JPH06270830A - Automatic braking device for vehicle - Google Patents

Abstract

PURPOSE:To ensure a good operation of an automatic braking mean while preventing a handle feeling from being deteriorated, or the like by accurately restraining steering wheel operation during operation of the automatic braking means. CONSTITUTION:A device which comprises a computing unit 32 computing the distance between a vehicle and an obstacle and a relative speed and a control unit 40 for operating an actuator 17 for automatic braking according to the operation results, is constituted such that a control signal is output by this unit 40 to a steering restraining pad 51 for controlling steering force according to signals from sensors 41-45 detecting the operation conditions of vehicle and the conditions of driver himself.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic braking system for a vehicle which automatically applies a braking force to wheels when an obstacle to the running of the vehicle is detected.

[0002]

2. Description of the Related Art Conventionally, as a means for improving the running safety of a vehicle, an automatic braking device has been proposed which automatically applies a braking force to wheels when an obstacle to the running of the vehicle is detected. There is.

As a part of that, for example, Japanese Patent Publication No. Sho 39-56.
In Japanese Patent Publication No. 68, the distance and relative speed between the vehicle and an obstacle in front of the vehicle are continuously detected optically or by using ultrasonic waves, and the distance and relative speed are detected from the detected distance and relative speed. It is disclosed that the possibility of contact between a vehicle and an obstacle is determined, and when it is determined that there is a possibility of contact, an actuator is activated to automatically brake each wheel. .

[0004]

By the way, according to the automatic braking device of this kind, since the control is performed so as to avoid contact with the obstacle without the driver's operation, the operation of the automatic braking device is performed. It is preferable that the driver does not operate inside, but rather, if the driver notices an obstacle and operates the steering wheel suddenly in order to avoid it, the control of the automatic braking device will be confused and rather the traveling state May become unstable.

Therefore, the present invention secures the original operation of the automatic braking device by suppressing the driver's operation of the steering wheel during the operation of the automatic braking device as described above, and particularly suppresses the operation of the steering wheel. In addition to the driving state of the vehicle, it is an object of the present invention to accurately handle the state of the driver.

[0006]

In order to solve the above problems, the present invention uses the following means.

First, the invention according to claim 1 of the present application (hereinafter,
The first invention) is an automatic braking of a vehicle having an obstacle detecting means for detecting an obstacle against the traveling of the own vehicle, and an automatic braking means for applying a braking force to the wheels when the obstacle is detected by the means. In the device, the steering force setting means for setting the steering force so that the steering wheel operation becomes heavy during the operation of the automatic braking means, and the steering force during operation of the automatic braking means set by the setting means Steering force correction means for making a correction based on a predetermined condition related to the state.

The invention according to claim 2 (hereinafter referred to as the second invention) is provided with steering speed detecting means for detecting the speed of the steering wheel operation, in addition to the structure of the first invention. When the detected steering speed is high, steering force correction means for correcting the steering force set by the steering force setting means during operation of the automatic braking means in a direction in which the steering wheel operation becomes heavy is provided.

The invention according to claim 3 (hereinafter referred to as the third invention) is also provided with a driving attitude detecting means for detecting the driving attitude of the driver, in addition to the configuration of the first invention, and the detecting means. Steering force correction means for correcting the steering force during operation of the automatic braking means set by the steering force setting means in a direction in which the steering wheel operation becomes heavy when the driving posture detected by .

Further, the invention according to claim 4 (hereinafter, referred to as the fourth
In addition to the configuration of the first invention, the invention includes a mental state detecting means for detecting the mental state of the driver, and when the mental state of the driver detected by the detecting means is not normal, the steering force is It is characterized in that steering force correction means for correcting the steering force set by the setting means during the operation of the automatic braking means in the direction in which the steering wheel operation becomes heavy is provided.

[0011]

According to the above construction, according to any of the first to fourth aspects of the invention, when the automatic braking means is operating by detecting an obstacle to the traveling of the vehicle, the steering force setting means operates the steering wheel. Since the steering force is set so that the vehicle becomes heavier, unnecessary steering wheel operation by the driver is suppressed, and the automatic braking means operates well.

Since the steering force in that case is corrected on the basis of a predetermined condition related to the driver's condition, the steering feel is prevented from being deteriorated by making the steering operation heavier than necessary. Therefore, unnecessary operation of the steering wheel that hinders good operation of the automatic braking means is effectively suppressed.

As a condition related to the state of the driver, since the speed of the steering wheel operation is detected in the second invention, the steering force is detected when a so-called panic steering wheel in which the steering wheel operation is rapidly performed is detected. By making it particularly heavy, it becomes possible to immediately prevent such an operation.

Further, according to the third aspect of the invention, since the sitting posture of the driver is detected, when the inappropriate sitting posture due to the abnormal behavior of the driver is detected, the steering force is increased to make the abnormal steering. It is possible to avoid operating the steering wheel.

Further, according to the fourth aspect of the present invention, since the driver's mental state is detected, the steering force is similarly increased when the unstable mental state is detected to prevent the unstable steering wheel operation. It becomes possible.

Therefore, in any of the second to fourth aspects of the invention, the abnormal or unnecessary steering wheel operation is suppressed depending on the driver's condition, and the required avoidance operation for the obstacle of the automatic braking device is further effective. Will be secured.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a hydraulic circuit of an automatic braking device according to the present embodiment. This hydraulic circuit responds to a stepping force via a master back 2 when a driver steps on a brake pedal 1. A master cylinder 3 for generating a braking pressure, an automatic braking valve unit 4 to which the braking pressure generated by the master cylinder 3 is supplied, and an ABS (anti-skid brake system) valve unit 5; Is supplied to the brake device 6 of each wheel via these valve units 4 and 5.

The automatic braking valve unit 4 has a shutter valve 11 that connects and disconnects the master cylinder 3 and the brake device 6 side, a pressure increasing valve 12, and a pressure reducing valve 13. Three valves 11,1
Both 2 and 13 are electromagnetic 2-port 2-position switching valves. Further, between the pressure increasing valve 12 and the master cylinder 3, an oil pump 14 driven by a motor 14a and an accumulator 15 that stores the pressure oil discharged from the pump 14 and maintains it at a constant pressure are provided. It is installed.

When the shutter valve 11 is in the open position, the braking pressure corresponding to the depression force of the brake pedal 1 generated by the master cylinder 3 is supplied to the brake device 6 of each wheel to control each wheel. Power is working.

When the shutter valve 11 is in the closed position, the pressure increasing valve 12 is in the open position and the pressure reducing valve 1 is in the open position.
By switching 3 to the closed position, respectively, the pressure oil from the accumulator 15 is supplied to the brake device 6 of each wheel to exert a braking force, and conversely, the pressure increasing valve 12 is set to the closed position and the pressure reducing valve 13 is set. By switching to the open position, the pressure oil is returned from the brake device 6 and the braking force is weakened.

As shown in FIG. 2, the shutter valve 11, the pressure increasing valve 12 and the pressure reducing valve 13 in the automatic braking valve unit 4 are switched via the actuator 17 by a control signal from the control box 16. It is like this.

On the other hand, the ABS valve unit 5 is
Each wheel has a 3-port 2-position switching valve 21 provided for each wheel, and the braking pressure supplied to each brake device 6 is controlled by the switching operation of the valve 21 during braking, so that each wheel is It is designed to be braked with an optimum braking force without causing a lock.

In addition to the switching valve 21, the ABS valve unit 5 includes an oil pump 22 and an accumulator 23 driven by a motor 22a.
24 and the like are provided.

The brake device 6 for each wheel is composed of a disk 25 that rotates integrally with the wheel, a caliper 26 that holds the disk 25 by receiving braking pressure from the master cylinder 3 side, and the like.

Next, the control system of the automatic braking device will be described with reference to FIG.

This system includes an ultrasonic radar unit 3
1 is provided. The radar unit 31 is attached to the front part of the vehicle body of the vehicle, transmits ultrasonic waves from the ultrasonic wave transmitting section to obstacles such as other vehicles in front of the own vehicle, and reflects by hitting the obstacles. The receiving unit is configured to receive the incoming reflected wave.

Then, the signal from the radar unit 31 is input to the arithmetic unit 32, and the arithmetic unit 32 detects the forward and backward movements of the vehicle based on the delay time (Doppler shift) from the transmission point of the radar reception wave. The distance to the obstacle and the relative speed are calculated.

Further, this system is provided with a pair of radar head units 33, 34 attached to both left and right sides of the front part of the vehicle body of the vehicle. These radar head units 33 and 34 are configured to emit pulsed laser light from an emission unit toward an obstacle in front of the vehicle and to receive reflected light reflected by the obstacle at the reception unit. I'm standing.

Then, these radar head units 3
The signals from the reference numerals 3, 34 are input to the arithmetic unit 32 via the signal processing unit 35, and the arithmetic unit 32
Then, the distance and the relative speed between the own vehicle and the front obstacle are calculated on the basis of the delay time from the transmission point of the laser reception light.

In this case, the calculation unit 32 gives priority to the calculation result of the distance and the relative speed by the system of the radar head units 33 and 34, and the ultrasonic radar unit 31.
The calculation results of the distance and the relative speed according to the system are used as an auxiliary.

Here, the above-mentioned both radar head units 3
The direction of transmission and reception of the pulsed laser light by the motors 3, 34 is the motor 3
6 can be changed in the horizontal direction, and the operation of the motor 36 is controlled by the arithmetic unit 32. Further, an angle sensor 37 for detecting the transmission / reception direction of the pulsed laser light by the motor 36 is provided, and the detection signal of the sensor 37 is used as the arithmetic unit 3.
The transmission / reception direction of the pulsed laser light is added to the calculation of the distance and the relative speed to the front obstacle by the system of the radar head units 33 and 34 in the calculation unit 32.

Further, this control system is provided with a control function of the braking force applied to each wheel and a control function of the steering force of the steering wheel in addition to the above-described function of calculating the distance and the relative speed with respect to the front obstacle. Has been.

That is, the control system is provided with a control unit 40, and the control unit 40 has a signal from a vehicle speed sensor 41 for detecting a vehicle speed, a signal from a steering angle sensor 42 for detecting a steering angle of a steering wheel, and a road surface. From a road surface μ sensor 43 for detecting the friction coefficient of the vehicle, a signal from a seating position sensor 44 provided in the driver's seat to detect the sitting state of the driver, and a signal provided from the steering wheel to detect the heart rate of the driver. A signal from the heart rate sensor 45 is input.

Then, the control unit 40 sets the braking force to be applied to each wheel based on the necessary one of these signals, the distance to the front obstacle calculated by the calculation unit 32, and the relative speed. Then, a control signal is output to the actuator 17 that operates the automatic braking valve unit 4 shown in FIG. 2 so that the braking force is obtained. Further, the steering force of the steering wheel is set during execution of the automatic braking control, and a control signal is output to the steering suppression pad 51 so that the steering force can be obtained.

Here, the steering restraint pad 51 is shown in FIG.
As shown in FIG. 5, the steering shaft 53 provided with a handle 52 is provided to suppress the rotation of the steering shaft 53.
By sandwiching the rotary disk 54 fixedly mounted on the both sides, resistance to the rotation of the shaft 53 is given. Then, the resistance is the control unit 4 of FIG.
The force required to steer the steering wheel 52 against this resistance by being controlled by the control signal from 0,
That is, the steering force is set.

Next, the calculation unit 32 calculates the distance and relative speed between the vehicle and the front obstacle, and based on the result, the control unit 40 applies the braking force to the brake device 6 of each wheel. The specific operation of the steering force control by the control unit 40 in the state where the automatic braking control by the above is performed will be described with reference to FIGS.

First, the control unit 40, in step S1 of the flow chart of FIG. 5, detects each of the sensors 41 to 41 shown in FIG.
Each signal indicating the vehicle speed, the steering angle of the steering wheel, the road friction coefficient, the sitting posture of the driver, and the heart rate is input from 45, and then, in step S2, it is determined whether or not the automatic braking control is started. When the automatic braking control is started, the basic steering force P0 is set in step S3.

The basic steering force P0 is set by reading a value corresponding to the vehicle speed at that time from a preset map as shown in FIG. In this case, in this map, the value of the basic steering force P0 is set to increase as the vehicle speed increases, which suppresses excessive steering wheel operation during high-speed traveling.

The control unit 40 then proceeds to step S
In S4 and S5, the first correction coefficient K1 and the second correction coefficient K2 are set.

These correction coefficients K1 and K2 are also set as maps as shown in FIGS. 7 and 8, of which the first correction coefficient K1 is set to a larger value as the steering angle is larger. The second correction coefficient K2 is set to a larger value as the road surface friction coefficient is smaller. In order to suppress excessive steering operation, it is desirable to increase the steering force as the steering angle increases.Also, even when the road surface friction coefficient is small, the steering force is suppressed to suppress excessive steering operation. This is because it is desirable to increase the size.

The control unit 40 then proceeds to step S
In step 6, the target steering force P is calculated by multiplying the basic steering force P0 set as described above by the first and second correction coefficients K1 and K2. In this case, as is apparent from the above description, the target steering force P has a larger value as the vehicle speed is higher, the steering angle is larger, and the road surface friction coefficient is smaller.

When the target steering force P is set in this way, the control unit 40 then performs control to correct the target steering force P in step S7 according to the driver's condition.

This control is performed according to the subroutine of FIG. 9. First, at step S11, the temporal change rate of the steering angle .theta. Of the steering wheel, which is indicated by the signal from the steering angle sensor 42, that is, the steering speed .DELTA..theta. Or not. Then, during the automatic braking control, when the steering wheel operation is performed at a speed equal to or higher than the predetermined value α, in other words, the driver notices an obstacle and a sudden steering wheel steering operation called a panic steering wheel is attempted to avoid the obstacle. If the user wants to perform the step S1, the control unit 40 proceeds from step S11 to step S1.
2 is executed, and the target steering force P set according to the flowchart of FIG. 5 is further increased by 1.5 times.
As a result, the panic handle as described above is immediately blocked, and the automatic braking control is favorably performed.

If the steering wheel is not operated, step S14 is executed after step S11 through step S13, and it is determined whether the seating posture of the driver is normal based on the signal from the seating position sensor 44. To determine. Then, even if the steering wheel operation as described above is not performed at present, it is possible to determine that the driver is mentally panicked if the sitting posture is not normal. Since there is a high possibility that such a sudden steering wheel operation is performed, the control unit 40 also increases the target steering force P by 1.5 times in step S12 in this case as well.

Further, even if the sitting posture is normal, even when the heart rate of the driver detected by the heart rate sensor 45 is abnormally high, it is considered that the driver is in a mental panic state. Therefore, steps S15 to S12 are executed to increase the target steering force P by 1.5 times.

Therefore, also in these cases, the abnormal steering operation is suppressed, and the automatic braking control is favorably performed.

On the other hand, the steering wheel is not operated ((Δ
θ = 0), and when the sitting posture and the heart rate of the driver are also normal, the control unit 40 executes step S16 and does not correct the target steering force P set according to the flowchart of FIG. Hold in value.

Further, when the steering wheel is operated at a speed smaller than the predetermined value α, the control unit 40
Executes steps S11, S13 to step S17 to reduce the target steering force P to 0.8 times. In other words, when a gentle steering wheel operation is performed, it can be determined that the driver's condition is stable and can handle the situation correctly. In this case, the steering force is reduced to ensure a good steering feel. To do.

Then, the control unit 40 sends a control signal to the steering suppression pad 51 shown in FIGS. 3 and 4 in step S8 of the flowchart of FIG. 5 so that the target steering force P corrected as described above is obtained. Output. As a result, the steering force required to operate the steering wheel is controlled to the target steering force P, and this steering force is set to a magnitude according to the traveling state and the driver's state. .

In the above embodiments, the steering restraining pad 51 that gives a resistance to the rotation of the steering shaft 53 is used as a means for controlling the steering force. However, in addition to this, control of the assisting force in the power steering system is used. It is also possible to control the steering force by, for example, variably controlling the gear ratio of the steering gear mechanism.

In the above embodiment, the heart rate is detected as the driver's mental state, but other than this, it is also possible to detect brain waves, blood pressure, etc., and the eyepoint sensor is used for drowsiness. It is also possible to detect the state and control the steering force.

[0053]

As described above, the automatic braking device according to the present invention is provided with the automatic braking means for automatically applying the braking force to the wheels when the obstacle against the running of the vehicle is detected. In a vehicle, a steering force setting means for setting a steering force so that a steering wheel operation becomes heavy during operation of the automatic braking means, and a steering force set by the setting means are set to a predetermined condition related to a driver's state. Since the steering force correcting means for correcting the steering force is provided, the steering force is controlled according to the driver's own state in addition to the driving state of the vehicle during the automatic braking control.

As a result, unnecessary steering wheel operation during the operation of the automatic braking means is suppressed, and the automatic braking control is favorably performed by the automatic braking means, and the steering force in that case is related to the state of the driver. Since it is corrected based on the specified conditions, unfavorable steering wheel operation due to, for example, panic steering wheel, sitting posture, or abnormality in mental state, etc., while avoiding deterioration of steering wheel feeling caused by making the steering wheel operation heavier than necessary. Is effectively suppressed, and the required operation of the automatic braking means is more effectively ensured.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of an automatic braking device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a hydraulic circuit in the automatic braking device.

FIG. 3 is a control system diagram of the same automatic braking device.

FIG. 4 is a schematic diagram of a steering mechanism including steering force control means.

FIG. 5 is a flowchart showing a specific operation of steering force control by the control unit.

FIG. 6 is a map of a basic steering force with respect to a vehicle speed used in the control.

FIG. 7 is a map of a first correction coefficient for a steering angle used in the control.

FIG. 8 is a map of a second correction coefficient for a road surface friction coefficient used in the control.

9 is a flowchart showing a subroutine of steering force correction control in the flowchart of FIG.

[Explanation of symbols]

4, 17 Automatic braking means (valve unit, actuator) 31, 33, 34 Obstacle detecting means (radar unit) 40 Steering force setting means, steering force correcting means (control unit) 42 Steering speed detecting means (steering angle sensor) 44 Driving posture detecting means (seating position sensor) 45 Mental state detecting means (heart rate sensor)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location B62D 113: 00 137: 00 (72) Inventor Hiroe Ie 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture No. Mazda Co., Ltd.

Claims (4)

[Claims] 1. An automatic braking device for a vehicle, comprising: obstacle detecting means for detecting an obstacle with respect to traveling of the vehicle; and automatic braking means for applying a braking force to wheels when an obstacle is detected by the means. Therefore, during the operation of the automatic braking means, the steering force setting means for setting the steering force so that the steering wheel operation becomes heavy, and the steering force during the operation of the automatic braking means set by the setting means An automatic braking device for a vehicle, comprising: a steering force correction unit that corrects based on a predetermined condition related to a state. 2. An automatic braking device for a vehicle, comprising: an obstacle detecting means for detecting an obstacle with respect to the traveling of the own vehicle; and an automatic braking means for applying a braking force to the wheels when the obstacle is detected by the means. Therefore, during the operation of the automatic braking means, the steering force setting means for setting the steering force so that the steering wheel operation becomes heavy, the steering speed detection means for detecting the speed of the steering wheel operation, and the detection means When the steering speed is fast, a vehicle steering system is provided with steering force correction means for correcting the steering force set by the setting means during operation of the automatic braking means in a direction in which the steering wheel operation becomes heavy. Braking device. 3. An automatic braking device for a vehicle, comprising: obstacle detecting means for detecting an obstacle with respect to the traveling of the own vehicle; and automatic braking means for applying a braking force to the wheels when the obstacle is detected by the means. Therefore, during the operation of the automatic braking means, a steering force setting means for setting the steering force so that the steering wheel operation becomes heavy, a driving posture detecting means for detecting the driving posture of the driver, and the detecting means for detecting the driving posture. And a steering force correction means for correcting the steering force during operation of the automatic braking means set by the setting means in a direction in which the steering wheel operation becomes heavy when the driving posture is not normal. Automatic braking system. 4. An automatic braking device for a vehicle, comprising: an obstacle detecting means for detecting an obstacle with respect to the traveling of the own vehicle; and an automatic braking means for applying a braking force to the wheels when the obstacle is detected by the means. Then, during the operation of the automatic braking means, the steering force setting means for setting the steering force so that the steering wheel operation becomes heavy, the mental state detecting means for detecting the mental state of the driver, and the detecting means for detecting the mental state. When the driver's mental state is not normal, there is provided steering force correcting means for correcting the steering force set by the setting means during the operation of the automatic braking means in a direction in which the steering wheel operation becomes heavy. Automatic braking system for vehicles.