JPS6117691B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drowsy driving determination device, and more particularly to a drowsy driving determination device that determines a drowsy driving situation that occurs during monotonous driving on a highway or the like and issues a warning to the driver.

In order to prevent drowsy driving during monotonous driving on expressways, etc., there is a method of giving a warning to the driver at regular intervals and requesting the driver to respond by pressing a reset button in response to the warning. Proposed. However, since these methods issue a warning at regular intervals, it cannot be said that they issue a warning when no warning is needed or accurately determine whether the driver's driving ability has deteriorated.

The present invention has been made in view of the above,
By determining the decline in the driver's control ability,
This system provides a drowsy driving determination device that accurately detects drowsiness and issues a warning to the driver, and its configuration is such that when monotonous driving continues for a predetermined period of time, a predetermined frequency is detected. Alternatively, a reference sound generation circuit that generates a reference sound with an amplitude, and a control sound that generates a control sound whose frequency or amplitude changes under the driver's control when the reference sound is generated or after a certain period of time has elapsed since the generation of the reference sound. a generation circuit; a first determination circuit that outputs an output when a difference in frequency or amplitude between the control sound controlled by the driver and the reference sound is smaller than a predetermined setting value; and the determination circuit. a second determination circuit that operates when the output time exceeds a predetermined set time; and a second determination circuit that does not output within a predetermined time after the reference sound is generated. and an alarm device activation circuit that outputs an alarm signal at certain times.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 through 6A and 6B.

FIG. 1 shows a block diagram of an embodiment of the present invention, which includes a monotonous operation detection device 1, a reset prevention circuit 1', a reset circuit 1'', and a reference sound generation circuit 2.
, a control sound generation circuit 3, a first determination circuit 4,
It includes a time setting circuit 5, a second determination circuit 6, an alarm device activation circuit 7, and an alarm device 7'.

The monotonous driving detection device 1 detects monotonous driving conditions determined in advance, such as when the shift switch is in the 4th or 5th speed, when the brake switch is not activated, when the vehicle speed signal indicates a high speed, etc. If the operation continues for more than a set time, it is detected as a monotonous operation and a monotonous operation signal is output. For example, when the driver is tasked with control work by outputting a signal to the driver, the reset circuit 1'' is activated and the generation of the reference sound and control sound is stopped because the monotonous driving signal is no longer output by operating the shift lever. and also prevent
The reset circuit 1'' resets the monotonous operation detection device 1, reference sound and control sound generation circuit when the control work by the driver or the activation of the alarm 7' is completed, or when a predetermined period of time has elapsed after the monotonous operation state has ended. 2 and 3. The reference sound generation circuit 2 generates a reference sound in response to a monotonous driving signal, and the control sound generation circuit 3 generates a control sound whose frequency changes depending on the driver's control work. The control task assigned to the hands is to change the frequency of the control sound over a predetermined period of time to keep the deviation of the control sound from the reference sound within a predetermined setting range. A decrease in the driver's driving ability, that is, drowsiness, is detected based on the control ability in the control work.The first judgment circuit 4 detects the deviation of the control sound controlled by the driver from the reference sound by the above-mentioned setting. The time setting circuit 5 determines whether it is within the range.
is turned on (ON) by the operation of the reference sound and control sound generation circuits 2 and 3, and is turned off (ON) when a predetermined set time elapses or when the driver completes the control work within that time. OFF), and the second determination circuit 6 determines whether the control work by the driver has been completed within the time set by the time setting circuit 5. When the second determination circuit 6 determines that the driver is unable to perform the control work, the alarm activation circuit 7 is activated in response to the signal, and the alarm 7' issues an alarm.

FIG. 2 shows a circuit configuration corresponding to the block diagram in FIG. The reference sound generation circuit 2 is activated by the output of the timer 9 and has a constant frequency generator connected to a speaker 13 that emits the reference sound. The control sound generation circuit 3 is activated by the output of the timer 9 and includes a variable frequency oscillator 14a connected to a speaker 15 that emits the control sound, and a variable resistor that is operated by the driver to change the frequency of the oscillator 14a. 14b, and the first determination circuit 4 includes a bandpass filter 17 that passes a control sound within a set range with a deviation (frequency difference) from the reference sound, and a bandpass filter 17 whose output is predetermined. set value
Comparison circuit 1 that outputs for a time period exceeding V ₁
8, the time setting circuit 5 is turned on by the output of the timer 9, and a reset signal 31 is output from the reset circuit 1'' when a certain set time has elapsed or when the control work is completed within that time. The second determination circuit 6 includes an integrating circuit 19 that integrates the output of the comparator circuit 18 and a timer 16 that is turned off when the comparator circuit 18 is turned off.
an inverter 20 that resets the integrating circuit 19 by a comparator 21 that outputs an output when the integral value of the integrating circuit 19 reaches a predetermined set value _V2 ;
AND circuit 22 which receives the output of
The alarm device activation circuit 7 has a pulse generation circuit 24 that generates a pulse at the falling edge of the output of the timer 16, and receives the outputs of the pulse generation circuit 24 and the inverter 23.
The AND circuit 25 receives the output of the AND circuit 25 and turns on (ON) for a certain set time to turn on the alarm (buzzer).
Monostable multivibrator 26 operating 27
It has The reset circuit 1'' also receives the output of a pulse generation circuit 28 which generates a pulse at the falling edge of the output of the monostable multivibrator 26, the output of an AND circuit 22, the output of the pulse generation circuit 28, and the output of an AND circuit 30, which will be described later. The reset prevention circuit 1' has an OR circuit 11, and the reset prevention circuit 1'
It has an AND circuit 30 that receives outputs of 0 and 29,
When a shift change occurs during detection of monotonous operation, each circuit is reset, but once the timer 9 outputs the reference sound and control sound, it is operated so as not to be reset until the control work is completed.

In the above configuration, the operation will be explained using the time chart shown in FIG. When the time t has elapsed, the timer 9 outputs a monotonous operation signal. The timer 16 outputs the signal 16 for a predetermined set time T by the output of the monotonous operation signal 9, and the constant frequency oscillation circuit and the variable frequency oscillators 12, 14a output the signal 12, 14a.
Output. A bandpass filter 17 that passes a control sound having a frequency difference within an allowable range with respect to a reference sound outputs the control sound controlled by the driver as a signal 17, and a comparison circuit 18 outputs the control sound controlled by the driver as a signal 17. Signal 18 compared to and exceeding the set value V ₁
is output, and the integration circuit 19 integrates the signal 1 until it is reset by turning off the signal 18.
Outputs 9. When signal 19 reaches a predetermined set value V ₂ , comparator 21 triggers pulse 2
1 is output, indicating that the aforementioned control work has been completed within the set time T (that is, indicating that no drowsy driving is being performed). The AND circuit 22 outputs the signal 22 based on the pulse 21 and the timer signal 16, which is output from the OR circuit 11 as a reset signal 31, and the timer 9, constant frequency oscillation circuit 12, and variable frequency oscillator 14a are reset. When the timer signal 16 falls, the pulse generation circuit 2
4 outputs pulse 24, but inverter 2
3 does not output, so the alarm device activation circuit 7 does not operate.

On the other hand, the timer 9 outputs a monotonous operation signal 9', the timer 16 outputs a signal 16' for a period of time T, and the constant frequency oscillation circuit 12 and variable frequency oscillator 14a output signals 12' and 14'a. However, if the driver falls asleep while driving, the driver's control ability is insufficient, so the output 17' of the bandpass filter 17,
17'' does not exceed the set value V ₁ or cannot exceed the set value V ₁ for a predetermined period of time. Therefore, the integral value 19' of the output 18' of the comparator circuit 18 is the set value Since it does not reach V ₂ , AND circuit 2
2 outputs "0", and inverter 23 outputs "1". When the pulse generation circuit 24 outputs the pulse 24' as the set time T elapses, the AND circuit 2
5 outputs a pulse 25', the monostable multivibrator 26 is activated, and the alarm 27 is activated.
Turning off monostable multivibrator 26
The pulse generating circuit 28 outputs a pulse 28', which is output as a reset signal 31' from the OR circuit 11, thereby resetting the timer 9, constant frequency oscillation circuit 12, and variable frequency oscillator 14a.

Furthermore, to explain another example of operation using the time chart in FIG.
outputs signal 10. Since the timer 9 is off (OFF), the inverter 29 outputs the signal 29
The AND circuit 30 outputs the signal 30.
A reset signal 31 is output from the OR circuit 11. Therefore, by outputting the next shift switch signal 8', counting of time t is started again, and when time t has elapsed, timer 9 outputs signal 9'. The timer 16, constant frequency oscillator circuit 12, and variable frequency oscillator 14a output signals 16', 12', and 14'a, respectively, due to the output of the signal 9', but since the driver was drowsy while driving, the driver did not perform any control work. Otherwise, the bandpass filter 17 will not output any signal, so the output of the inverter 23 and the pulse 2 of the pulse generation circuit 24 will be
4', the AND circuit 25 outputs a signal 25'. The monostable multivibrator 26 is activated by the signal 25' to activate the alarm 27, and when the monostable multivibrator 26 is turned OFF, the pulse generating circuit 28 outputs a pulse 28'. The pulse 28' outputs a reset signal 31' via the OR circuit 11, and resets the timer 9, constant frequency oscillation circuit 12, and variable frequency oscillator 14a. During this time, the shift change occurs and the signal 8'
is turned off (OFF), and even if the inverter 10 outputs the signal 10', as long as the reference sound and control sound are emitted, the inverter 29 is turned off (OFF).
Therefore, the alarm will not be reset until the driver completes control work or the alarm stops operating. If there is a shift change again after the alarm 27 is activated, it will be reset by the reset signal 31'', but when the shift switch 8 further outputs the signal 8'', time measurement for time t will start from that time, and after t time, it will be reset. The timer 9 outputs a signal 9''. After the signal 9'' is output, the operation is the same as that shown in FIG. 3, so a repeated explanation will be omitted.

Figure 5 A, B, and C show the characteristics of the bandpass filter 17 explained above, A shows that the frequency of the control sound changes due to the driver's control work, and B shows a certain tolerance range with respect to the reference sound. C indicates that the control sound having a frequency difference of 1 passes through the band pass filter 17 and is output, and
7 shows a signal outputted by the comparator circuit 18 when the output of the circuit 7 exceeds a predetermined set value _V1 .

Figures 6A and 6B show a mechanism for bringing the frequency deviation of the control sound with respect to the reference sound within the permissible range by the driver's control work, and shows the steering wheel 4.
A variable resistor 50 is attached to the spoke 41 of 0. The variable resistor 50 has an operating knob 51 which is given an elastic force by a spring 52, and the operating force of the operating knob 51 (that is, the extent to which the operating knob 51 is pushed in against the elastic force of the spring 52). terminals 53a, 53b, which output three different resistance forces accordingly;
53c, and by connecting three types of resistance values to the control sound generation circuit, control sounds having three types of frequencies can be generated. One of the three frequencies has a difference from that of the reference sound within an acceptable range, and therefore, if the driver is not drowsy at the wheel, the assigned control task can be easily completed within the set time. can do.

As explained above, the drowsy driving detection device according to the present invention detects drowsy driving, which tends to occur during monotonous driving, by imposing control tasks on the driver, so that drowsy driving can be detected accurately. be able to. In the above embodiment, the monotonous driving state is detected by the shift switch, but it is also possible to generate the reference sound and control sound at fixed intervals or fixed distances to have the driver carry out control work. Also,
The warning device is not limited to a warning buzzer, but the warning output can also be used to activate an air conditioner and blow wind on the driver to encourage him to wake up.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention.
FIG. 2 is a circuit diagram corresponding to FIG. 1. 3 and 4 are time charts explaining the operation of the circuit configuration shown in FIG. 2. Figure 5 A, B. C is a characteristic diagram of a bandpass filter. FIGS. 6A and 6B are explanatory diagrams showing a control section for control sound. Explanation of symbols 1... Monotonous operation detection device, 1'... Reset prevention circuit, 1''... Reset circuit, 2... Reference sound generation circuit, 3... Control sound generation circuit, 4, 6... Judgment circuit, 5... Time setting circuit, 7... Alarm device operating circuit, 8... Shift switch, 9... Timer, 12...
Constant frequency oscillator circuit, 14a... variable frequency oscillator, 1
4b... Variable resistor, 16... Timer, 17... Band pass filter, 18... Comparison circuit, 19... Integrating circuit, 21... Comparator, 24, 28... Pulse generation circuit, 26... Monostable multivibrator, 40
...Steering hole, 41...Spoke, 50...
variable resistor.

Claims (1)

[Claims] 1. A reference sound generation circuit that generates a predetermined reference sound when monotonous driving continues for a predetermined period of time, and at least one of the frequency and the intensity of the sound changes under the driver's control. a control sound generation circuit that generates a control sound; and a first sound generating circuit that outputs a control sound when a difference in frequency or amplitude between the control sound controlled by the driver and the reference sound is smaller than a predetermined set value. a determination circuit; a second determination circuit that outputs an output when the output time of the determination circuit exceeds a predetermined time; and a second determination circuit that outputs an output when the output time of the determination circuit exceeds a predetermined time; A drowsy driving determining device comprising: an alarm device activation circuit that outputs an alarm signal when the second determining circuit does not output an output.