JPH07205676A - Detection device for dozing at a wheel - Google Patents

Abstract

PURPOSE:To provide a detecting device for the dozing at a wheel which detects the dozing at a wheel of a driver speedily and surely, by using the steering angle of a vehicle. CONSTITUTION:The data of a car speed sensor 10 and a steering angle sensor 12 is outputted into a calculating device 14. The correction coefficient depending on the car speed is stored in a memory device in the calculating device 14, and the corrected steering cycle detected by using the correction coefficient is conversion-calculated to the corrected steering cycle at the standard car speed (e.g. 80km/h). The obtained corrected steering cycle is successively stored into a memory 16, and the average value of a prescribed number of newest data is calculated and compared with the standard cycle in a judging device 18. When the value is larger than the standard cycle, an alarm device 20 is operated.

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 state from a driver's corrected steering cycle.

[0002]

2. Description of the Related Art Conventionally, a drowsy driving detection device for detecting a drowsy state of a driver has been developed in order to ensure safety in driving on a highway. In this type of drowsiness 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, that is, a drowsiness is determined from the change in the steering angle.

However, for example, if it is detected that the steering wheel has turned by a certain angle and the turning signals are integrated to determine whether or not the vehicle has fallen asleep, the driver may perform a normal steering operation on a curved road. Even if you do, there is a possibility that it will be determined to be a dozing driving, therefore,
Basically, there was a problem that it was effective only on a straight track.

Therefore, the applicant of the present application has previously filed Japanese Patent Application Laid-Open No. 5-58.
In Japanese Patent Laid-Open No. 192, there is proposed a configuration in which a driver's correction operation cycle is detected for each vehicle speed band and compared with a reference steering cycle to detect drowsy driving.

[0005]

Here, when the corrected steering cycle is detected for each vehicle speed band, the steering data varies even in the same consciousness state, and therefore an average value of a predetermined number of steering data in the vehicle speed band is calculated. Smoothing and obtaining the corrected steering cycle, it takes time to collect steering data in a specific vehicle speed range in a traveling environment where the vehicle speed changes greatly, and thus it is difficult to detect the corrected steering cycle for every vehicle speed range. In addition, there was a problem that the drowsiness judgment was lost in real time.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a doze driving detection apparatus which can detect the dozing state of a driver quickly and reliably.

[0007]

In order to achieve the above object, a doze driving detection apparatus according to claim 1 is a dozing driving detection apparatus for detecting the dozing state of the driver based on the corrected steering cycle of the driver. The vehicle speed detecting means, the steering angle detecting means, the correction steering cycle detecting means for detecting the correction steering cycle from the detected steering angle data, and the predetermined correction coefficient depending on the vehicle speed are used for the detected correction steering cycle. The present invention is characterized by further comprising a calculating means for correcting to a reference correction steering cycle at a reference vehicle speed and a judging means for detecting a dozing state based on the reference correction steering cycle.

In order to achieve the above object, the drowsy driving detection device according to a second aspect of the present invention is a drowsy driving detection device for detecting the drowsy state of the driver based on the corrected steering cycle of the driver, and detecting the vehicle speed. Means, a steering angle detection means, a correction steering cycle detection means for detecting a correction steering cycle from the detected steering angle data, and a reference cycle according to the detected correction steering cycle and the detected vehicle speed, It is characterized by having an evaluation means for evaluating the awakening level of the person, a calculation means for calculating an average value of a predetermined number of evaluation results, and a determination means for detecting a dozing state based on the calculated average value.

[0009]

According to the dozing driving detection device of the present invention, when the correction steering cycle at a certain vehicle speed is detected, instead of detecting the correction steering cycle at each vehicle speed range, the correction steering cycle is corrected at the reference vehicle speed. Correct to. The correction is performed using a predetermined correction coefficient that depends on the vehicle speed. This correction coefficient is obtained from the statistics of the corrected steering cycle of many drivers, and generally shows that the corrected steering cycle decreases as the vehicle speed increases. The correction coefficient is shown as a ratio when the corrected steering period at a predetermined vehicle speed (reference vehicle speed) is 1. Therefore, when the correction steering cycle at a certain vehicle speed is detected, the reference correction steering cycle at the reference vehicle speed can be calculated by dividing the correction steering cycle by the correction coefficient. By determining whether or not to fall asleep using this reference correction steering cycle, for example, when determining whether or not to fall asleep by comparing the average value of a predetermined number of reference steering cycles with the reference period, It can be collected immediately and can quickly detect dozing driving.

In the dozing driving detection device according to the second aspect,
Although the dozing driving is determined by comparing with the reference steering cycle for each vehicle speed range as in the conventional method, the correction steering cycle is not detected by calculating the average of a predetermined number of steering angle data, but the correction steering cycle detected each time. (Corrected steering cycle without smoothing)
Is compared with the reference period. Then, an average of a predetermined number of the evaluation results of the driver's consciousness level obtained by comparison is calculated and smoothed to determine whether or not the driver is dozing. According to this, it is not necessary to collect a predetermined number of steering angle data for each vehicle speed band, but it is sufficient to collect a predetermined number of evaluation results in all vehicle speed bands, so that the dozing state can be detected more quickly than in the past.

[0011]

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

First Embodiment FIG. 1 is a block diagram showing the configuration of this embodiment. A vehicle speed sensor 10 is provided as vehicle speed detecting means, and a steering angle sensor 12 is provided as steering angle detecting means. As the steering angle sensor 12, for example, a slit plate press-fitted into the steering shaft and two sets of photointerrupters attached to the column tube can be used, and the photointerrupter is shielded by the slit plate as the steering shaft rotates. The turning direction and the turning angle of the steering wheel can be detected by turning on and off by turning the steering wheel off.

Detection signals from the vehicle speed sensor 10 and the steering angle sensor 12 are output to the arithmetic unit 14. Arithmetic unit 1
Reference numeral 4 includes a steering cycle detector, a corrector, an average calculator, and a correction coefficient storage device. The steering cycle detector includes a differentiator, detects an inversion steering point of time-series steering angle data, and detects a time interval between the points as a corrected steering cycle. In addition to using a differentiator as the steering cycle detector, the steering angle data for a predetermined time is measured, and if the time change pattern of the steering angle matches the reference pattern specific to the steering cutback, the steering cutback is determined. It may be determined that there is. The corrector corrects the corrected steering cycle detected by using the below-described correction coefficient stored in the correction coefficient storage device to the corrected steering cycle at the reference speed (for example, 80 km / h). The corrected steering period obtained by the correction is stored in the memory 16. In the memory 16, a predetermined number of corrected correction steering cycles are sequentially stored, and when the predetermined number is stored, they are sequentially updated with the latest corrected correction steering cycle.
Therefore, the memory 16 always stores the latest predetermined number of corrected corrected steering periods. After a predetermined number (for example, 40 steering) of corrected corrected steering cycles are stored in the memory 16,
These data are output to the average calculator in the arithmetic unit 14 and the average value is calculated. The calculated average value is the judgment device 1
8 is output.

The judging device 18 is constituted by including a comparator, and compares the average corrected steering cycle supplied from the arithmetic unit 14 with a reference steering cycle at a reference vehicle speed (for example, 80 km / h) which is obtained in advance. , Evaluate the driver's awareness level. As a result of the comparison, when it is determined that the dozing driving is occurring, an alarm signal is output to the alarm device 20 to generate an alarm and wake up the driver.

FIG. 2 shows the correction coefficients stored in the correction coefficient storage device of the arithmetic unit 14. In the figure, the horizontal axis represents the vehicle speed (km / h) and the vertical axis represents the corrected steering correction coefficient. The correction coefficient is obtained from the statistics of the data of the corrected steering cycle according to the vehicle speeds of many drivers.Although the absolute value of the corrected steering cycle increases or decreases depending on the driver, the tendency for the vehicle speed tends to be almost constant. Show. Figure 2
In the above, the correction coefficient is a ratio when the corrected steering cycle at a vehicle speed of 80 km / h is set to 1. This correction coefficient is a coefficient that can be applied to almost all drivers regardless of individual drivers. The correction coefficient storage device stores the correction coefficient shown in FIG. 2 as a map or as a function, and outputs the correction coefficient at the current vehicle speed detected by the vehicle speed sensor 10 to the corrector of the arithmetic unit 14 to detect it. The corrected steering cycle thus obtained is corrected to the corrected steering cycle at the reference vehicle speed of 80 km / h. The correction method is performed by dividing the detected corrected steering cycle by a correction coefficient.

FIG. 3 shows a flowchart of the processing in this embodiment. First, when the vehicle speed data and the steering angle data from the vehicle speed sensor 10 and the steering angle sensor 12 are input to the arithmetic unit 14, the arithmetic unit 14 detects the corrected steering cycle from the time-series steering data and stores it together with the vehicle speed data at that time. It is stored in the device (S101). Then, the corrected steering cycle detected using the correction coefficient shown in FIG. 2 stored in the storage device in the arithmetic unit 14 is set to 80 km.
It is corrected to the corrected steering cycle at / h (S102). Specifically, the correction steering cycle stored in the storage device is read together with the vehicle speed data, the correction coefficient corresponding to the vehicle speed is read from the storage device, and the correction steering cycle at 80 km / h is calculated from the correction steering cycle / correction coefficient. To do. The corrected steering cycle thus calculated is sequentially stored in the memory 16, and the latest 40 steering portions are stored while being updated (S103). After the latest 40 steering correction cycles are stored in the memory 16, these data are output to the average calculator in the arithmetic unit 14 to calculate the latest 40 steering average steering cycles (S104). This average calculation is started at the time when the data for the latest 40 steering wheels are obtained, and thereafter, new corrected steering cycle data is input and is calculated each time the data is updated. The calculated average corrected steering cycle is output to the determiner 18, and the magnitude is compared with the reference cycle during normal operation at a predetermined 80 km / h (S105). As a result of the comparison, when it is determined that the average correction steering cycle is larger than the reference cycle by the predetermined amount, the correction steering cycle is increased because the driver's consciousness level is lowered, that is, the driver operates the steering frequently. It is determined that the alarm has disappeared, and the alarm device 20 is activated to generate an alarm (S106).

As described above, in this embodiment, the average correction steering cycle is not detected for each vehicle speed zone, but the correction steering cycle detected at an arbitrary vehicle speed is used as the reference vehicle speed (80 km / h).
Since it is converted into the corrected steering cycle in step S1, and the average is calculated and compared with the reference cycle, the time until the drowsiness determination is made can be extremely short, and the average of the predetermined number updated in the sequentially detected corrected steering cycle is calculated. Since it is calculated and compared with the reference period, it is possible to detect the driver's lowered consciousness, that is, the dozing driving in real time.

In this embodiment, the reference vehicle speed is 80k.
Although m / h is used, it goes without saying that another vehicle speed can be used as the reference vehicle speed.

In this embodiment, an alarm is issued when a drowsy driving is detected. Of course, the judging device 18 outputs a control signal to a brake actuator or the like to control the running of the vehicle. Is also possible.

Further, the comparison result in the judging device 18 is evaluated by the level, and the level is divided into 10% larger than the reference period, 20% larger than the reference period, and the like, and an alarm is generated according to the level (for example, the volume of the alarm or You can also change the type of alarm). In short, it is possible to take various drowsy driving prevention measures within the scope of the idea of the present invention.

Second Embodiment FIG. 4 shows a processing flowchart of the second embodiment of the present invention. The configuration of the present embodiment is the first shown in the schematic FIG.
The configuration is the same as that of the embodiment, and the vehicle speed data and the steering angle data obtained by the vehicle speed sensor 10 and the steering angle sensor 12 are output to the arithmetic device 14, and a predetermined arithmetic processing result is performed and output to the determiner 18. It The judgment device 18 compares the input calculation result with the reference value, and activates the alarm device 20 according to the comparison result.

However, in this embodiment, unlike the first embodiment, the arithmetic unit 14 has a steering cycle detector, a comparator, a storage device, and an average calculator, and the storage device normally stores the data collected in advance. The reference cycle for each vehicle speed zone during operation is stored. Then, the detected correction steering cycle and the reference cycle in the vehicle speed range in which the correction steering cycle is detected are input to the comparator, and the magnitude comparison of both cycles is performed. The comparison result is stored in the memory 16. After a predetermined number of comparison results are stored in the memory 16, these data are output to the average calculator, averaged and output to the determiner 18. The result obtained by comparing the magnitudes by the comparator is the magnitude comparison result of the corrected steering cycle detected each time and the reference cycle.Since there is variation in the detected correction steering cycle, the magnitude comparison result also varies. Is happening. Therefore, smoothing is performed by averaging a predetermined number of magnitude comparison results.

The details of the processing of this embodiment will be described below with reference to FIG. First, the vehicle speed sensor 10 and the steering angle sensor 1
When the vehicle speed data and the steering angle data from 2 are input to the arithmetic unit 14, the arithmetic unit 14 detects the corrected steering cycle from the time-series steering data and stores it in the storage unit together with the vehicle speed data at that time (S201). Then, the reference period in the vehicle speed zone to which the stored vehicle speed of the corrected steering period belongs is read from the storage device, and the comparator compares the corrected steering period with the reference period. The comparison result is evaluated by dividing it into several levels and is output to the memory 16 (S202). In order to divide into several levels, level 1, level 2, level 3, etc. may be set according to the difference amount between the corrected steering cycle and the reference cycle. The evaluation results evaluated at several levels are sequentially stored in the memory 16,
The latest 40 steering evaluation results are stored while being updated (S203). Memory 16 with the latest 40 steering evaluation results
Then, these data are output to the average calculator in the arithmetic unit 14 and the average evaluation results of the latest 40 steering wheels are calculated (S204). This average calculation is started when the evaluation result data for the latest 40 steering wheels is obtained, and thereafter, new evaluation result data is input and calculated every time the data is updated. The calculated average evaluation result is output to the determiner 18 and compared with a predetermined reference value during normal operation (S205). As a result of the comparison, when it is determined that the average evaluation result indicates the consciousness lowering level, the alarm device 20 is activated to generate an alarm (S20).
6).

As described above, in this embodiment, the average corrected steering period is not calculated for each vehicle speed band, but the detected corrected steering period and the reference period are compared and evaluated each time, and a predetermined number of evaluation results are calculated. Since drowsiness driving is detected by calculating and smoothing the average, the time until the drowsiness determination can be made extremely short, and further, the average of a predetermined number of updated evaluation results is calculated and determined. Therefore, the driver's consciousness lowering state, that is, the dozing driving can be detected in real time.

Although the embodiments of the present invention have been described above, it should be additionally noted that the present embodiments include the following embodiments in addition to the technical matters described in the claims.

(1) The dozing driving detection apparatus according to claim 1, wherein the correction coefficient is indicated by a ratio of the corrected steering cycle at each vehicle speed when the corrected steering cycle at the reference vehicle speed is 1. Detection device.

(2) The drowsiness driving detection device according to claim 2, wherein the evaluation means evaluates the driver's consciousness level at a level that can take a plurality of values.

[0028]

As described above, according to the drowsy driving detection device of the present invention, it is possible to detect the dozing state of the driver quickly and reliably based on the steering angle of the vehicle. Therefore, when the doze driving detection device of the present invention is incorporated into a vehicle safety system, the reliability and effectiveness of the system can be significantly improved.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of a correction coefficient according to the same embodiment.

FIG. 3 is a processing flowchart of the embodiment.

FIG. 4 is a processing flowchart of another embodiment of the present invention.

[Explanation of symbols]

 10 Vehicle speed sensor 12 Steering angle sensor 14 Computing device 16 Memory 18 Judgment device 20 Alarm device

Claims (2)

[Claims] 1. A doze driving detection device for detecting a driver's dozing state based on the driver's corrected steering cycle, the vehicle speed detecting means, the steering angle detecting means, and the corrected steering cycle based on the detected steering angle data. A correction steering cycle detecting means for detecting the correction steering cycle, a calculating means for correcting the detected correction steering cycle to a reference correction steering cycle at a reference vehicle speed using a predetermined correction coefficient depending on the vehicle speed, and a doze based on the reference correction steering cycle. A dozing driving detection device, comprising: a determination unit that detects a state. 2. A doze driving detection device for detecting a driver's dozing state based on the driver's corrected steering cycle, the vehicle speed detecting means, the steering angle detecting means, and the corrected steering cycle based on the detected steering angle data. The correction steering cycle detecting means for detecting the, the evaluation means for comparing the detected correction steering cycle with the reference cycle corresponding to the detected vehicle speed, and evaluating the awakening level of the driver, and the average value of a predetermined number of evaluation results A drowsiness driving detection device, comprising: a calculation unit that calculates a drowsiness state and a determination unit that detects a dozing state based on the calculated average value.