JPS6076424A - Dozing at wheel detecting device - Google Patents

Abstract

PURPOSE:To prevent the erroneous detection of dozing at wheel based on a steering signal and improve detecting accuracy by providing a pulse interval detecting means which clears an integrated value of rotating signals by a steering signal forming means. CONSTITUTION:A steering detecting means 1 detects that a steering wheel made a rotation by a certain angle and outputs a rotation signal. A steering signal forming means 3 integrates the outputted rotation signals and, on detecting that a certain value is reached, it outputs a steering signal. Occurrence of dozing at wheel is detected based on the outputted steering signal, and a warning is issued by a dozing at wheel detecting means 5. A pulse-interval detecting means 7, which outputs a clear signal to the steering signal forming means 3, when it detected that the time for the input interval of the rotating signal is above a certain time, to clear the integrated value of the rotating signals by the steering signal forming means 3, is provided.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a device that detects the rotation of a steering wheel and detects the occurrence of drowsy driving based on the detection result. Regarding a detection device.

[Technical background of the invention and its problems] Drowsy driving detection devices that attempt to detect the occurrence of drowsy driving from detection results such as the steering angle and steering frequency of the steering wheel have been proposed (for example, Japanese Patent Publication No. 1983 -42488, JP-A No. 51-25228). These devices determine whether or not the number of signals output each time the steering wheel is relatively rotated by a predetermined angle (for example, 3 degrees) exceeds a preset threshold. The occurrence of drowsy driving is detected based on the results of judgments such as whether or not a signal has not been output for a certain period of time (no-steering condition).

As this type of drowsy driving detection device, the inventor of the present application has filed an application (Japanese Patent Application No. 57-18761) with the content described below.
No. 2), and the conventional example of the present application will be described below based on the present invention. In other words, the steering is controlled by the rotation signal (see Fig. 1 (B), hereinafter referred to as "1" pulse) that is output every time the steering wheel is rotated by 1 degree (see Fig. 1 (A>)). Means (not shown) is provided for generating a steering signal (see FIG. 1C, hereinafter referred to as a "3° pulse") indicating that the wheel has been rotated 36 consecutive times in the same direction. If it detects that there is no output for the 3° pulse for a certain period of time To (for example, 1 second) or more, it is determined that there is a suspicion of drowsy driving (no-steering condition), and the steering wheel is turned in the same direction after that. The output by steering to (first steering) is a predetermined value (for example, 5
pulse), and the output due to the subsequent steering in the opposite direction (second steering) is a predetermined value (for example, 4 pulses)
When the above condition occurs within a certain time T1, it is determined that drowsy driving has occurred (in the example of FIG. 1, it is not drowsy driving).

This drowsy driving detection method based on the steering angle of the steering wheel, the steering frequency, etc. can provide a drowsy driving detection device that can perform accurate detection. By the way, in the above-mentioned apparatus, a 3° pulse is simply generated when three 1° pulses are outputted by steering the steering wheel in the same direction. However, in such a method of forming a 3° pulse, for example, in the signal states (A) to (C) of Fig. 2, the steering wheel is rotated within a certain time T1 after the occurrence of a no-steering condition, as in the case of Fig. 1. When attempting to detect a sudden turn-turn steering, the detection of the turn-back steering should normally start from the 1° pulse indicated by the reference symbol P in Fig. 2 (B), but if the turn-over steering is in a no-steer state, Detection starts from the 1° pulse indicated by the reference symbol PI, which is not appropriate as 3° pulse data for determining drowsy driving, and may cause errors in the judgment result. This problem occurs because the previously outputted 1° pulse was also targeted for formation of 36 pulses.

[Objective and Summary of the Invention] The present invention has been made in view of the above, and an object thereof is to provide a drowsy driving detection device that improves detection accuracy by obtaining an appropriate data signal for drowsy driving detection. The offer is to cover.

In order to achieve the above object, the present invention detects that the steering wheel has rotated by a certain angle and integrates the rotation signal output from the steering detection means 1 to a predetermined value, as shown in Fig. 33. In the drowsy driving detecting device, the drowsy driving detecting device has a drowsy driving detecting means 5 which detects the occurrence of drowsy driving based on the steering signal outputted from the steering signal forming means 3 upon detecting that the turning signal has reached the position of the turning signal. When it is detected that the input interval time exceeds a predetermined time, a clear signal is output to the steering signal forming means 3, and the steering signal forming means 3 outputs a clear signal to the steering signal forming means 3.
The gist is that a pulse interval detection means 7 is provided to clear the integrated value of the rotation signal.

[Embodiments of the invention] Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 4 shows an embodiment of the present invention.

In the figure, 9 indicates that the steering wheel is at a certain angle (for example, 1
°) A steering angle sensor that outputs a rotation signal (1° pulse) every time it rotates, 11 inputs and processes the 16 pulses,
When drowsy driving is detected, a lamp, buzzer,
This is a microcomputer that issues an alarm via alarm means 134- such as audio.

Note that the microcomputer 11 includes a CPU 15, an RO
The configuration includes an M17, a RAM 19, and an input/output board 21.

As the steering angle sensor 9, for example, the patent application filed in 1982 by our company
The configurations shown in FIGS. 1 and 2 (a) and (b) of No. 187612 are conceivable.

Next, the operation of this embodiment will be explained based on the processing flowchart of the CPIJ15 shown in FIG.

First, when a predetermined precondition for starting drowsy driving detection such as whether the vehicle speed exceeds a predetermined speed is established (step 30), a 1° pulse is input and the 1° pulse After determining whether the steering is caused by steering to the left or left steering (step 40), the content of the counter register UDC is incremented until the content reaches a predetermined value (for example, 3).
), outputs a steering signal ("3° pulse") (
Step 50). Then, calculations are performed based on the 36 pulses to determine whether or not drowsy driving has occurred (steps 60 and 70), and if drowsy driving has occurred, a warning is issued (step 80).

The details of the process in step 40 are as shown in FIG. 7 of Japanese Patent Application No. 187612/1987 filed by our company, for example.

The details of the process in step 50 are as shown in FIG. When 16 pulses are input, the previously input 1°
Determine the input interval time Δt with the pulse, and if t exceeds a predetermined time (for example, 1 second), the contents of the counter register U[)C, the left pulse register 1- and the right pulse register R, which will be described later, are After clearing step 140
(Steps 100-130). That is, the 16 pulses that were input before the input interval time Δt exceeded 1 second are not used in the formation of the 3° pulse described below. Note that if the input 1° pulse is the first one, the process advances to step 140 via step 120.

In step 140, if the input 16 pulses are due to steering to the left, the process proceeds to step 150; on the other hand, if the input 16 pulses are due to steering to the right, step 210 is performed.
Proceed to step 1 to form a 13° pulse.

Proceeding to step 150, the counter register UDC
left pulse register L whose value indicates the maximum continuous leftward steering angle of the steering wheel.
If the contents exceed the contents of the register L, the contents of the register L are updated to the contents of the counter register UDC, and then the process proceeds to step 180 (steps 150 to 170>). Therefore, 220.23 changes were detected.
Store the minimum value in steps of 0. Step 180
When proceeding to , it is determined whether or not the steering wheel has been continuously steered 3 degrees to the left, and when it reaches 30, a 3 degree pulse is output, and the counter register UDC, left pulse register L, and right pulse register R are Clear the contents (steps 180-200). Note that step 180
If the condition is not satisfied, the process returns to step 100 and enters the input timing state for the next 1° pulse.

On the other hand, when the process proceeds to step 210, the contents of the counter register UDC are decremented, and when the value becomes equal to or less than the contents of the right pulse register R indicating the minimum continuous rightward steering angle of the steering wheel, the contents of the register R are decremented. After updating the contents of counter register UDC, step 24
0 (steps 210-230). Step 240
, it is determined whether or not the steering wheel has been continuously steered to the right by 3°, and when it reaches 3°, a 3° pulse is output, and the counter register UDC, the left pulse register, and the right pulse register R are output. Clear the contents of (steps 240 to 250.200). Note that if the condition is not satisfied in step 240, step 100
The state returns to the input timing state for the next 1° pulse.

The details of the process at step 60 in FIG. 5 are as shown in FIG. When the 3° pulse formed in steps 100 to 250 described above is manually generated, the state of the no-steering flag MSF indicating the occurrence of a no-steering state is determined, and if it is set, sudden steering is determined. The process proceeds to step 540, and if the reset state is present, the process proceeds to step 520 to determine whether or not no steering occurs (step 5
00-510).

Proceeding to step 520, it is determined whether the input interval time with the previously input 3° pulse exceeds a predetermined time To (for example, 1 second), and if not, step 5
If it exceeds 00, it is determined that a no-steering condition has occurred, and the no-steering flag MSF is set, and then the process returns to step 500. In either case, the next 3° pulse input timing condition is determined. (Steps 520-530).

On the other hand, when the process proceeds to step 540, there is a suspicion that a no-steering condition has already occurred and drowsy driving has occurred, so in the subsequent processing, it is determined whether or not sudden steering (first steering and second steering) has occurred, and drowsy driving is suspected. To determine whether or not the occurrence has occurred, first, it is determined based on the state of the first steering flag F1 whether or not the first steering has already been performed, and if it is set, that is, if the first steering has already been performed. The process proceeds to step 590 to determine whether the second steering has occurred, and if it is in the reset state, the process proceeds to step 550 to determine whether the first steering has occurred.

Proceeding to step 550, it is determined whether the input of 3° pulses due to steering in the same direction exceeds a predetermined value (for example, 4) within a predetermined time (for example, 1 second). As a result, if the determination condition is met, it is determined that the first steering has occurred, the first steering flag F1 is set, and the process returns to step 500, whereas if the condition is not met, the process proceeds to step 570 and input is made. If the 3° pulse is due to steering in the opposite direction to the previously input 3° pulse, it is determined that the suspicion of drowsy driving is cleared, the no-steering flag MSF is cleared, and the process returns to step 500 (step 560 to 580) When the process proceeds to step 590, the input of 36 pulses formed by steering in the opposite direction to the 3° pulse that established the first steering reaches a predetermined value (for example, 4 ) is exceeded. As a result, when the determination condition is satisfied, it is determined whether or not the condition is satisfied within a predetermined time (for example, 1 second) after the first steering flag F1 is set (step 600), and if it is within the predetermined time, drowsy driving is detected. It is determined that this has occurred, and the process proceeds to step 70 to issue an alarm.
Conversely, if the predetermined time has been exceeded, it is determined that no drowsy driving has occurred, and after clearing the no-steering flag MSF and the first steering flag F1, the process returns to step 500 (step 6
20). On the other hand, if the determination condition is not satisfied, the process proceeds to step 610, and the input 3° pulse is the same as the previously input 3° pulse.
If the steering wheel is turned in the opposite direction to the pulse, it is determined that the suspicion of drowsy driving has been cleared, the no-steering flag MSF and the first steering flag F1 are cleared, and the process returns to step 500 (steps 610 to 62).
0).

The processing method of step 60 is, for example, as described in Japanese Patent Application No. 57-149218 and Japanese Patent Application No. 58-248 filed by our company.
The method described in No. 50 or the like may also be used.

11- Therefore, according to this embodiment, even in the steering situation shown in FIG. 2, the judgment of sudden steering is made from the 1° pulse indicated by reference symbol P, and it is possible to accurately judge whether or not there is sudden steering.

[Effects of the Invention] As explained above, according to the present invention, the steering signal is generated based on the steering signal that is formed and output when the integrated value of the rotation signal that is output when the steering wheel rotates by a certain angle reaches a predetermined value. In the device for detecting the occurrence of drowsy driving, when the input interval time of the rotation signal exceeds a predetermined time, the integrated value is cleared and a steering signal is generated depending on the rotation signal output before the predetermined time. Therefore, it is possible to prevent erroneous detection of drowsy driving based on the steering signal and improve detection accuracy.

[Brief explanation of drawings]

1 and 2 are side views of the signal status of 1° pulse and 3° pulse accompanying steering operation, FIG. 3 is a diagram corresponding to claims, and FIG. 4 is a block diagram showing an embodiment of the present invention. 5 to 7 are operation flowcharts of FIG. 12-FIG. 4. (Explanation of symbols representing main parts in the figure) 1...Steering detection means 3...Steering signal forming means 5...Drowsy driving detection means 7...Pulse interval detection means 111← Figure 2

Claims (1)

[Claims] Steering detection means that outputs a rotation signal every time the steering wheel rotates by a certain angle; and a steering device that detects that the cumulative value of the rotation signal reaches a predetermined value, clears the cumulative value, and outputs a steering signal. a signal forming means; a pulse interval detecting means for clearing the integrated value when it is detected that the output interval time of the rotation signal exceeds a predetermined time; and a pulse interval detecting means for calculating the steering signal to detect occurrence of drowsy driving. 1. A drowsy driving detection device, comprising a drowsy driving detection means that issues an alarm when the vehicle is drowsy.