JP6819173B2 - Driving support method and driving support device - Google Patents

Description

The present invention relates to a driving support method and a driving support device.

As a technique for issuing an alarm according to the possibility of collision with an object in front of the vehicle, for example, the technique described in Patent Document 1 is known.
The driving support device described in Patent Document 1 starts an alarm to the driver of the own vehicle when the possibility of the vehicle colliding with an object in front of the vehicle becomes higher than a predetermined value.

Japanese Unexamined Patent Publication No. 2016-001498

However, the driving support device described in Patent Document 1 may start an alarm even if the driver is aware of the object in front of the vehicle and intends to operate the brake, which may cause discomfort to the driver. There is.
An object of the present invention is to reduce discomfort to the driver due to excessive warning when a collision with an obstacle in front of the vehicle is predicted.

In the driving support method according to one aspect of the present invention, it is determined whether or not the brake operation of the driver of the vehicle is predicted, it is determined that the obstacle in front of the vehicle collides with the vehicle, and the brake operation of the driver is predicted. If this is not the case, an alarm is issued, and if it is determined that the vehicle and an obstacle collide with each other and the driver's braking operation is predicted, the alarm is prohibited.

According to the present invention, when a collision with an obstacle in front of the vehicle is predicted, it is possible to reduce discomfort to the driver due to an excessive warning.

It is a figure which shows the configuration example of the driving support device which concerns on embodiment. It is a flowchart of an example of the driving support method which concerns on 1st Embodiment. It is a flowchart of an example of the driving support method which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments of the present invention shown below exemplify devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention describes the materials, shapes, and shapes of the components. The structure, arrangement, etc. are not specified as follows. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

(First Embodiment)
(Constitution)
See FIG. The driving support device 1 according to the embodiment of the present invention includes a controller 10, an ambient condition sensor group 20, a traveling state sensor group 30, an electroencephalogram sensor 40, a buzzer 50, and a brake control actuator 60. The controller 10, the surrounding condition sensor group 20, the traveling state sensor group 30, the brain wave sensor 40, the buzzer 50, and the brake control actuator 60 can transmit and receive data, signals, or information by wired communication or wireless communication. ..

The surrounding condition sensor group 20 includes a sensor for detecting an obstacle in front of a vehicle (hereinafter, may be simply referred to as “vehicle”) equipped with the driving support device 1. The ambient condition sensor group 20 includes a radar 21 and a camera 22.
The radar 21 and the camera 22 detect the surrounding conditions of the vehicle such as the relative position between the obstacle (particularly the obstacle in front of the vehicle) existing around the vehicle and the vehicle, and the distance between the obstacle and the vehicle. The radar 21 and the camera 22 output the ambient condition information, which is the detected ambient condition information, to the controller 10.

The traveling state sensor group 30 includes a sensor that detects the traveling state of the vehicle and a sensor that detects a driving operation performed by the driver.
The sensor for detecting the traveling state of the vehicle includes a vehicle speed sensor 31, an acceleration sensor 32, and a yaw rate sensor 33.
Sensors that detect driving operations performed by the driver include an accelerator opening sensor 34, a brake switch 35, and a brake operation amount sensor 36.

The vehicle speed sensor 31 detects the wheel speed of the vehicle and calculates the speed of the vehicle based on the wheel speed. The vehicle speed sensor 31 outputs the calculated vehicle speed information to the controller 10.
The acceleration sensor 32 detects the acceleration in the front-rear direction and the acceleration in the vehicle width direction of the vehicle, and outputs the information of these accelerations to the controller 10.
The yaw rate sensor 33 detects the yaw rate of the vehicle (the rate of change of the rotation angle in the direction in which the vehicle body turns), and outputs the detected yaw rate information to the controller 10.

The accelerator opening sensor 34 detects the accelerator opening of the vehicle and outputs information on the accelerator opening to the controller 10. For example, the accelerator opening sensor 34 detects the amount of depression of the accelerator pedal of the vehicle as the accelerator opening.
The brake switch 35 detects the operating state of the vehicle brake operation by the driver and outputs the operating state information to the controller 10. For example, the brake switch 35 outputs an on state signal when the driver depresses the brake pedal, and outputs an off state signal when the driver releases the brake pedal.

The brake operation amount sensor 36 detects the brake operation amount by the driver and outputs the information of the detected operation amount to the controller 10. For example, the brake operation amount sensor 36 detects the amount of depression of the brake pedal of the vehicle as the brake operation amount.
The vehicle speed information, acceleration information, yaw rate information, accelerator opening information, brake operation operating state information, and brake operation amount information output from the traveling state sensor group 30 to the controller 10 are collectively referred to as " It may be referred to as "driving state information".

The electroencephalogram sensor 40 has a plurality of electrodes attached to the driver's head. The brain wave sensor 40 outputs the driver's brain wave information detected by these plurality of electrodes to the controller 10. The method of attaching these plurality of electrodes to the head is not particularly limited, but for example, the electroencephalogram sensor 40 may be provided with a wearable electrode cap so as to be easily placed on the driver's head.
The controller 10 predicts the driver's intention to brake based on the brain wave information received from the brain wave sensor 40. That is, the driver's braking operation is predicted. For example, the controller 10 may predict the braking operation by the driver by detecting the exercise preparation potential generated in the driver's brain based on the frequency analysis of the detected driver's brain wave. Although it is based on frequency analysis here, it is not limited to frequency analysis, but pattern analysis may be used, that is, any signal analysis can be performed.

The controller 10 is an electronic control unit that controls the operation of the vehicle. The controller 10 includes a processor 11 and peripheral components such as a storage device 12.
The processor 11 may be, for example, a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit).
The storage device 12 may include any of a semiconductor storage device, a magnetic storage device, and an optical storage device. The storage device 12 may include a memory such as a register, a cache memory, a ROM (Read Only Memory) and a RAM (Random Access Memory) used as the main storage device.

The controller 10 may be realized by a functional logic circuit set in a general-purpose semiconductor integrated circuit. For example, the controller 10 may have a programmable logic device (PLD: Programmable Logic Device) such as a field-programmable gate array (FPGA).

The controller 10 predicts whether or not an obstacle in front of the vehicle collides with the vehicle based on the surrounding condition information received from the ambient condition sensor group 20 and the traveling condition information received from the traveling condition sensor group 30. ..
For example, the controller 10 may evaluate the possibility of collision between an obstacle in front of the vehicle and the vehicle based on the surrounding situation information and the traveling state information. The controller 10 may predict whether or not the vehicle collides with an obstacle by comparing the possibility of collision with the warning threshold value.

The collision possibility may be, for example, the estimated collision time (TTC: Time to Collision) between the vehicle and an obstacle. In this case, the controller 10 calculates the TTC by dividing the distance between the obstacle in front of the vehicle and the vehicle by the relative speed between the vehicle and the obstacle. The controller 10 predicts that the vehicle and the obstacle will collide when the TTC is below the warning threshold, and does not predict that the vehicle and the obstacle will collide when the TTC is above the warning threshold.
In the following description, an example of predicting a collision between a vehicle and an obstacle based on a collision prediction time will be described. However, the collision between the vehicle and the obstacle is not limited to the collision prediction time, and may be predicted by using another method.

When it is predicted that an obstacle in front of the vehicle will collide with the vehicle (in this example, the TTC is less than the warning threshold value), the controller 10 determines whether or not to notify the driver of a predetermined warning. .. This alarm may be an alarm that notifies the danger of collision with a front obstacle or an alarm that prompts the brake operation.
At this time, the controller 10 determines whether or not the brake operation by the driver is detected. For example, the controller 10 determines whether or not the brake operation is detected based on the operating state of the brake operation detected by the brake switch 35 and the brake operation amount detected by the brake operation amount sensor 36. When the brake operation is detected, the controller 10 determines that the alarm notification is prohibited.

When the brake operation is not detected, the controller 10 determines whether or not the driver's brake operation is predicted. The controller 10 determines that the alarm is notified when the driver's braking operation is not predicted. For example, the controller 10 may determine that the alarm is notified when the brake operation is not predicted even after the predetermined first standby time has elapsed after predicting that the obstacle in front of the vehicle collides with the vehicle.

When the braking operation is predicted, the controller 10 may determine that the alarm is prohibited. However, if the brake operation is not detected even after the predetermined second standby time has elapsed after the brake operation is predicted, the controller 10 may determine that the alarm is notified.
That is, it is determined that the controller 10 reserves the alarm notification when the brake operation is predicted, and notifies the alarm when the brake operation by the driver is not detected even after the second standby time elapses after the brake operation is predicted. You may. If the braking operation is detected before the lapse of the second standby time, it may be determined that the alarm notification is prohibited.

When it is determined that the alarm is to be notified, the controller 10 drives the buzzer 50 to generate an alarm sound to notify the driver of the alarm. However, the means for the controller 10 to notify the alarm is not limited to the buzzer 50, and other means may be used to notify the alarm. For example, an alarm sound or an alarm message may be output by a speaker, or a visual display for an alarm may be output from a display such as an indicator lamp or a liquid crystal display device.

Further, the controller 10 compares the possibility of collision with the automatic braking threshold value and determines whether or not the collision avoidance brake is automatically operated. For example, when the TTC becomes less than the automatic braking threshold value, the controller 10 determines that the collision avoidance brake is operated.
When it is determined that the collision avoidance brake is operated, the controller 10 drives the brake control actuator 63 to operate the vehicle braking device.
The brake control actuator 63 controls the braking operation by the brake device of the vehicle in response to the control signal from the controller 10.

The second waiting time is an example of the predetermined time described in the claims. The ambient condition sensor group 20 is an example of the first sensor. The electroencephalogram sensor 40 is an example of the second sensor. The buzzer 50 is an example of an alarm.

(motion)
Next, an example of the driving support method according to the first embodiment will be described.
See FIG.
In step S1, the controller 10 acquires the surrounding situation information from the surrounding situation sensor group 20 in order to calculate the TTC as the possibility of collision between the obstacle in front of the vehicle and the vehicle.
In step S2, the controller 10 acquires the vehicle speed information from the vehicle speed sensor 31 as the traveling state information in order to calculate the TTC.
In step S3, the controller 10 calculates the TTC between the obstacle and the vehicle.

In step S4, the controller 10 predicts whether or not the vehicle collides with an obstacle by comparing the TTC with the warning threshold value. When it is predicted that a collision will occur (step S4: Y), the process proceeds to step S5. The process proceeds to step S10 without determining that an alarm is notified when a collision is not predicted (step S4: N). This prohibits alarm notification.

In step S5, the controller 10 determines whether or not the brake operation is detected in order to determine the necessity of the alarm. When the brake operation is detected (step S5: Y), the process proceeds to step S10 without determining that the alarm is to be notified. This prohibits alarm notification. If the brake operation is not detected (step S5: N), the process proceeds to step S6.

In step S6, the controller 10 acquires the output signal of the electroencephalogram sensor 40 in order to determine whether or not the driver intends to operate the brake, that is, to predict the driver's brake operation.
In step S7, the controller 10 determines whether or not the driver's braking operation is predicted. When the brake operation is predicted (step S7: Y), the process proceeds to step S11 in order to reserve the alarm notification. If the brake operation is not predicted (step S7: N), the process proceeds to step S8.

In step S8, the controller 10 determines whether or not the first standby time has elapsed since the prediction that the obstacle in front of the vehicle collides with the vehicle. When the first standby time has not elapsed (step S8: N), the process returns to step S6 and redetermines whether or not the braking operation is predicted.
Processing when the first standby time has elapsed (step S8: Y), that is, when the brake operation is not predicted even after the first standby time has elapsed after predicting that the obstacle in front of the vehicle will collide with the vehicle. Proceeds to step S9.

In step S9, the controller 10 determines to notify the alarm. The controller 10 drives the buzzer 50 to generate an alarm sound to notify the driver of the alarm. After that, the process proceeds to step S10.
In step S10, the controller 10 determines whether or not the vehicle ignition switch (IGN) has been turned off. The process ends when the ignition switch is turned off (step S10: Y). If the ignition switch is not off (step S10: N), the process returns to step S1.

When the brake operation is predicted, in step S11, the controller 10 determines whether or not the brake operation is detected in order to determine whether or not the prediction of the brake operation is correct. When the brake operation is detected (step S11: Y), the process proceeds to step S10 without determining that the alarm is to be notified. This prohibits alarm notification. If the brake operation is not detected (step S11: N), the process proceeds to step S12.

In step S12, the controller 10 determines whether or not the second standby time has elapsed since the brake operation was predicted. If the second waiting time has not yet elapsed (step S12: N), the process returns to step S11.
When the second standby time has elapsed (step S12: Y), that is, when the brake operation is not detected even after the second standby time has elapsed since the brake operation was predicted, the process proceeds to step S9 and an alarm is given. Is notified.

(Effect of the first embodiment)
(1) The surrounding condition sensor group 20 detects an obstacle in front of the vehicle. The controller 10 predicts whether or not the vehicle collides with an obstacle. The controller 10 determines whether or not the braking operation of the driver of the vehicle is predicted. The controller 10 issues an alarm when it is determined that the vehicle collides with an obstacle and the driver's braking operation is not predicted. The controller 10 prohibits the notification of an alarm when it is determined that the vehicle and an obstacle collide with each other and the driver's braking operation is predicted.
As a result, the controller 10 can determine whether or not the driver is aware of the obstacle and intends to perform the braking operation even if the vehicle predicts that the vehicle will collide with the obstacle. Then, when the driver intends to perform the braking operation, by not notifying the alarm, it is possible to avoid causing discomfort to the driver due to an excessive alarm.

(2) The controller 10 notifies an alarm when the driver's brake operation is not detected even after the second standby time elapses after the driver's brake operation is predicted. This makes it possible to notify an alarm when the prediction of the brake operation is incorrect. Therefore, it is possible to avoid an unalarmed state caused by an erroneous prediction of braking operation.

(3) The controller 10 predicts the braking operation by detecting the exercise preparation potential of the driver. By detecting the exercise preparation potential, the driver's braking operation can be predicted with high accuracy.

(Second Embodiment)
Subsequently, the driving support device 1 of the second embodiment will be described.
The timing of braking when the driver feels the danger of a collision with a perceived obstacle differs depending on the individual driver. For example, one driver starts the braking operation from a state where he / she can afford (that is, a state where the TTC is relatively long), while another driver brakes until a state where he / she approaches an obstacle (that is, a state where the TTC is relatively short). The operation may not start.

Therefore, if the time when the controller 10 predicts the collision between the vehicle and the obstacle, that is, the time when the TTC falls below the warning threshold value is too early for the driver, even if the driver recognizes the obstacle, at that time. You may not yet intend to brake. Therefore, the prediction of the brake operation may be delayed, and an excessive alarm may be notified.

Therefore, in the second embodiment, the alarm threshold value is changed according to the timing of the driver's brake operation after the surrounding condition sensor group 20 detects an obstacle. That is, the alarm threshold value is learned from the timing of the driver's brake operation after the surrounding condition sensor group 20 detects an obstacle.
The configuration of the driving support device 1 of the second embodiment is the same as the functional configuration shown in FIG.
The controller 10 changes the warning threshold value according to the timing of the driver's braking operation after the obstacle in front of the vehicle is detected.

For example, the controller 10 may calculate the TTC at that time at the timing of the driver's braking operation after the obstacle in front of the vehicle is detected. Further, for example, the controller 10 may calculate the TTC at that time at the timing of the driver's brake operation performed after the obstacle and the vehicle are predicted to collide with each other and the driver's brake operation is predicted. ..
The controller 10 may learn the alarm threshold value according to the TTC calculated at these time points. For example, the value of TTC calculated at these time points may be used as the alarm threshold value, a positive margin considering the processing delay may be added to TTC as the alarm threshold value, and a constant C larger than 1 may be multiplied by TTC as the alarm threshold value. May be good.

Further, for example, the controller 10 may learn the warning threshold value according to the TTC calculated at the timing when the driver's braking operation is predicted after the obstacle is predicted to collide with the vehicle. However, if the prediction of the brake operation is incorrect (for example, if there is no brake operation even after the second standby time has elapsed after the prediction of the brake operation), the learning of the alarm threshold value may be invalidated.

Next, an example of the driving support method according to the second embodiment will be described.
See FIG.
The processes in steps S21 to S30 are the same as the processes in steps S1 to S10 described with reference to FIG.
When the brake operation is predicted (step S27: Y), in step S31, the controller 10 determines whether or not the brake operation is detected as predicted by the brake operation. When the brake operation is detected (step S31: Y), the process proceeds to step S33 without determining that the alarm is to be notified. This prohibits alarm notification. If the brake operation is not detected (step S31: N), the process proceeds to step S32.

In step S32, the controller 10 determines whether or not the second standby time has elapsed since the brake operation was predicted. If the second waiting time has not yet elapsed (step S32: N), the process returns to step S31.
When the second standby time has elapsed (step S32: Y), the process proceeds to step S9, and an alarm is notified.

In step S33, the controller 10 calculates the current TTC, that is, the TTC at the timing of the driver's braking operation performed after the obstacle and the vehicle are predicted to collide and the driver's braking operation is predicted. To do. After that, the process proceeds to step S34.
In step S34, the controller 10 learns the alarm threshold value according to the TTC calculated in step S33. After that, the process proceeds to step S30.

(Effect of the second embodiment)
(1) The controller 10 evaluates the TTC between the vehicle and the obstacle as the possibility of collision between the vehicle and the obstacle. The controller 10 compares the TTC with the warning threshold value and predicts whether or not the vehicle collides with an obstacle. The controller 10 changes the alarm threshold value according to the timing of the driver's braking operation after the obstacle is detected.
For example, the controller 10 evaluates the TTC at that time at the timing of the driver's brake operation after the obstacle is detected, and changes the alarm threshold value according to the TTC.
As a result, it is possible to learn when the controller 10 predicts a collision between the vehicle and an obstacle according to the timing of the braking operation of each driver. Therefore, it is possible to avoid an excessive warning by predicting the collision between the vehicle and the obstacle too early for the driver.

It goes without saying that the present invention includes various embodiments not described here. Therefore, the technical scope of the present invention is defined only by the matters specifying the invention relating to the reasonable claims from the above description.

1 ... Driving support device, 10 ... Controller, 11 ... Processor, 12 ... Storage device, 20 ... Surrounding condition sensor group, 21 ... Radar, 22 ... Camera, 30 ... Driving state sensor group, 31 ... Vehicle speed sensor, 32 ... Accelerometer , 33 ... Yaw rate sensor, 34 ... Accelerometer opening sensor, 35 ... Brake switch, 36 ... Brake operation amount sensor, 40 ... Brain wave sensor, 50 ... Buzzer, 60 ... Brake control actuator

Claims (5)

Sensors detect obstacles in front of the vehicle
The controller predicts whether the vehicle and the obstacle will collide,
The controller determines whether or not the braking operation of the driver of the vehicle is predicted.
The controller issues an alarm when it is determined that the vehicle and the obstacle collide and the braking operation of the driver is not predicted, and it is determined that the vehicle collides with the obstacle and the driver's brake operation is not predicted. When a brake operation is predicted, notification of an alarm is prohibited , it is determined whether or not a predetermined time has elapsed after the driver's brake operation is predicted, and even if the predetermined time elapses, the driver's Notifies an alarm when braking operation is not detected ,
A driving support method characterized by that. The controller evaluates the possibility of collision between the vehicle and the obstacle.
The controller compares the collision possibility with the warning threshold value to predict whether or not the vehicle and the obstacle collide with each other.
The controller changes the alarm threshold according to the timing of the driver's braking operation after the obstacle is detected.
The driving support method according to claim 1 , wherein the driving support method is characterized. The controller evaluates the possibility of collision at that time at the timing of the driver's braking operation after the obstacle is detected.
The driving support method according to claim 2 , wherein the controller changes the alarm threshold value according to the collision possibility evaluated at the timing of the driver's brake operation. The driving support method according to any one of claims 1 to 3 , wherein the braking operation is predicted by detecting the exercise preparation potential of the driver. The first sensor that detects obstacles in front of the vehicle,
A second sensor that detects the intention of the driver of the vehicle to operate the brake,
An alarm that generates an alarm and
Whether or not the obstacle detected by the first sensor collides with the vehicle is predicted, and whether or not the driver's braking operation is predicted based on the intention of the braking operation detected by the second sensor. When it is determined that the vehicle and the obstacle collide with each other and the driver's braking operation is not predicted, the alarm device is driven to notify the alarm, and the vehicle collides with the obstacle. Then, when it is determined that the driver's brake operation is predicted, the notification of the alarm is prohibited, and it is determined whether or not a predetermined time has elapsed after the driver's brake operation is predicted, and the predetermined time is determined. A controller that notifies an alarm when the driver's braking operation is not detected even after the lapse of time .
A driving support device characterized by being equipped with.

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