JP2019026210A - Drive assistance apparatus for emergency - Google Patents

Abstract

To prevent a sudden approach by the following vehicle due to insufficient acceleration due to a situation in which acceleration is not uniformly limited below an ACC target vehicle speed even if a driver presses an accelerator pedal when control for following a preceding vehicle is resumed after cancellation of control for retreat for emergency.SOLUTION: In a control after cancellation of retreat, an ACC requirement throttle opening degree θacc and a driver requirement throttle opening degree θdr set by a driver acceleration operation are compared (S12). If θacc<θdr, the own vehicle speed V and an ACC target vehicle speed Vacc set to a limited speed are compared (S13). If V<Vacc, an accelerator override, in which priority is given to the driver accelerator operation, is performed (S15). Conversely, if V≥Vacc, accelerator override limiting control, in which the upper limit of the own vehicle speed V is limited to the ACC target vehicle speed Vacc, is performed (S16).SELECTED DRAWING: Figure 3

Description

  The present invention relates to an emergency driving support device that performs driving support after evacuation control is released.

  Conventionally, the preceding vehicle following control (Adaptive Cruise Control, hereinafter referred to as “ACC control”) is combined with Lane Keep Assist control and Lane Departure Prevention (LDP) control. When the preceding vehicle is recognized in front of the vehicle, it is possible to automatically follow the preceding vehicle without departing from the lane, and when the preceding vehicle is not recognized, the set vehicle speed is set as the target vehicle speed. Is possible.

  At that time, even if the driver's level of consciousness declines, such as when the driver feels sleepy and sleeps intermittently, causing troubles in driving, driving will continue unless the driver operates the steering wheel or brakes. Will be.

  Therefore, when the driver's consciousness level during driving is constantly monitored and a decrease in consciousness is detected, or when an emergency stop switch provided in advance in the vehicle is turned on, a notification to that effect is given to the preceding and subsequent vehicles. Various techniques have been proposed for preventing accidents such as rear-end collisions.

  For example, in Patent Document 1 (Japanese Patent Laid-Open No. 2017-19411), when an emergency stop switch is turned on during ACC travel, execution of ACC control is stopped, and the vehicle is decelerated while continuing lane keeping control. And after that, when the accelerator operation is not performed for a predetermined time, it is determined that the operation is difficult to continue, and a technique for executing automatic stop control (hazard lamp blinking, notification by voice, brake operation, etc.) is disclosed. .

  This document also discloses a technique for canceling the automatic stop control when detecting an accelerator override in which the driver performs an accelerator operation during the automatic stop control.

JP 2017-19411 A

  However, in the technique disclosed in the above-described document, when the driver's accelerator override is detected, the automatic stop control is canceled, and thus the ACC control is automatically returned. However, for example, when the driver's consciousness is restored during stop control and the ACC control is automatically returned by accelerator override, if the accelerator pedal is depressed, normal accelerator override occurs, and the acceleration corresponding to the accelerator operation This has the disadvantage of increasing the speed.

  To cope with this, it is possible to suppress the speed increase that uniformly limits the acceleration due to the accelerator override when the automatic stop control is canceled and the ACC control is automatically returned, but it is necessary to keep the distance from the following vehicle. There is a disadvantage of being approached above.

  In the present invention, in view of the above circumstances, in the control after the evacuation control is canceled, even if the driver depresses the accelerator pedal and the accelerator override is performed, the acceleration is not uniformly limited, and there is a following vehicle. An object of the present invention is to provide an emergency driving support device that can prevent a sudden approach with the following vehicle and obtain high safety.

  The present invention relates to a driver state detection unit that detects a driver's consciousness level, and when it is determined that the driver's consciousness level is lowered based on the consciousness level detected by the driver state detection unit. A retraction control unit configured to perform retraction control of the vehicle; and a retraction release operation detection unit configured to detect a retreat release operation by the driver's operation. The retraction control unit is configured to release the retreat of the driver by the retreat release operation detection unit. In an emergency driving support apparatus further comprising a post-retraction control unit that executes control after retraction cancellation when an operation is detected, the post-retraction release control unit uses the speed limit acquired by the speed limit acquisition unit as a constant speed target vehicle speed. A constant speed target vehicle speed setting means set as a vehicle speed comparison means for comparing the vehicle speed of the host vehicle detected by the vehicle speed detection means with the constant speed target vehicle speed set by the constant speed target vehicle speed setting means. And when the vehicle speed comparison means determines that the vehicle speed of the host vehicle is lower than the constant speed target vehicle speed, a power output setting means for setting a power output corresponding to the accelerator operation of the driver, and the vehicle speed If the comparison means determines that the vehicle speed of the host vehicle exceeds the constant target speed, at least one of power output limiting means for setting a power output that limits the vehicle speed of the host vehicle to the constant target speed With.

  According to the present invention, in the control after retreat release, the control means after retreat release sets the power output corresponding to the driver's accelerator operation when the vehicle speed is lower than the constant target vehicle speed, and the vehicle speed. If the vehicle exceeds the speed limit, it has at least one of the modes to set the power output to limit the host vehicle speed to the constant target vehicle speed. Even in this case, the acceleration is not uniformly limited within the constant target speed, and when there is a subsequent vehicle, it is possible to prevent a sudden approach with the subsequent vehicle and to obtain high safety.

Overall configuration diagram of a vehicle driving support device Flowchart showing a control routine after retraction cancellation (part 1) Flowchart showing the control routine after retreat release (part 2) The control after retraction cancellation is shown, (a) is an explanatory diagram showing the setting of the inter-vehicle distance with the preceding vehicle, (b) is an explanatory diagram showing the accelerator override when the host vehicle speed is lower than the target vehicle speed, (c) Is an explanatory diagram showing the limitation of the accelerator override when the host vehicle speed exceeds the target vehicle speed

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The emergency driving support device 1 shown in FIG. 1 is mounted on the host vehicle M shown in FIG. The emergency driving support device 1 includes a retreat control unit 11, an ACC control unit (ACC_ECU) 21, an engine control unit (E / G_ECU) 31, a power steering control unit (PS_ECU) 32, and a brake control unit (BK_ECU) 33. I have. Each of the control units 11, 21, 31 to 33 is constituted by a well-known microcomputer having a CPU, a ROM, a RAM, etc., and the ROM performs fixed data and an operation set for each system. A control program is stored. Furthermore, these control units 11, 21, 31 to 33 are connected to each other through two-way communication via an in-vehicle communication line 19 such as a CAN (Controller Area Network).

  The evacuation control unit 11 determines the driver's consciousness level, and when it detects a decrease in the consciousness level, the evacuation control unit 11 controls the evacuation of the host vehicle M and performs control after the evacuation is released when the driver's consciousness is restored. Details will be described later.

  On the input side of the ACC_ECU 21, parameters necessary for executing the ACC control, such as a front recognition sensor 22 as a front recognition means, an accelerator opening sensor 23, a vehicle speed sensor 24 as a vehicle speed detection means, a throttle opening sensor 25, and the like. Each sensor / switch to be acquired is connected. The front recognition sensor 22 is composed of a stereo camera or a combination of a monocular camera and a radar sensor. When the front recognition sensor 22 recognizes the traveling environment ahead of the host vehicle M and recognizes the nearest preceding vehicle, the front recognition sensor 22 It detects the distance between cars and the difference in vehicle speed.

  The accelerator opening sensor 23 detects the accelerator opening, which is the amount of depression of the driver's accelerator pedal. The vehicle speed sensor 24 detects the vehicle speed of the host vehicle M (own vehicle speed). Further, the throttle opening sensor 25 detects the opening of an electronically controlled throttle (ETC) valve provided in the intake system of the engine that is a drive source.

  When the ACC_ECU 21 detects the nearest preceding vehicle by the front recognition sensor 22, the target for causing the host vehicle M to follow the preceding vehicle while maintaining a certain inter-vehicle distance based on the relative vehicle speed with respect to the preceding vehicle and the inter-vehicle distance. The vehicle speed and the target inter-vehicle distance are obtained, and a throttle opening signal is transmitted to the E / G_ECU 31 so that the current host vehicle speed and the inter-vehicle distance converge to the target vehicle speed and the target inter-vehicle distance. At that time, if it is predicted that the inter-vehicle distance from the preceding vehicle will be significantly closer than the target inter-vehicle distance with only the engine brake, a brake control signal is transmitted to the BK_ECU 33. Further, when a preceding vehicle is not detected within a predetermined distance range in front of the host vehicle M, the host vehicle M is driven at a constant speed at the vehicle speed (set vehicle speed) set by the driver.

  At that time, the ACC_ECU 21 recognizes the left and right lane markings that divide the lane in which the host vehicle M is traveling by the front recognition sensor 22, sets a target traveling path at the center of the left and right lane markings, and the host vehicle M A steering control signal is transmitted to the PS_ECU 32 so as to travel along the target traveling path (lane keeping control). Further, when the error (yaw angle) between the target traveling path and the actual traveling path (vehicle traveling path) is large and is predicted to deviate from one of the left and right lane markings, the yaw angle is corrected with respect to the PS_ECU 32. Then, a steering control signal for returning the own vehicle traveling path to the target traveling path is transmitted (lane departure prevention control).

  The E / G_ECU 31 controls the valve opening of the ETC valve, controls the engine output based on the ETC valve opening, and generates the engine brake by fully closing the ETC valve during traveling. The PS_ECU 32 controls the steering angle by driving an electric power steering (EPS) motor. The BK_ECU 33 adjusts the brake fluid pressure supplied to the brake wheel cylinders provided on each wheel of the host vehicle M. The brake fluid pressure adjusted by the drive signal from the BK_ECU 33 is adjusted to each brake. When supplied to the wheel cylinder, a braking force is generated on each wheel and the vehicle is forcibly decelerated.

  Further, a driver state detection sensor 16 as a driver state detection means and a release switch 17 are connected to the input side of the retreat control unit 11, and an alarm display unit 18 is connected to the output side. Further, the evacuation control unit 11 functions as an emergency evacuation control and a control after evacuation cancellation, as a consciousness level determination unit 12, an evacuation control unit 13 as an evacuation control unit, an alarm driving unit 14, and an evacuation release operation detection unit. The evacuation cancellation determination unit 15 is provided.

  The consciousness level determination unit 12 constantly monitors the driver's consciousness level detected by the driver state detection sensor 16, and when detecting a decrease in the consciousness level, sends an emergency evacuation signal to the evacuation control unit 13 and the alarm driving unit 14. Send.

  The driver state detection sensor 16 includes, for example, a monitoring camera that images a driver's facial expression (eyeball movement, eyelid movement, etc.), a biosensor that detects a driver's pulse, blood pressure, and the like, and a gripping force of a steering wheel (handle). It is a pressure sensor to detect. The consciousness level determination unit 12 examines the driver's consciousness level by combining one or more of the above-described sensors, and when detecting unusual behavior due to strong sleepiness, intermittent doze, loss of consciousness, etc. Judged as a decrease in consciousness level Note that since this consciousness level determination process is well known, a description thereof is omitted here.

  When the evacuation control unit 13 receives an emergency evacuation signal from the consciousness level determination unit 12, the evacuation control unit 13 transmits an ACC stop signal to the ACC_ECU 21, interrupts the ACC control, and executes the emergency evacuation control. In this emergency evacuation control, for example, based on the map information of the car navigation device, a place that can be safely evacuated in the direction of the own vehicle traveling path is searched, the place is set as a target point, and a target traveling path to the target point is set. To do. And a control signal is transmitted to each ECU31-33 in order to guide the own vehicle in the state decelerated to predetermined along the said target advancing path.

  Further, when the release control unit 13 receives a release signal from the save release determination unit 15 to be described later, the save control unit 13 executes control after the release release. Therefore, the evacuation control unit 13 also has a function as a control unit after the evacuation cancellation according to the present invention. This post-retraction release control will be described in detail later.

  When receiving the emergency evacuation signal from the consciousness level determining unit, the alarm driving unit 14 displays an alarm on the alarm display unit 18. This alarm display unit 18 is an internal speaker, an external speaker, a brake lamp, a hazard lamp, etc., and notifies the driver of a decrease in the level of consciousness, and also notifies the driver of the state of the driver to the preceding vehicle and the following vehicle. Or by flashing each lamp.

  Moreover, the alarm drive part 14 stops the alarm display by the alarm display part 18, when the cancellation signal from the evacuation cancellation | release determination part 15 mentioned later is received.

  The release switch 17 is used to release the emergency evacuation control by turning on when the driver's consciousness is restored. In the present embodiment, a momentary switch is employed, and when the driver's consciousness is restored, the ON signal is transmitted only for the time during which the driver himself or the passenger on the passenger seat is operating.

  This ON signal is received by the evacuation release determination unit 15. The evacuation release determination unit 15 receives an ON signal from the release switch 17 and detects whether or not the driver has performed an evacuation release operation. The ON signal is continued for a predetermined time (about 0.5 to 1 [sec]). If it is determined that the operation is a retreat release operation, a release signal is transmitted to the retreat control unit 13 and the alarm drive unit 14.

  Next, the post-retraction release control executed by the above-described retraction control unit 13 will be described in detail according to the post-retraction release control routine shown in FIGS. This post-evacuation release control routine is started when the evacuation release signal is received from the evacuation release determination unit 15 during emergency evacuation control.

  In this routine, first, in step S1, the host vehicle speed V detected by the vehicle speed sensor 24 is read, and in step S2, it is checked whether or not the vehicle is in a stopped state with V = 0. If it is determined that the running state is V> 0, the process proceeds to step S3. If it is determined that the vehicle is stopped when V = 0, the process jumps to step S4.

  When the process proceeds to step S3, the elapsed time or the travel distance after the emergency evacuation control is started is checked, and when it is determined that the time for judging that the consciousness has fully recovered has passed or the distance has been traveled, the process proceeds to step S4. Branch. If the time for judging sufficient recovery of consciousness has not elapsed or the vehicle has not traveled the distance, the process proceeds to step S5.

  When the process proceeds from step S2 or step S3 to step S4, the control after the cancellation is terminated, and the routine is terminated. When the control is terminated after the evacuation is released, the ACC control is released. Therefore, the driver can restart the ACC control by turning on an ACC switch (not shown) again.

  On the other hand, if it progresses to step S5, the speed limit of the road currently drive | working will be read. This speed limit is read from a speed limit sign standing on the road shoulder acquired by a stereo camera or a monocular camera provided in the front recognition sensor 22. Or, if a car navigation device is installed, it is acquired from the map information. Or you may make it acquire from Vix [VICS (trademark): Vehicle Information and Communication System] information. Therefore, these correspond to the speed limit acquisition means of the present invention.

  Thereafter, when the process proceeds to step S6, the ACC target vehicle speed Vacc is set at the limit speed (Vacc ← limit speed), and the process proceeds to step S7. Therefore, in the present embodiment, this speed limit is the set vehicle speed (constant target vehicle speed) during constant speed travel. The processing in steps S5 and S6 corresponds to the constant speed target vehicle speed setting means of the present invention.

  In step S7, the currently set ACC target inter-vehicle distance is read. This target inter-vehicle distance is set according to the preference of the inter-vehicle distance when the driver follows the preceding vehicle. For example, the target inter-vehicle distance is set stepwise as “long”, “medium”, “short”, or the longest Some can be set continuously from the shortest to the shortest.

  Then, in step S8, it is checked whether or not the target inter-vehicle distance is set to the longest. If it is set to the longest, the process jumps to step S10. If it is not set to the longest, the process proceeds to step S9, the ACC target inter-vehicle distance is set to the longest, and the process proceeds to step S10. As a result, as shown in FIG. 4A, even if the ACC target inter-vehicle distance of the host vehicle M is set to “short” or {medium} as shown by the alternate long and short dash line, it is uniformly the longest. By setting to, a safe inter-vehicle distance from the preceding vehicle is ensured. The ACC target inter-vehicle distance is a variable value that varies depending on the vehicle speed. The processing in step S9 corresponds to the inter-vehicle distance setting means of the present invention.

  Thereafter, when the process proceeds to step S10, the ACC required throttle opening degree θacc is read. The ACC required throttle opening degree θacc is calculated by the ACC_ECU 21. When the preceding vehicle is recognized, the ACC_ECU 21 obtains the target vehicle speed for setting the relative vehicle speed between the preceding vehicle and the host vehicle M to 0, and sets the ACC required throttle opening θacc for converging the host vehicle speed V to the target vehicle speed. Set. When the preceding vehicle is not recognized, the ACC required throttle opening degree θacc for converging the own vehicle speed V to the ACC target vehicle speed Vacc is set. And the said ACC request | requirement throttle opening (theta) acc is transmitted to E / G_ECU31, and the opening degree of an ETC valve is controlled. Here, the ETC valve sets the power output of the engine, and the ACC required throttle opening θacc becomes the required power output. Therefore, the processing in step S10 corresponds to the required power output setting means of the present invention.

  Next, in step S11, the driver request throttle opening degree θdr is read. The driver-requested throttle opening θdr is calculated by the ACC_ECU 21. The ACC_ECU 21 detects the accelerator opening, which is the depression amount of the driver's accelerator pedal, by the accelerator opening sensor 23, and calculates the driver requested throttle opening θdr, which is the opening of the ETC valve corresponding to the accelerator opening. As described above, since the ETC valve sets the power output of the engine, the driver required throttle opening θdr is the driver's required power output. Therefore, the processing in step S11 corresponds to the driver required power output setting means of the present invention.

  In step S12, the ACC required throttle opening degree θacc and the driver required throttle opening degree θdr are compared. Note that the processing in this step corresponds to the required power comparison means of the present invention.

  If θacc ≧ θdr, that is, the driver determines that the accelerator pedal is released or is depressed, the process branches to step S13. If θacc <θdr, it is determined that the driver is accelerating and the process proceeds to step S14. In step S13, the ACC control giving priority to the ACC required throttle opening degree θacc is continued, and contact with the following vehicle due to inadvertent deceleration is avoided.

  On the other hand, if it progresses to step S14, the own vehicle speed V and the ACC target vehicle speed Vacc will be compared. If V <Vacc, the process proceeds to step S15. If V ≧ Vacc, the process branches to step S16. Note that the processing in step S14 corresponds to the vehicle speed comparison means of the present invention.

  In step S15, the accelerator override control that gives priority to the driver's accelerator operation, that is, the valve opening (throttle opening) of the ETC valve detected by the throttle opening sensor 25 converges to the driver throttle opening θdr. Then, feedback control is performed and the routine is exited. As a result, when the host vehicle speed V is equal to or lower than the ACC target vehicle speed Vacc, the engine output, which is the power output, is accelerated and accelerated at the driver throttle opening θdr according to the amount of depression of the driver's accelerator pedal. Since it is an override, the acceleration is not limited uniformly, and as shown in FIG. 4B, contact with the following vehicle due to insufficient acceleration can be effectively avoided. The process in step S15 corresponds to the power output setting means of the present invention.

  On the other hand, when branching to step S16, the upper limit of the host vehicle speed V is limited to the ACC target vehicle speed Vacc in order to prevent contact with the preceding vehicle, acceleration is suppressed, and the host vehicle speed V is gradually decelerated to the ACC target vehicle speed Vacc. Execute accelerator override limit control and exit the routine. It is conceivable that the driver depresses the accelerator pedal inadvertently with the consciousness lowered, and the vehicle speed V exceeds the ACC target vehicle speed Vacc.

  Even in such a case, since the upper limit of the host vehicle speed V is regulated by the ACC target vehicle speed Vacc, the host vehicle M does not approach the preceding vehicle as shown in FIG. Can be prevented in advance. Note that the processing in step S16 corresponds to the power output limiting means of the present invention.

  As described above, according to the present embodiment, the driver's consciousness is recovered during the emergency evacuation control, and the release switch 17 is turned on for a predetermined time, so that the control after the evacuation release is executed. Therefore, the safe inter-vehicle distance from the preceding vehicle can be ensured.

  Further, even when the driver required throttle opening degree θdr exceeds the ACC required throttle opening degree θacc, when the host vehicle speed V is less than the ACC target vehicle speed Vacc, the accelerator operation of the driver is performed by the accelerator override control. Since priority is given, the acceleration is not limited uniformly, and contact due to a sudden approach with the following vehicle due to insufficient acceleration can be effectively prevented. On the other hand, when the host vehicle speed V is equal to or higher than the ACC target vehicle speed Vacc, the accelerator override control is limited, and the host vehicle speed V is decelerated so that the host vehicle speed V gradually converges to the ACC target vehicle speed Vacc. Acceleration caused by the driver inadvertently depressing the accelerator pedal is suppressed, sudden approach to the preceding vehicle is prevented, and contact can be prevented. As a result, even when the post-retraction control is executed in a state where the driver's consciousness has not sufficiently recovered, it is possible to obtain high safety without suddenly approaching the preceding vehicle and the following vehicle. .

  The present invention is not limited to the above-described embodiment. For example, the drive source is not limited to the engine, and may be an electric motor or both the engine and the electric motor. In this case, the E / G_ECU 31 is It is replaced with an electric motor or a power control unit that controls both the engine and the electric motor.

  Further, the retraction release operation detection means is not limited to the release switch 17 and can detect, for example, the gripping force of the driver on the steering wheel exemplified by the driving state detection sensor 16 as long as it detects an operation due to the driver's intention recovery. It may be a pressure sensor.

1 ... Emergency driving support device,
11 ... Emergency evacuation control unit,
12 ... Consciousness level determination unit,
13 ... evacuation control unit,
14 ... alarm drive part,
15 ... evacuation cancellation determination unit,
16 ... Driver state detection sensor,
17 ... Release switch,
18 ... alarm display section,
19 ... In-car communication line,
21 ... ACC control unit,
22 ... Forward recognition sensor,
23 ... accelerator opening sensor,
24 ... Vehicle speed sensor,
25 ... Throttle opening sensor,
31 ... Engine control unit,
32 ... Power steering control unit,
33 ... Brake control unit,
M ... own vehicle,
V ... Vehicle speed,
Vacc ... ACC target vehicle speed,
θacc: ACC required throttle opening,
θdr: Driver required throttle opening

Claims (3)

A driver state detecting means for detecting a driver's consciousness level;
When it is determined that the driver's consciousness level is lowered based on the consciousness level detected by the driver state detecting unit, the evacuation control unit that controls the evacuation of the host vehicle;
Retreat release operation detecting means for detecting a retreat release operation by the driver's operation,
In the emergency driving support device further comprising a post-retraction control unit that executes control after retraction cancellation when the retraction cancellation operation detection unit detects a driver's retraction cancellation operation,
The control means after the evacuation release is
A constant speed target vehicle speed setting means for setting the speed limit acquired by the speed limit acquisition means as a constant speed target vehicle speed;
Vehicle speed comparison means for comparing the vehicle speed of the host vehicle detected by vehicle speed detection means with the constant speed target vehicle speed set by the constant speed target vehicle speed setting means;
When the vehicle speed comparing means determines that the vehicle speed of the host vehicle is lower than the constant speed target vehicle speed, a power output setting means for setting a power output corresponding to the accelerator operation of the driver, and the vehicle speed comparing means If it is determined that the vehicle speed of the host vehicle is higher than the constant speed target vehicle speed, at least one of power output limiting means for setting a power output that limits the vehicle speed of the host vehicle to the constant speed target vehicle speed; An emergency driving support device comprising: A front recognition means for recognizing a traveling environment ahead of the host vehicle;
When the preceding vehicle is recognized by the forward recognition means, the required power output is set based on the target vehicle speed at which the relative vehicle speed between the preceding vehicle and the host vehicle is 0, and when the preceding vehicle is not detected, the constant speed Requested power output setting means for setting the requested power output based on the constant speed target vehicle speed set by the target vehicle speed setting means;
Driver required power output setting means for setting a driver required power output corresponding to the driver's accelerator operation;
Request power comparison means for comparing the required power output set by the required power output setting means with the driver required power output set by the driver required power output setting means,
The vehicle speed comparing means compares the vehicle speed of the host vehicle with the target vehicle speed when the required power output is lower than the driver required power output by the required power comparing means. Item 1. The emergency driving support device according to Item 1. The control means after the evacuation release is
The emergency driving support device according to claim 2, further comprising an inter-vehicle distance setting means for setting a target inter-vehicle distance between the preceding vehicle and the host vehicle to a preset longest inter-vehicle distance.

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