10, the vehicle speed sensor 30, and the ambient condition detector 40 via the communication circuit 100D, and can read map information from the map database 20. It has become. The CPU 100A also reads out and executes a control program stored in the flash ROM 100B, thereby executing driving support processing using these input signals. Functions of the driving support device 100 for executing the driving support process will be described below.

The driving support device 100 includes a road information acquisition unit 102, a target speed setting unit 104, a target speed correction unit 106, and a driving support unit 108, as shown in FIG.

A road information acquisition unit (hereinafter simply referred to as “acquisition unit”) 102 receives a signal from a GPS receiver 10 that receives a signal transmitted by a GPS satellite, and processes this signal to obtain the current position of the vehicle (for example, , latitude and longitude of the vehicle). Then, the acquiring unit 102 acquires road information at a predetermined distance (for example, 50 m) in front of the vehicle according to the current position of the vehicle and the map information by reading the map information from the map database 20 .

A target speed setting unit (hereinafter simply referred to as a “setting unit”) 104 sets a target speed based on the speed limit and road width of the road (traveling road) on which the vehicle is traveling, and the vehicle width, among the acquired road information. Set speed. More specifically, the setting unit 104 first determines whether the value obtained by subtracting the vehicle width from the road width (the difference between the road width and the vehicle width) is less than a predetermined value (for example, 2.0 m). . When the road width is narrow (the difference between the road width and the vehicle width is less than a predetermined value), it is not appropriate for safety to maintain the vehicle speed exceeding the speed limit. Therefore, it is desirable to decelerate the vehicle as the difference between the road width and the vehicle width becomes smaller. Therefore, the target speed is set so that the smaller the difference between the road width and the vehicle width, the smaller the target speed, with the regulated speed as the upper limit. For this reason, the flash ROM 100B may store a table indicating the relationship between the difference between the road width and the vehicle width and the target speed, which is predetermined for each speed limit.

FIG. 3 shows an example of a target speed set based on the speed limit of 60 km/h, road width and vehicle width Wv on a one-lane road with a speed limit of 60 km/h. As shown in FIG. 3, when there are white lines, center lines, etc., the road width included in the map information of the map database 20 may be stored as the distance between the white lines and the center line, for example. . In this example, the difference between the road width Wr1 and the vehicle width Wv at a predetermined distance (0 m to 50 m in the traveling direction from the vehicle) is less than the predetermined value, and the target speed is set to a value slightly smaller than the regulated speed. The predetermined value to be compared with the difference between the road width and the vehicle width is not limited to the value described above, and may be determined according to the type of vehicle (especially, vehicle width) and general road width at the time of design. It may be set to an appropriate value.

A target speed correction unit (hereinafter simply referred to as a “correction unit”) 106 corrects the target speed set by the setting unit 104 based on the current surrounding conditions of the vehicle. More specifically, as will be described later in detail, the correction unit 106 first uses the output of the surrounding condition detector 40 to determine whether the current surrounding condition of the vehicle is a condition that may result in poor visibility as described above. or whether the situation is such that the above-mentioned handle can be taken. Then, the correction unit 106 sets a correction value (including the case where the correction value=0) for correcting the set target speed according to the determination result, and corrects the target speed with this correction value.

A driving assistance unit (hereinafter simply referred to as “assistance unit”) 108 executes driving assistance to assist the driving of the vehicle based on the vehicle speed acquired from the vehicle speed sensor 30 and the target speed corrected by the correction unit 106 . If the current vehicle speed exceeds the corrected target speed, it is not appropriate to maintain the current vehicle speed for safety reasons. Therefore, in order to execute driving assistance that encourages the driver to drive at a reduced vehicle speed, the assistance unit 108 first compares the acquired vehicle speed with the corrected target speed, for example, and sets the driving assistance level. do.

For example, when the vehicle speed exceeds the corrected target speed, the driving assistance level is set according to the degree. More specifically, the driving assistance levels are set to levels 1, 2, and 3, for example, as the difference between the vehicle speed and the corrected target speed increases. Further, the driving assistance level is set to 0 when the vehicle speed is equal to or less than the corrected target speed.

After setting the driving support level, the support unit 108 outputs a command signal corresponding to the driving support level to at least one of the notification device 50, that is, the actuator 50A and the speaker 50B (and the display screen). Then, the driver is notified (warned) that the vehicle needs to be decelerated to achieve the corrected target speed via the reaction force generated in the accelerator pedal by driving the actuator 50A and the warning sound from the speaker 50B. Driving assistance is executed.

As the driving assistance by the warning, for example, depending on the driving assistance level, the strength of the reaction force generated in the accelerator pedal is changed, or a different warning sound is emitted from the speaker 50B (and the color tone of the display screen is changed accordingly). to do. When the driving support level is 0, no command signal is output to the notification device 50 because there is no need to execute driving support.

Driving assistance processing executed by the driving assistance device 100 having the functions described above will be described below with reference to FIG. 4 .
FIG. 4 is a flowchart showing an example of driving support processing. It should be noted that the driving support process is executed at predetermined intervals when the ignition switch is turned on.

At step 10, the CPU 100A processes the signal from the GPS receiver 10 to detect the current position of the vehicle, and uses the map information in the map database 20 to acquire road information at a predetermined distance (eg, 50 m) in front of the vehicle. .

In step 12, the CPU 100A obtains a predetermined value obtained by subtracting the vehicle width Wv from the road width W _X1-X2 at a predetermined distance in front of the vehicle (the road width W _0-50 at a distance of 0 m to 50 m in the traveling direction in the example shown in FIG. 3). Determine if it is less than the value. When CPU 100A determines that the difference between road width W _X1 -X2 and vehicle width Wr is less than a predetermined value (W _X1 -X2 -Wv<predetermined value), the process proceeds to step .

In step 14, the CPU 100A refers to a table showing the relationship between the value obtained by subtracting the vehicle width from the road width and the target speed, which is determined for each speed limit described above, or obtains the target speed using a predetermined function. A target speed corresponding to the regulated speed and W _X1 -X2 -Wv is set.

At step 16, the CPU 100A corrects the target speed set at step 14 based on the current surrounding conditions of the vehicle. Correction of the target speed will be described below with reference to FIGS. 5 to 8. FIG.

The CPU 100A first determines the presence or absence of the illuminance sensor 40A, the raindrop sensor 40B, and the vehicle height sensor 40C, that is, whether or not these sensors 40A to 40C are provided in the vehicle. The presence or absence of each sensor 40A-40C is determined by a known method such as checking the data indicating the presence or absence of each sensor 40A-40C included in the vehicle specification information stored in the flash ROM 100B.

When the illuminance sensor 40A is provided in the vehicle, the CPU 100A determines whether the illuminance is equal to or less than the first threshold a for illuminance determination based on the output of the illuminance sensor 40A. The first threshold value a may be the same value as the threshold value for automatic light determination described above, or may be set separately from this threshold value.

When the CPU 100A determines that the illuminance is equal to or less than the first threshold a, it sets a correction value. In this case, the current surroundings of the vehicle are assumed to be such that the outside of the vehicle is dark, such as at night, in a tunnel or in bad weather, which can lead to poor visibility for the driver.

For setting the correction value when the outside of the vehicle is dark, the flash ROM 100B stores, for example, as shown in FIG. A proportional function or a predetermined function indicating the relationship with the correction value that fluctuates to a constant value, or a correction value that is constant regardless of the illuminance on the condition that the illuminance is equal to or lower than the first threshold a is stored.

Therefore, when the CPU 100A determines that the illuminance is equal to or less than the first threshold a, it sets the correction value based on the relationship shown in FIG. In order to reduce the calculation load, the correction value corresponding to the output (illuminance) of the illuminance sensor 40A is calculated from the relationship shown in FIG. You may choose. For example, if the illuminance exceeds the first threshold a, 0 is selected as the correction value.

When the raindrop sensor 40B is provided in the vehicle, the CPU 100A determines whether or not the amount of raindrops is greater than or equal to the second threshold b for determining the amount of raindrops based on the output of the raindrop sensor 40B. The second threshold value b may be the same as the threshold value for auto wiper determination, or may be set separately from this threshold value.

When the CPU 100A determines that the amount of raindrops is equal to or greater than the second threshold b, it sets a correction value. In this case, the current surroundings of the vehicle are assumed to be, for example, relatively heavy rainfall, which can lead to poor visibility for the driver.

In order to set the correction value when the amount of rainfall is large, the flash ROM 100B stores, for example, as shown in FIG. A proportional function or a predetermined function that indicates the relationship with the correction value that fluctuates, or a correction value that is a constant value regardless of the amount of raindrops on the condition that the amount of raindrops is equal to or greater than the second threshold value b is stored. .

Therefore, when the CPU 100A determines that the amount of raindrops is equal to or greater than the second threshold value b, the CPU 100A sets the correction value based on the relationship shown in FIG. In order to reduce the computational load, instead of causing the CPU 100A to execute the process of comparing the amount of raindrops and the second threshold value b, correction corresponding to the output (amount of raindrops) of the raindrop sensor 40B from the relationship shown in FIG. You can choose a value. For example, if the amount of raindrops is less than the second threshold b, 0 is selected as the correction value.

When the vehicle is provided with the vehicle height sensor 40C, the CPU 100A first calculates the vehicle height difference between the left and right front or rear sides of the vehicle based on the output of each of the left and right vehicle height sensors 40C on the front or rear side of the vehicle. (Inclination (roll angle) in the lateral direction of the vehicle body) is calculated. Next, the CPU 100A determines whether or not the calculated vehicle height difference between the left and right sides is equal to or greater than a third threshold value c for determining inclination in a predetermined cycle T (for example, several seconds (sec)). Note that the vehicle height sensor 40C may be provided on both the front and rear sides of the vehicle. may be compared with a third threshold c.

When the CPU 100A determines that the vehicle height difference between the left and right sides is greater than or equal to the third threshold value c, it determines whether the first state in which the vehicle height difference between the left and right sides is greater than or equal to the third threshold value c has continued for a predetermined period of time. determine whether or not When the CPU 100A determines that the first state has continued for a predetermined period of time in the predetermined period T, the CPU 100A sets a correction value.

When the first state continues for a predetermined period of time in the predetermined cycle T, the vehicle body is tilted to one side for a predetermined period of time. is considered to be in a situation where In such a situation, the driver is required to drive more carefully due to the relationship between the vehicle speed and the wind speed. That is, in situations where crosswind wind speeds are relatively high, there is a high possibility that the steering wheel will be pulled.

In order to set the correction value when it is determined that the first state continues for a predetermined period of time in the predetermined period T, the flash ROM 100B stores a predetermined duration of the first state, for example, as shown in FIG. A proportional function or a predetermined function that indicates the relationship between the duration time and the correction value that fluctuates so that it increases as the duration time is greater than or equal to the duration time, or the duration time on the condition that the first state has continued for a predetermined time A correction value that is a constant value may be stored regardless.

Therefore, when the CPU 100A determines that the first state, that is, the state in which the vehicle height difference between the left and right sides is equal to or greater than the third threshold value c has continued for a predetermined period of time in the predetermined cycle T, the CPU 100A determines the correction value based on the relationship shown in FIG. set. In order to reduce the computational load, the CPU 100A does not execute the process of determining whether the first state has continued for a predetermined period of time. A correction value may be selected that corresponds to the duration of the first state. For example, if the first state has not continued for a predetermined time, 0 is selected as the correction value.

Note that FIG. 7 shows an example where, in the predetermined period T, duration t1 of the first state<predetermined time<duration t2 of the first state. For example, when a variation value is stored in the flash ROM 100B as a correction value, a correction value corresponding to the duration t2 is set.

Further, the crosswind environment detection is not limited to using only the outputs of the left and right vehicle height sensors 40C. For example, if the vehicle is provided with a steering angle sensor that detects the angle of the steering wheel (steering angle), the outputs of the steering angle sensors may be used in addition to the outputs of the left and right vehicle height sensors 40C. For example, when the vehicle is traveling on a curve or turning, such as when turning right or left, the vehicle body tilts and the vehicle height difference between the left and right sides becomes large. Therefore, even if the CPU 100A determines that the vehicle height difference between the left and right sides exceeds the third threshold value c, if it determines that the steering angle is equal to or greater than a predetermined value based on the output of the steering angle sensor, the left and right vehicle height difference The correction value may be set to 0, assuming that the change in height difference is due to the driver's will. On the other hand, when the vehicle height difference between the left and right sides exceeds the third threshold value c and the steering angle is less than the predetermined value, it may be considered that the change in the vehicle height difference between the left and right sides is due to the crosswind.

Furthermore, in general, when the steering wheel is operated by the will of the driver, the tires are angled after the steering wheel is operated, and the vehicle starts to turn. Therefore, the rise of the output of the steering angle sensor is earlier than the rise of the output of the vehicle height sensor 40C. On the other hand, in a situation where a relatively strong crosswind is blowing, the steering wheel is taken after the vehicle moves, so the rise of the output of the vehicle height sensor 40C is earlier than the rise of the output of the steering angle sensor. Therefore, by comparing the rise of the output of the steering angle sensor and the rise of the vehicle height sensor 40C, it is possible to determine whether the change in the vehicle height difference between the left and right sides is due to the driver's will or due to disturbance (crosswind). good.

In this manner, by using the output of the steering angle sensor in addition to the output of the vehicle height sensor 40C, it is possible to accurately detect a situation in which a relatively strong crosswind is blowing. That is, the situation in which a relatively strong crosswind is blowing as a crosswind environment is that the steering angle is less than a predetermined value or the output of the vehicle height sensor 40C, in addition to the fact that the first state has continued for a predetermined period of time in the predetermined cycle T. may be detected on the condition that the rise of is earlier than the rise of the output of the steering angle sensor.

Further, when the vehicle is provided with the vehicle height sensor 40C, the CPU 100A detects the smoothness of the road surface based on the output of the vehicle height sensor 40C. More specifically, the CPU 100A first determines whether the vehicle height is the vehicle height determination threshold value in a predetermined period T (for example, several seconds (sec)) based on the output of one of the vehicle height sensors 40C provided in the vehicle. It is determined whether or not it is equal to or greater than the threshold value d of 4. However, it is not limited to using the output of one vehicle height sensor 40C, and an average value of vehicle heights detected by a plurality of vehicle height sensors 40C may be used for determination.

If the vehicle height is equal to or greater than the fourth threshold value d, there is a high possibility that the road surface is rough with low smoothness. Therefore, in order to determine whether the road surface is rough with low smoothness, the CPU 100A, when determining that the vehicle height is equal to or greater than the fourth threshold value d, calculates the rate of change of the vehicle height in a predetermined cycle T, It is determined whether or not the second state in which the rate of change is equal to or greater than the fifth threshold e in the period T has continued for a predetermined time.

When the CPU 100A determines that the second state has continued for a predetermined period of time in the predetermined cycle T, the CPU 100A sets a correction value. In this case, there is a high possibility that the unevenness of the road surface continues to exist. In other words, the road is considered to be a rough road having, for example, a poorly paved road surface or an undulating road surface such as ruts on a snowy road. In such a situation, the presence of bumps and ruts on the road surface may cause the steering wheel to be pulled, so the driver is required to drive more carefully.

In order to set the correction value when the second state continues for a predetermined period of time, for example, as shown in FIG. and a correction value that fluctuates so that it increases as it becomes longer, or a proportional function or a predetermined function, or a correction value that is a constant value regardless of the duration, provided that the second state continues for a predetermined time may be stored.

Therefore, the CPU 100A determines that the vehicle height is equal to or greater than the fourth threshold value d in the predetermined cycle T, and the second state, that is, the state in which the speed of change in vehicle height is equal to or greater than the fifth threshold value e, When it is determined at T that it has continued for a predetermined time, a correction value is set based on the relationship shown in FIG. In order to reduce the calculation load, it is not necessary to cause the CPU 100A to perform the process of determining whether the second state has continued for a predetermined period of time. That is, after the CPU 100A determines that the vehicle height is equal to or greater than the fourth threshold value d in the predetermined period T, the correction value corresponding to the duration of the second state is calculated from the relationship between the change speed and the correction value shown in FIG. The selection may be made by the CPU 100A. For example, if the second state has not continued for a predetermined time, 0 is selected as the correction value.

Note that FIG. 8 shows an example in which the second state duration t3>predetermined time in the predetermined cycle T. In FIG. For example, when a variation value is stored in the flash ROM 100B as a correction value, a correction value corresponding to the duration t3 is set.

When CPU 100A sets a correction value (including a case of 0) based on the surrounding conditions, CPU 100A corrects the target speed. More specifically, when only one correction value is calculated using the outputs of the sensors 40A to 40C, the CPU 100A corrects the target speed by subtracting the correction value from the target speed set in step 14. do.

If any one of the illuminance sensor 40A, raindrop sensor 40B, and vehicle height sensor 40C is not provided in the vehicle, 0 is selected as the correction value using the output of the sensor not provided in the vehicle. Further, when the illuminance exceeds the first threshold value a, when the amount of raindrops is less than the second threshold value b, and when the vehicle height difference between the left and right sides is less than the third threshold value c, the first state is the predetermined 0 is selected as the correction value also when the vehicle height is less than the fourth threshold value d, or when the second state does not continue for a predetermined time. Thus, when 0 is selected as the correction value, the target speed set in step 14 is used for subsequent processing.

Moreover, when a plurality of correction values are set, the CPU 100A selects, for example, the largest correction value from the plurality of correction values. Alternatively, instead of this, for example, a final correction value may be obtained by adding a plurality of correction values. However, it is not limited to this. good. As weighting according to priority, for example, when the vehicle frequently travels on rough roads such as snowy roads, the coefficient applied to the correction value calculated based on the rate of change in vehicle height is compared with other coefficients. If the vehicle travels more frequently during the daytime than at nighttime, the coefficient applied to the correction value calculated based on the illuminance can be made smaller than the other coefficients. mentioned. Alternatively, the final correction value may be obtained by adding the weighted correction values.

At step 18, the CPU 100A obtains the current vehicle speed from the vehicle speed sensor 30, and the vehicle speed and the target speed corrected at step 16 (if the correction value is 0, the target speed set at step 14 (same below)). Set the driving assistance level based on

More specifically, CPU 100A first determines whether or not the vehicle speed exceeds the corrected target speed. When the vehicle speed exceeds the corrected target speed, the driving support level is set according to the degree of difference (speed difference) between the vehicle speed and the corrected target speed. For example, a plurality of thresholds (for example, two) are set for driving assistance level setting, and if the speed difference is less than the first threshold, the driving assistance level is set to 1, and the speed difference is set to the first threshold. If the speed difference is greater than or equal to the second threshold and less than the second threshold, the driving assistance level is set to 2, and if the speed difference is greater than or equal to the second threshold, the driving assistance level is set to 3. On the other hand, the CPU 100A sets the driving assistance level to 0, for example, when determining that the vehicle speed is equal to or lower than the corrected target speed.

At step 20, the CPU 100A notifies the driver via the notification device 50 of the need to decelerate the vehicle by outputting a command signal corresponding to the driving support level set at step 18 to the notification device 50 ( (warning) is executed, and the process ends.

However, the driving assistance is not limited to the warning by the notification device 50 described above. For example, if the driving support system 1 is provided with a brake device that controls the brakes of the vehicle or a device that automatically controls the steering of the vehicle for automatic driving, in addition to or instead of the warning described above, Driving control such as brake control and steering control may be executed according to the driving support level. When the driving support level is 0, driving support by warning and driving control described above is not executed.

On the other hand, when the CPU 100A determines in step 12 that the difference between the road width W _X1-X2 and the vehicle width Wv is equal to or greater than a predetermined value (W _X1-X2 -Wv≧predetermined value), the process proceeds to step 22 . In this case, it is considered that the distance between the road width W _X1-X2 and the vehicle width Wv is sufficiently wide and there is no need to execute driving assistance. Therefore, in step 22, the CPU 100A sets the driving assistance level to 0, and then terminates the process.

In the driving assistance device 100 described above, first, the target speed is set based on the acquired speed limit, road width, and vehicle width. Next, based on the output of at least one of the illuminance sensor 40A, the raindrop sensor 40B, and the vehicle height sensor 40C, the current ambient conditions of the vehicle are dark outside, such as at night, in a tunnel, or during bad weather, or a relatively large amount of rainfall. The correction value is set and The target speed is corrected so that it is reduced by the correction value. Then, a driving assistance level is set based on the corrected target speed and the current vehicle speed, and driving assistance corresponding to the driving assistance level is executed. As a result, it is possible to provide driving assistance that is more suited to the current surrounding conditions than driving assistance that is based on the target speed that is set in consideration of only the acquired speed limit, road width, and vehicle width. Therefore, it is possible to encourage the driver to drive more cautiously in order to suppress steering errors in situations where visibility may be poor or where the steering wheel may be taken.

As the ambient condition detector 40, existing sensors such as an illuminance sensor 40A, a raindrop sensor 40B, and a vehicle height sensor 40C are used. Therefore, since it is not necessary to add a new sensor or to add an associated arithmetic processing, it is possible to perform driving assistance according to the surrounding conditions with a simple configuration.

Further, the driving support device 100 described above uses the outputs of the existing sensors 40A to 40C to determine that the current surrounding situation is a situation in which visibility may be poor or a situation in which the steering wheel may be taken. It is a configuration for correcting the target speed set based on. Therefore, a program for correcting the target speed using the output of each sensor 40A to 40C is added to the driving support device programmed only with the function of setting the target speed based on the acquired speed limit, road width, and vehicle width. By incorporating, the driving support device 100 described above can be configured.

Hereinafter, the setting of the target speed will be described using another traveling path different from the traveling path shown in FIG. FIG. 9 shows another example of target speed setting. It is assumed that the traveling road shown in FIG. 9 has a speed limit of 30 km/h, a road width of Wr2, and an intersection and curved mirrors in an area with a traveling direction distance of 40 m to 50 m. It is also assumed that this road exists in an urban area with adjacent buildings. When the map information includes the location information of road attachments, the acquiring unit 102 acquires the road information including the intersection location information and the curved mirror location information in addition to the speed limit and the road width. ing.

On roads where there are intersections and crosswalks, especially when traffic signals are not installed, there is a risk that other vehicles and pedestrians or bicycles who are vulnerable to traffic may jump out across the roadway. In addition, road attachments such as curved mirrors provided on the side of the road can become obstacles that narrow the actual road width. Therefore, it is preferable for the driver to drive carefully, such as by slowing down the vehicle on roads with intersections, pedestrian crossings, and adjuncts to safety. Therefore, the flash ROM 100B stores correction widths (margin widths) for correcting the actual road width, which are set in advance corresponding to, for example, intersections, pedestrian crossings, and adjuncts to roads.

In the example shown in FIG. 9, when the arrangement information of the intersection and the arrangement information of the curved mirror are acquired, the setting unit 104 selects the correction width A by the intersection and the correction width B by the curved mirror in order to correct the road width. . Here, as shown in FIG. 9, for example, the setting unit 104 divides a predetermined distance in front of the vehicle into predetermined intervals (eg, 10 m), and sets the road width and selects the correction width for each divided area. and target speed can be set. Accordingly, the correction widths A and B are selected as correction widths in the region 40m-50m. Then, the setting unit 104 subtracts the selected correction widths A and B from the road width Wr2 of the traveling road. Thereby, the road width W _40-50 (=Wr2-AB) in the region 40m to 50m is calculated. That is, the setting unit 104 calculates the road width for setting the target speed in consideration of the layout of intersections, pedestrian crossings, and road appendages. On the other hand, in the area of 0 m to 40 m, there are no intersections, pedestrian crossings, or adjuncts to the road, so no correction width is set, so the road width is set to Wr2 without correction.

After that, the setting unit 104 sets the target speed based on the speed limit, the vehicle width Wv, and the road width for each area. In the area of 40 m to 50 m, the calculated road width W _40-50 is used as the road width for setting the target speed. In the example shown in FIG. 9, the target speed is set to substantially the same value as the speed limit in the region 10 m to 40 m because the road width Wr2 is sufficiently wider than the vehicle width Wr, and in the region 40 m to 50 m, the road It is set to a value (at least less than the speed limit) corresponding to the difference between the width W _40-50 (=Wr2-AB) and the vehicle width Wv. For example, when the setting unit 104 recognizes the presence of a sidewalk from the acquired road information, the road width obtained by subtracting the sidewalk may be used as the road width W _X1-X2 .

Further, the correction width based on road attachments may be set for each speed limit of the traveling road. For example, on a road with a speed limit of 60 km/h, there is a high possibility that the vehicle is traveling at a higher speed than on a road with a speed limit of 30 km/h. Therefore, for safety reasons, the correction width due to road attachments is relatively wider at a speed limit of 30 km/h than at a speed limit of 60 km/h. is set to

On the other hand, for example, compared to roads with a speed limit of 30 km/h, roads with a speed limit of 60 km/h are more likely to have traffic lights, guardrails, sidewalks, or center lines such as median strips. It is thought that the possibility of jumping out at an intersection or a pedestrian crossing is low. Therefore, the corrected width due to intersections and pedestrian crossings may be set to be narrower as the speed limit is higher. In particular, on roads where the speed limit is 60 km/h or more, the correction width corresponding to intersections and crosswalks may be set to 0 m. Note that the correction width is not limited to being set in advance corresponding to intersections, pedestrian crossings, or road appendages. It may be calculated by

Here, if the map information does not include the location information of the road appendages, the road appendages may be estimated from the road structure in the acquired road information, and the corresponding correction width may be selected. Therefore, in the flash ROM 100B, for example, as shown in FIG. 10, road speeds predetermined for each speed limit (for example, speed limit 30 km/h, 40 km/h, . . . , 60 km/h, . . . ) are stored. A table may be stored showing the relationship between structures and corresponding road width correction widths due to possible road appendages. The road structure referred to in this specification means, for example, whether the road is a suburban road with no adjacent buildings or an urban road with adjacent buildings, and whether there are sidewalks and a central line. is doing.

For example, a road in an urban area where the speed limit is 30 km/h and there are adjacent buildings has a speed limit of 30 km/h compared to a suburban road with no adjacent buildings. There is a high possibility that the appendages are placed in a position that can narrow the road width. Therefore, in the table shown in FIG. 10, for example, the correction width due to the road attachments in the urban area may be set relatively wider than the correction width due to the road attachments in the suburbs.

However, even in an urban area, when a center line or sidewalk is provided, road attachments are arranged so that the road width can be narrowed compared to when there is no center line or sidewalk. unlikely to be Therefore, for example, the correction width when the center line or sidewalk is provided may be set relatively narrower than the correction width when the center line or sidewalk is not provided. Further, in the table shown in FIG. 10, for example, the correction width may be set so as to increase as the speed limit increases. Furthermore, since the vehicle speed is relatively high on roads with a speed limit of 60 km/h, the correction width (corresponding to j in FIG. 10) is set wide regardless of the road structure so as to safely avoid road appendages. may be

Calculation of the road width with reference to the table shown in FIG. 10 will be described. In the example shown in FIG. 9, first, the acquisition unit 102 obtains road information such as "speed limit 30 km/h, urban area, no sidewalk, road width Wr2 in area 0 m to 50 m, and intersection in area 40 m to 50 m". Get information. Next, the setting unit 104 sets the correction width A for the intersection and selects the correction width B for the road appendages (corresponding to c in the table shown in FIG. 10) with reference to the table shown in FIG. Then, the setting unit 104 subtracts the correction widths A and B from the road width Wr2 to set the road width W _40-50 (=Wr2-A-B) in the region of 40 m to 50 m, that is, the target speed. Calculate the road width of

Further, the map information may include, as the road width, road widths that have been corrected in advance with correction widths due to intersections, pedestrian crossings, or adjuncts to roads. That is, the road width for setting the target speed may be acquired by the acquiring unit 102 as a road width that takes into consideration the arrangement of intersections, pedestrian crossings, and road appendages. Therefore, instead of setting the target speed using the road width corrected by the correction width stored corresponding to the intersection or the road width calculated by referring to the table shown in FIG. 10, the road information is directly obtained. The target speed may be set using the corrected road width.

After that, the target speed set in consideration of the road width calculated or obtained according to the arrangement of intersections, pedestrian crossings or road appendages is corrected by the correction unit 106 based on the current surrounding conditions of the vehicle. Therefore, according to the driving assistance device 100, driving assistance with higher safety can be executed according to the surrounding conditions.

Further, for example, when the vehicle is provided with an object detector that detects an object existing in front of the vehicle, the usable road width may be calculated in consideration of the object detected by the object detector. Such object detectors include, for example, a stereo camera composed of a pair of left and right CCD (Charge Coupled Device) cameras or CMOS (Complementary Metal-Oxide Semiconductor) cameras, and radar such as millimeter wave radar or laser radar. , lidar (LIDAR). More specifically, the object detector detects at least parked vehicles, parked bicycles, pedestrians or road appendages and their width in the roadway in front of the vehicle. Then, the setting unit 104 may calculate the road width by subtracting the width of the object detected by the object detector and the correction width set correspondingly from the obtained road width. Calculation of the road width using the object detector will be described with reference to FIG.

In the example shown in FIG. 11, there are parked vehicles in the area of 40m to 50m. The object detector calculates the position and width of the parked vehicle and outputs a signal indicating this information to the driving assistance device 100 . That is, the acquisition unit 102 may be adapted to receive a signal from the object detector. Then, the setting unit 104 sets a correction width C corresponding to the detected object, and subtracts the width of the detected object and the correction width C from the road width (Wr3 in the example shown in FIG. 11). , to calculate the available road width. Therefore, in the area of 40 m to 50 m, the width of the parked vehicle is subtracted from the road width Wr3 to calculate the road width D excluding the width of the parked vehicle, and then the corrected width C is subtracted from the road width D. Thus, the road width W _40-50 (=DC) for setting the target speed is calculated. In other words, by using the object detector, it is possible to calculate the road width that takes into account unexpected avoidance objects such as parked vehicles that are not included in the map information, so that safer driving assistance can be achieved. It can be executed depending on the surrounding conditions.

Note that the above-mentioned stereo camera is susceptible to poor visibility, such as when the outside of the vehicle is dark, such as at night, in a tunnel, or during bad weather, or when there is a relatively large amount of rainfall. be. Therefore, when it is detected that the current surrounding situation of the vehicle is likely to cause poor visibility based on the output of the illuminance sensor 40A or the raindrop sensor 40B, driving assistance such as generating a reaction force on the accelerator pedal as described above is performed. In addition, driving assistance such as forcibly turning on the headlights may be performed in order to improve the detection accuracy of the stereo camera.

Also, the first threshold value a or the second threshold value b to be compared with the output of the illuminance sensor 40A or the raindrop sensor 40B for detecting a situation that may result in poor visibility as the current surrounding situation of the vehicle is set to the exposure situation of the stereo camera. etc., may be taken into consideration for correction. For example, when the amount of light captured by the stereo camera is equal to or less than the threshold for determining the amount of light, the current surroundings of the vehicle may become poor visibility by increasing the first threshold a or the second threshold b. It is possible to detect the situation at an early stage.

Here, in step 18 shown in FIG. 4, when the vehicle speed exceeds the corrected target speed, the CPU 100A, that is, the support unit 108, sets the driving support level according to the degree, but this is not the only option. is not. For example, the support unit 108, that is, in step 18, the CPU 100A may execute the following processing when the target speed is set to change for each area as shown in FIGS. 9 and 11. .

First, when the vehicle speed Vv is obtained from the vehicle speed sensor 30, the support unit 108 calculates the deceleration required to make the vehicle speed Vv reach the target speed at the change point where the target speed changes for each region. More specifically, the support unit 108 calculates the predicted arrival time (traveling direction distance X/current deceleration (that is, the vertical axis is the target speed and the horizontal axis is the predicted arrival time ) is calculated.

Then, when the calculated deceleration is within a predetermined range (for example, 0.0 to 1.0), the support unit 108 determines whether the current vehicle speed Vv is equal to or lower than the target speed or the driver performs a normal braking operation. It is determined that it is not necessary to execute driving assistance (that is, the driving assistance level is set to 0).

On the other hand, when the deceleration is greater than or equal to the first predetermined value (1.0 in the above example) that defines the upper limit of the predetermined range described above, the support unit 108 determines that it is necessary to perform driving support. , and sets the driving assistance level according to the calculated deceleration. The driving assistance level is set to 1 if the deceleration is greater than or equal to a first predetermined value and less than a second predetermined value (eg, 2.0). Further, the driving assistance level is set to 2 when the deceleration is greater than or equal to a second predetermined value and less than a third predetermined value (eg, 3.0). Further, the driving assistance level is set to 3 when the deceleration is greater than or equal to the third predetermined value.

After that, the support unit 108 executes driving support processing according to the set driving level. In this way, by setting the driving support level in consideration of deceleration when the target speed changes for each area, it is possible to quickly notify the driver that the vehicle needs to be decelerated. becomes possible. Therefore, it is possible to perform driving assistance that is highly convincing to the driver, such as allowing the driver who is informed of the fact to perform the braking operation early.

Next, a modified example of the driving assistance process executed by the driving assistance device 100 will be described.
FIG. 12 is a functional block diagram showing a modification of the driving support device 100. As shown in FIG. In this modification, the driving assistance device 100 does not include the correction unit 106 shown in FIG. , referred to as “second setting unit 110”).

The second setting unit 110 sets the target speed based on the speed limit and the road width (or the road width considering the arrangement of intersections) and the vehicle width obtained in the same manner as the first setting unit 104, and separately , the output of the ambient condition detector 40 is used to set the target speed. Therefore, in this modification, for example, step 16 in the flowchart shown in FIG. 4 is changed to a process of setting the target speed based on the surrounding conditions.

In the process of setting the target speed based on the surrounding conditions, the presence or absence of the illuminance sensor 40A, the raindrop sensor 40B, and the vehicle height sensor 40C is determined in the same manner as described in step 16 shown in FIG. Set the target speed according to the sensor output. The relationship between the output of each sensor 40A-40C and the target speed will be described below with reference to FIGS. 13-16.

In order to set the target speed when the illuminance is equal to or less than the first threshold a, the flash ROM 100B stores, for example, as shown in FIG. A proportional function or a predetermined function indicating the relationship with the target speed that fluctuates so as to decrease as It is

In order to set the target speed when the raindrop amount is equal to or greater than the second threshold value b, the flash ROM 100B stores, for example, the raindrop amount when the raindrop amount is equal to or greater than the second threshold value b, as shown in FIG. A proportional function or a predetermined function that indicates the relationship between the target speed and the target speed that fluctuates so that it decreases as this increases, or a constant value regardless of the amount of raindrops on the condition that the amount of raindrops is equal to or greater than the second threshold value b different target velocities are stored.

The flash ROM 100B stores, for example, the , when the duration of the first state (t1 or t2 in the example shown in FIG. 15) is equal to or longer than a predetermined time (<t2), the longer the duration, the smaller the target speed that fluctuates. or a predetermined function, or a target speed that becomes a constant value on the condition that the duration of the first state is equal to or longer than a predetermined time is stored. In addition to the output of the vehicle height sensor 40C, the output of the steering angle sensor may be used in the same manner as described in step 16 shown in FIG.

A state in which the CPU 100A determines that the vehicle height is equal to or greater than the fourth threshold value d in the predetermined period T, and the rate of change in vehicle height is equal to or greater than the fifth threshold value e, that is, the second state is for a predetermined period of time or longer. In order to calculate the target speed when it is determined to continue, for example, as shown in FIG. 16, the duration of the second state (t3 in the example shown in FIG. < t3), a proportional function or a predetermined function indicating the relationship between the duration and the target speed that fluctuates so that the longer the duration is, or the duration of the second state is a predetermined time or more A target speed that is a constant value is stored on the condition that

The target speed calculated from the proportional function or the predetermined function stored in the flash ROM 100B or the target speed that is a constant value is the target speed calculated from the relationship between the outputs of the various sensors 40A to 40C. It is preferable that the following is set in advance for each speed limit (see FIGS. 13 to 16).

Also, when the outputs of the sensors 40A to 40C do not satisfy the above conditions, such as when the illuminance is greater than the first threshold value a, a value substantially the same as the regulated speed is selected as the target speed. It should be noted that in the modified example of the driving support process, similarly to the above, in order to reduce the calculation load, the CPU 100A does not execute the process of comparing the outputs of the various sensors 40A to 40C and the threshold values. A corresponding target speed may be selected from the relationship between the outputs of various sensors shown in FIGS. 13 to 16 or calculated values based thereon and the target speed.

In the modification of the driving support process, the CPU 100A sets the final target speed after calculating the target speed based on the surrounding conditions. That is, in this modification, for example, step 18 shown in FIG. 4 calculates the final target speed from the target speed set in consideration of the speed limit, road width and vehicle width and the target speed set based on the surrounding conditions. Changed to the selected process.

For example, the CPU 100A selects the target speed with the smallest value among the set target speeds as the optimum target speed. However, the present invention is not limited to this. For example, weighting is performed by multiplying (multiplying) each of the set target speeds by a smaller coefficient as the priority is higher, and among the weighted target speeds, the smallest value is selected. You may As for the order of priority, for example, when the vehicle frequently travels on rough roads such as snowy roads, the coefficient to be applied to the target speed calculated based on the rate of change of the vehicle height is set smaller than the other coefficients. Alternatively, if the vehicle frequently travels during the daytime, the coefficient to be applied to the target speed calculated based on the illuminance may be increased compared to other coefficients.

In the modified example described above, in addition to the target speed that is set in consideration of the speed limit, road width, and vehicle width, the vehicle speed is adjusted based on the output of at least one of the illumination sensor 40A, the raindrop sensor 40B, and the vehicle height sensor 40C. A target speed is set that takes into account the current surrounding conditions. Therefore, according to the modified example described above, compared with the driving assistance only according to the target speed set in consideration of the speed limit, the road width and the vehicle width, the driving assistance is more responsive to the current surrounding conditions of the vehicle. It is possible to do Therefore, it is possible to encourage the driver to drive more cautiously in order to suppress steering errors in situations where visibility may be poor or where the steering wheel may be taken.

The current position of the vehicle detected using the GPS receiver 10 includes information on latitude and longitude. The CPU 100A may, for example, calculate the theoretical sunset time from the latitude and longitude of the vehicle's current position. Along with this, the CPU 100A may correct the first threshold a to be compared with the output (illuminance) of the illuminance sensor 40A according to the calculated theoretical sunset time. For example, when the sunset time is approaching, by increasing the first threshold value a, it becomes possible to quickly determine that the current surroundings of the vehicle may cause poor visibility.

Here, if the sun's rays to the vehicle are continuously blocked by topographical factors such as ridgelines in mountainous areas or artificial factors such as buildings in urban areas, the actual sunset time may differ from the theoretical sunset. It may be earlier than the time. Therefore, the CPU 100A may, for example, correct the calculated theoretical sunset time to be earlier, thereby increasing the first threshold value a according to the corrected sunset time.

The correction processing of the first threshold value a described above may be executed in parallel with the driving support processing described above.

In the above description, examples of the notification device 50 include the actuator 50A that generates a reaction force on the accelerator pedal and the speaker 50B (and the display screen) provided in the vehicle interior, but the notification device 50 is not limited to this. For example, if the vehicle has a device that automatically tightens the seat belt when the vehicle collides with an obstacle, the driving assistance executed by the CPU 100A is to tighten the seat belt according to the driving assistance level. The driver may be notified that it is necessary to drive the vehicle in a decelerated manner. In addition, in the case where the seat of the driver's seat of the vehicle is vibrated to warn the driver when a predetermined driving condition is established, the seat is vibrated to warn the driver. good too.

REFERENCE SIGNS LIST 10 GPS receiver 20 map database 30 vehicle speed sensor 40 ambient condition detector 40A illuminance sensor 40B raindrop sensor 40C vehicle height sensor 50 notification device 50A actuator 50B speaker 100 driving support device 100A CPU
100B flash ROM
100D communication circuit 102 road information acquisition unit 104 target speed setting unit 106 target speed correction unit 108 driving support unit

Claims (11)

an acquisition unit that acquires road information including the speed limit and road width of the road on which the vehicle is traveling;
a setting unit that sets a target speed based on the road information and the vehicle width;
a correction unit that corrects the set target speed according to the surrounding conditions of the vehicle;
a support unit that executes driving support for notifying a driver that the vehicle needs to be decelerated based on the corrected target speed and vehicle speed;
with
The surrounding situation is at least a situation in which the steering wheel can be taken, out of a situation in which visibility may be poor and a situation in which the steering wheel may be taken.
Driving assistance device. 2. The driving support system according to claim 1, wherein the situation that may cause poor visibility includes brightness outside the vehicle. 3. The driving assistance device according to claim 1 or 2, wherein the situation that may result in poor visibility includes a raining condition. Driving assistance device according to any one of claims 1 to 3, wherein the situation in which the steering wheel can be taken includes a crosswind environment. 5. The driving support system according to claim 4, wherein the crosswind environment is detected based on a vehicle height difference between the left and right sides of the vehicle that is obtained from an output of a vehicle height sensor that detects vehicle height. The driving assistance device according to any one of claims 1 to 5, wherein the conditions under which the steering wheel can be taken include the smoothness of the road surface. 7. The driving support system according to claim 6, wherein the smoothness of the road surface is detected based on the speed of change of the vehicle height obtained from an output of a vehicle height sensor that detects the vehicle height. The setting unit sets the target speed so that it becomes smaller as the value obtained by subtracting the vehicle width from the road width becomes smaller, with the speed limit being the upper limit. The driving support device according to . The road information includes, in addition to the speed limit and the road width, at least layout information of intersections and layout information of road appendages existing on the side of the road;
The driving according to any one of claims 1 to 8, wherein the acquisition unit acquires a road width in consideration of the arrangement of the intersection and the road appendages as the road width for setting the target speed. support equipment. The road information includes, in addition to the speed limit and the road width, at least layout information of intersections and layout information of road appendages existing on the side of the road;
Driving assistance according to any one of claims 1 to 8, wherein said setting unit calculates a road width for setting said target speed in consideration of the arrangement of said intersection and said road appendages. Device. The road information includes at least intersection location information and road structure in addition to the speed limit and the road width,
The acquisition unit acquires the road width considering the layout of the intersection as the road width for setting the target speed, or the setting unit sets the target speed considering the layout of the intersection. Calculate the road width for
The setting unit selects a correction width corresponding to the obtained road structure based on the relationship between the road structure and road appendages that may exist correspondingly, which is predetermined for each speed limit. 9. The driving support device according to claim 1, wherein the road width for setting the target speed is calculated by subtracting the selected correction width from the road width.

Images