JPS6214833A - Apparatus for detecting sleeping - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to a sleep detection device that detects sleepiness caused by sleepiness using brain waves and issues a warning.

Although the inevitable transition into a drowsiness state after feeling drowsy is a very common physiological phenomenon, its often serious consequences cannot be ignored at present. For example, although prevention of sleepy driving is extremely important from the perspective of ensuring safety in automobiles, airplanes, trains, and other modern transportation devices, unfortunately, there is little knowledge of this type of driving in the past. It has not been done. In general, various physiological electrical phenomena are known to be used as a method for detecting the stage in which the human body gradually transitions to sleep. The technique has drawbacks that make it impractical for the above purpose. That is, sleep determination methods using brain waves have been used for a long time in clinical diagnosis by doctors, but the devices are complicated and expensive and are not suitable for the above purpose. Furthermore, according to Japanese Patent Application Laid-Open No. 59-22130, a method has been proposed for measuring the degree of fatigue based on the amount of increase in the integral value of the alpha wave component of brain waves, but alpha waves increase even in a state of stable mental concentration. Therefore, it is not suitable for the purpose of detecting sleepiness while driving.

The object of the present invention is to improve the above-mentioned drawbacks and provide a practical, effective, and portable sleep detection device. The components of brain waves during normal consciousness are generally complex and vary depending on individual differences, environment, physical condition, etc., so brain wave patterns are not necessarily constant, but when one gradually transitions from drowsiness to sleep.

A rapid decrease in amplitude is generally observed with decreasing frequency. The feature of this invention is to obtain a rectified brain wave waveform based on the above facts, process it analog or digitally, and convert the result into a binary signal of 0 or 1, thereby controlling the sleep state. The purpose is to generate a warning signal at the same time as making a determination.

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

Although FIG. 1 shows a detachable attachment part for this invention, it is not necessarily limited to that form (
Any other shape, such as a headphone type, may be used as long as it has the function of detecting brain waves in accordance with the gist of the present invention. FIG. 1 shows a glasses-type device in which brain waves are detected between an electrode 1 that is placed in close contact with the head and a reference electrode 2 that is set on an earlobe, etc., and input to an brain wave signal processing circuit via a lead wire 3. The support rod 4 is connected to the eyeglass arm and serves to bring the electrode 1 into close contact with the head. Figure (2) shows that the tube 5 at the electrode 1
This allows the use of conductive paste. Figures (3) and (4) both show an elastic cloth band type attachment part, and a plurality of electrodes 1 provided on the band 7,
Brain waves from a reference electrode 2 (not shown) are guided to a lead wire 6. Figure (5) is an example of the case where the electrode 1 is attached in Figures (3) and (4), but it is provided in advance on a small piece 8 of cloth or the like, and then attached to the cloth band 7 by an appropriate method. Join.

Next, the brain waves obtained from the attachment part are input to the brain wave signal processing circuit shown in FIGS. 2 and 3.

The operation shown in FIG. 2 will be explained. The brain wave signal amplified by the amplifier 9 passes through a high frequency filter 10 and is rectified into a DC voltage by a rectifying and smoothing circuit 11 in order to remove noise and the like. The rectified electroencephalogram signal voltage passes through a gate circuit 12 and operates an electronic switch 13. Here, if the caulking circuit constants are adjusted in advance so that the normal brain wave signal voltage opens the gate 11, the output of the gate 12 will actuate the electronic switch 13 to stop the warning device 14 (possibly). Next, when you enter a sleep state while driving, etc., the rectified voltage from the brain waves drops due to a sudden drop in frequency and amplitude, so the gate 12 closes and the electronic switch 13 is reversed. A warning device 14 detects overwork and issues a warning.

FIG. 3 shows a method in which the brain wave signal is rectified by the rectifier circuit 15 in the same way as in FIG. 2, but this is converted into digital numbers and arithmetic is performed to detect sleepiness.

Next, the operation will be explained. The rectified signal obtained by the rectifier circuit 15 is converted into a square wave by the pulse conversion circuit 16,
The pulse count is input to the memory 17 as the number of pulses within a certain period of time by the timer 18. The standard value (S) to be compared with (2) can be pre-stored in the memo January 7 using the electroencephalogram signal during normal operation. Arithmetic circuit 19 is S-X or X/S
etc., and the result is converted into a DC voltage by the D/A converter 20 and input to the gate circuit 21. When entering the sleep state, the number of pulses X of the rectified signal from the brain waves decreases corresponding to the decrease in the number of rectified waves and the wave height value, so
The input voltage to the gate 21, which is proportional to -X or X/S, changes and the gate is opened or closed based on this. As the gate is opened and closed, an electronic switch 13 activates a warning device 14 to detect sleep and issue a warning.

In the embodiment of the electroencephalogram signal processing circuit of the present invention, the rectified signal from the electroencephalogram is binary coded into 0 and 1 by the gate circuit 12 or 21, but instead of this, a comparison amplifier (comparator) is used. May be used. In addition, this binary code can be used not only to be input to the electronic switch 13, but also to be used for portable engine control purposes, such as when detecting sleep for automatic or other purposes, as well as analog or digital input. By converting the processed electroencephalogram signal into an O or 1 signal, the state of sleepiness can be determined very clearly, which is effective in preventing sleepiness.

[Brief explanation of the drawing]

FIG. 1 (1) is a structural diagram of a glasses-type wearing part for electroencephalogram detection according to the first embodiment of the present invention, (2) is a structural diagram of an electrode of the glasses-shaped wearing part using conductive paste, and (3) is the second part of the mounting part.
A structural diagram of the band type of the embodiment, (4) is a structural diagram of another band type of the third embodiment of the attachment part, (5) is a structural diagram of the electrode attached to the cloth band, and Fig. 2 is an electroencephalogram signal processing diagram. A block diagram of the first embodiment of the circuit is shown, and FIG. 3 is a block diagram of the second embodiment. 1... Electrode 2... Reference electrode 3 and 6... Lead wire 4... Support rod 5... Tube 7... Cloth band Death... Piece of cloth 9... Magnifier 10. ...High frequency filter 11... Rectification and smoothing circuit 12 and 21...
- Gate circuit 13... Electronic switch 14... Warning device 15... Rectifier circuit 16... Pulse conversion circuit 17... Memory 18... Timer 19... Arithmetic circuit 20... D/ A converter Note that the same reference numerals in the drawings indicate the same or equivalent parts.

Claims (6)

[Claims] (1) A sleep detection device comprising a removable attachment part having an electroencephalogram electrode and a conduction part, and an electroencephalogram signal processing circuit for detecting sleep. (2) The above-mentioned brain wave signal processing circuit processes the rectified signal from the brain wave in an analog or digital manner and outputs 0 or 1
2. The sleep detection device according to claim 1, wherein sleep detection is performed by converting the sleep state into a binary signal. (3) The sleep detection device according to claim 1 or 2, wherein the brain wave signal processing circuit is equipped with a warning device using sound, light, or the like. (4) The sleep detection device according to claim 1, which is portable. (5) A sleep detection device for a driver or an operator according to claim 1. (6) The sleep detection device according to claim 1 or 2, which is used for controlling an automobile engine.