JP5617198B2 - Preceding vehicle following control device and preceding vehicle following control method - Google Patents

Description

  The present invention relates to a preceding vehicle following control device and a preceding vehicle following control method.

  In the preceding vehicle follow-up control device described in Patent Document 1, when the driver performs a brake operation during the follow-up control, the control of the actuator corresponding to the target inter-vehicle distance is stopped and switched to the actuator control accompanying the brake operation. Thereafter, when the brake operation is finished, the control of the actuator accompanying the brake operation is released, and the inter-vehicle distance at the end of the brake operation is set as the target inter-vehicle distance.

JP-A-10-318209

  In the above prior art, when the driver performs the brake operation, the actuator is controlled in accordance with the brake operation. Therefore, the vehicle is decelerated according to the brake operation amount by cutting off the fuel supply to the engine. In addition to this, deceleration due to engine braking acts. For this reason, the vehicle speed of the own vehicle greatly decreases with respect to the vehicle speed of the preceding vehicle, and at the end of the brake operation, the acceleration time necessary for increasing the decreased vehicle speed to the vehicle speed of the preceding vehicle becomes longer. That is, the conventional preceding vehicle tracking control device has a problem that the driver feels uncomfortable because the vehicle behavior change accompanying the change of the target inter-vehicle distance is large.

  In the present invention, when a brake operation amount equal to or less than a predetermined amount is detected during the follow-up control, a deceleration equal to or less than the deceleration due to the engine brake is generated.

  Therefore, in the present invention, when the driver performs a braking operation of a predetermined amount or less, the vehicle only generates a deceleration that is less than the deceleration by the engine brake. Acceleration time can be shortened. As a result, it is possible to suppress a change in vehicle behavior that accompanies a change in the target inter-vehicle distance due to the driver's braking operation, and to reduce the uncomfortable feeling given to the driver.

It is a block diagram which shows the structure of the preceding vehicle follow-up control apparatus of Example 1. FIG. 3 is a flowchart illustrating a flow of target inter-vehicle distance change control processing according to the first embodiment. FIG. 3 is a relationship diagram of deceleration with respect to a brake operation amount according to the first embodiment. 3 is a time chart of deceleration and vehicle speed showing the operation of the first embodiment. FIG. 6 is a relationship diagram of deceleration with respect to a brake operation amount according to a second embodiment. FIG. 6 is a relationship diagram of deceleration with respect to a brake operation amount according to a third embodiment. FIG. 10 is a block diagram illustrating a configuration of a preceding vehicle follow-up control device of a fourth embodiment. 12 is a flowchart illustrating a flow of target inter-vehicle distance change control processing according to a fourth embodiment. 12 is a flowchart illustrating a flow of an inter-vehicle distance control process according to a fourth embodiment. 10 is a target inter-vehicle distance increase amount map according to the brake operation amount of the fourth embodiment.

First, the configuration will be described.
FIG. 1 is a block diagram illustrating a configuration of a preceding vehicle follow-up control device according to the first embodiment. The preceding vehicle follow-up control device according to the first embodiment includes a vehicle speed sensor 1, a preceding vehicle detection sensor 2, and an accelerator operation detection sensor 3. A brake operation amount detection sensor (brake operation amount detection means) 4, a follow-up control device (follow-up control means) 5, a brake actuator 7, a throttle actuator 8, a brake device 9, a throttle 10, and a first buzzer (Notification means) 11 and a second buzzer (notification means) 12 are provided.

The vehicle speed sensor 1 detects the vehicle speed of the host vehicle.
The preceding vehicle detection sensor 2 detects the presence or absence of a preceding vehicle existing ahead of the host vehicle, and detects the inter-vehicle distance from the preceding vehicle and the vehicle speed of the preceding vehicle when the preceding vehicle exists. As the preceding vehicle detection sensor 2, for example, a radar that detects a preceding vehicle based on a reflected wave with respect to an outgoing wave, such as a scanning laser radar or a millimeter wave radar, or a preceding vehicle based on an image obtained by imaging the front of the vehicle A camera can be used.
The accelerator operation detection sensor 3 detects whether or not the accelerator pedal is operated by the driver. As the accelerator operation detection sensor 3, an accelerator switch that is turned ON with a predetermined accelerator pedal operation amount can be used.
The brake operation amount detection sensor 4 detects a driver's brake pedal operation amount (hereinafter, brake operation amount). As the brake operation amount detection sensor 4, a stroke sensor that detects the stroke amount of the brake pedal can be used.

The follow-up control device 5 includes a travel control unit 6a and a deceleration command value creation unit 6b.
When the preceding vehicle is detected by the preceding vehicle detection sensor 2, the traveling control unit 6a detects the vehicle speed of the host vehicle detected by the vehicle speed sensor 1, the distance from the preceding vehicle detected by the preceding vehicle detection sensor 2, and the preceding vehicle. Based on this vehicle speed, follow-up control is executed to output commands to the brake actuator 7 and the throttle actuator 8 so that the inter-vehicle distance with the preceding vehicle coincides with a predetermined target inter-vehicle distance. On the other hand, when the preceding vehicle is not detected, constant speed running control is performed to output commands to the brake actuator 7 and the throttle actuator 8 so that the host vehicle runs at a constant speed at the set vehicle speed set by the driver. The follow-up control device 5 cancels (ends) the follow-up control or the constant speed travel when the accelerator operation detection sensor 3 detects the accelerator operation during the follow-up control or the constant speed travel control.

In the first embodiment, the driver preselects one of a plurality of preset target inter-vehicle times (for example, three stages of target inter-vehicle times of H, M, and L) by switch operation, and automatically selects the target inter-vehicle time at the selected target inter-vehicle time. The target inter-vehicle distance is set by multiplying the vehicle speed. In the following description, the target inter-vehicle distance determined by the driver is referred to as a predetermined target inter-vehicle time.
In the first embodiment, whether or not to perform the follow-up control and the constant speed traveling control can be selected by, for example, a driver's switch operation.

  When the brake operation amount detected by the brake operation amount detection sensor 4 is equal to or less than a predetermined amount during the follow-up control, the travel control unit 6a temporarily stops the generation of the deceleration according to the predetermined target inter-vehicle distance, Drive commands are output to the brake actuator 7 and the throttle actuator 8 in accordance with the deceleration command value created by the deceleration command value creation unit 6b. Here, in the first embodiment, the predetermined amount is the maximum brake operation amount within the range of the play area of the brake pedal. Here, the play area of the brake pedal refers to an area of the brake operation amount where the brake master cylinder pressure does not rise with respect to the brake operation amount.

  The travel control unit 6a resumes the follow-up control with the inter-vehicle distance at the end of the brake operation as a new target inter-vehicle distance when a predetermined follow-up resumption condition to be described later is established, and when the follow-up resume condition is not established, The tracking control is canceled (terminated), a notification sound is emitted by the second buzzer 12, and then the control shifts to constant speed traveling control. On the other hand, when the brake operation amount exceeds a predetermined amount, the follow-up control is canceled (terminated) and a notification sound is emitted from the first buzzer 11. Here, it is assumed that the first buzzer 11 and the second buzzer 12 emit different notification sounds.

When the brake operation amount detected by the brake operation amount detection sensor 4 is equal to or less than a predetermined amount during the follow-up control, the deceleration command value creation unit 6b reduces the vehicle deceleration to the deceleration caused by the engine brake (reduction when the accelerator is not operated). A deceleration command value having a predetermined deceleration below (velocity) is created and output to the traveling control unit 6a.
The brake actuator 7 increases or decreases each wheel cylinder pressure of the brake device 9 based on a drive command from the tracking control device 5 regardless of whether or not a brake operation is performed.
The brake device 9 is a normal hydraulic brake device that increases the wheel cylinder pressure provided on each wheel by the master cylinder pressure increased according to the brake operation amount. Hereinafter, the deceleration of the vehicle generated by the braking force according to the brake operation amount not using the brake actuator 7 is referred to as a normal deceleration.
The throttle actuator 9 controls the opening / closing amount of the throttle 10 that adjusts the intake air amount to the engine based on the drive command from the tracking control device 5.

[Target inter-vehicle distance change control process]
The follow-up control device 5 according to the first embodiment executes the following control in order to realize suppression of a change in vehicle behavior accompanying a change in the target inter-vehicle distance by a driver's brake operation, which is a target of the present invention.
FIG. 2 is a flowchart showing the flow of the target inter-vehicle distance change control process according to the first embodiment. Each step will be described below. This process is repeatedly executed at a predetermined calculation cycle from the start to the end of the follow-up control.

In step S1, the driver's brake operation is determined based on whether or not the brake operation amount detected by the brake operation amount detection sensor 4 is greater than zero. If yes, then go to step S2, if no, go to return.
In step S2, it is determined whether or not the brake operation amount detected by the brake operation amount detection sensor 4 is equal to or less than a predetermined amount. If YES, the process proceeds to step S3. If NO, the process proceeds to step S4. As described above, the predetermined amount is the maximum brake operation amount in the range of the play area of the brake pedal.

In step S3, deceleration generation is temporarily stopped according to a predetermined target inter-vehicle distance, and a deceleration command value for generating a predetermined deceleration equal to or lower than the deceleration by the engine brake is output to the brake actuator 7, The process proceeds to step S5. The deceleration due to the engine brake is the engine brake calculated from the engine speed at that time (the time when the brake operation of the operation amount equal to or less than the predetermined amount is made), the transmission reduction ratio, etc., that is, the engine at that time This is the deceleration due to the engine braking force generated when the engine fuel cut is performed at the number of revolutions of the engine and the reduction ratio of the transmission.
In step S4, the deceleration command value output to the brake actuator 7 is set to zero, thereby generating a normal deceleration according to the brake operation amount, and the process proceeds to step S14.
In step S5, the end of the brake operation is determined based on whether or not the brake operation amount detected by the brake operation amount detection sensor 4 is zero. If YES, the process proceeds to step S6. If NO, the process proceeds to step S2.

In step S6, it is determined whether or not a follow-up resumption condition for resuming the follow-up control temporarily stopped in step S3 at the end of the brake operation is satisfied. If YES, the process proceeds to step S7. If NO, the process proceeds to step S9. Here, when all of the following three conditions are satisfied, it is determined that the follow-up restart condition is satisfied.
Condition 1: The inter-vehicle distance from the preceding vehicle is within a predetermined setting range.
Condition 2: The relative speed with the preceding vehicle is close to zero.
Condition 3: The preceding vehicle is the same vehicle before and after the brake operation.
In step S7, the target inter-vehicle distance is changed to the inter-vehicle distance detected by the preceding vehicle detection sensor 2 at the end of the brake operation, that is, immediately after YES is determined in step S5, and the process proceeds to step S8.
In step S8, the follow-up control (generation of deceleration according to the target inter-vehicle distance) is resumed, and the process proceeds to return.

In step S9, the follow-up control is canceled (terminated), and the process proceeds to step S10.
In step S10, the second buzzer 12 generates a notification sound to notify the driver that the follow-up control is to be shifted to the constant speed travel control, and the process proceeds to step S11.
In step S11, the vehicle speed of the host vehicle at the end of the brake operation is set as the vehicle speed set for constant speed travel control, and the process proceeds to step S12.
In step S12, constant speed traveling control is performed based on the set vehicle speed set in step S11, and the process proceeds to return.
In step S13, the follow-up control is canceled and the process proceeds to step S14.
In step S14, the first buzzer 11 generates a notification sound to inform the driver that the follow-up control has ended, and the process proceeds to return.

Next, the operation will be described.
In the conventional preceding vehicle tracking control device, when the driver performs a brake operation during the tracking control, the inter-vehicle distance desired by the driver is realized by setting the inter-vehicle distance at the end of the braking operation as a new target inter-vehicle distance. . At this time, in the conventional hydraulic brake device, as shown in FIG. 3, when the brake operation amount is within the range of the play area of the brake pedal, the master cylinder pressure does not rise, so no deceleration occurs. In addition, the brake switch that detects the driver's brake operation is normally set to turn on at a brake operation amount that actually causes deceleration due to the hydraulic brake, that is, a brake operation amount that exceeds the play area of the brake pedal. Therefore, there is no deceleration caused by engine braking.

  Therefore, in the prior art, in order for the driver to increase the inter-vehicle distance, it is necessary to depress the brake pedal beyond the play area of the brake pedal. However, in the prior art, when the brake operation of the driver is detected, the actuator control associated with the brake operation is executed, and the actuator control according to the target inter-vehicle distance is stopped. At this time, since the driver is not stepping on the accelerator pedal, deceleration due to engine braking occurs as the engine fuel is cut.

  In other words, in the prior art, when the driver performs a brake operation during the follow-up control, a deceleration by the hydraulic brake and a deceleration by the engine brake act on the vehicle according to the amount of the brake operation by the driver. For this reason, as shown in FIG. 4, the vehicle speed of the own vehicle greatly decreases with respect to the vehicle speed of the preceding vehicle, and at the end of the driver's braking operation, a longer acceleration time is taken to increase the decreased vehicle speed to the vehicle speed of the preceding vehicle. . Therefore, in the conventional preceding vehicle follow-up control device, the vehicle behavior change accompanying the change in the target inter-vehicle distance due to the driver's brake operation is large, and the driver feels uncomfortable. Further, since the deceleration at the time of brake operation is large, the response delay until the transition from the deceleration state to the acceleration state becomes large when the follow-up control is resumed.

  On the other hand, in the follow-up control device 5 of the first embodiment, when a brake operation amount equal to or less than a predetermined amount is detected during the follow-up control, as shown in FIG. 3, the deceleration generated when the brake and the accelerator are not operated, Then, a predetermined deceleration below the deceleration by the engine brake is generated (step S1 → step S2 → step S3). Therefore, as shown in FIG. 4, the vehicle speed difference between the host vehicle and the preceding vehicle when the driver decelerates by braking and increases the inter-vehicle distance can be made smaller than before. For this reason, when tracking control is resumed in step S8, the time required for acceleration can be shortened. Further, since the deceleration at the end of the brake operation can be kept lower than before, the vehicle can be promptly shifted from the deceleration state to the acceleration state when the follow-up control is resumed.

  In the deceleration process of step S3, the brake operation amount that generates a predetermined deceleration equal to or less than the deceleration by the engine brake is set within the range of the brake pedal play area, that is, in the brake device 9, the hydraulic brake according to the brake operation amount It is set to a predetermined amount that does not occur. When the amount of brake operation is within the range of the play area of the brake pedal, the brake pedal is lighter than when it is outside the range of the play area. There is an advantage that it is easy to grasp the brake operation amount that generates the predetermined deceleration.

In the first embodiment, when a brake operation amount exceeding a predetermined amount is detected in step S2, a normal deceleration according to the brake operation amount is generated in step S4. Therefore, the driver decelerates even during follow-up control. If there is an intention, the vehicle can be decelerated by a deceleration according to the amount of brake operation, as in normal driving.
In step S13 following step S4, the follow-up control is canceled. For this reason, the driver can end the follow-up control with one brake operation. In the conventional preceding vehicle follow-up control device, the driver manually operates the switch to finish the follow-up control. However, in the preceding vehicle follow-up control device according to the first embodiment, the manual operation is saved and the line-of-sight direction is not changed. Follow-up control can be canceled.

Here, in the above prior art, when the follow-up control is continued even if the driver performs the brake operation, the deceleration due to the engine brake does not occur, so the deceleration at the end of the brake operation can be reduced. However, if the follow-up control is continued during the brake operation, when a vehicle interrupt occurs between the own vehicle and the preceding vehicle during the brake operation, the follow-up control is activated with the interrupting vehicle as the preceding vehicle, and the vehicle speed of the interrupting vehicle is automatically adjusted. Even if it is equal to the vehicle speed, the host vehicle decelerates rapidly in order to maintain the target inter-vehicle distance.
On the other hand, in the follow-up control device 5 according to the first embodiment, even when the above-described interruption occurs, when the brake operation amount is equal to or less than a predetermined amount, a predetermined target inter-vehicle distance is used. Since the deceleration is temporarily stopped and a predetermined deceleration equal to or lower than the deceleration by the engine brake is generated, the own vehicle does not decelerate suddenly. When the vehicle speed of the interrupting vehicle is lower than the vehicle speed of the own vehicle, the normal deceleration according to the brake operation amount can be generated by depressing the brake pedal more than a predetermined amount. Is never too close.

  In Example 1, when a brake operation amount equal to or less than a predetermined amount is detected in Step S2, it is determined that the brake operation is completed in Step S5, and then it is determined in Step S6 that the follow-up restart condition is satisfied. In step S7, the target inter-vehicle distance is changed, and the tracking control is restarted in step S8. Here, the follow-up restart condition is satisfied when the inter-vehicle distance from the preceding vehicle is within a predetermined setting range, the relative speed with the preceding vehicle is close to zero, and the preceding vehicle is the same vehicle before and after the brake operation. It is determined that

For example, at the end of the brake operation, if tracking control is restarted when the preceding vehicle is located farther than the preset setting range or when the vehicle speed difference between the preceding vehicle and the host vehicle is large, the vehicle accelerates for a long time. It is necessary to make the driver feel uncomfortable. Further, when an interruption occurs between the preceding vehicle and the host vehicle during the brake operation, the target inter-vehicle distance for the interruption vehicle may be set too short.
Therefore, when all of the above three conditions are not satisfied, canceling the tracking control can prevent resumption of tracking the preceding vehicle that should not be tracked.

  If the tracking restart condition is not satisfied in step S6, the tracking control is canceled in step S9, the vehicle speed at the end of the brake operation is set as the set vehicle speed in step S11, and the constant speed traveling control is performed in which the vehicle is driven at a constant speed in step S12. carry out. For this reason, the driver can switch from the follow-up control to the constant speed traveling control by only one brake operation. For example, if the vehicle speed of the preceding vehicle in the follow-up control is felt higher than the driver's preferred vehicle speed for the driving environment and you want to cancel the follow-up control, or if the preceding vehicle is traveling beyond the speed limit Since the driver performs a brake operation of a predetermined amount or less, the condition 2 for determining the follow-up resumption condition is not satisfied, so that the vehicle speed at the end of the brake operation can be shifted to the constant speed traveling control with the set vehicle speed.

  In the first embodiment, the notification sound is emitted from the second buzzer 12 in step S10 before shifting to constant speed traveling control in step S12, so that the driver can be informed of shifting to constant speed traveling control. In addition, after the tracking control is canceled in step S13, a notification sound is generated by the first buzzer 11 in step S14, so that the driver can be notified of the end of the tracking control.

Next, the effect will be described.
The preceding vehicle follow-up control device according to the first embodiment has the following effects.
(1) Brake operation amount detection sensor 4 that detects the brake operation amount of the driver and tracking control that generates deceleration below the deceleration due to engine braking when a brake operation amount below a predetermined amount is detected during tracking control And a device 5. Thereby, the vehicle behavior change accompanying the change of the target inter-vehicle distance by the driver's brake operation can be suppressed, and the uncomfortable feeling given to the driver can be reduced.

  (2) Since the predetermined amount is within the range of the play area of the brake pedal, the driver can grasp the brake operation amount that generates a predetermined deceleration equal to or less than the deceleration due to the engine brake due to the difference in pedaling force.

  (3) The follow-up control device 5 generates a normal deceleration according to the brake operation amount when a brake operation amount exceeding a predetermined amount is detected during the follow-up control. When there is an intention to decelerate, the vehicle can be decelerated by a deceleration according to the amount of brake operation, as in normal driving.

  (4) The tracking control device 5 cancels the tracking control without changing the line-of-sight direction by eliminating the manual operation in order to terminate the tracking control when a brake operation amount exceeding a predetermined amount is detected during the tracking control. it can.

  (5) The follow-up control device 5 detects the amount of brake operation below a predetermined amount during the follow-up control, and when the brake operation is finished thereafter, the following distance is within the set range determined in advance. When all of the three conditions of the speed close to zero or the preceding vehicle being the same vehicle before and after the brake operation are satisfied, the follow-up control is resumed with the inter-vehicle distance at the end of the brake operation as the target inter-vehicle distance. As a result, it is possible to prevent resumption of following the preceding vehicle that should not be followed, and to suppress the rapid acceleration / deceleration.

  (6) When the follow-up restart condition is not satisfied, the follow-up control device 5 performs constant-speed running control in which the vehicle runs at a constant speed with the vehicle speed at the end of the brake operation as the set vehicle speed. Even if it exists, when constant speed travel is desired, it is possible to switch from follow-up control to constant speed travel control with only one brake operation.

  (7) Since the second buzzer 12 for notifying the transition from the follow-up control to the constant speed running control and the first buzzer 11 for notifying the driver of the end of the follow-up control are provided, the control details executed by the follow-up control device 5 are informed to the driver. Can do.

  (8) Follow-up control that maintains the inter-vehicle distance between the host vehicle and the preceding vehicle at a predetermined target inter-vehicle distance, and changes the target inter-vehicle distance when the driver performs a brake operation during the follow-up control. In the follow-up control method, when a brake operation amount equal to or less than a predetermined amount is detected during the follow-up control, a deceleration equal to or less than the deceleration caused by the engine brake is generated. Thereby, the vehicle behavior change accompanying the change of the target inter-vehicle distance by the driver's brake operation can be suppressed, and the uncomfortable feeling given to the driver can be reduced.

The preceding vehicle follow-up control device of the second embodiment is an example in which the deceleration is increased as the brake operation amount is larger when the brake operation amount is equal to or less than a predetermined amount.
First, the configuration will be described. The parts common to the first embodiment are denoted by the same names and the same reference numerals, and illustration and description thereof are omitted.
[Target inter-vehicle distance change control process]
The target inter-vehicle distance change control process of the second embodiment is different from the target inter-vehicle distance change control process of the first embodiment shown in FIG. 2 only in the content of the deceleration process in step S3, and will be described with reference to FIG.
In step S3, the deceleration generation according to a predetermined target inter-vehicle distance is temporarily stopped, and the deceleration is increased as the brake operation amount detected by the brake operation amount detection sensor 4 is increased with the deceleration by the engine brake as the upper limit. Deceleration control is performed to output a deceleration command value to be increased to the brake actuator 7, and the process proceeds to step S5.

Next, the operation will be described.
FIG. 5 is a relationship diagram of the deceleration with respect to the brake operation amount in the second embodiment. In the second embodiment, when the brake operation amount of the driver is equal to or less than a predetermined amount, The increase increases the deceleration. For this reason, when resetting the target inter-vehicle distance, the driver can decelerate the vehicle at a desired deceleration, and the controllability of the vehicle can be improved compared to the first embodiment in which the deceleration is constant. .

Next, the effect will be described.
In the preceding vehicle follow-up control device of the second embodiment, in addition to the effects (1) to (8) of the first embodiment, the following effects can be obtained.
(9) When the brake operation amount equal to or less than the predetermined amount is detected during the follow-up control, the tracking control device 5 increases the deceleration as the brake operation amount increases, so the vehicle is driven at a deceleration according to the driver's preference. It can be decelerated.

The preceding vehicle follow-up control device according to the third embodiment is an example that generates acceleration / deceleration between the current acceleration and the deceleration at a predetermined amount when the host vehicle is accelerating when the driver starts the braking operation.
First, the configuration will be described. The parts common to the first embodiment are denoted by the same names and the same reference numerals, and illustration and description thereof are omitted.
[Target inter-vehicle distance change control process]
The target inter-vehicle distance change control process of the third embodiment is different from the target inter-vehicle distance change control process of the first embodiment shown in FIG. 2 only in the content of the deceleration process in step S3, and will be described with reference to FIG.
In step S3, the deceleration generation according to a predetermined target inter-vehicle distance is temporarily stopped, and the deceleration is increased as the brake operation amount detected by the brake operation amount detection sensor 4 is increased with the deceleration by the engine brake as the upper limit. Deceleration control is performed to output a deceleration command value to be increased to the brake actuator 7, and the process proceeds to step S5. At this time, if the host vehicle is accelerating, the current acceleration is the starting point, and the deceleration command value that generates acceleration or deceleration that increases in the deceleration direction as the brake operation amount increases with the deceleration by engine brake as the upper limit. Is output. That is, the difference between the current acceleration (positive acceleration) and the deceleration due to engine braking (negative acceleration) is divided by the predetermined amount to calculate the change in acceleration relative to the brake operation amount. An acceleration (deceleration) obtained by multiplying the detected brake operation amount by the acceleration change amount is generated.

Next, the operation will be described.
FIG. 6 is a relationship diagram of deceleration with respect to the brake operation amount in the third embodiment.
For example, when the driver depresses the brake pedal in order to reset the target inter-vehicle distance while the acceleration of A in FIG. 6 is generated in the vehicle, in Example 3, the acceleration gradually decreases to zero starting from A. Approaches and then the deceleration increases. In the conventional preceding vehicle follow-up control device, when the brake operation amount reaches a predetermined amount, the vehicle behavior changes abruptly by performing deceleration with a deceleration command value far from the vehicle acceleration. On the other hand, in Example 3, since it changes smoothly from the present acceleration to the deceleration by an engine brake, the sudden change of a vehicle behavior can be suppressed.

Next, the effect will be described.
The preceding vehicle follow-up control device according to the third embodiment has the following effects in addition to the effects (1) to (8) of the first embodiment and the effect (9) of the second embodiment.
(10) When the vehicle is accelerating when the driver starts the brake operation, the tracking control device 5 is between the current acceleration and the deceleration at the predetermined amount, and the deceleration direction increases as the brake operation amount increases. Therefore, a sudden change in vehicle behavior can be suppressed.

First, the configuration will be described. The parts common to those in the first embodiment are denoted by the same names and the same reference numerals, and the description thereof is omitted.
FIG. 7 is a block diagram illustrating the configuration of the preceding vehicle follow-up control device according to the fourth embodiment. The follow-up control device 5 according to the fourth embodiment replaces the deceleration command value creation unit 6b according to the first embodiment with an inter-vehicle distance changing unit. 6c.
The inter-vehicle distance changing unit 6c calculates a target inter-vehicle command value that increases the inter-vehicle distance as the brake operation amount increases when the brake operation amount detected by the brake operation amount detection sensor 4 is equal to or less than the predetermined amount during the follow-up control. To do.
When the brake operation amount detected by the brake operation amount detection sensor 4 is equal to or less than a predetermined amount during the follow-up control, the travel control unit 6a temporarily stops the generation of the deceleration according to the predetermined target inter-vehicle distance, Drive commands are output to the brake actuator 7 and the throttle actuator 8 according to the target inter-vehicle command value calculated by the inter-vehicle distance changing unit 6c.

[Target inter-vehicle distance change control process]
FIG. 8 is a flowchart showing the flow of the target inter-vehicle distance change control process of the fourth embodiment, and is the same as that of the first embodiment shown in FIG. 2 except for step S21.
In step S21, deceleration generation according to a predetermined target inter-vehicle distance is temporarily stopped, inter-vehicle distance control is performed, and the process proceeds to step S5. Details of the inter-vehicle distance control are shown in FIG.

[Vehicle distance control processing]
FIG. 9 is a flowchart illustrating the flow of the inter-vehicle distance control process according to the fourth embodiment. Each step will be described below.
In step S41, the brake operation amount detected by the brake operation amount detection sensor 4 is compared with the previous value (the brake operation amount detected in the previous calculation cycle), and the brake depression direction is the positive direction (including zero). It is determined whether or not. If YES, the process proceeds to step S42, and if NO, this control is terminated.

In step S42, the target inter-vehicle distance is calculated, and the process proceeds to step S43. In the first embodiment, the target inter-vehicle distance is calculated by adding the target inter-vehicle distance increase amount corresponding to the brake operation amount to the predetermined target inter-vehicle distance. FIG. 10 is a target inter-vehicle distance increase amount map according to the brake operation amount of the fourth embodiment. The target inter-vehicle distance increase amount has a characteristic that increases as the brake operation amount increases.
In step S43, inter-vehicle servo control for servo-controlling the brake actuator 7 based on the target inter-vehicle command value corresponding to the target inter-vehicle distance calculated in step S42 is executed, and this control is terminated.

Next, the operation will be described.
In the fourth embodiment, during the follow-up control, when the brake pedal is operated at a predetermined amount or less in the stepping direction, the inter-vehicle distance control is executed so that the inter-vehicle distance increases as the brake operation amount increases. Even in a normal driving scene where the preceding vehicle tracking control device is not used, when the distance between the preceding vehicle and the preceding vehicle is increased, the driver performs a brake operation to decelerate the vehicle. Therefore, in Example 4 in which control is performed so that the inter-vehicle distance is increased by depressing the brake, there is little discomfort given to the driver when changing the target inter-vehicle distance. Further, it is possible to prevent operation mistakes and line-of-sight movement that may occur when the inter-vehicle distance is increased by a driver's switch operation.

Next, the effect will be described.
The preceding vehicle follow-up control device of the fourth embodiment has the following effects in addition to the effects (1) to (8) of the first embodiment and the effect (9) of the second embodiment.
(11) The tracking control device 5 calculates the target inter-vehicle distance that increases the inter-vehicle distance as the brake operation amount increases, and executes the inter-vehicle distance control with the preceding vehicle, so the driver does not confuse the target inter-vehicle distance. In addition to being able to adjust, it is possible to prevent operation errors and line-of-sight movements that may occur when adjusting the inter-vehicle distance by switch operation.

The preceding vehicle follow-up control device according to the fifth embodiment includes a deceleration command value corresponding to a brake operation amount equal to or less than a predetermined amount and a deceleration command value that maintains a predetermined target inter-vehicle distance, whichever is larger in the deceleration direction. This is an example of decelerating the vehicle based on the value.
First, the configuration will be described. The parts common to the first embodiment are denoted by the same names and the same reference numerals, and illustration and description thereof are omitted.

[Target inter-vehicle distance change control process]
The target inter-vehicle distance change control process of the fifth embodiment is different from the target inter-vehicle distance change control process of the first embodiment shown in FIG. 2 only in the content of the target inter-vehicle distance in step S7, and will be described with reference to FIG.
In step S7, when the brake operation ends, that is, immediately after the determination in step S5 is YES, the deceleration command value when the preceding vehicle detection sensor 2 detects the inter-vehicle distance as the target inter-vehicle distance and a predetermined target inter-vehicle distance The deceleration command value that maintains the distance is compared, and the target inter-vehicle distance corresponding to the large deceleration command value is set as the new target inter-vehicle distance, and the process proceeds to step S8.

Next, the operation will be described.
In the first embodiment, the inter-vehicle distance at the end of the brake operation is set as the target inter-vehicle distance, and the brake actuator 7 is driven based on the deceleration command value that realizes the target inter-vehicle distance. For this reason, for example, when the driver is operating the brake pedal at a predetermined amount or less in order to increase the inter-vehicle distance with the preceding vehicle, there is a possibility that the preceding vehicle may be excessively approached when the preceding vehicle suddenly decelerates. .
Thus, in the fifth embodiment, when the deceleration command value for maintaining the predetermined target inter-vehicle distance is larger than the deceleration command value for adjusting the inter-vehicle distance, the predetermined target inter-vehicle distance is set. By decelerating the vehicle based on the deceleration command value to be maintained, it is possible to avoid sudden approach due to sudden deceleration of the preceding vehicle.

Next, the effect will be described.
In the preceding vehicle follow-up control device of the fifth embodiment, in addition to the effects (1) to (8) of the first embodiment, the following effects can be obtained.
(12) The tracking control device 5 sets the deceleration command value that is larger in the deceleration direction among the deceleration command value corresponding to the brake operation amount equal to or less than the predetermined amount and the deceleration command value that maintains a predetermined target inter-vehicle distance. Since the vehicle is decelerated based on this, excessive approach with the preceding vehicle due to sudden deceleration of the preceding vehicle can be suppressed.

(Other examples)
The best mode for carrying out the present invention has been described above based on the embodiments. However, the specific configuration of the present invention is not limited to the embodiments and is within the scope of the invention. Any design changes are included in the present invention.
For example, in the embodiment, the example in which the brake operation amount for generating the deceleration equal to or lower than the deceleration due to the engine brake is set within the range of the brake pedal play area may be out of the range of the brake pedal play area. . In other words, the brake operation amount that generates a deceleration equal to or lower than the deceleration by the engine brake during the preceding vehicle following control is controlled as a value larger than the range of the brake pedal play area at normal time (when the preceding vehicle following control is not being performed). May be performed.

In the embodiment, an example in which it is determined that the follow-up restart condition is satisfied when all three conditions are satisfied and the follow-up control is resumed is shown. However, any one or two of the three conditions is set. When satisfied, it may be determined that the following resumption condition is satisfied.
Further, in the embodiment, an example is shown in which the driver can select one of a plurality of target inter-vehicle times. However, one target inter-vehicle time is determined in advance, and the vehicle speed of the host vehicle or the preceding vehicle is set as the target inter-vehicle time. The target inter-vehicle distance may be obtained by multiplication.

1 Vehicle speed sensor
2 Leading vehicle detection sensor
3 Accelerator operation detection sensor
4 Brake operation amount detection sensor (Brake operation amount detection means)
5 Tracking control device (tracking control means)
6a Travel controller
6b Deceleration command value generator
6c Inter-vehicle distance changing section
7 Brake actuator
8 Throttle actuator
9 Brake device
10 throttle
11 First buzzer (notification means)
12 Second buzzer (notification means)

Claims (7)

A throttle actuator that adjusts the amount of intake air into the engine;
A brake device that applies a braking force to each wheel by increasing the wheel cylinder pressure of each wheel by the master cylinder pressure increased according to the brake operation amount of the driver;
A brake actuator capable of increasing or decreasing each wheel cylinder pressure of the brake device independently of the brake operation;
Inter-vehicle distance detection means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle;
The following distance detected by the inter-vehicle distance detecting means by driving the throttle actuator and the brake actuator so as to match the target following a predetermined distance by controlling the longitudinal force of the vehicle, follow with respect to the preceding vehicle Follow-up control means for performing control ,
In the preceding vehicle following control device having
Brake operation amount detection means for detecting the brake operation amount of the driver is provided,
The brake device has a brake pedal play area that is an area of a brake operation amount in which a master cylinder pressure does not rise with respect to a brake operation amount;
The follow-up control means includes
When a brake operation amount exceeding the maximum brake operation amount in the range of the play area is detected during the tracking control, the tracking control is terminated,
If the maximum amount of brake operation following brake operation amount in the range of the play area during the follow-up control is detected, the brake operation amount temporarily stop the deceleration generated in accordance with the target inter-vehicle distance is detected The brake actuator and the throttle actuator are driven so as to generate a deceleration equal to or less than the deceleration when the engine braking force is generated at this time , and at this time , the deceleration increases as the brake operation amount increases , driver when the brake operation start time on the vehicle is accelerating, to generate acceleration speed between the deceleration when the current acceleration of the maximum amount of brake operation in the range of the play area, the braking operation earlier but characterized that you resume the follow-up control of the vehicle-to-vehicle distance at the end of the braking operation as a new target inter-vehicle distance when you quit Car cruise control system. In the preceding vehicle follow-up control device according to claim 1,
The preceding vehicle follow-up control device calculates a target inter-vehicle distance that increases the inter-vehicle distance as the brake operation amount increases, and executes inter-vehicle distance control with the preceding vehicle. In preceding vehicle following control apparatus for placing serial to claim 1 or claim 2,
The follow-up control means detects a brake operation amount equal to or less than a maximum brake operation amount in the range of the play area during the follow-up control, and then when the brake operation is finished, the inter-vehicle distance is within a predetermined setting range. The tracking control is resumed when at least one of the following tracking restart conditions is satisfied, in which the relative speed with the preceding vehicle is close to zero or the preceding vehicle is the same vehicle before and after the brake operation. A preceding vehicle follow-up control device.

In the preceding vehicle follow-up control device according to claim 3 ,
The follow-up control unit performs a constant-speed running control that makes the vehicle run at a constant speed with the vehicle speed at the end of the brake operation as a set vehicle speed when the following resumption condition is not satisfied. . In the preceding vehicle follow-up control device according to any one of claims 1 to 4,
A preceding vehicle follow-up control device comprising a notification means for notifying the driver of the end of follow-up control. In the preceding vehicle follow-up control device according to any one of claims 1 to 5,
The follow-up control means is large in a deceleration direction among a deceleration command value corresponding to a brake operation amount equal to or less than a maximum brake operation amount in the range of the play area and a deceleration command value for maintaining a predetermined target inter-vehicle distance. A preceding vehicle follow-up control device characterized in that the vehicle is decelerated based on one of the deceleration command values. A throttle actuator that adjusts the amount of intake air into the engine;
A brake device that applies a braking force to each wheel by increasing the wheel cylinder pressure of each wheel by the master cylinder pressure increased according to the brake operation amount of the driver;
A brake actuator capable of increasing or decreasing each wheel cylinder pressure of the brake device independently of the brake operation;
Inter-vehicle distance detection means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle;
Have
The distance between the host vehicle and the preceding vehicle is detected, and the throttle actuator and the brake actuator are driven to control the host vehicle so that the distance between the host vehicle and the preceding vehicle matches a predetermined target vehicle distance. controls the driving force, the preceding vehicle follow-up control method of the preceding vehicle following control apparatus for performing tracking control for said preceding vehicle,
The brake device has a brake pedal play area that is an area of a brake operation amount in which a master cylinder pressure does not rise with respect to a brake operation amount;
When a brake operation amount exceeding the maximum brake operation amount in the range of the play area is detected during the tracking control, the tracking control is terminated,
If the maximum amount of brake operation following brake operation amount in the range of the play area during the follow-up control is detected, the brake operation amount temporarily stop the deceleration generated in accordance with the target inter-vehicle distance is detected The brake actuator and the throttle actuator are driven so as to generate a deceleration equal to or less than the deceleration when the engine braking force is generated at this time , and at this time , the deceleration increases as the brake operation amount increases , driver when the brake operation start time on the vehicle is accelerating, to generate acceleration speed between the deceleration when the current acceleration of the maximum amount of brake operation in the range of the play area, the braking operation earlier but characterized that you resume the follow-up control of the vehicle-to-vehicle distance at the end of the braking operation as a new target inter-vehicle distance when you quit Car tracking control method.

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