JPH05178115A - Dozing driving detecting device - Google Patents

Abstract

PURPOSE:To provide a dozing driving detecting device which can detect dozing operation surely according to differences among individuals regardless of driving roads. CONSTITUTION:A lateral displacement (x), a forward displacement (y), a yaw angle phi to the track direction (lane mark) which are detected by an image sensor 20 and a car velocity v from a car velocity sensor 24 are input to a basic operation pattern analyzing unit 22a of a microcomputer 22. Before five minutes elapses after the state of running, it is regarded as normal operation, and every car velocity is stored in a memory 22b, taking the maximum value of the normal operation as reference. After the lapse of five minutes, a lateral displacement x, a forward displacement y, a yaw angle to the track direction (lane mark) from the image sensor 20 are compared with the stored reference value, and if it exceeds the reference value, the time required until it returns again to the reference value is measured by a timer 22d. The occurrence of dozing at the wheel is detected from the return time and the comparison with a designated time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drowsy driving detection device, and more particularly to a device for detecting a drowsy driving from a change in the position of a vehicle.

[0002]

2. Description of the Related Art Conventionally, a drowsy driving detection device for detecting a drowsy state of a driver has been developed for the purpose of ensuring safety in driving on a highway.

In such a drowsy driving detection device, a configuration is adopted in which the steering angle of a normal vehicle is monitored and a decrease in the driver's consciousness level, that is, a drowsiness is determined from the change in the steering angle.

For example, in the vehicle alarm device disclosed in Japanese Patent Laid-Open No. 60-15230, the steering change is monitored by the vehicle speed detection value and the steering angle detection value, and the steering change pattern exceeds the reference steering change pattern. A configuration for issuing an alarm for wake-up when it is determined that it has been shown is shown.

[0005]

However, in such a configuration in which the drowsy driving is detected from the change in steering, the reference steering pattern is exceeded even when the driver performs normal steering in the awake state on a curved road. There is a high possibility that it will be determined that a drowsy drive has occurred, and therefore there was a problem that it basically only works effectively on a straight track.

Further, the change in the steering angle largely depends on the individual difference of the driver, and there is a tendency that some drivers tend to take a large steering angle even during normal driving. Therefore, the standard may not be set uniquely. There was a problem that it was not versatile enough to handle all drivers.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is a doze driving detection device capable of surely detecting a doze driving on any road regardless of the individual difference of the driver. To provide.

[0008]

In order to achieve the above object, a doze driving detection apparatus according to claim 1 is a position detecting means 1 for continuously detecting a vehicle position with respect to a running road, as shown in FIG. Reference value calculation means 2 for calculating a reference value of the vehicle position during normal operation as a function of vehicle speed, and first comparison means 3 for comparing the vehicle position and a reference value after a lapse of a predetermined time from the start of traveling, When the vehicle position exceeds the reference value, the vehicle position again has a measuring means 4 for measuring a return time when the vehicle position is below the reference value, and a second comparing means 5 for comparing the return time with a predetermined value. It is characterized by

In order to achieve the above object, the drowsiness driving detection apparatus according to a second aspect of the present invention comprises a position detecting means 1 for continuously detecting the vehicle position with respect to the running road as shown in FIG.
A steering angle detecting means 6 for detecting a steering angle of the vehicle; a phase difference calculating means 7 for detecting a time delay of the change of the steering angle with respect to a change of the vehicle position; and a reference time of the time delay during normal operation. Is calculated as a function of the vehicle speed, first comparison means 9 for comparing the time delay after the lapse of a predetermined time from the start of travel with the reference time, and the time delay exceeds the reference time. In this case, the measuring means 1 for measuring the return time at which the time delay again becomes the reference time or less.
0, and second comparing means 11 for comparing the recovery time with a predetermined value.

[0010]

In the drowsy driving detection device according to the first aspect of the invention, not the steering angle of the vehicle but the vehicle position such as the lateral displacement amount or the yaw angle with respect to the running direction (lane mark) is detected, and the vehicle position during normal operation is detected. When the value exceeds the reference value in, the dozing driving is detected by monitoring how long it takes to return to the reference value again. As is well known, the driver always drives by repeating the three steps of recognition, judgment, and operation. However, if the driver's consciousness level decreases, the processing speed in each of the above steps decreases. Therefore, for example, if an abnormal lateral displacement amount of a vehicle is recognized and it is attempted to correct it, it cannot be corrected as quickly as in normal operation, and it takes a long time to make correction in proportion to a decrease in consciousness level. Is coming. In addition, the recognition itself of the lateral displacement and the like is delayed as compared with the time of normal operation.

Therefore, this correction is performed, the time to return to the reference value, that is, the return time is measured, and the drowsy driving can be detected by the increase of the return time.

Note that, unlike the steering angle, the lateral displacement amount and the yaw angle with respect to the running direction (lane mark) are physical quantities indicating the deviation from the normal position of the vehicle regardless of the running road, and therefore the same applies to straight roads and curved roads. Is effective for.

Further, since the reference value is calculated based on the normal driving of the driver, it is possible to make a determination according to the driver.

On the other hand, in the doze driving detection apparatus according to the second aspect, the vehicle position is not compared with the reference value, but the time difference between the vehicle position change and the steering angle change, that is, the phase difference is compared with the reference time. When the time exceeds the reference time, the dozing driving is detected depending on how long the time is corrected to the reference time or less again.

As described above, the driver constantly recognizes, judges, and operates, but when the driver's level of consciousness decreases, the time from recognition to operation becomes long, and accordingly, changes in lateral displacement and the like are recognized. However, the change in the steering angle as a result of the operation based on it also shows a delayed change (that is, the phase difference increases).

Therefore, the dozing driving can be detected in the same manner by detecting the increase in the phase difference and monitoring the time until the phase difference returns to the normal state again.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a doze driving detection apparatus according to the present invention will be described below with reference to the drawings.

First Embodiment FIG. 3 shows a block diagram of the configuration of this embodiment, and FIG. 5 shows a processing flowchart of this embodiment. An image sensor 20 including a CCD camera and an image processor is attached to the rear side of the rearview mirror above the driver's seat as position detecting means. In this image sensor 20, the lateral displacement amount x, the forward displacement amount y, and
The yaw angle φ with respect to the running direction (lane mark) is detected. The detection method can be obtained by a known method, for example, from the position or inclination of the white line in the image. Then, the lateral displacement amount x, the forward displacement amount y, and the yaw angle φ with respect to the traveling direction (lane mark) are input to the basic driving pattern analysis unit 22a configured by the CPU in the microcomputer 22. On the other hand, the vehicle speed v at this time is detected by the vehicle speed sensor 24 and input to the basic driving pattern analysis unit 22a (S10).
1). Note that FIG. 4 illustrates the relationship among the lateral displacement amount x, the forward displacement amount y, and the yaw angle φ.

It is considered that the normal operation is performed from the start of running until 5 minutes have passed, and the basic operation pattern analysis unit 22a
Then, the lateral displacement amount x or the forward displacement amount y or the reference value of the yaw angle φ is calculated. As the reference value, the maximum value or the average value of the data for 5 minutes can be used, but since these data change according to the vehicle speed v, it is necessary to set for each vehicle speed (S103). In this embodiment, the maximum value for 5 minutes is set as the reference value. Then, the reference value for each vehicle speed for 5 minutes after the start of traveling is stored in the memory 22b in the microcomputer 22 as a basic operation map.

Since there is a high possibility that a drowsiness drive will occur after 5 minutes have passed, these reference values and the current lateral displacement amount x, forward displacement amount y, or yaw angle φ detected by the image sensor 20 are determined. The size comparison is performed by the comparator 22c under the same vehicle speed condition (S104). Specifically, the reference value at the vehicle speed is read from the memory 22b according to the vehicle speed from the vehicle speed sensor 24, and the current lateral displacement amount x, the forward displacement amount y, and the traveling direction (lane mark) input to the comparator 22c. ) With respect to the yaw angle φ.

Here, when the driver's consciousness starts to decrease, steering is performed differently from that in normal driving, so that the reference value may be exceeded even under the same vehicle speed condition. For example, when focusing on the amount of lateral displacement, when the driver's consciousness level is sufficiently high, the vehicle travels almost in the center of the driving lane, so the lateral displacement amount x is small, but when the consciousness level begins to decrease, appropriate steering along the driving lane is performed. Is not performed, and the lateral displacement amount x also increases. In this case, the timer 22d starts time measurement, and measures the time until the driver recognizes this abnormal position and returns it to the reference value again (S105). Specifically, when the reference value is exceeded, the CPU sends a set signal to the timer 22d.
To start the operation, and when it returns to the reference value again, the reset signal is supplied to the timer 22d to reset. Then, this reset time is supplied to the comparator 22c. As described above, when the dozing driving occurs, the time required for recognizing the abnormal lateral displacement amount x and the forward displacement amount y and returning them to the original values significantly increases. Therefore,
The return time is compared with a predetermined value (for example, 0.5 seconds at 60 km / h) stored in the memory 22b in advance by the comparator 22c (S106), and if the return time is equal to or longer than the predetermined value, the dozing driving is performed. When it is determined that the alarm has occurred, the alarm 28 is activated (S107). The predetermined value may be set by the driver by himself / herself from a setting SW provided near the driver's seat.

As described above, in the present embodiment, attention is paid to the time until the vehicle deviates from the reference value such as the lateral displacement amount and the forward displacement amount and the time until the vehicle returns, and the returning time increases as the driver's consciousness level decreases. Since the occurrence of drowsy driving is detected by utilizing this, it is possible to reliably detect the drowsy driving regardless of the running path and according to the individual difference of the driver.

Second Embodiment FIG. 6 is a block diagram showing the configuration of the second embodiment of the present invention, and FIG. 7 is a processing flowchart. The difference from the above-described first embodiment is that the image sensor 2
0, a steering angle sensor 30 for detecting the steering angle of the vehicle is further provided in addition to the vehicle speed sensor 24, and the occurrence of a dozing driving is detected based on the relationship between the vehicle position and the steering angle. The image sensor 20 detects the lateral displacement amount x, the forward displacement amount y, and the yaw angle φ with respect to the traveling direction (lane mark), and these data are input to the basic driving pattern analysis unit 22a. Further, the vehicle speed v detected by the vehicle speed sensor 24 and the steering angle of the vehicle detected by the steering angle sensor 30 are also input to the basic operation pattern analysis unit 22a.

From the start of running until the lapse of 5 minutes, the above-mentioned first
It is considered that the normal operation is performed as in the embodiment, and the basic operation pattern analysis unit 22a determines the lateral displacement amount x and the steering angle θ.
Of the forward displacement amount y and the steering angle θ or the yaw angle φ and the steering angle θ.
This phase difference is defined by the time delay between the temporal change in the lateral displacement amount x (or the forward displacement amount y, the yaw angle φ) and the temporal change in the steering angle. FIG. 8 shows the lateral displacement amount x, the forward displacement amount y, the time change of the yaw angle φ and the time change of the steering angle θ with respect to the traveling direction (lane mark). Generally, when the lateral displacement amount x occurs, the driver performs steering in the opposite direction in order to eliminate the lateral displacement amount x. Therefore, the time change x (t) of the lateral displacement amount x and the time of the steering angle θ Since the change T (t) has a phase opposite to that of the change θ (t), and the time T until the driver recognizes the lateral displacement amount x and specifically performs steering is finite, the lateral displacement amount x changes with time. Steering change θ after x (t)
(T) will occur. When the driver's consciousness level is high, the processing time from the recognition of the lateral displacement amount x to the steering is short, and therefore the phase difference T is small, whereas when the driver's consciousness level is lowered, this The phase difference T gradually increases. Therefore, in this embodiment, focusing on the increase in the phase difference T, the dozing driving is detected.

That is, the basic operation pattern analysis unit 22a
Then, the maximum value of these phase differences T during normal operation is calculated as the reference time and stored in the memory 22b (S2).
03). At this time, since the phase difference T changes according to the vehicle speed as in the first embodiment described above, the reference time for each vehicle speed is calculated and stored.

After 5 minutes have elapsed from the start of running, the comparator 22c compares the reference time with the current phase difference T, and the current phase difference T is compared with the reference time as in the first embodiment. If the time exceeds, the timer 22d starts time measurement, and again measures the return time until the phase difference T becomes equal to or less than the reference time (S205). When the driver's consciousness level decreases and drowsiness driving occurs, this recovery time increases, so this recovery time and a preset value stored for each vehicle speed in advance and stored in the memory 22b (for example, 0 at 60 km / h) .8
Second), and when it is equal to or more than this set value, it is determined that a drowsy driving has occurred, and the alarm device 28 is activated (S2
06-S207). Further, a second reference time (second reference time> reference time) is separately set in the comparator 22c, and when the phase difference T exceeds the second reference time, it is determined that the vehicle is dozing driving,
The alarm 28 may be activated.

As described above, in the second embodiment, the lateral displacement amount and the like are recognized (input), and the time difference (phase difference) until the corrective steering is performed according to the lateral displacement amount is the driver's consciousness. Focusing on an increase in accordance with the decrease in the level, the dozing driving is detected, so that the dozing driving is surely detected irrespective of the running path and according to the individual difference of the driver as in the first embodiment described above. You can Further, the drowsiness determination described in both examples is a determination based on a mere reference value, but it is also possible to make a determination based on how many times the determination occurs within a fixed time (for example, 5 minutes).

[0028]

As described above, according to the drowsy driving detection device of the present invention, it is possible to reliably detect the drowsy driving regardless of the running path and according to the individual difference of the driver.
It has the effect of enabling safe driving.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of the present invention.

FIG. 2 is another configuration block diagram of the present invention.

FIG. 3 is a configuration block diagram of an embodiment of the present invention.

FIG. 4 is an explanatory diagram of a lateral displacement amount, a forward displacement amount, and a yaw angle in the same embodiment.

FIG. 5 is a processing flowchart of the embodiment.

FIG. 6 is a configuration block diagram of another embodiment of the present invention.

FIG. 7 is a processing flowchart of the embodiment.

FIG. 8 is a timing chart showing a phase difference of the example.

[Explanation of symbols]

 20 image sensor 22 microcomputer 24 vehicle speed sensor 28 alarm device 30 steering angle sensor

Claims (2)

[Claims] 1. A position detecting means for continuously detecting a vehicle position with respect to a running road, a reference value calculating means for calculating a reference value of the vehicle position during normal operation as a function of a vehicle speed, and after a predetermined time has elapsed from the start of traveling. A first comparing means for comparing the vehicle position with the reference value; and a measuring means for measuring a return time at which the vehicle position again becomes equal to or less than the reference value when the vehicle position exceeds the reference value, A drowsiness driving detection device, comprising: a second comparison means for comparing the return time with a predetermined value. 2. A position detecting means for continuously detecting a vehicle position with respect to a running road, a steering angle detecting means for detecting a steering angle of the vehicle, and a time delay of a change of the steering angle with respect to a change of the vehicle position. Phase difference calculation means, reference value calculation means for calculating the reference time of the time delay during normal operation as a function of vehicle speed, and first comparison for comparing the time delay after a lapse of a predetermined time from the start of travel with the reference time. Comparing means, measuring means for measuring a return time at which the time delay again becomes equal to or less than the reference time when the time delay exceeds the reference time, and second comparing means for comparing the return time with a predetermined value And a drowsiness driving detection device.