JP3799780B2 - Doze driving detection device - Google Patents

Description

BACKGROUND OF THE INVENTION
The present invention relates to a snooze driving detection device, and more particularly to a device for detecting a driver's snoozing driving in a vehicle.
[0001]
In recent years, safety awareness of drivers has increased, and safety devices that prevent accidents are being developed. Among them, since a snooze driving accident occurs once the human and physical damage increases, a snooze driving detection device is particularly desired to prevent it.
[0002]
[Prior art]
As a conventionally known drowsy driving detection device, there is a method for detecting the characteristics of the steering pattern of the steering wheel.
[0003]
For example, in the drowsy driving detection device disclosed in Japanese Patent Application Laid-Open No. 52-25336, when the state of arousal level is low, the driver's steering wheel operation is reduced and becomes messy, and minute correction steering is not performed. Take advantage of the trend. That is, the deviation frequency of the steering wheel steering angle with respect to a predetermined reference angle is detected, and this is compared with the frequency expected at the normal time to determine whether it is normal driving or dozing driving.
[0004]
In addition, the yaw direction angular velocity sensor that detects the yaw direction (yaw) angular velocity (yaw rate) of the vehicle is used, and the change frequency is similarly obtained from the detection signal of the yaw direction angular velocity detected by the yaw direction angular velocity sensor. A snooze driving detection device for determining driving is also known.
[0005]
[Problems to be solved by the invention]
The detection accuracy of such a drowsy driving is related to the drowsy driving detection sensitivity of the sensor used and the robustness against noises such as disturbances. There may be a problem that an alarm (false alarm) occurs even though the vehicle is not in operation.
[0006]
This occurs because the steering angle of the steering wheel and the angular velocity in the yaw direction are indicators that are greatly influenced by the traveling environment.
[0007]
In particular, there is a high frequency of false alarms near the entrance of the tunnel. This is because the steering angle of the steering wheel and the angular velocity of the yaw direction change depending on human physiological and psychological factors.
[0008]
Among them, a physiological factor is that a certain amount of time is required for the adaptation of the eye function to light and dark. This can be observed as a phenomenon in which when eyes suddenly enter a dark tunnel, their eyes are not used for a while and things cannot be seen well. The same phenomenon occurs to a small degree when going out from a dark tunnel to a bright place. The deterioration of the visibility at this time changes the steering wheel operation of the driver.
[0009]
Psychological factors are due to deterioration of the visibility, feeling of pressure received from the side walls, fear of fear, and the like. This also changes the driver's steering wheel operation.
[0010]
If the number of such false alarms is too great, the reliability of the device will be significantly reduced, and there is a risk that it will be useless in a critical situation. Therefore, the reduction of false alarms is indispensable for improving the accuracy of the detection device.
[0011]
As a method of reducing false alarms, it is possible to reduce the sensitivity of drowsy driving detection (make it dull) and make it difficult to issue an alarm, but then it will be safe because detection will be delayed or leaked when you are actually falling asleep. There is a problem above.
[0012]
Thus, the problem of false alarm and detection sensitivity is in a trade-off relationship, and it is difficult to satisfy both at the same time.
[0013]
Therefore, in view of the above-described problems, an object of the present invention is to provide a drowsiness detection device that reduces false alarms near the tunnel entrance without reducing detection sensitivity.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, as shown in principle in FIG. 1, the dozing operation detection device 1 according to the present invention recognizes the steering angle detection means 2 of the steering wheel and the entry and advance of the tunnel. A tunnel approach / advance determination means 3 for determining whether or not the dozing operation is not performed for a predetermined time immediately after the tunnel entry / advance determination means determined by the tunnel entry / advance determination means. Yes.
[0015]
That is, the drowsy driving detection apparatus 1 determines the awakening level in accordance with, for example, the change frequency of the steering angle of the steering wheel as described above, but the information obtained from the tunnel entry / advance determination means 3 is used to enter the tunnel. If the driver indicates that the advance has been recognized, the determination of the arousal level, that is, the determination operation of the dozing operation is interrupted.
[0016]
After this interruption, as in the conventional case, when the change frequency of the steering angle falls below a threshold value that is a criterion for determining the arousal level corresponding to the change frequency, it may be determined that the vehicle is dozing.
[0017]
That is, the operation frequency (rotation angle change frequency) representing the accuracy of the steering operation is calculated from the steering angle detection signal by the steering angle detection means 2, and when attention is paid to the temporal change, the operation frequency is high in the awake state and the doze driving Then, the operation frequency decreases.
[0018]
In the drowsy driving detection apparatus according to the present invention, as shown in FIG. 2, a yaw direction angle detection means 4 may be used instead of the steering angle detection means 2 of the steering wheel shown in FIG.
[0019]
In this case, if the information obtained from the tunnel entry / exit determination means 3 indicates that the driver has recognized the entry / exit into the tunnel, the dozing operation detection device 1 is awakening degree based on the yaw angular velocity. That is, the determination operation of dozing operation is interrupted.
[0020]
Then, after the interruption, when the change frequency of the yaw direction angular velocity is used instead of the steering angle, and falls below a threshold value that is a criterion for determining the arousal level corresponding to the change frequency, it is determined that the driver is dozing. That's fine.
[0021]
That is, from the angular velocity detection signal from the yaw direction angular velocity detection means 4, the dozing driving detection device 1 calculates the yaw direction angular velocity change frequency representing the stability of the vehicle, and paying attention to this temporal change, the change frequency in the wakefulness state. Although it can be predicted that the vehicle is traveling in response to a change in the road shape accurately, it can be predicted that the vehicle is traveling dangerously because the frequency of the change decreases in the drowsy driving state.
[0022]
In addition, as said tunnel approach / advance determination means 3, operation SW of the headlamp of a vehicle can be used.
[0023]
Further, instead of interrupting the drowsy driving determination operation, the sensitivity at the time of the determination may be changed to make it difficult to issue an alarm, and as a result, a similar effect may be obtained.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 shows an embodiment of the drowsy driving detection apparatus according to the present invention shown in FIG. 1, in which the steering angle sensor 2 is used as the steering angle detection means and the vehicle is used as the tunnel entry / advance determination means. The headlamp operation switch 3 is used.
[0025]
In other words, as a method of detecting entry / exit into the tunnel, a method using a radio wave or sound wave type distance measuring means attached to the upper surface of the vehicle can be considered, but it is not possible to know whether the driver is awake or doze. Therefore, if you are asleep and you are driving asleep, the detection will be missed, which is very dangerous.
[0026]
In addition, it is possible to detect entering and advancing into a tunnel using an automatic light that has been put into practical use as a system that automatically turns on when it is determined that it is dark using the output of the illuminance sensor. There is.
[0027]
Therefore, in this embodiment, as a method of detecting entry / exit into the tunnel, it is performed based on whether the vehicle headlight operation switch has been operated (whether the driver has recognized entry / exit into the tunnel). . The fact that the operation switch has been operated can be considered as proof that the driver is surely awake at the same time that the entry or advance of the tunnel can be specified. Therefore, even if the dozing operation determination is interrupted for a predetermined time immediately after this, there is no possibility that detection of the dozing operation will be missed.
[0028]
FIG. 4 shows an embodiment of the snooze driving detection apparatus according to the present invention shown in FIG. 2, wherein here the yaw direction angular velocity sensor 4 is used as the yaw direction angular velocity detection means and the tunnel approach / advance determination means. The vehicle headlamp operation switch 3 is used. The operation is the same as in the embodiment of FIG.
[0029]
FIG. 5 shows an example of a calculation processing flow executed by the dozing operation detection device 1 in the embodiment shown in FIGS. 3 and 4. Hereinafter, the operation of the embodiment will be described with reference to this flow. explain.
[0030]
First, the detection signal output from the sensor 2 or 4 is captured (step (1)).
[0031]
Next, it is determined whether the vehicle has entered or advanced into the tunnel (step (2)). This is determined by whether or not the operation switch 3 of the vehicle headlamp has been operated. That is, the previous position of the operation switch and the current position of the operation switch 3 are compared. If they are different, it can be regarded that the operation switch has been operated.
[0032]
Next, the built-in timer t measures the time from the moment of entering or advancing into the tunnel (step (3)).
[0033]
It is determined whether the timer time t has passed a predetermined time T (for example, 30 seconds) that is considered to be the completion of the light / dark adaptation of the driver's eye function (t> T) (step {circle around (4)}). Until the time T elapses (t ≦ T), the doze driving determination is not performed.
[0034]
Thereby, the misjudgment of the dozing operation at the time of entering / exiting a tunnel can be reduced.
[0035]
When t> T, it is considered that the light / dark adaptation of the eye function has been completed, and the drowsy driving determination data X is calculated (step (5)). That is, in the case of the steering angle sensor 2, operation frequency (steering angle change frequency) data X representing the accuracy of the steering operation is calculated from the steering angle detection signal.
[0036]
The calculated dozing operation determination data X is compared with a preset threshold value S to make a dozing operation determination (step {circle around (6)}). Therefore, in the case of the steering angle change frequency, the operation frequency is low in the dozing state, and X <S and it is determined that the driving is a dozing operation (step (7)), but when it is determined that X ≧ S, the operation frequency is high. Is determined to be awake driving (step (8)).
[0037]
The dozing operation alarm using changes in the steering angle and the yaw angular velocity is a well-known technique, and therefore the description thereof is omitted here.
[0038]
In step {circle around (2)}, when the operation switch 3 is not operated, the timer t is reset (step {circle around (9)}).
[0039]
【The invention's effect】
As described above, according to the drowsy driving detection apparatus according to the present invention, the determination operation of the arousal level with respect to the steering angle of the steering wheel or the angular velocity of the yaw direction is performed until a predetermined time immediately after entering the tunnel or entering the tunnel. Since it has been configured so that there is no reduction in the detection sensitivity of the drowsy driving, it is possible to reduce false alarms and thus increase the detection accuracy of the drowsy driving.
[Brief description of the drawings]
FIG. 1 is a block diagram showing in principle a dozing operation detection device (1) according to the present invention.
FIG. 2 is a block diagram showing in principle a dozing operation detection device (2) according to the present invention.
FIG. 3 is a block diagram showing an embodiment of a snooze driving detection device (1) according to the present invention.
FIG. 4 is a block diagram showing an embodiment of a snooze driving detection device (2) according to the present invention.
FIG. 5 is a flowchart of a program executed in the drowsy driving detection apparatus according to the present invention.
[Explanation of symbols]
1 Dozing operation detection device 2 Steering angle sensor (steering angle detection means)
3 Headlamp operation switch 4 Yaw direction angular velocity sensor (Yaw direction angular velocity detection means)
In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (4)

In the drowsy driving detection device for determining the drowsy driving based on the steering angle of the steering wheel of the vehicle detected by the steering angle detecting means,
Tunnel entry / exit determination means for determining whether or not the driver has recognized entry / exit into the tunnel is further provided, and only for a predetermined time immediately after the tunnel entry / exit determined by the tunnel entry / advance determination means. A dozing operation detection device characterized by not performing a determination of dozing operation. In the dozing operation detection device that determines the dozing operation based on the yaw direction angular velocity of the vehicle detected by the yaw direction angular velocity detection means,
Tunnel entry / exit determination means for determining whether or not the driver has recognized entry / exit into the tunnel is further provided, and only for a predetermined time immediately after the tunnel entry / exit determined by the tunnel entry / advance determination means. A dozing operation detection device characterized by not performing a determination of dozing operation. In claim 1 or 2,
The dozing operation detection device, wherein the tunnel entry / exit determination means is an operation SW of a vehicle headlamp. In any one of Claims 1 thru | or 3,
A dozing operation detection device, wherein the sensitivity of the dozing operation determination is changed for the predetermined time.

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