JP4013051B2 - Driving assistance device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving support device installed in a vehicle in order to improve vehicle safety and reduce fatigue, and more particularly, to a driving support device that prevents excessive dependence of a driver.
[0002]
[Related background]
As a driving support device, a driving control device that automatically generates braking force according to the vehicle interval from the preceding vehicle or increases or decreases the engine output to maintain the set vehicle interval, or the vehicle may deviate from the driving lane. In some cases, automatic steering devices are known that automatically steer in the return direction to prevent lane departure (see, for example, Japanese Patent Application Laid-Open Nos. 11-242800 and 10-1000091).
[0003]
[Problems to be solved by the invention]
In recent years, the driving support device has been enhanced in its support capability, but the drive support device has not been able to perform fully automatic driving in all vehicle driving environments, and its support capability is naturally constant. There are limits. Therefore, even if the brake pedal and the steering wheel (steering wheel) are automatically operated by the driving support device, the driver himself / herself should perform the driving operation under a situation where automatic driving is difficult.
[0004]
Nevertheless, depending on the driver, it is considered that the driver may be overly dependent on the device beyond the support capability of the driving support device, and in this case, the vehicle may not be properly driven.
Then, an object of this invention is to provide the driving assistance device which the driver did not depend excessively.
[0005]
[Means for Solving the Problems]
The driving support device according to claim 1 includes a dependency degree determined by the dependency degree determining unit based on a driving operation of the driver or a plurality of times of driving of the vehicle operating unit by the actuator based on a rate at which the operating unit is driven by the actuator. Depending on the vehicle running state detected by the detection means, the operation start timing and the operation force of the operation part by the actuator are set by the setting means, and the actuator is operated so that the operation part operates with the set operation force from the operation start time. Drive control is performed by an actuator control means.
[0006]
According to the first aspect of the present invention, when a driving operation is performed by the driver when it is necessary to change the vehicle traveling state, the operating unit is activated according to the driving operation, and the vehicle traveling state changes. When sufficient driving operation is not performed by the preset operation start timing, the actuator is driven and controlled by the actuator control means, and the operating unit is operated with the preset operating force, and the vehicle running state To change. In the present invention, in order to prevent the driver from excessively depending on the driving support device, the dependence of the driver on the driving support device is determined based on the drive ratio of the actuator in the driving of the operation unit multiple times, and this dependency is determined. Depending on the degree, the operation start timing and the operation force of the operation unit by the actuator are set in the next and subsequent times. For example, if the dependence is large, the operation start timing is delayed and the actuation force is increased, while if the dependence is small, the actuation start timing is advanced and the actuation force is reduced.
[0007]
Therefore, if the dependence on the driving support device in driving the operating unit up to this time is large, the operation start timing of the operating unit by the actuator is delayed when the operating unit is driven from the next time, so it is necessary to change the vehicle traveling state. When this occurs, there is a high probability that the driver will perform a driving operation without waiting for the actuator to start operating the operating unit. In addition, if the operation is not performed before the operation start time even though the operation start time is delayed, the operation start time is changed so that the operation start time is further delayed. The suspicion that a driving operation is performed during driving is further enhanced, thereby preventing excessive dependence. In addition, when the operation start time is set to a later time, the operation force is set to a larger value, while when the operation start time is set to an earlier time, the operation force is set to a smaller value, so that the operation start time is set. Regardless of whether the operation is late or early, the operation completion timing of the operation unit becomes constant, and driving support by the driving support device is appropriately performed.
[0008]
Preferably, the dependency degree determining means determines whether the driving is based on the driving operation or the actuator operation every time the operating unit is driven. More preferably, the dependency degree determining means determines that the operating portion is driven by the driving operation and the operation of the actuator that has started earlier. According to such a preferred aspect, the degree of dependence of the driver on the driving support device can be determined simply and reliably.
[0009]
The invention according to claim 2 is characterized in that the actuator comprises a brake actuator that drives the brake system. For example, the setting means sets a deceleration start timing and a target deceleration of the brake system by the brake actuator, and controls the actuator. The means drives and controls the brake actuator so that the braking system generates a braking force for decelerating the vehicle at the target deceleration from the deceleration start timing.
[0010]
According to the second aspect of the present invention, the driving support device includes the brake actuator that can operate the brake system independently of the braking operation by the driver, and can avoid collision with, for example, a preceding vehicle or an obstacle. This automatic brake device sets the operation start time (deceleration start time) and operation force (braking force) of the brake system by the brake actuator according to the driver's dependence on the automatic brake device. Thus, excessive dependence on the automatic brake device is surely prevented.
[0011]
The invention according to claim 3 is characterized in that the actuator comprises a steering actuator for driving the steering system, for example, the setting means sets the steering start timing and the target steering angle of the steering system by the steering actuator, and controls the actuator. The means drives and controls the steering actuator so that a steering force for steering to the target steering angle is generated in the steering system after the steering start timing.
[0012]
According to a third aspect of the present invention, the driving assistance device includes a steering actuator that can operate the steering system separately from the steering operation by the driver, and can prevent, for example, deviation from the traveling lane. This automatic steering device is configured to automatically steer by setting the operation start timing (steering start timing) and the operating force (steering force) of the steering system by the steering actuator according to the degree of dependence on the driver's automatic steering device. Prevent excessive reliance on equipment.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a driving support apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
The driving assistance device of the present embodiment is configured as an automatic brake device that automatically generates a braking force and maintains a safe distance when there is a possibility that the distance to the preceding vehicle or an obstacle may be less than the safe distance.
[0014]
As shown in FIG. 1, a radio wave radar 2 that scans a millimeter wave in a beam shape toward the front of the vehicle and receives a millimeter wave reflected by a preceding vehicle or an obstacle is mounted on the front portion of the vehicle 1. A CCD camera 4 for detecting obstacles on the road, lanes (white lines) and the like is mounted on the ceiling in the passenger compartment. The engine 6 is provided with a throttle actuator 12 that opens and closes the throttle valve 8 in accordance with the driver's accelerator operation. The front wheels 20 and the rear wheels 22 are provided with service brakes 24 such as disc brakes. And the wheel speed sensor 32 for detecting the wheel speed Vs of each wheel is installed in each of the left and right rear wheels 22 which are driven wheels.
[0015]
Each service brake 24 is connected to a brake pedal 28 via a master cylinder 26 having a negative pressure booster, and hydraulic pressure generated in the master cylinder 26 in response to a brake pedal operation by the driver is supplied to each service brake 24. Sometimes, braking force is applied to the wheels 20 and 22. A brake switch 29 (FIG. 2) that is turned on when the brake pedal is operated is provided in the vicinity of the brake pedal 28. Further, the master cylinder 26 is provided with a brake actuator 30 that generates hydraulic pressure in the master cylinder 26 regardless of the driver's brake pedal operation. An operation switch 38 is provided near the steering 34 for the driver to instruct the automatic brake device to execute automatic brake control.
[0016]
An ECU (electronic control unit) 50 installed in the passenger compartment includes an input / output device (not shown), a storage device, a central processing unit, a timer counter, and the like, and performs engine control and automatic brake control. As shown in FIGS. 1 and 2, various sensors such as a radio wave radar 2, a CCD camera 4, a brake switch 29, a wheel speed sensor 32, and an operation switch 38 are connected to the input side of the ECU 50, and to the output side of the ECU 50. The throttle actuator 12, the brake actuator 30, and the display device 40 are connected.
[0017]
As shown in FIG. 2, the ECU 50 includes a distance calculation unit 51 in connection with the automatic brake control. The distance calculation unit 51 is connected to the radio wave radar 2, the CCD camera 4, the wheel speed sensor 32, and the operation switch 38, calculates the vehicle speed Va of the own vehicle based on the vehicle speed information Vs from the wheel speed sensor 32, and the radio wave radar The distance L between the preceding vehicle and the obstacle and the own vehicle is calculated based on the distance information Lr from 2, and the preceding vehicle, the obstacle and the own vehicle are calculated from the previously calculated distance L and the currently calculated distance L. The relative speed ΔV is calculated.
[0018]
The setting unit 52 stores a map (not shown) showing the relationship among the distance L, the vehicle speed Va, and the basic target deceleration (required deceleration) αta. The setting unit 52 refers to this map and stores the distance L and A basic target deceleration rate αta (not shown) corresponding to the vehicle speed Va is obtained, and then a basic deceleration start timing Tsa (not shown) is obtained based on the required deceleration time obtained from the basic target deceleration rate αta and the relative speed ΔV. It is like that.
[0019]
The automatic brake device of the present embodiment sets the deceleration start timing and the target deceleration according to the driver's dependence on the device. For this reason, in the setting unit 52, the driver will be described later. The target deceleration rate αt and the deceleration start timing Ts are obtained by adding the correction amounts Δαt and ΔTs determined according to the degree of dependence on the automatic brake device to the basic target deceleration rate αta and the basic deceleration start timing Tsa, respectively.
[0020]
When the deceleration start timing Ts arrives, the vehicle speed control unit 53 as the actuator control means controls the vehicle speed Va so that the actual acceleration (differential value of the vehicle speed Va) α of the own vehicle becomes the target deceleration rate αt. To ensure that the actual distance L does not fall below the safe distance.
In the automatic brake device having the above configuration, when the operation switch 38 is turned on, the distance calculation unit 51 calculates the average value of the wheel speed information Vs of the pair of wheel speed sensors 32 as the vehicle speed Va of the vehicle 1. When the preceding vehicle or obstacle is recognized from the detection information from the radio wave radar 2 or the CCD camera 4, the actual distance L and the relative speed ΔV between the own vehicle and the preceding vehicle or obstacle are detected from the distance information Lr of the radar 2. Is done. The setting unit 52 calculates the basic target deceleration rate αta and the basic deceleration start timing Tsa based on the detection information L, Va, ΔV, and further adds the first and second correction amounts Δαt, ΔTs to the calculated values αta, Tsa. Are respectively added to calculate the target deceleration rate αt and the deceleration start timing Ts.
[0021]
When the deceleration start timing Ts arrives, under the control of the vehicle speed control unit 53, the throttle actuator 12 is driven so that the throttle valve 8 is closed, the engine output is reduced, and the actual acceleration α of the vehicle 1 is reduced by the target. The brake actuator 30 is driven so as to reach the speed αt, the braking force is applied to the wheels 20 and 22 by the service brake 24, and the vehicle 1 decelerates.
[0022]
Further, the ECU 50 includes a display driving unit 54 connected to the distance calculation unit 51 and the setting unit 52, and the driving unit 54 causes the display device 40 to display the presence of a preceding vehicle and an obstacle and the time to start deceleration. . The display device 40 is installed as an information providing device on an instrument panel or the like of the vehicle 1.
As described above, the automatic brake device of the present embodiment basically has a conventionally known automatic brake function, but is characterized by preventing the driver from excessively depending on the automatic brake function. Specifically, the target deceleration and the deceleration start timing are variably set according to the dependence.
[0023]
For this reason, the ECU 50 includes a dependency degree determination unit 55 that determines the degree of dependency of the driver on the automatic brake device. The determination unit 55 is connected to the brake switch 29 and the vehicle speed control unit 53, for example, and constantly monitors the on / off state of the brake switch 29 (hereinafter referred to as the output of the brake switch 29) and the output of the vehicle speed control unit 53. ing. The determination unit 55 detects whether the output of the brake switch 29 or the output of the vehicle speed control unit 53 is generated first in relation to each braking operation of the service brake 24 (steps S1 and S2 in FIG. 3), and the vehicle speed control is performed. When the output of the unit 53 is generated first, the dependence number Nd is incremented by “1”, and when the brake switch 29 is turned off and the output of the vehicle speed control unit 53 disappears, that is, the braking operation of the brake 24 is finished. When this is done, the number of times of braking Nb is incremented by "1" (steps S3, S4 and S5).
[0024]
When the number of times of braking Nb reaches a predetermined number of times N (for example, an appropriate number of times from 10 to 100) (step S6), the dependence determination unit 55 outputs the output of the vehicle speed control unit 53 in the braking operation of the predetermined number of times N. The number of occurrences (dependence number) Nd generated before the output of the brake switch 29 is confirmed, and the dependence ratio Dr (%) is calculated by multiplying the value obtained by dividing the dependence number Nd by the predetermined number N by 100. In addition, the dependence degree D corresponding to the dependence ratio Dr is obtained from the map illustrated in FIG.
[0025]
Here, the predetermined dependency ratio Dra is a determination reference value for determining the degree of dependency, and is set to an appropriate value (for example, 30%) in advance according to the support capability of the automatic brake device. If the dependency ratio Dr calculated as described above exceeds the predetermined dependency ratio Dra, it indicates that the dependency is large, and if it is below the value Dr, it indicates that the dependency is small.
[0026]
In the setting unit 52, the first correction coefficient K1 for the target deceleration and the second correction coefficient K2 for the deceleration start timing corresponding to the dependency D are obtained from the map illustrated in FIG. As shown in FIG. 5, the first and second correction coefficients K1 and K2 take a value of 0 in the dependency region where the dependency D ranges from 0 to a predetermined value Da (corresponding to the predetermined dependency ratio Dra). In the dependency region exceeding the degree Da, the values of the coefficients K1 and K2 increase as the dependency increases.
[0027]
Then, in the setting unit 52, the first correction amount Δαt is obtained by multiplying the basic target deceleration rate αta by the first correction coefficient K1, and the target deceleration rate αt is obtained by adding this value Δαt to the value αta. Further, the second correction amount ΔTs is obtained by multiplying the basic deceleration start time Tsa by the second correction coefficient K2, and the deceleration start time Ts is obtained by adding this value ΔTs to the value Tsa.
[0028]
In this manner, the first and second correction amounts Δαt and ΔTs increase as the dependency degree D increases. Therefore, as the dependency degree D increases, the deceleration start timing Ts is delayed and the target deceleration rate αt increases.
As a result, when the dependence D on the driving operation of the driver with respect to the automatic brake device becomes high, the deceleration start timing Ts, that is, the operation start timing of the automatic brake device is delayed, so that the driver inevitably performs the braking operation. (Brake pedal depression operation) is started at an appropriate time, and the degree of dependence on the automatic brake device is reduced.
[0029]
If the driver does not start the braking operation by the deceleration start timing Ts despite the deceleration start timing Ts being delayed in this way, the automatic brake device is activated. At this time, the target deceleration αt increases as the deceleration start timing Ts is delayed. Therefore, even when the deceleration start timing Ts is delayed, the safety distance to the preceding vehicle and the obstacle is maintained by the deceleration operation of the automatic brake device. On the other hand, the set value of the deceleration start timing is reset so that the deceleration start timing Ts is further delayed, thereby reducing the dependence on the automatic brake device during subsequent braking.
[0030]
Further, when the dependency degree D exceeds the predetermined dependency degree Da, the setting unit 52 displays a message such as “excessively dependent on automatic braking” on the display device 40 via the display driving unit 54 to pay attention to the driver. Prompt.
As described above, according to the first embodiment, there is provided a driving assistance device configured as an automatic brake device capable of preventing excessive driver dependence.
[0031]
Next, with reference to FIG. 6, the driving assistance apparatus by 2nd Embodiment of this invention is demonstrated.
The driving support device of the second embodiment is configured as an automatic steering device that automatically steers the vehicle so that the vehicle traveling direction matches the traveling lane direction and the vehicle is positioned at the center of the traveling road surface.
[0032]
As shown in FIG. 6, the automatic steering apparatus includes an ECU 50A configured basically in the same manner as the ECU 50 of the first embodiment, and the CCD camera 4, brake switch 29 and wheels described above are provided on the input side of the ECU 50A. A speed sensor 32 (see FIGS. 1 and 2) is connected. Further, the above-described display device 40 (see FIG. 2) and the steering actuator 60 are connected to the output side of the ECU 50.
[0033]
The steering actuator 60 operates the steering system separately from the steering wheel operation (steering operation) by the driver, and can be variously configured.
For example, the steering actuator 60 is constituted by a torque motor, and the torque motor 60 is connected to the steering shaft 104 of the steering system illustrated in FIG. In FIG. 7, reference numeral 105 denotes a planetary gear device that is interposed in the middle of the steering shaft 104, and the ring gear of the planetary gear device 105 is supported by the vehicle body side bracket 111 via the engagement element 110. The pinion 117, the pinion gear 118, and the clutch 116 are connected to the carrier of the planetary gear unit 105. The steering shaft 104 and the steering gear 103 attached thereto constitute an operating part of a steering system together with arms such as a tie rod (not shown).
[0034]
In the configuration described above, steering is performed by generating a steering force in the steering system in accordance with the operation of the steering wheel 102 or the rotation of the torque motor 60 by the driver. Further, when the automatic steering by the torque motor 60 and the manual steering by the driver are performed at the same time, the engagement element 110 slips and the manual steering is preferentially performed.
The ECU 50 includes an image information processing unit 51A that generates deviation information and declination information from an original image (not shown) captured from the CCD camera 4 and sends it to the setting unit 52A. The image information processing unit 51A includes: Similar to that described in Japanese Patent Laid-Open No. 7-81602, an image conversion unit 51B that converts an original image from the CCD camera 4 into a planar view image, and a deviation between the vehicle center and the driving lane center in the image from the planar view image A deviation calculating unit 51C that calculates deviation information W representing the deviation angle, and a deviation angle calculating unit 51D that calculates deviation angle information representing the deviation angle β between the vehicle traveling direction and the traveling lane direction in the same image from a planar view image. ing. The plan view image includes an image of the traveling lane and an image of the vehicle 1 so as to exemplify the outline in the blocks 51C and 51D of FIG.
[0035]
In the setting unit 52A of the ECU 50A, the basic steering angle δa, the basic steering speed δVa, and the basic steering start timing Tδa (all not shown) are calculated based on the vehicle speed information Vs, the deviation information W, and the deviation angle information β, and are dependent on each other. First, second, and third correction coefficients K1, K2, and K3 (not shown) are obtained from a map (not shown) (corresponding to the map of FIG. 5) based on the dependency degree information D from the degree determining unit 55. The correction coefficients K1, K2, and K3 can be obtained in the same manner as the correction coefficients K1 and K2 in the first embodiment, and description of the calculation method is omitted.
[0036]
Next, the setting unit 52A multiplies the basic steering angle δa, the basic steering speed δVa, and the basic steering start timing Tδa by correction coefficients K1, K2, and K3, respectively, to thereby adjust the first, second, and third correction amounts Δδ, ΔδV, ΔTδ (both not shown) is calculated. Then, by adding the correction amounts Δδ, ΔδV, ΔTδ to the basic steering angle δa, the basic steering speed δVa, and the basic steering start timing Tδa, respectively, the target steering angle δ, the target steering speed δV, and the steering start corresponding to the dependency degree D are added. Time Tδ is calculated.
[0037]
Then, the actuator drive unit 53A of the ECU 50 starts steering based on the target steering angle δ, the target steering speed δV and the steering start timing Tδ sent from the setting unit 52 and the actual steering angle δs detected by the steering angle sensor 61. After the time Tδ, the steering actuator 60 is driven and controlled so that a steering force that is steered to the target steering angle δ at the target steering speed δV is generated in the operating portion (steering shaft, steering gear, various arms) of the steering system.
[0038]
According to the automatic steering device of the second embodiment, automatic steering by the steering actuator 60 is performed so that the deviation W between the vehicle center position and the travel lane center position and the deviation angle β between the vehicle travel direction and the travel lane direction are reduced to zero. In this way, it is possible to prevent deviation from the driving lane. In addition, since the steering start timing Tδ and the steering force by the steering actuator 60 are variably set according to the degree of dependence of the driver on the automatic steering device, excessive dependence on the automatic steering device can be prevented.
[0039]
The driving assistance device of the present invention is not limited to the automatic braking device according to the first embodiment and the automatic steering device according to the second embodiment, and can be variously modified. For example, both the automatic braking function and the automatic steering function are provided. It can be configured as an automatic driving device provided or a travel control device that keeps the distance between the host vehicle and the preceding vehicle constant.
Further, even when the driving support device of the present invention is configured as an automatic brake device, it is not essential to configure as in the first embodiment. For example, the operation unit based on the vehicle running state such as the vehicle speed and the dependence degree. The calculation method of the operation start time and the operating force is not limited to the method described in the first embodiment. In addition, another inter-vehicle distance sensor such as an ultrasonic sensor may be used in place of the radio wave radar or the CCD camera, another vehicle speed sensor may be used in place of the wheel speed sensor, and the information providing device is replaced with a display device. It can be configured with a voice-type reporting device.
[0040]
When the driving assistance device of the present invention is configured as an automatic steering device, the vehicle traveling direction and the traveling lane direction are matched and the vehicle center position and the traveling lane center position are matched as in the second embodiment. This is not essential, and can be configured as an automatic steering device that performs a conventionally known lane departure function. Further, a hydraulic actuator may be used as the steering actuator instead of the torque motor of the second embodiment.
[0041]
【The invention's effect】
According to the first aspect of the present invention, the vehicle travel detected by the detecting means and the dependence determined based on the ratio of the actuator driven by the actuator in the driving operation of the driver or the driving of the vehicle actuator by the actuator a plurality of times. Depending on the state, the operation start timing and operating force of the actuator by the actuator are set, so if the driver's degree of dependence on the driving support device is large, By delaying the operation start time, it is possible to increase the probability that the driver will perform the driving operation without waiting for the operation start of the operation part by the actuator when it is necessary to change the vehicle running state thereafter. Excessive reliance on the driver's driving support device can be prevented, and vehicle traveling safety can be improved.
[0042]
According to a second aspect of the present invention, in an automatic brake device including a brake actuator capable of operating the brake system separately from the braking operation by the driver, the braking start timing and the braking force of the brake system by the brake actuator are determined automatically by the driver. Since it sets according to the dependence on a brake device, the excessive dependence on an automatic brake device can be prevented reliably.
[0043]
According to a third aspect of the present invention, in an automatic steering apparatus having a steering actuator capable of operating the steering system separately from the steering operation by the driver, the steering start timing and steering force of the steering system by the steering actuator are determined automatically by the driver. Since the setting is made according to the degree of dependence on the steering device, excessive dependence on the automatic steering device can be prevented.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an automatic brake device according to a first embodiment of the present invention.
FIG. 2 is a schematic block diagram showing an electronic control unit of the automatic brake device shown in FIG. 1 together with peripheral elements.
3 is a flowchart of a target deceleration / deceleration start timing setting routine executed by the electronic control unit shown in FIGS. 1 and 2. FIG.
4 is a diagram illustrating a dependency ratio / dependency map used in the setting routine shown in FIG. 3; FIG.
5 is a diagram illustrating a dependency / correction coefficient map used in the setting routine of FIG. 3; FIG.
FIG. 6 is a schematic block diagram showing an electronic control unit of an automatic steering apparatus according to a second embodiment of the present invention together with peripheral elements.
7 is a schematic view showing a torque motor constituting a steering actuator of the automatic steering apparatus shown in FIG. 6 together with peripheral elements.
[Explanation of symbols]
2 Radio wave radar (detection means)
4 CCD camera (detection means)
12 Throttle actuator 24 Service brake (actuating part)
29 Brake switch 30 Brake actuator 32 Wheel speed sensor 40 Display device (information providing device)
50, 50A Electronic control unit 51 Distance calculation unit 52, 52A Setting unit 53 Vehicle speed control unit (actuator control means)
53A Actuator drive (actuator control means)
54 display driving unit 55 dependency determining unit (dependency determining unit)
60 Steering actuator 102 Steering wheel 103 Steering gear (operation part)
104 Steering shaft (actuator)

Claims (3)

In a vehicle driving support device including an operation unit that changes a vehicle running state according to a driving operation by a driver,
Detecting means for detecting a vehicle running state;
An actuator capable of driving the operating unit separately from the driving operation;
Dependency degree determining means for determining a dependency degree based on a ratio of the actuator being driven by the actuator in a plurality of times of driving of the actuator;
Setting means for setting the operation start timing and the operating force of the operating unit by the actuator according to the vehicle running state detected by the detecting means and the dependency determined by the dependency determining means;
An operation support apparatus comprising: an actuator control unit that drives and controls the actuator so that the operating unit operates with the set operating force from the set operation start time. The driving support device according to claim 1, wherein the actuator includes a brake actuator that drives a brake system as the operating unit. The driving support apparatus according to claim 1, wherein the actuator includes a steering actuator that drives a steering system as the operation unit.

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