JP2020121575A - Operation support device of vehicle - Google Patents

Abstract

To enhance the driving feeling when both ACC and BSM are executed.SOLUTION: An operation support ECU 10 is configured to during execution of preceding vehicle follow-up control: determine whether or not an indicator on a passing lane side PL of the BSM operates when winker operation to the passing lane side is detected; and change the target acceleration to a target acceleration for passing that is higher than a target acceleration for following up and traveling to a preceding vehicle when the indicator does not operate. It ceases to change the target acceleration to the target acceleration for passing when the indicator operates.SELECTED DRAWING: Figure 7

Description

The present invention relates to a vehicle driving assistance device that causes a vehicle to travel so as to follow a preceding vehicle.

Conventionally, with the preceding vehicle following function that keeps the distance between the own vehicle and the preceding vehicle at a predetermined distance, the own vehicle follows the preceding vehicle and runs at a constant speed when the preceding vehicle does not exist. A driving support device for performing high speed traveling control is known. The constant speed traveling control with the preceding vehicle following function is called adaptive cruise control (ACC), and hence the constant speed traveling control with the preceding vehicle following function is hereinafter referred to as ACC.

During the execution of ACC, a target acceleration for causing the host vehicle to follow the preceding vehicle is calculated, and the engine or the brake is controlled based on this target acceleration. In the device proposed in Patent Document 1, when the own vehicle is made to follow the preceding vehicle, if it is detected that the driver intends to overtake the preceding vehicle based on the operating state of the winker, the ACC It is configured to increase the target acceleration.

JP, 2017-202742, A

By the way, the driving support device is often provided with various driving support functions in addition to ACC. A blind spot monitor (called BSM) is known as one of them. The BSM monitors another vehicle that is traveling behind the vehicle in an adjacent lane adjacent to the lane of travel of the vehicle, and detects another vehicle that the driver should be careful of (referred to as a vehicle of attention), This is a system that calls the driver's attention by turning on or blinking indicators. The attention target vehicle is, for example, another vehicle existing in a blind spot area that is not reflected in the side mirror of the own vehicle, and another vehicle predicted to enter the blind spot area within a predetermined time.

When the driving assistance device has both the ACC and BSM functions, the following problems are concerned.

For example, consider a case where the driver operates the winker in an attempt to pass the preceding vehicle when the own vehicle is made to follow the preceding vehicle by ACC. In this case, in the ACC, the operation of the turn signal on the overtaking lane side is detected, and the target acceleration is switched from the target acceleration for following the preceding vehicle up to the target acceleration for overtaking higher than that.

However, when there is another vehicle that is approaching the host vehicle from behind the overtaking lane, the BSM has detected the target vehicle. In this case, when the blinker operation is performed, the driver is alerted by blinking the indicator or the like, so that the driver stops overtaking and stops the steering wheel operation.

On the other hand, in ACC, the target acceleration is switched from the target acceleration for following the preceding vehicle to the target acceleration for overtaking in conjunction with the turn signal operation, so that the host vehicle accelerates. Therefore, the driver may feel uncomfortable because the vehicle accelerates although the driver's intention to overtake is lost due to the BSM alerting. As a result, a comfortable driving feeling cannot be obtained for the driver.

The present invention has been made to solve the above problems, and an object of the present invention is to improve the driving feeling when both ACC and BSM are performed.

In order to achieve the above object, the features of the present invention are:
Preceding vehicle follow-up control, which is control for calculating a target acceleration for causing the subject vehicle to follow the preceding vehicle while keeping the inter-vehicle distance from the subject vehicle to the preceding vehicle at a predetermined distance, and causing the subject vehicle to travel at the target acceleration When performing a turn signal operation on the overtaking lane side while performing the preceding vehicle following control, the target acceleration of the host vehicle is higher than the target acceleration for following the preceding vehicle. A preceding vehicle following control means (10) for changing to a target acceleration for overtaking;
Blind spot monitoring means that monitors another vehicle traveling behind the vehicle in the adjacent lane adjacent to the lane of the own vehicle and alerts the driver when the other vehicle that the driver should be aware of is detected. (20) In the vehicle driving support device including
During the execution of the preceding vehicle following control, it is judged by the blind spot monitor means whether or not another vehicle which the driver should be careful of is detected in the overtaking lane (S14, S22), and the other vehicle which the driver should be careful of. Is detected in the overtaking lane, acceleration limiting means (S14: No, S16, S22: Yes, S23) for preventing the target acceleration of the host vehicle from being set to the target acceleration for overtaking is provided. There is something.

The vehicle driving assistance device of the present invention includes a preceding vehicle following control means and a blind spot monitoring means. The preceding vehicle follow-up control means is a control for calculating a target acceleration for causing the own vehicle to follow the preceding vehicle while keeping the inter-vehicle distance from the own vehicle to the preceding vehicle at a predetermined distance, and causing the own vehicle to run at the target acceleration. The preceding vehicle following control is executed. Further, the preceding vehicle follow-up control means, when the winker operation on the overtaking lane side is detected during the execution of the preceding vehicle follow-up control, the target acceleration of the own vehicle is more than the target acceleration for causing the preceding vehicle to follow. Change to a higher target acceleration for overtaking. Therefore, when the driver performs a turn signal operation in an attempt to pass the preceding vehicle, the target acceleration for overtaking is calculated in conjunction with the blinker operation. As a result, the host vehicle can be accelerated in accordance with the driver's overtaking intention.

The blind spot monitoring means monitors another vehicle traveling in the rear of the own vehicle in the adjacent lane adjacent to the traveling lane of the own vehicle, and when the other vehicle that should be noted by the driver is detected, the driver is alerted. Evoke. For example, when the blind spot monitoring means detects another vehicle existing in a blind spot area not reflected in the side mirror of the own vehicle and another vehicle predicted to enter the blind spot area, the blind spot monitor means the other vehicle (target vehicle). To alert the driver of the presence of. For example, the blind spot monitor means, in the state where the vehicle subject to attention is detected, if a turn signal operation in the direction in which the vehicle subject to attention is detected is detected, the blind spot monitoring means is linked with the turn signal operation and the vehicle subject to attention is detected. Inform the driver of the existence of. In this case, the blind spot monitor means alerts the driver at the first alert level when the vehicle targeted for attention is detected, and detects the turn signal operation in the direction in which the vehicle targeted for attention is detected. The alerting level may be switched to the second alerting level higher than the first alerting level.

For example, if a blinker operation to the overtaking lane is detected while the preceding vehicle following control is being performed, or if the blind spot monitor detects a vehicle to be watched in the overtaking lane, the driver is alerted. Therefore, the driver stops passing and stops operating the steering wheel. Therefore, it is not preferable to accelerate the own vehicle by ACC.

Therefore, the vehicle driving assistance device of the present invention includes an acceleration limiting means. The acceleration limiting means determines whether or not another vehicle which the driver should be careful of is being detected in the overtaking lane by the blind spot monitoring means during execution of the preceding vehicle following control, and the other vehicle which the driver should be careful of is overtaking lane. If the target acceleration of the host vehicle is detected, the target acceleration of the own vehicle is not set to the target acceleration for overtaking. For example, the acceleration limiting means stops the preceding vehicle following control means from changing the target acceleration of the own vehicle to the target acceleration for overtaking. Therefore, the target acceleration is prevented from being unnecessarily increased.

As a result, according to the present invention, unnecessary acceleration when both ACC and BSM are performed can be suppressed, and the driving feeling can be improved.

In the above description, in order to help understanding of the invention, the reference numerals used in the embodiments are attached in parentheses to the configuration requirements of the invention corresponding to the embodiment. It is not limited to the embodiment defined by.

It is a schematic system block diagram of the driving assistance device of the vehicle which concerns on this embodiment. It is a top view which shows the position of a radar sensor and a camera sensor. It is a front view of the side mirror provided with the indicator. It is a top view showing a blind spot area and an attention target. It is a graph showing a target inter-vehicle time map. It is a flowchart showing a winker interlocking target acceleration request limiting routine. FIG. 6 is a plan view showing a scene in which the inter-vehicle shortening is permitted and a scene in which the inter-vehicle shortening is not permitted due to a turn signal interlocking target acceleration request. It is a flow chart showing a modification of a blinker interlocking target acceleration demand restriction routine.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic system configuration diagram of a vehicle driving assistance device of the present embodiment.

The vehicle driving assistance device according to the present embodiment is applied to a vehicle (hereinafter, may be referred to as “own vehicle” to distinguish from other vehicles), and the driving assistance ECU 10 and the blind spot monitor ECU 20 are applied. (Hereinafter referred to as BSM/ECU), an engine ECU 30, a brake ECU 40, and a meter ECU 50.

These ECUs are electric control units (Electric Control Units) having a microcomputer as a main part, and are connected to each other via CAN (Controller Area Network) 100 so that information can be transmitted and received mutually. In this specification, the microcomputer includes a CPU, a ROM, a RAM, a non-volatile memory, an interface I/F, and the like. The CPU realizes various functions by executing instructions (programs, routines) stored in the ROM. Some or all of these ECUs may be integrated into one ECU.

Further, the CAN 100 is connected to a plurality of types of vehicle state sensors 60 that detect a vehicle state and a plurality of types of driving operation state sensors 70 that detect a driving operation state. The vehicle state sensor 60 includes, for example, a vehicle speed sensor that detects the traveling speed of the vehicle, a longitudinal acceleration sensor that detects the longitudinal acceleration of the vehicle, a lateral acceleration sensor that detects the lateral acceleration of the vehicle, and a yaw rate of the vehicle. For example, a yaw rate sensor for detecting.

The driving operation state sensor 70 detects an accelerator operation amount sensor that detects an operation amount of an accelerator pedal, a brake operation amount sensor that detects an operation amount of a brake pedal, a brake switch that detects whether or not a brake pedal is operated, and a steering angle. The steering angle sensor, the steering torque sensor for detecting the steering torque, the shift position sensor for detecting the shift position of the transmission, the winker switch for detecting the operation of the winker lever, and the like.

Information (referred to as sensor information) detected by the vehicle state sensor 60 and the driving operation state sensor 70 is transmitted to the CAN 100. Each ECU can appropriately use the sensor information transmitted to the CAN 100.

The driving assistance ECU 10 is an electronic control device for assisting the driver's driving operation, and maintains the vehicle-to-vehicle distance from the preceding vehicle while maintaining the inter-vehicle distance between the preceding vehicle and the own vehicle at an appropriate distance according to the vehicle speed. When the vehicle follows the vehicle and the preceding vehicle does not exist, ACC, which is a control for driving the host vehicle at a constant speed at the vehicle speed set by the driver, is performed. This supports the driver's driving operation (pedal operation).

The driving assistance ECU 10 is connected to the front camera sensor 11, the front radar sensor 12, and the ACC switch 13.

As shown in FIG. 2, the front camera sensor 11 is arranged above the front window in the vehicle compartment. The front camera sensor 11 acquires an image (camera image) of the front area of the own vehicle, and from the image, object information (distance to the object and direction of the object, etc.) and a lane in which the own vehicle is traveling are defined. Get lane information about the white line. The front camera sensor 11 supplies information on the detected three-dimensional object and lane information to the driving assistance ECU 10.

The forward radar sensor 12 is, for example, a millimeter wave radar device, and includes a millimeter wave transmitting/receiving unit and a processing unit. As shown in FIG. 2, the front radar sensor 12 is arranged at the front end of the host vehicle and at the center in the vehicle width direction. The millimeter wave transmission/reception unit transmits a millimeter wave centered on a radar axis extending straight ahead of the host vehicle and propagating with a predetermined angular spread in the left and right directions from the radar axis. The millimeter wave is reflected by an object (for example, another vehicle, a pedestrian, a motorcycle, etc.). The millimeter wave transmission/reception unit receives this reflected wave. The processing unit detects an object based on the received reflected wave, and obtains object information such as a distance to the object, a relative speed of the object with respect to the own vehicle, and an azimuth of the object with respect to the own vehicle by calculation. The front radar sensor 12 supplies the detected three-dimensional object information (three-dimensional object information) to the driving assistance ECU 10.

The driving assistance ECU 10 corrects the object information acquired by the front radar sensor 12 based on the object information acquired by the front camera sensor 11 to acquire final object information used for ACC described later.

The ACC switch 13 is a switch operated when the driver wants to start ACC and when setting ACC. The ACC switch 13 transmits the following operation signals to the driving assistance ECU 10.
(1) Turning on/off the driving support function (2) Switching between constant speed control mode and follow-up control mode (3) Setting vehicle speed for constant-speed traveling (set vehicle speed) (4) Setting inter-vehicle distance in follow-up control mode (Long/medium/short)

Here, the ACC will be described. The driving assistance ECU 10 implements ACC when the ACC driving assistance is set to ON by the ACC switch 13. When the ACC switch 13 selects the constant speed control mode in executing the ACC, the driving assistance ECU 10 is a constant speed control that causes the host vehicle to travel at the constant speed at the set vehicle speed set by the ACC switch 13. Take control.

Further, when the follow-up control mode is selected by the ACC switch 13 and there is a preceding vehicle traveling ahead of the host vehicle, the driving assistance ECU 10 determines that the preceding vehicle is based on the preceding vehicle information. Preceding vehicle tracking control, which is control for causing the own vehicle to follow the preceding vehicle while maintaining the inter-vehicle distance to the own vehicle at an appropriate distance according to the vehicle speed, is performed. On the other hand, when there is no preceding vehicle traveling ahead of the host vehicle, the driving assistance ECU 10 carries out the above-mentioned constant speed control.

While the ACC (constant speed control or preceding vehicle follow-up control) is being performed, the driving assistance ECU 10 calculates a target acceleration and outputs a driving force command indicating a required driving force corresponding to a deviation between the target acceleration and the actual acceleration. It is transmitted to the engine ECU 30. This eliminates the need for the driver to operate the pedal. Acceleration distinguishes between acceleration and deceleration by its sign. A positive value represents acceleration, and a negative value represents deceleration. The expressions that acceleration is large (small) and deceleration is large (small) mean that the absolute value is large (small).

The driving support device in the present embodiment has both ACC and BSM functions. The target acceleration for ACC differs depending on the operating condition of the BSM. Therefore, before describing the calculation of the target acceleration for ACC, the BSM will be described first.

The BSM/ECU 20 is a control device that is the core of the Blind Spot Monitor System. A right rear radar sensor 21R, a left rear radar sensor 21L, a right indicator 22R, and a left indicator 22L are connected to the BSM/ECU 20.

The right indicator 22R and the left indicator 22L are for alerting the driver. The right indicator 22R is incorporated in the right side mirror, the left indicator 22L is incorporated in the left side mirror, and both have the same configuration. Hereinafter, when it is not necessary to distinguish between the right indicator 22R and the left indicator 22L, both are referred to as the indicator 22.

The indicator 22 is configured by incorporating an LED in a part of a region where the mirror of the side mirror SM is provided as shown in FIG. 3 (representing the right indicator 22R). In FIG. 3, an enlarged view of the indicator 22 is shown on the right side thereof. Each of the indicators 22 lights or blinks independently left and right by a lighting signal or a blinking signal supplied from the BSM/ECU 20.

The right rear radar sensor 21R is a radar sensor provided at the right rear corner of the vehicle body as shown in FIG. 2, and the left rear radar sensor 21L is at the left rear corner of the vehicle body as shown in FIG. It is a radar sensor provided. The right rear radar sensor 21R and the left rear radar sensor 21L have the same configuration except that the detection areas are different. Hereinafter, when it is not necessary to distinguish between the right rear radar sensor 21R and the left rear radar sensor 21L, both are referred to as the rear side radar sensor 21.

The rear side radar sensor 21 is, for example, a millimeter wave radar device similar to the front radar sensor 12, detects an object based on the transmitted reflected wave of the millimeter wave, and detects the distance to the object and the own vehicle of the object. The object information such as the relative speed with respect to the vehicle and the azimuth of the object with respect to the own vehicle is obtained by calculation.

The right rear radar sensor 21R has a left and right rear corner of the vehicle body as a detection area within a range of a predetermined left and right angle around the radar axis directed diagonally rearward from the right rear corner portion of the vehicle body. The detection area is a range of a predetermined left and right angle centered on the radar axis directed diagonally rearward to the left from the section. The detection area of the right rear radar sensor 21R includes a blind spot area (right blind spot area) that is not reflected by the right side mirror. Further, the detection area of the left rear radar sensor 21L includes a blind spot area (left blind spot area) that is not reflected by the left side mirror.

The rear side radar sensor 21 has information on the detected three-dimensional object, for example, information indicating the distance between the own vehicle and the three-dimensional object, the relative speed between the own vehicle and the three-dimensional object, the orientation of the three-dimensional object with respect to the own vehicle (hereinafter , Rear surrounding information) to the BSM/ECU 20.

Since the BSM system is provided mainly for informing the driver that another vehicle exists in the blind spot area, the three-dimensional object is hereinafter referred to as another vehicle.

As shown in FIG. 4, the BSM/ECU 20 stores the relative positions of the right blind spot region RR and the left blind spot region RL with respect to the host vehicle C1. The right blind spot region RR is preset so as to include a region that is not reflected by the right side mirror (is likely to become a blind spot), and the left blind spot region RL is a region that is not reflected by the left side mirror (is likely to become a blind spot). The area is preset to include the area. When it is not necessary to distinguish between the right blind spot region RR and the left blind spot region RL, both are referred to as a blind spot region R. The blind spot region R is set, for example, in the range of 0.5 m to 3.5 m outward from the left and right sides of the vehicle body in the vehicle left-right direction, and in the range of 1 m in front of the vehicle body rear end to 4 m in the rear direction. .. The blind spot region R is set in a range suitable for the vehicle, and is not limited to this range.

The BSM/ECU 20 determines, based on the rear surrounding information supplied from the rear side radar sensor 21, whether or not there is another vehicle in which the vehicle body is partially included in this blind spot area R, and the blind spot area R If it is determined that another vehicle exists, the other vehicle is set as the alert target. For example, in the example shown in FIG. 4, the other vehicle C2 running side by side in the blind spot region RR in the right lane adjacent to the traveling lane of the host vehicle C1 is to be alerted. Hereinafter, another vehicle that is the target of alerting may be referred to as a target vehicle.

Further, the BSM/ECU 20 determines whether or not there is another vehicle that is predicted to enter the blind spot region R within the set time based on the rear surrounding information supplied from the rear side radar sensor 21, When it is determined that there is another vehicle that is predicted to enter the blind spot area R within the set time, the other vehicle is set as the alerting target. For example, in the example shown in FIG. 4, the other vehicle C3 that is rapidly approaching the blind spot region RL in the left lane adjacent to the traveling lane of the host vehicle C1 is to be alerted.

When the vehicle subject to attention exists, the BSM/ECU 20 turns on the indicator 22 corresponding to the left and right positions of the blind spot region R where the vehicle subject to attention exists or approaches. That is, when the attention target vehicle is present in or approaches the right blind spot region RR, the right indicator 22R is turned on, and when the attention target vehicle is present in or approaches the left blind spot region RL, the left indicator 22L. Light up. As a result, the driver can be notified of the presence of another vehicle that is not reflected in the side mirror.

In addition, the BSM/ECU 20 reads a turn signal operation signal transmitted to the CAN 100 in a state where the indicator 22 is turned on. Then, when a turn signal actuation signal in the same direction as the direction of the indicator 22 that is lit (right in the case of the right indicator 22R, left in the case of the left indicator 22L) is received, that is, the turn signal actuation in the direction in which the target vehicle exists. When the signal is received, the indicator 22 blinks (lights up→blinks).

In a situation where the target vehicle is detected and the indicator 22 is lit, when the driver performs a turn signal operation to turn in the direction in which the target vehicle is present, the indicator 22 blinks. This raises the alert level for the driver. In this way, the driver can be confirmed whether the steering wheel operation is okay, and the steering wheel operation can be stopped depending on the situation.

The BSM/ECU 20 transmits to the CAN 100 a signal (referred to as a BSM status signal) representing a status in which the indicator 22 is lit and a status in which the indicator 22 is blinking. The BSM status signal also includes information that can determine the direction (right or left) of the operating indicator 22. Therefore, in each ECU, the operating status of the indicator 22 can be grasped on the right and left sides through the CAN 100.

The engine ECU 30 is connected to the engine actuator 31. The engine actuator 31 is an actuator for changing the operating state of the internal combustion engine 32. In the present embodiment, the internal combustion engine 32 is a gasoline fuel injection/spark ignition type/multi-cylinder engine and is provided with a throttle valve for adjusting the intake air amount. The engine actuator 31 includes at least a throttle valve actuator that changes the opening of the throttle valve. The engine ECU 30 can change the torque generated by the internal combustion engine 32 by driving the engine actuator 31. The torque generated by the internal combustion engine 32 is transmitted to a drive wheel (not shown) via a transmission (not shown). Therefore, the engine ECU 30 can control the driving force of the host vehicle and change the acceleration state (acceleration) by controlling the engine actuator 31.

The brake ECU 40 is connected to the brake actuator 41. The brake actuator 41 is provided in a hydraulic circuit between a master cylinder (not shown) that pressurizes hydraulic oil by the depression force of a brake pedal and a friction brake mechanism 42 provided on the left and right front wheels. The friction brake mechanism 42 includes a brake disc 42a fixed to the wheels and a brake caliper 42b fixed to the vehicle body. The brake actuator 41 adjusts the hydraulic pressure supplied to the wheel cylinder incorporated in the brake caliper 42b according to an instruction from the brake ECU 40, and operates the wheel cylinder by the hydraulic pressure to press the brake pad against the brake disc 42a to cause friction. Generates braking force. Therefore, the brake ECU 40 can control the braking force of the host vehicle by controlling the brake actuator 41.

The meter ECU 50 is connected to a display unit 51 and left and right turn signals 52 (which means a turn signal lamp, which may also be called a turn lamp). The display device 51 is, for example, a multi-information display provided in front of the driver's seat, and displays various information in addition to the display of measured values of meters such as vehicle speed. For example, when the meter ECU 50 receives a display command according to the driving support state from the driving support ECU 10, the meter ECU 50 causes the display 51 to display the screen specified by the display command.

The meter ECU 50 also includes a winker drive circuit (not shown). When the meter ECU 50 obtains the information of the turn signal switch via the CAN 100 and detects that the turn signal switch is turned on, it blinks the turn signal 52 in the direction (right, left) specified by the turn signal switch turned on. Further, the meter ECU 50 transmits the blinker blinking information indicating that the blinker 52 is in the blinking state to the driving assistance ECU 10, while the blinker 52 is blinking. Therefore, the driving assistance ECU 10 can grasp the blinking state (operating state) of the left and right winkers 52. The driving assistance ECU 10 or the meter ECU 50 may be configured to directly connect the turn signal switch and acquire the information of the turn signal switch.

<Calculation of target acceleration in ACC>
Next, a method of calculating the target acceleration in the ACC performed by the driving support ECU 10 will be described. The driving assistance ECU 10 is a target acceleration for tracking that is a target acceleration for follow-up vehicle tracking control, a target acceleration for constant speed traveling that is a target acceleration for constant speed control, and a target acceleration when traveling on a curved road. The target acceleration for curve running is calculated in parallel at a predetermined calculation cycle. Then, the minimum value of the three target accelerations (following target acceleration, constant speed traveling target acceleration, curve traveling target acceleration) is selected, and the selected target acceleration is set as the final target acceleration. ..

<Calculation of target acceleration for tracking>
Based on the three-dimensional object information obtained by the front camera sensor 11 and the front radar sensor 12, the driving assistance ECU 10 determines whether or not another vehicle exists in front of the lane in which the vehicle is traveling (own lane), When another vehicle exists ahead of the own lane, the other vehicle closest to the own vehicle is selected as the preceding vehicle. When the preceding vehicle is present, the driving assistance ECU 10 repeatedly calculates the following target acceleration at a predetermined calculation cycle.

When calculating the target acceleration for tracking, the driving assistance ECU 10 calculates the target inter-vehicle time when the host vehicle follows the preceding vehicle. The driving assistance ECU 10 calculates the target inter-vehicle time based on the vehicle speed Vn detected by the vehicle speed sensor and the set inter-vehicle distance (long/medium/short) set and stored by the driver. The driving assistance ECU 10 stores a target inter-vehicle time map. As shown in FIG. 5, the target inter-vehicle time map has a characteristic in which the target inter-vehicle time td* is set to be shorter as the vehicle speed Vn is faster and the target inter-vehicle distance is shorter. The driving assistance ECU 10 calculates the target inter-vehicle time td* by applying the vehicle speed Vn and the set inter-vehicle distance to the target inter-vehicle time map.

The driving assistance ECU 10 inputs the target inter-vehicle time td*, preceding vehicle information (preceding vehicle-to-vehicle distance, preceding vehicle relative speed), and the vehicle speed Vn detected by the vehicle speed sensor to calculate the following target acceleration Afollow*.

The driving assistance ECU 10 calculates an acceleration-side tracking target acceleration Afollow1* and a deceleration-side tracking target acceleration Afollow2* as shown in the following equations (1) and (2). Driving support ECU10, when the speed reduction side following target acceleration Afollow2 * is a negative value ^{(Afollow2 * <0m / s 2} ) is a deceleration side following target acceleration Afollow2 * employed as follow-up target acceleration Afollow * (Afollow*=Afollow2*), otherwise, the acceleration-side follow-up target acceleration Afollow1 is adopted as the follow-up target acceleration Afollow* (Afollow*=Afollow1*).

Afollow1*=((ΔD×K1)+(Vr×K2))×Ka (1)
Afollow2*=((ΔD×K1)+(Vr×K2)) (2)

Here, ΔD is a vehicle-to-vehicle deviation described later, K1 and K2 are gains, Vr is a preceding vehicle relative speed described later, and Ka is an acceleration side gain. The lower limit of the acceleration-side follow-up target acceleration Afollow1* is set to zero, and is set to zero by the lower limit processing when the calculation result is a negative value. Further, the deceleration-side follow-up target acceleration Afollow2* has an upper limit value set to zero, and is set to zero by the upper limit process when the calculation result is a positive value.

The inter-vehicle deviation ΔD is a value obtained by subtracting the target inter-vehicle distance (calculated by multiplying the target inter-vehicle time td* by the vehicle speed Vn) from the actual preceding inter-vehicle distance. Therefore, when the actual inter-vehicle distance between the preceding vehicles is longer than the target inter-vehicle distance, the inter-vehicle deviation ΔD has a positive value, and acts to increase the follow-up target acceleration Afollow*. The gains K1 and K2 are positive values for adjustment and may be fixed values or values adjusted by other parameters. The preceding vehicle relative speed Vr is a relative speed of the preceding vehicle with respect to the own vehicle, and is a value obtained by subtracting the vehicle speed of the own vehicle from the vehicle speed of the preceding vehicle. Therefore, when the preceding vehicle is moving away from the host vehicle, the relative speed Vr of the preceding vehicle has a positive value, and acts to increase the follow-up target acceleration Afollow*.

The acceleration side gain Ka is a positive value that adjusts the magnitude of the acceleration side following target acceleration Afollow1 with respect to the deceleration side following target acceleration Afollow2.

When it can be estimated that the driver is overtaking the preceding vehicle, it is preferable to reduce the inter-vehicle distance between the own vehicle and the preceding vehicle. Such a thing can be realized by adjusting the acceleration side gain Ka of the formula (1). For example, when the turn signal operation to the overtaking lane is not detected (when the turn signal is not blinking), the acceleration side gain Ka is set to Ka0, and when the turn signal operation to the passing lane is detected (the turn signal blinks). In the case of the above), the acceleration side gain Ka may be set to Ka1. In this case, the acceleration side gain Ka1 is a value larger than the acceleration side gain Ka0 (Ka1>Ka0). Accordingly, when it can be estimated that the driver is overtaking the preceding vehicle, it is possible to calculate the follow-up target acceleration Afollow* which acts so as to reduce the inter-vehicle distance between the preceding vehicle and the host vehicle.

Hereinafter, the acceleration-side gain Ka suitable for following the preceding vehicle will be referred to as a follow-up acceleration gain Ka0, and the acceleration-side gain Ka suitable for passing will be referred to as an overtaking acceleration gain Ka1. Further, the acceleration side follow-up target acceleration Afollow1 calculated by applying the follow-up acceleration gain Ka0 to the formula (1) is called "following target acceleration", and the overtaking acceleration gain Ka1 is applied to the formula (1). The acceleration-side follow-up target acceleration Afollow1 calculated by the above is called "overtaking target acceleration".

When the drive assist ECU 10 detects a turn signal operation on the overtaking lane side during the preceding vehicle following control, the preceding vehicle does not exist in the overtaking lane, or even if it exists, the vehicle speed of the preceding vehicle is equal to or higher than the vehicle speed of the own vehicle. For example, a turn signal interlocking target acceleration request for switching the acceleration side gain Ka from the following follow-up acceleration gain Ka0 to the overtaking acceleration gain Ka1 (>Ka0) is output. The driving assistance ECU 10 calculates the overtaking target acceleration in accordance with the winker interlocking target acceleration request. As a result, the host vehicle can be accelerated in accordance with the driver's overtaking intention.

By the way, in the situation where the vehicle to be watched is detected by the BSM system and the indicator 22 is lit, if the driver calculates the overtaking target acceleration that works to shorten the inter-vehicle distance in conjunction with the turn signal operation, the driver is instructed to do so. It may give you a feeling of strangeness.

For example, consider a situation in which the vehicle to be watched is detected behind the overtaking lane by the BSM system and the indicator 22 is lit during the preceding vehicle following control. In this situation, when the winker operation on the overtaking lane side is detected, the indicator 22 blinks. As a result, the driver stops overtaking and stops operating the steering wheel. In such a situation, if the own vehicle accelerates so that the inter-vehicle distance between the preceding vehicle and the own vehicle is shortened, the driver feels uncomfortable.

Therefore, the driving support ECU 10 limits execution of the turn signal interlocking target acceleration request (change from the following target acceleration to the overtaking target acceleration) as described below. FIG. 6 shows a winker interlocking target acceleration request limit routine. The driving assistance ECU 10 repeatedly executes the winker-linked target acceleration request limiting routine at a predetermined calculation cycle.

When the winker interlocking target acceleration request limiting routine is activated, the driving support ECU determines in step S11 whether or not ACC is being performed. In a situation where ACC is not executed, it is determined to be "No", and the turn signal interlocking target acceleration request limiting routine is temporarily ended. When the ACC is being executed (S11: Yes), the driving assistance ECU 10 determines in step S12 whether or not the preceding vehicle following control is being executed. In a situation where the preceding vehicle following control is not performed, it is determined to be "No", and the winker interlocking target acceleration request limiting routine is temporarily ended.

When the preceding vehicle following control is being performed (S12: Yes), the driving assistance ECU 10 determines in step S13 whether or not the turn signal is being operated on the overtaking lane side. In this case, the driving assistance ECU 10 reads the blinker blinking information via the CAN 100 and determines whether or not the blinker on the overtaking lane side is blinking.

When it is determined that the winker operation is not performed on the overtaking lane side (S13: No), the driving support ECU 10 advances the process to step S16 and does not execute the turn signal interlocking target acceleration request. As a result, the driving assistance ECU 10 calculates the follow-up target acceleration calculated by applying the follow-up acceleration gain Ka0 to the equation (1). Therefore, the host vehicle can be made to follow the preceding vehicle as it is.

On the other hand, when it is determined that the winker operation is performed on the overtaking lane side (S13: Yes), the driving assistance ECU 10 advances the process to step S14, and the indicator 22 on the overtaking lane side in the BSM is operating (lights up). Medium or blinking). In this case, the driving assistance ECU reads the BSM status signal via the CAN 100 and makes the above determination.

When the indicator 22 on the overtaking lane side is not in operation (light is off, S14: Yes), the driving assistance ECU 10 advances the process to step S15 to execute the turn signal interlocking target acceleration request. As a result, the driving support ECU 10 calculates the overtaking target acceleration calculated by applying the overtaking acceleration gain Ka1 (>Ka0) to the equation (1). As a result, the inter-vehicle distance between the preceding vehicle and the host vehicle is shortened. Therefore, the driver can smoothly pass the preceding vehicle by operating the steering wheel.

On the other hand, when the indicator 22 of the BSM is operating (S14: No), the driving assistance ECU 10 advances the process to step S16 so as not to execute the turn signal interlocking target acceleration request. As a result, the driving assistance ECU 10 calculates the follow-up target acceleration calculated by applying the follow-up acceleration gain Ka0 to the equation (1). Therefore, it is possible to keep the own vehicle as it is and keep the following distance to follow the preceding vehicle.

As a result, in the situation where the indicator 22 on the overtaking lane side is lit, even if the winker operation is performed on the overtaking lane side, the host vehicle does not accelerate so as to reduce the inter-vehicle distance between the preceding vehicle and the host vehicle. This can prevent the driver from feeling uncomfortable.

The driving assistance ECU 10 once ends the turn signal interlocking target acceleration request limiting routine when the process of step S15 or step S16 is performed. Then, the blinker interlocking target acceleration request limiting routine is repeatedly executed at a predetermined calculation cycle.

For example, as shown in FIG. 7A, in the situation where the preceding vehicle follow-up control is performed in which the host vehicle C1 follows the preceding vehicle C4 in the driving lane DL, the driver operates the turn signal to overtake the preceding vehicle C4. If the vehicle subject to attention is not detected in the overtaking lane PL, the target acceleration is switched from the following target acceleration to the overtaking target acceleration. As a result, the inter-vehicle distance between the preceding vehicle and the host vehicle is shortened.

On the other hand, as shown in FIG. 7B, in the situation where the preceding vehicle follow-up control in which the own vehicle C1 follows the preceding vehicle C4 is being performed in the traveling lane DL, the driver operates the turn signal to overtake the preceding vehicle C4. In the case where the attention target vehicle C5 is detected in the overtaking lane PL, the target acceleration is maintained at the following target acceleration for tracking. That is, it is prohibited to switch the target acceleration to the overtaking target acceleration. As a result, the inter-vehicle distance between the preceding vehicle and the host vehicle is maintained without being shortened. In this case, the driver notices the presence of the vehicle to be watched because the display of the indicator 22 blinks in synchronization with the operation of the turn signal, and cancels the overtaking operation. Therefore, it is possible to realize the traveling of the vehicle in accordance with the driver's intention.

<Calculation of target acceleration for constant speed driving>
Next, the calculation of the target acceleration for constant speed traveling will be described. Based on the vehicle speed Vn detected by the vehicle speed sensor and the set vehicle speed Vset set by the driver using the ACC switch 13, the driving assistance ECU 10 calculates a constant speed target acceleration Aconst as shown in the following equation (3). * Is repeatedly calculated at a predetermined calculation cycle.
Aconst*=(Vset−Vn)×K3 (3)

Here, K3 is a constant speed traveling acceleration gain, and is set to a positive value according to the vehicle speed Vn. The constant-speed traveling acceleration gain may be set to a value that is smaller when the vehicle speed Vn is higher than when it is low. When the vehicle speed deviation (Vset-Vn) of the first term on the right side of the equation (3) is positive, the constant speed traveling target acceleration Aconst* that acts in the direction of accelerating the host vehicle is calculated, and the vehicle speed deviation (Vset-Vn). If is negative, the constant-speed traveling target acceleration Aconst* that acts in the direction of decelerating the host vehicle is calculated.

<Curve running target acceleration calculator>
The driving assistance ECU 10 repeatedly calculates a curve-traveling target acceleration Acurve*, which is a target acceleration when traveling on a curved road, at a predetermined calculation cycle. The drive assist ECU 10 uses the vehicle speed Vn detected by the vehicle speed sensor and the yaw rate Yaw detected by the yaw rate sensor to calculate the target for the curve travel according to the following equations (4), (4-1) and (4-2). Calculate the acceleration Acurve*.
Acurve*=(Vcurve-Vn)×K4 (4)

Here, Vcurve is an allowable speed that is allowed when traveling on a curve, and is calculated by the following equation (4-1). sqrt means a function for obtaining a square root value.
Vcurve=sqrt(R×Gcy) (4-1)

R is the estimated curve radius of the road at the position where the vehicle is traveling, and is calculated by the following equation (4-2). Kr is a conversion coefficient. As the estimated curve radius R, for example, the front camera sensor 11 can detect lane markers (white lines) on the left and right of the traveling lane, and the curve radius can be calculated from the line of the lane markers.
R=Kr×(Vn/Yaw) (4-2)
Further, Gcy is a lateral acceleration that is allowed in a curve running and is set in advance. K4 is a gain having a preset magnitude.

The lower limit value of the target acceleration Acurve* for curve running is set to zero, and when the calculation result is a negative value, the lower limit processing is set to zero.

<Final target acceleration>
The driving assistance ECU 10 selects the smallest value of the following target acceleration Afollow*, the constant speed target acceleration Aconst*, and the curve target acceleration Acurve*, and uses the selected value as the final target. Set to acceleration A*.
A*=min (Afollow*, Aconst*, Acurve*) (5)
Here, min means a function that selects the minimum value of the numerical values in parentheses.

<Calculation of required driving force>
The driving support ECU 10 calculates an acceleration deviation ΔA (=A*−An) which is a deviation between the target acceleration A* and the actual acceleration An that is the actual acceleration of the host vehicle, and the required drive is performed based on this acceleration deviation ΔA. Calculate the force F*. For example, the driving support ECU 10 adds the required driving force F*(n-1) one calculation cycle before to the value obtained by multiplying the acceleration deviation ΔA by the gain K5 as shown in the following equation (6). Is set to the required driving force F*.
F*=(A*-An)×K5+F*(n-1) (6)

The driving assistance ECU 10 calculates the required driving force F* at a predetermined calculation cycle, and supplies the calculated required driving force F* to the engine ECU 30 each time. As a result, the driving force is controlled so that the host vehicle accelerates (including deceleration) at the target acceleration A*. Therefore, the vehicle can be driven at an acceleration suitable for the preceding vehicle following control or the constant speed control. The actual acceleration An may be obtained by differentiating the vehicle speed Vn, or may be obtained by providing a longitudinal acceleration sensor (not shown) in the vehicle body and detecting the value from the longitudinal acceleration sensor. May be.

The engine ECU 30 is required to have a large braking force (negative driving force), and when the internal combustion engine 32 and a transmission (not shown) alone cannot meet the demand, the brake ECU 40 causes the hydraulic brake to generate the shortage. The requested braking force is transmitted to.

According to the vehicle driving assistance apparatus of the present embodiment described above, when a winker operation on the overtaking lane side is detected during execution of the preceding vehicle following control, another vehicle that the driver should be careful of is overtaken by the BSM system. It is determined whether or not it is detected in the lane (whether the indicator 22 is operating). If another vehicle that the driver should be careful of is detected in the overtaking lane (S14: No), the change of the target acceleration of the own vehicle to the overtaking target acceleration is stopped (S16). Therefore, the target acceleration is prevented from being unnecessarily increased. As a result, unnecessary acceleration when both ACC and BSM are performed is suppressed, and driving feeling can be improved.

Although the vehicle driving support apparatus according to the present embodiment has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

For example, a winker interlocking target acceleration request limiting routine may be carried out as shown in FIG. The driving assistance ECU 10 repeatedly executes the winker interlocking target acceleration request limiting routine (FIG. 8) at a predetermined calculation cycle. In step S21, the driving assistance ECU 10 determines whether or not the turn signal interlocking target acceleration request is being executed. That is, the driving assistance ECU 10 determines whether or not the target acceleration is set to the overtaking target acceleration. When the winker interlocking target acceleration request is not being executed (S21: No), the driving assistance ECU 10 once ends the winker interlocking target acceleration request limiting routine.

On the other hand, when the turn signal interlocking target acceleration request is being executed (S21: Yes), the driving support ECU 10 determines whether or not the indicator 22 of the BSM on the overtaking lane side is operating in the subsequent step S22. When the indicator 22 on the overtaking lane side is operating (S22: Yes), the driving support ECU 10 cancels the turn signal interlocking target acceleration request in step S23. Therefore, the target acceleration is switched from the overtaking target acceleration to the following target acceleration.

On the other hand, when the indicator 22 on the overtaking lane side is not operating (S22: No), the driving assistance ECU 10 once ends the turn signal interlocking target acceleration request limiting routine. Therefore, the execution of the blinker interlocking target acceleration request is continued. That is, the inter-vehicle distance between the preceding vehicle and the host vehicle is shortened by the overtaking target acceleration.

With this modification, the same effect as that of the embodiment can be obtained.

10... Driving support ECU, 11... Front camera sensor, 12... Front radar sensor, 13... ACC switch, 20... Blind spot monitor ECU, 21L, 21R... Left rear radar sensor, 22R, 22L... Indicator, 30... Engine ECU, 31... Engine actuator, 32... Internal combustion engine, 40... Brake ECU, 41... Brake actuator, 42... Friction brake mechanism, 50... Meter ECU, 51... Indicator, 52... Winker, 60... Vehicle state sensor, 70... Driving operation State sensor, Afollow... Target acceleration for following, Afollow1... Target acceleration for following acceleration, Afollow2... Target acceleration for following deceleration, C1... Own vehicle, C2, C3, C5... Target vehicle, C4... Preceding vehicle, DL... Driving lane, PL... Overtaking lane, Ka... Acceleration side gain, Ka0... Follow-up acceleration gain, Ka1... Overtaking acceleration gain.

Claims (1)

Preceding vehicle follow-up control, which is control for calculating a target acceleration for causing the subject vehicle to follow the preceding vehicle while keeping the inter-vehicle distance from the subject vehicle to the preceding vehicle at a predetermined distance, and causing the subject vehicle to travel at the target acceleration When performing a turn signal operation on the overtaking lane side while performing the preceding vehicle following control, the target acceleration of the host vehicle is higher than the target acceleration for following the preceding vehicle. A preceding vehicle following control means for changing to a target acceleration for overtaking,
Blind spot monitoring means that monitors another vehicle traveling behind the vehicle in the adjacent lane adjacent to the lane of the own vehicle and alerts the driver when the other vehicle that the driver should be aware of is detected. In a vehicle driving assistance device including
During the execution of the preceding vehicle following control, it is determined by the blind spot monitor means whether another vehicle that the driver should be careful of is detected in the overtaking lane, and the other vehicle that the driver should be careful of is in the overtaking lane. A vehicle driving assistance apparatus including an acceleration limiting unit that prevents the target acceleration of the host vehicle from being set to the target acceleration for overtaking when detected.

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