NL1021496C2 - Monitoring device for alertness of person, especially vehicle driver, generates warning signal if eye is detected as being closed too long - Google Patents

Abstract

A means is provided for recording the open or closed position of one or both eyes (9) and when an eye is detected as being closed a timer is started and if the time that the eye remains shut exceeds a pre-determined limit a warning signal is generated by a signalling device (13).

Description

Title: Signaling device and method for monitoring the alertness of people

The invention relates to a signaling device. The invention relates in particular to a signaling device for monitoring alertness of persons such as drivers of vehicles, operators of machines and the like.

5 When operating devices and machines such as vehicles and the like, it is of great importance that users are sufficiently alert. Declining attention and falling asleep must be prevented at all times. This can prevent errors and accidents and also improve user performance.

The object of the invention is to provide a device of the type described in the preamble, in which the alertness of a user can be viewed in a simple and non-invasive manner and a signal can be given when the alertness decreases. To that end, a signaling device according to the invention is characterized by the features of claim 1.

A signaling device according to the invention is adapted to register an open or closed position of at least one eye, at least for movement of an eyelid of at least one eye. This registration preferably takes place remotely, i.e. there is no physical contact between the device and the eye in question, at least eyelid. When it is found that the eye in question remains closed for an undesirably long time, which can be checked with the aid of a timer, a signal is issued that the relevant user whose eye is being observed or can warn his surroundings. The necessary measures can then be taken, for example termination of a task, taking over of a task or the like. As a result, accidents and damage can be prevented in a particularly simple, economic, safe and pleasant way.

? r \ 'Λ r' \ .0 * - ^ a 2

In a first advantageous embodiment, a signaling device according to the invention is characterized by the features of claim 2.

In such an embodiment, use is made of a light source and a light sensor. During use, a light beam is emitted continuously or intermittently by the light source, which light beam is intended to be captured by the light sensor, reflected by a relevant eye, in particular eye white. If the eyelid is closed, the light beam will not be reflected, at least insufficiently or in the wrong direction, as a result of which the light sensor will not or insufficiently perceive it. The timer is then started, which is again stopped or reset when the eyelid is opened again, so that the light beam is reflected again by the eye, in particular the whites of the eyes, and is sufficiently absorbed by the light sensor. If an eyelid 15 remains closed for a long time (undesirably long time), the timer will exceed a predetermined time and the desired signal is emitted. This signal can be, for example, acoustic, optical or tactile.

It is preferred that a light-emitting diode (LED) or similar low-power light source is used as the light source, which light emits light that is harmless to an eye, also over relatively long periods. As a light sensor, for example, a solid state light sensor, such as an optical cell, can be used, wherein light source and light sensor function as opto-coupler.

In an alternative embodiment, a signaling device according to the invention is characterized by the features of claim 5.

In such an embodiment, distance measurement or distance difference measurement determines whether the eye is closed or open, on the basis of which an alarm signal can be given if the eye remains closed for longer than desired.

3

In this embodiment use is made of a camera and image recognition means for registering an opened and / or closed position or eye movements, at least eyelid movements. Again, a closed eyelid will lead to the timer starting, reopening the eyelid until stopping or resetting the timer. Keeping the eye closed too long, or at least eyelid, then again leads to the said signal. The camera and recognition means can of course also be used for determining the position of, for example, an eye relative to a desired, reference position. Long-term, relatively large deviations between said positions will then lead to the said signal. The preselected time for the timer is preferably adjustable.

In an advantageous embodiment, a signaling device is further characterized by the features of claim 8.

In such an embodiment, at least the recording means can be placed on or near a head of a user, so that the operation thereof is not influenced by movement of said head. At least the registration means will move with the head. Attachment to an ear offers the advantage that the recording means can be positioned relatively easily near an eye corner, without a user being disadvantaged by this.

In a further alternative embodiment, a device according to the invention is characterized by the features of claim 12.

With such a signaling device movements of the head can be recognized, at least positions thereof and compared with a desired reference position, wherein too large and / or too long deviations from said reference position will lead to the aforementioned signal. Parts of the head can also be viewed for this purpose, for example eyes, an ear or the like.

/! n

Ulv T UlUiilg 11VV1V TW1VO WVViAAllg V ^ / VVA1 VV for VUA ^ AU ^ UMUMMVAUg for use in a vehicle, characterized by the features of claim 15.

Such a safety device offers the advantage that a user, in particular a driver of the relevant vehicle, can be warned in time when his or her alertness drops below a desired level, for example because he or she falls asleep.

The invention further relates to a vehicle provided with a security device or signaling device according to the invention.

The invention furthermore relates to a method for registering a person's alertness, characterized by the measures according to claim 17.

With such a method it is relatively easy to determine whether a particular person is sufficiently alert to perform a specific task, for example driving a vehicle, operating machines or the like. If that alertness is or becomes too low, a signal will be issued so that appropriate measures can be taken.

The invention further relates to the use of pattern recognition means for registering decreasing alertness of a person, characterized by the measures in claim 20.

Further advantageous embodiments of the invention are given in the further subclaims. To clarify the invention, exemplary embodiments of a signaling device, security device, method and use will be described with reference to the drawing. It shows:

Figure 1 shows diagrammatically a signaling device according to the invention with an opened eye; Figure 2 shows the signaling device according to Figure 1, with the eye closed; Figure 3 shows a first alternative embodiment of a signaling device according to the invention; figure 4 shows diagrammatically in perspective a signaling device according to the invention with positioning means for positioning behind an ear; Fig. 5 is a plan view of glasses provided with recording means according to the invention; Figure 6 shows a cap with recording means according to the invention; and figure 7 shows diagrammatically in side view a driver's position of a vehicle, in particular a car with a security device according to the invention.

In this description, the same or corresponding parts have the same or corresponding reference numerals.

Figure 1 shows schematically a signaling device 1 according to the invention, positioned near an eye. In this embodiment the signaling device 1 comprises a support arm 2 which comprises a light source 4 and an adjacent light sensor 5 near a first end 3. The light source 4 is, for example, a red light-emitting diode (LED), the light sensor 5, for example, a photoelectric cell. A connecting wire 6 runs through or along the carrying arm 2, with which the light source 4 and the light sensor 5 are coupled to a control unit 7. At least the light source 4 and the light sensor 5 are supplied via the control unit 7. In the control unit 7 a timer is included which can be switched on and off with the aid of a control signal originating from at least the light sensor 5, as will be further discussed. The light source 4 and the light sensor 5 are attached to a head by means of the carrying arm 2 and further positioning means (not shown in Figs. 1-3) such that the light source 4 and the light sensor 5 are located at a relatively small distance from an eye corner 8 of an eye 9 are placed. For simplification, Figs. 1-3 always show the eye 9 and the carrying arm 2 with the light source 4 and light sensor 5 in one plane.

- * -: 6

In practice, however, the carrying arm 2 will, for example, extend along the head from an ear to near said eye angle 8, wherein the light source 4 and the light sensor 5 are positioned such that through the light source 4 a light beam 10 is approximately horizontal, at least approximately perpendicular to the eye 9 is directed near said eye angle and can be reflected therefor such that with the eye open, as shown in Figure 1, the light beam 10 reflected by the eye white 11 of the relevant eye angle 8 can be reflected and can be reflected by the light sensor 5 captured. We will come back to this goal in more detail.

A control device 12 is coupled to the control unit 7 and is connected to a signal source 13, for example a loudspeaker with a tone generator. With the setting means 12 a preselected time can be set for the timer in the control unit 7, for example between a few tenths of a second and a few seconds.

In figure 2 the signaling device 2 according to figure 1 is shown again, in the same position, however, the eye 9 is closed by the eyelid 14. A light beam 10 emitted by the light source 4 is not reflected, or at least insufficiently focused, by the eyelid 14, but is spread, as indicated by the arrows 15. Through the light sensor 5, the light beam 10 is not observed, at least to a sufficient extent. Thus, with the aid of the light source 4 and the light sensor 5, it can be determined whether the eye 9 is open, as shown in Figure 1, or closed, as shown in Figure 2. A signaling device 1 according to Figures 1 and 2 can be used as follows .

The signaling device 1 is placed as previously described, attached to a head, after which the timer of the control unit 7 is reset to zero and the light source 4 is switched on. As long as the eye 9 is open, the light beam 10 detects the light beam 10, which can be transmitted continuously or intermittently. A signal is supplied by the light sensor 30 to the control unit 7, whereby the timer is kept at zero. When the eyelid 14 is closed, as shown in Fig. 2, the light beam 10 is made by the light sensor 5. is no longer detected and a signal is sent by the light sensor 5 to the timer, which is started as a result: As long as the eyelid 14 remains closed, the timer 5 continues to run if the time recorded by the timer (the time that the eyelid 14 remains closed continuously) ) exceeds the time set with the aid of the adjusting means 12, the signal source 13 is controlled by the control unit 7, as a result of which an alarm signal will sound, symbolically represented by the lines 16. However, the eyelid 14 is lifted before the time recorded by the timer exceeds a preset time, so that the light beam 10 is again reflected by the white of the eye 11 and is caught by the light sensor 5, then the timer becomes Unit 7 is again reset to zero and no alarm signal 16 will be issued. This means that, for example, blinking of the eyelids 15 may be registered by the signaling device 1, but that this will not cause an alarm signal 16 to be issued. However, if the eyelids 14 remain closed for a relatively long time, for example a few tenths of a second or more, the signaling device 1 will recognize this in the above-mentioned manner and will give an alarm signal in order to alert the user and / or his environment, or at least to continue to indicate that it is closed. This allows accidents and errors to be avoided. When the signaling device 1 is placed, it will be easy to adjust. After all, if the light source is not directed correctly, it will give an alarm signal almost immediately. Only when the light source, or at least the signaling device 1, is set correctly, will there not be an alarm signal 16, unless the eyelid 14 remains closed for too long.

In an alternative embodiment, which is similar in structure to that shown in Figs. 1 and 2, wherein, however, a different light source 4 and light sensor 5 are applied, at least the signals obtained therewith are interpreted differently. In this embodiment, the light source 4 is 1 Π '' + -j h

WU UV XXV / XJ. 1 / UVilljUl u MAVgVTVVlU fiUUCUUg UUU UUUAUAW UV UAOVUAAVI VUV AlV V

eye white 11, at least the eyeball, as shown in figure 1 and / or up to the eyelid 14, as shown in figure 2 can be measured. From this distance or distances and / or from the difference between them, the control unit 7 can determine whether the eye is open or closed. As soon as the eye is closed, during use, the timer is set again as described above and an alarm signal is given if a limit is exceeded.

Figure 3 shows a further alternative embodiment of a signaling device 1 according to the invention, again provided with a carrying arm 2, which in this embodiment, however, is provided near the first end 3 with a camera 20 as a recording means, which camera 20 is aimed at the eye 9. The camera 20 is connected via the connecting wire 6 to pattern recognition means 21, coupled to the control unit 7, which again comprises a timer. The control unit 7 is connected to a signal source 13, in this embodiment for example a vibrator which can be placed against a body part with a vibrating arm 13A. Of course, other signal sources can also be used in each of the embodiments according to the invention, also in combined form. Setting means 12 are again connected to the control unit 7 for setting at least the preselected time. The pattern recognition means 21 are arranged for comparing an image of the eye 9 that is currently recorded with the camera 20 and an image of an (opened) eye that has been previously entered as a reference, for example by displaying an image immediately after placing the signaling device 1 with the camera 20 25 of an opened eye 9 in the pattern recognition means 21 and to record it as a reference image. During use, images of the eye 9 are taken continuously or periodically with the camera 20 and compared with said reference image. If this deviates undesirably, for example because the eyelid 14 is completely or largely closed, so that, for example, the pupil 9A of the eye 9 is no longer visible, the timer is started. As soon as the eye 9 is again sufficiently open and an image thereof again sufficiently matches the reference image, the timer is stopped. However, if the deviation of the reference image lasts longer than the preset time, the timer will exceed said time and the signal source 13 will be driven to alert the user and / or his environment. The camera 20 can be designed in any suitable manner, for example as a digital camera, as a DCC camera, as an analog camera or the like. In principle, it is sufficient that only a portion of the eye 9 is viewed with the camera 20, for example, whites of the eyes in an eye corner, the pupil 9A or another part. The camera 20 can also be set such that movements of the eyelid 14 and / or the eye 9 are recorded and compared with a reference pattern of movement recorded in the pattern recognition means 21. Using a camera 20 has the advantage that the camera does not emit radiation on the eye 15. An embodiment according to figures 1 and 2, however, has the advantage that this embodiment is relatively simple.

Figure 4 shows diagrammatically in perspective view a signaling device 1 according to the invention, in particular according to figure 3, wherein positioning means are provided in the form of an ear clip 22 which is known per se and which are provided with a second end 23 of the carrying arm 2. connected. A camera 20 is again attached to the first end 3 of the carrying arm 2. The ear clip 22 can be clamped around an ear, a connecting wire 6 extending from near a free end of the ear clip 22 and connected to the control unit 7, symbolically represented by a cube. Connected to the control unit 7 is a loudspeaker 13 as a signal source and a lighter plug 24 through which the recording device 1 can be supplied via a cigarette lighter socket of a vehicle. Of course, other means for feeding are also possible, for example batteries or direct coupling to a battery. The carrying arm 2 is preferably somewhat deformable, such that the camera 20 can always be positioned properly. It will be clear that a device 1 according to figures 1 and 2 can be designed in the same or comparable manner.

Fig. 5 shows alternative positioning means, in the form of glasses 25. The glasses 25 are shown in plan view and has two springs 26 and two glasses 27 accommodated in a frame 28. The frame 28 is connected in hinges 29 to the springs 26 such that the glasses 25 can be folded. Near one of the hinges 29 a light source 4 is placed on the frame 28, next to a light sensor 5. The light source 4 and light sensor 10 are similar to those shown in figures 1 and 2. A connecting wire 6 extends from the light source 4 and light sensor 5 from, along or through the spring 26 to the free end 30 of the relevant spring, from where the connecting cord 6 extends to the control unit 7 (not shown). The operation of this embodiment is the same, or at least comparable to that shown in Figs. 1 and 2. Of course, a camera 20 can be worn in the same manner.

Figure 6 shows a further alternative embodiment of a signaling device 1 according to the invention, in the form of a head cover, in particular a cap 31 with valve 32, wherein near one of the corners of the valve 32 a carrying arm 2 is provided on which a camera 20 is worn. The camera 20 can be connected with a connecting cord 6 to a control unit 7 (not shown). Of course, a headgear can also be designed differently, for example as a sun visor, hat or the like. Cameras can also be provided on either side, while in a similar manner a head cover can be provided with a light source 4 and light sensor 5.

It will be clear that the light source 4 and the light sensor 5 can also be of different design, for example a low-power laser as a light source, while the light source 4 and light sensor 5 can also be accommodated in one housing 30. Instead of the positions of the camera 11 shown, it is also possible to opt for, for example, a fiber optic wire which is placed with a free end near, for example, an eye angle, wherein the recorded image is passed on to a camera placed near the opposite sides. This means that the volume of the device 5 near the eye corner 8 is even smaller and will therefore hinder the user even less.

Figure 7 shows a further alternative embodiment of a signaling device 1 according to the invention, in a vehicle 40.

In this embodiment, the vehicle 40 is a car and the signaling device 1 is positioned near the driver's seat. Figure 7 shows schematically in side view a seat 41, a dashboard 42 with handlebar 43, a windshield 44 and a roof 45. Near the transition between the windshield 44 and the roof 45 a first camera 20 is placed, directed at a position where during normal use the head 46 of a driver (shown schematically by a circle). A second camera 20 is placed on the dashboard 42, also aimed at the driver. One camera may also suffice or even more cameras may be provided. Multiple cameras offer the advantage that at least one camera can always view the desired image. The or each camera 20 is connected to a control unit 7 which is provided with a signal source 13 in the form of a loudspeaker. Moreover, a vibrating mat 47 is placed on the seat 41, for example in the transition between the seat 48 and the backrest 49. Pattern recognition means 21 are coupled to the control unit 7. A signaling device 1 in this embodiment can be as follows are used.

A driver takes a seat on the seat 41, such that the or each camera 20 is directed at his or her head 46. Optionally, the or each camera can be mounted for this purpose on a movable support, which can for instance be coupled to memory means of an electrically adjustable chair, such that each time the user adjusts the chair in a (preferred) position, the or each camera 20 automatically is directed at his or her head 46. Subsequently, with the aid of at least one camera 20, a reference image is recorded in the pattern recognition means 21. Subsequently, 5 images are taken from the driver's head 46 with the or each camera 20, which images are compared with the reference image. In the event of deviation from the reference image, a timer is again started in the control unit 7. If the timer exceeds a preset time because the head 46 is not returned to the desired position sufficiently quickly, the signal source 13 is controlled by means of the control unit 7 for issuing an alarm signal and / or the vibrator 47 is controlled for the tactile warn the driver. If the head 46 is returned in time to or near the reference position, the timer is stopped and reset and a new cycle begins.

The invention is by no means limited to the exemplary embodiments shown in the description and the drawings. Many variations thereof are possible within the scope of the invention as set forth in the claims.

For example, the recording means such as cameras, light sources and light sensors shown in the different exemplary embodiments can be combined with the different positioning means shown and described, pattern recognition means and used in, for example, vehicles such as cars, buses, trucks and the like. But also, for example, for persons who perform management or monitoring functions and suchlike. All kinds of other positioning means can be used for attaching a signaling device according to the invention, for example for attaching to clothing or to artifacts in the environment of a user. The recording means can also be arranged at other positions, for example directed at a center of an eye. Furthermore, other light sources and / or light sensors can be applied, while other radiation sources and associated receivers 13 can also be used as long as they can be reflected by an eye, whereby a distinction can be observed between the position and the position of reflection between a position at which an eyelid of the eye in question has been opened and that with which the eyelid is closed. The time between the detection of the undesired position of the eye, head or the like and the issuing of an alarm signal is preferably adjustable as indicated, but may also be recorded in the control unit. Pattern recognition means for use within the invention can be individualisable, whereby a reference image is always fixed again, but can also be provided with a relatively fixed reference image, for example an image of an average eye white or be set to an average blinking frequency of eyelids. Of course, the recording means can also be wirelessly connected to the control means.

These and many comparable variations are understood to fall within the scope of the invention as set forth in the claims.

i; i y Ί 7 - Mo

Claims (20)

A signaling device, provided with recording means for registering an open or closed position of at least one eye, signaling means and a timer, wherein during use it is registered with the aid of the recording means whether an eye is closed and when the eye is closed the timer is started, after which a signal is issued by the signaling means when a predetermined time is exceeded by the timer. 2. A signaling device as claimed in claim 1, wherein the signaling means comprise a light source and a light sensor, wherein during use the light source is directed at an eye, such that when the eye is open the light is reflected and captured by the light sensor, the timer being captured started when the light sensor does not capture the light from the light source and stops it, at least is reset when light from the light source is again captured by the light sensor 15. Signaling device according to claim 2, wherein the light source comprises a light-emitting diode (LED), preferably for substantially monochrome light. The signaling device according to claim 2, wherein the light source 20 is a low power laser. 5. A signaling device as claimed in claim 1, wherein the signaling means comprise a light source and a light sensor, wherein during use the light source is directed at an eye and the distance is measured from the eyeball with the eyelid open and / or from the eyelid with the eyelid closed, wherein change of said measured distance, said timer is started or stopped. The signaling device according to claim 1, wherein the recording means comprise a camera coupled to image recognition means. 7. A signaling device according to claim 6, wherein the image recognition means are adapted to recognize an opened and / or a closed eye or a movement of an eyelid. 8. A signaling device according to any one of the preceding claims, wherein the timer, at least the preselected time, is adjustable. 9. A signaling device according to any one of the preceding claims, wherein positioning means are provided for positioning the signaling device on or near a user's head. 10. A signaling device according to claim 9, wherein the positioning means comprise fixing means for fixing to an ear. 11. A signaling device according to any one of the preceding claims, wherein positioning means are provided for placing at least a part of the signaling device in a vehicle. 12. A signaling device according to any one of the preceding claims, wherein the recording means comprise a camera, coupled to pattern recognition means for recognizing the position of at least a part of a head, which pattern recognition means are adapted for comparing the position of a head with a preset desired position of the head, wherein in the event of a deviation from the position of the head from the desired position of the head the timer is started and when a predetermined time is exceeded the timer assumes that the eyes of the head concerned are closed and a signal is output from the signaling means. A signaling device according to claim 12, wherein the pattern recognition means are adapted to recognize at least the position and / or the position of at least one of the eyes of the head as an indication of the position of the head. 14. A signaling device according to claim 12, wherein the pattern recognition means are adapted to recognize at least the position and / or the position of at least one of the ears of the head as an indication of the position of the head. 15. Security device for use in a vehicle for registering decreasing alertness of a driver, comprising a signaling device according to any one of the preceding claims, wherein the signaling means are adapted to alert the driver when the alertness has decreased, in particular when falling asleep . A vehicle provided with a security device according to claim 14 or a signaling device according to one of claims 1 to 14. 17. Method for registering a person's alertness, wherein the position and / or functioning of at least a part of the body of the driver is recorded, wherein in the event of deviation from that position and / or the functioning of the part in question a signal from a desired position and / or functioning during a predetermined time is issued. The method of claim 17, wherein the position and / or functioning of at least one eye or eyelid is recorded. The method of claim 17, wherein the position of at least a portion of the head is recorded. 20. Use of pattern recognition means for recording decreasing alertness of a person, in particular of a driver or passenger of a vehicle. "" P