JP7624853B2 - Vehicle driver condition determination device - Google Patents

Description

The present invention relates to a vehicle driver state determination device.

Devices for determining the driver's state of a vehicle have been proposed (see, for example, Patent Documents 1 to 5).

The above-mentioned Patent Document 1 discloses an information processing device that estimates a user's state based on biological information such as pupil diameter obtained from the user. The above-mentioned Patent Document 1 describes that a reference pupil diameter (reference pupil diameter) is calibrated based on measurement conditions such as the amount of ambient incident light or the gaze point for measuring the user's pupil diameter, and the user's state is estimated by setting an appropriate reference pupil diameter for the measurement conditions. The above-mentioned Patent Document 1 also describes that if the measured pupil diameter is larger than the reference pupil diameter, it can be estimated that the user is in an excited state, and if the measured pupil diameter is smaller than the reference pupil diameter, it can be estimated that the user is in a fatigued (sleepy) state.

Patent Document 2 discloses a visibility support device for a vehicle that ensures an appropriate visibility for the driver when driving at night, etc. Patent Document 2 describes that the face of the driver of the vehicle is captured by an imaging device, the driver's pupil diameter is obtained from the captured image, and the headlight illumination range is determined based on the driver's pupil diameter by referring to an illumination range map that specifies the relationship between the pupil diameter and the headlight illumination range.

Patent Document 3 discloses a driver state determination device that uses a lighting unit (e.g., blinking of a turn signal lamp) installed in the vehicle to determine the state of the driver based on changes in the diameter of the driver's pupils. Patent Document 3 describes that if the amount of change in pupil diameter caused by light from a lighting unit installed in the vehicle is less than a predetermined value, the driver is determined to be in a tense state, and if the amount of change in pupil diameter caused by light from a lighting unit installed in the vehicle is equal to or greater than a predetermined value, the driver is determined to be in a relaxed state.

The above-mentioned Patent Document 4 discloses an information processing device that uses the detection results of the user's pupil diameter and eyelid opening and closing interval to determine the user's stress level. The above-mentioned Patent Document 4 describes that image recognition is performed on a captured image of the user's eyes to detect the user's eye movements such as the pupil diameter and eyelid opening and closing interval, and the presence or absence of the user's stress symptoms is determined based on the detection results.

Patent Document 5 discloses a driver condition determination device that determines whether or not the driver is aware of a sense of danger. Patent Document 5 describes that the device detects whether or not the driver's heart rate is continuously increasing and whether or not the driver's blink interval is longer than necessary, and determines whether or not the driver is aware of a sense of danger based on these detection results.

International Publication No. 2018/100875 JP 2009-113622 A JP 2016-139258 A JP 2019-40495 A JP 2015-32005 A

The above Patent Documents 1 to 5 disclose technologies that provide driving assistance based on biological information such as changes in the driver's pupil diameter. However, due to sunlight from the setting sun and light sources of headlights from oncoming vehicles that are highly incident from one direction, the brightness outside the vehicle and the brightness inside the vehicle may not be equivalent. For example, the brightness actually perceived by the driver may not be detected using only information from an exterior illuminance sensor that controls headlights located in a specified position.

As described above, when trying to obtain a decline in the driver's own cognitive function from changes in the driver's pupil diameter, it is difficult to perform pupil diameter calibration in the light and dark outside the vehicle. This raises the concern that a misjudgment may be made because it is not possible to distinguish between changes in pupil diameter due to disturbance light and changes in pupil diameter due to the driver's decline in cognitive function, resulting in an inability to accurately judge the driver's condition.

On the other hand, it is possible to accurately obtain the illuminance state inside the vehicle cabin by installing multiple illuminance sensors near the driver inside the vehicle cabin, but this has the problem of being costly.

The present invention has been made to solve the above problems, and aims to provide a vehicle driver condition determination device that can accurately determine the driver's condition while preventing costs from increasing.

To achieve the above objective, the present invention is configured as follows:

(1) The driver state determination device of the present invention includes an imaging unit that images the driver of the vehicle, a pupil diameter detection unit that detects information related to the driver's pupil diameter from an image acquired by imaging with the imaging unit, an eye open state detection unit that detects information related to the position of the driver's eyelids, and a driver state determination unit that performs a state determination process to determine the state of the driver based on the information related to the pupil diameter detected by the pupil diameter detection unit and the information related to the eyelid position detected by the eye open state detection unit, and the driver state determination unit is characterized in that, on the condition that the change in the pupil diameter and the change in the eyelid position due to the closing of the eyelids are synchronized, the information related to the pupil diameter and the information related to the eyelid position detected at the time of synchronization are excluded from the target of the state determination process.

According to the above configuration, when the change in the pupil diameter and the change in the eyelid position of the driver are synchronized at the reflex level (reflexive blinking, etc.), it can be determined that the change is due to the influence of light or the like entering the driver's eyes (disturbance factor). As a result, when the change in the pupil diameter and the change in the eyelid position are synchronized, the change in the pupil diameter can be determined not to be due to the driver's fatigue or decline in cognitive function, etc. As a result, the driver's condition can be accurately determined. Furthermore, since it is no longer necessary to install a separate device, etc. for accurately acquiring the illuminance condition inside the vehicle cabin, it is possible to suppress high costs.

(2) In the driver state determination device for a vehicle according to the present invention, preferably, the eye-open state detection unit is capable of deriving an eyelid closure rate based on the eyelid position, and the driver state determination unit determines that a change in eyelid position has occurred due to the eyelids being closed based on the eyelid closure rate and the duration for which the closure rate continues at or above a predetermined value. With this configuration, it is possible to accurately determine whether a change in the driver's eyelid position is normal or abnormal based on the eyelid closure rate and duration.

(3) In this case, preferably, the driver state determination unit may exclude the information related to the pupil diameter and the information related to the eyelid position detected at the time of synchronization from the target of the state determination process, on the condition that the change in the pupil diameter and the change in the eyelid position are synchronized when the reduction rate before and after the change in the pupil diameter is equal to or greater than a first threshold value and the reduction rate before and after the opening and closing of the eyelid position is equal to or greater than a second threshold value and continues for the duration. With this configuration, when the change in the pupil diameter and the change in the eyelid position are synchronized at the reduction rate and duration, etc., it is determined that the change in the driver's pupil diameter and the change in the eyelid position are due to a disturbance (disturbance factor) such as a light stimulus. Therefore, when there is a change in the pupil diameter and the change in the eyelid position as described above, it is possible to suppress an immediate erroneous determination that the driver's state is abnormal.

(4) In the driver state determination device of the present invention, preferably, an external illuminance sensor is further provided for detecting illuminance outside the vehicle, and the driver state determination unit may exclude the information related to the pupil diameter and the information related to the eyelid position from the state determination process on the condition that the external illuminance sensor detects that the illuminance outside the vehicle is equal to or greater than a predetermined illuminance value. With this configuration, when the illuminance outside the vehicle is equal to or greater than a predetermined illuminance value, it can be determined that the driver's pupil diameter and eyelid position have changed reflexively due to a sudden increase in illuminance. As a result, it is possible to suppress erroneous determination that a change in the driver's pupil diameter and eyelid position due to a sudden increase in illuminance is an abnormal state.

According to the present invention, it is possible to provide a vehicle driver state determination device that can accurately determine the driver's state while preventing costs from increasing.

1 is a block diagram showing an overall configuration of a driver's state determination device for a vehicle according to an embodiment of the present invention; 1 is a graph for explaining a decline in cognitive function based on interpupillary distance (change in pupil diameter) according to this embodiment. 4 is a flowchart showing a state determination process in the driver state determination device for a vehicle according to the present embodiment. 4 is a flowchart showing a state determination process in the driver state determination device for a vehicle according to the present embodiment.

The following describes a vehicle driver state determination device according to one embodiment of the present invention with reference to the attached drawings. These drawings are schematic diagrams and are not necessarily drawn to exact scale. In addition, similar components are denoted by similar reference numerals in the drawings.

(Overall composition)
The overall configuration of a driver state determination device 100 for a vehicle according to this embodiment will be described with reference to Fig. 1. The driver state determination device 100 for a vehicle is applied (mounted) to vehicles in general, such as hybrid vehicles, electric vehicles, and self-driving cars. As shown in Fig. 1, the driver state determination device 100 for a vehicle includes an imaging unit 10, a sensor unit 20, a control unit 30, and a notification unit 40.

(Imaging unit)
The imaging unit 10 is mainly composed of a driver monitoring camera 10a. The driver monitoring camera 10a is composed of a camera unit such as a so-called drive recorder. The driver monitoring camera 10a is attached to, for example, the windshield or the rearview mirror in the vehicle cabin.

The driver monitoring camera 10a captures the face (particularly the area around the eyes) of the driver who is driving the vehicle. The driver monitoring camera 10a transmits image information (data) of the captured face of the driver to a calculation system 31 of the control unit 30, which will be described later. The driver monitoring camera 10a may also be equipped with an infrared light. This makes it possible to capture a clear image of the driver's face even in a dark vehicle interior, such as when driving at night.

(Sensor section)
The sensor unit 20 is mainly composed of an exterior illuminance sensor 20a. The exterior illuminance sensor 20a is provided on the outer periphery of the vehicle and detects the illuminance outside the vehicle. The exterior illuminance sensor 20a transmits the detected illuminance information (data) outside the vehicle to a calculation system 31 of the control unit 30, which will be described later.

(Control Unit)
The control unit 30 is a control device or the like that controls the entire vehicle. The control unit 30 includes a calculation system 31 and a vehicle control system 32.

The calculation system 31 detects information related to the driver's pupil diameter and eyelid position based on the illuminance information detected by the external illuminance sensor 20a of the sensor unit 20 and the image information of the driver's face captured by the driver monitoring camera 10a of the imaging unit 10. Furthermore, the calculation system 31 determines whether the driver is in a normal state or an abnormal state based on the above information, and transmits the determination result to the vehicle control system 32.

The calculation system 31 includes a pupil diameter detection unit 31a, an eye open state detection unit 31b, and a driver state determination unit 31c.

The pupil diameter detection unit 31a detects information related to the driver's pupil diameter (e.g., the size of the pupil diameter and the rate of change due to enlargement and reduction of the pupil diameter, etc.) from the image information acquired by imaging with the driver monitoring camera 10a of the imaging unit 10.

The eye-open state detection unit 31b detects information related to the driver's eyelid position (e.g., the distance between the upper eyelid and the lower eyelid) from the image information acquired by imaging with the driver monitoring camera 10a of the imaging unit 10. The eye-open state detection unit 31b can also derive the eyelid closure rate based on the eyelid position. The eyelid closure rate refers to the rate of change in the distance of the eyelid in the blinking direction (vertical direction). The driver state determination unit 31c determines that a change in eyelid position (closing of eyelid position) has occurred due to the eyelids being closed, based on the eyelid closure rate and the duration for which the eyelid closure rate continues at or above a predetermined value.

Here, in this embodiment, the driver state determination unit 31c performs a state determination process to determine whether the driver is in a normal state or an abnormal state based on information related to the pupil diameter detected by the pupil diameter detection unit 31a and information related to the eyelid position detected by the eye-open state detection unit 31b. Also, in this embodiment, the driver state determination unit 31c performs a process to exclude information related to the pupil diameter and information related to the eyelid position detected at the time of synchronization from the state determination process, on the condition that the change in the pupil diameter and the change in the eyelid position due to the eyelids being closed are synchronized.

Specifically, the driver state determination unit 31c determines whether the change in pupil diameter and the change in eyelid position are synchronized when the reduction rate before and after the change in pupil diameter is equal to or greater than a first threshold (e.g., 15% or more) and the reduction rate before and after the opening and closing of the eyelid position (eyelid closure rate) is equal to or greater than a second threshold (e.g., 10% or more) and continues for a predetermined duration. The driver state determination unit 31c excludes information related to the pupil diameter and the eyelid position detected at the time of synchronization from the target of the state determination process, on the condition that the change in pupil diameter and the change in eyelid position are determined to be synchronized. This is because in the above case, the change in the driver's pupil diameter and the change in eyelid position are determined to be due to disturbance factors such as sunlight outside the vehicle or the light source of the headlights of an oncoming vehicle, and are not due to a decline in the driver's cognitive function (level of awareness).

Here, the determination of the decline in cognitive function in a driver will be described with reference to Figure 2. Figure 2 shows the change in the driver's interpupillary distance (change in pupil diameter) over time, with the horizontal axis showing time [min] and the vertical axis showing interpupillary distance [mm].

In FIG. 2, the interpupillary distance changes over time, repeating micro-vibrations. The interpupillary distance also varies in amplitude between a range of 5 min or less (monotonic pupil constriction) and a range of 5 min or more (low-frequency fluctuations), with the boundary being approximately 5 min. In other words, the amplitude of the interpupillary distance is greater in the range of 5 min or more than in the range of 5 min or less. Note that "monotonic pupil constriction" indicates a state before drowsiness occurs (normal state), and "low-frequency fluctuations" indicates a precursor to drowsiness or a state of high drowsiness (high drowsiness state).

When the driver's state of impaired cognitive function and state of high drowsiness are roughly equivalent (impaired cognitive function ≒ high drowsiness state), the impaired cognitive function causes monotonic pupil constriction and low-frequency fluctuations in pupil diameter. In this embodiment, as described above, by detecting information related to pupil diameter over time (changes in pupil diameter), it is possible to determine the impaired cognitive function of the driver from changes in pupil diameter.

As shown in FIG. 1, the driver state determination unit 31c excludes information related to pupil diameter and eyelid position from the state determination process on the condition that the exterior illuminance sensor 20a detects that the illuminance outside the vehicle is equal to or greater than a predetermined illuminance value. In the above case, the change in the driver's pupil diameter and eyelid position is determined to be a disturbance factor caused by sunlight outside the vehicle or the light source of the headlights of an oncoming vehicle.

The vehicle control system 32 is a control device that controls the vehicle based on the judgment result judged by the driver state judgment unit 31c of the calculation system 31. For example, on condition that the driver state judgment unit 31c judges that the driver is in a normal state, the vehicle control system 32 performs a process to continue the running of the vehicle. On the other hand, on condition that the driver state judgment unit 31c judges that the driver is in an abnormal state, the vehicle control system 32 performs a process to stop the vehicle and/or a process to output an alert to the notification unit 40.

(Notification Department)
The notification unit 40 is mainly composed of a speaker, an instrument panel, etc. When the driver is in an abnormal state (not in a normal state), the notification unit 40 notifies (warns) the driver audibly and visually by a buzzer, voice, light, text, etc.

(State Determination Process)
The state determination process in the driver state determination device for a vehicle according to this embodiment will be described with reference to FIGS. 1, 3, and 4. FIG.

As shown in FIG. 3, in step S10, the vehicle control system 32 controls the vehicle's running state. Then, the process proceeds to step S11.

In step S11, the vehicle exterior illuminance sensor 20a measures (detects) the illuminance outside the vehicle, and transmits illuminance information (data) outside the vehicle to the calculation system 31. Then, the process proceeds to step S12.

In step S12, the driver's face is captured by the driver monitoring camera 10a, and information related to the driver's pupil diameter and eyelid position is detected from the captured image. At this time, the information related to the pupil diameter is calibrated based on the illuminance information (data) outside the vehicle detected in step S11. For example, if a certain pupil diameter continues for a predetermined period of time due to the setting sun, etc., calibration is performed using that pupil diameter as a reference diameter, and the driver's state due to changes in pupil diameter is determined.

Information relating to pupil diameter is detected by the pupil diameter detection unit 31a from the image captured by the driver monitoring camera 10a. Information relating to eyelid position is detected by the eye open state detection unit 31b from the image captured by the driver monitoring camera 10a. Note that the processes in steps S11 and S12 are performed substantially simultaneously. Then, the process proceeds to step S13.

In step S13, the driver state determination unit 31c determines whether the reduction rate before and after the change in pupil diameter is equal to or greater than a first threshold value (e.g., 15% or greater). In step S13, if the driver state determination unit 31c determines that the reduction rate before and after the change in pupil diameter is not equal to or greater than 15% (less than 15%) (No), the process returns to step S10.

On the other hand, if the driver state determination unit 31c determines in step S13 that the reduction rate before and after the change in pupil diameter is 15% or more (Yes), the process proceeds to step S14.

In step S14, the driver state determination unit 31c determines whether the reduction rate (eyelid closure rate) of the eyelid position before and after opening and closing is equal to or greater than a second threshold value (e.g., 10% or greater) and whether the change in eyelid position continues for a predetermined duration.

In step S14, if the driver state determination unit 31c determines that the reduction rate of the eyelid position before and after opening and closing is not 10% or more (less than 10%), or that the change in eyelid position has not continued for a predetermined duration (No), the process returns to step S10.

On the other hand, in step S14, if the driver state determination unit 31c determines that the reduction rate of the eyelid position before and after opening and closing is 10% or more and that the change in eyelid position (closing of eyelid position) continues for a predetermined duration (Yes), the process proceeds to step S15 (see Figure 4).

The order of steps S13 and S14 may be reversed, or the respective steps may be performed substantially simultaneously. Furthermore, after it is determined in step S13 that the change in pupil diameter is a reduction of the first threshold or more, step S14 may be omitted and the process may proceed to step S15.

In step S15, the vehicle exterior illuminance sensor 20a detects the illuminance outside the vehicle, and the detected illuminance information (data) is transmitted to the calculation system 31 of the control unit 30. The driver state determination unit 31c of the calculation system 31 determines whether the illuminance detected by the vehicle exterior illuminance sensor 20a is equal to or greater than a predetermined illuminance value (rapid increase in illuminance).

In step S15, if the driver state determination unit 31c determines that the illuminance detected by the exterior illuminance sensor 20a is equal to or greater than the predetermined illuminance value (Yes), the process proceeds to step S16.

In step S16, it is determined that the change in the driver's pupil diameter and eyelid position is due to disturbances such as sunlight or the headlights of oncoming vehicles, and is not due to a decline in the driver's cognitive function. Therefore, information related to the driver's pupil diameter and information related to the eyelid position are excluded from the state determination process (determination canceled). Then, the process returns to step S10 (see FIG. 3).

On the other hand, if the driver state determination unit 31c determines in step S15 that the illuminance detected by the exterior illuminance sensor 20a is less than the predetermined illuminance value (No), the process proceeds to step S17.

In this embodiment, in step S17, the driver state determination unit 31c determines whether the change in the driver's pupil diameter and the change in eyelid position are synchronized. Note that the "synchronization" in step S17 may be set to, for example, the time of the reflex reaction level, which is about 0.1 seconds in this embodiment, but this time can be set appropriately. Also, in step S17, if the change in the pupil diameter and the change in the eyelid position are synchronized (Yes), the process proceeds to step S16.

In step S16, the driver state determination unit 31c determines that the change in the driver's pupil diameter and eyelid position is due to disturbance factors such as sunlight or the headlights of oncoming vehicles, and is not due to a decline in the driver's cognitive function, so information related to the driver's pupil diameter and information related to the eyelid position are excluded from the state determination process (determination canceled). Then, the process returns to step S10 (see FIG. 3).

On the other hand, in step S17, if the driver state determination unit 31c determines that the change in the driver's pupil diameter and the change in eyelid position are not synchronized (No), the process proceeds to step S18. In other words, this is the case when the change in the driver's pupil diameter and the change in eyelid position do not occur simultaneously.

In step S18, the driver state determination unit 31c determines that the driver's pupil diameter has changed (constricted). Then, the process proceeds to step S19.

In step S19, the driver state determination unit 31c determines whether the change in the driver's pupil diameter is abnormal. If the driver state determination unit 31c determines in step S19 that the change in the driver's pupil diameter is abnormal (Yes), the process proceeds to step S20. In this case, the change in pupil diameter is determined to be due to the driver's fatigue, a decline in cognitive function, or the like.

In step S20, vehicle control is performed by the vehicle control system 32. Specifically, the vehicle control system 32 performs a process of stopping the vehicle and/or a process of outputting an alert to the notification unit 40. Then, the process returns to step S10.

On the other hand, if it is determined in step S19 that the change in the driver's pupil diameter is not abnormal (No), the process proceeds to step S21. In step S21, the vehicle control system 32 performs processing to continue driving the vehicle. Then, the process returns to step S10.

The above-described embodiment provides the following advantages (1) to (4).

(1) In the vehicle driver state determination device 100 according to the above embodiment, information related to the pupil diameter and the eyelid position detected at the time of synchronization is excluded from the state determination process by the driver state determination unit 31c, provided that the change in the pupil diameter and the change in the eyelid position of the driver are synchronized. According to the above embodiment, when the change in the pupil diameter and the change in the eyelid position of the driver are synchronized at the reflex level (reflexive blinking, etc.), it can be determined that the change is due to the influence (disturbance factor) of light or the like entering the driver's eyes. As a result, when the change in the pupil diameter and the change in the eyelid position are synchronized, the change in the pupil diameter can be determined not to be due to the driver's fatigue or decline in cognitive function, etc. As a result, the driver's state can be accurately determined. Furthermore, since it is not necessary to separately install a device or the like for accurately acquiring the illuminance state in the vehicle cabin, it is possible to suppress high costs.

(2) In the vehicle driver state determination device 100 according to the above embodiment, a change in eyelid position is determined to have occurred due to the eyelids being closed when the eyelid closure rate is 10% or more and based on a predetermined duration. This makes it possible to accurately determine whether a change in the driver's eyelid position is normal or abnormal based on the eyelid closure rate and duration.

(3) In the vehicle driver state determination device 100 according to the above embodiment, when the reduction rate before and after the change in the driver's pupil diameter is equal to or greater than the first threshold (15% or greater) and the reduction rate before and after the opening and closing of the eyelid position is equal to or greater than the second threshold (10% or greater) and continues for a predetermined duration, the information related to the pupil diameter and the eyelid position detected at the time of synchronization is excluded from the target of the state determination process by the driver state determination unit 31c, provided that the change in pupil diameter and the change in eyelid position are synchronized. As a result, when the change in pupil diameter and the change in eyelid position are synchronized at the above reduction rate and duration, etc., it is determined that the change in the driver's pupil diameter and the change in eyelid position are due to a disturbance (disturbance factor) such as a light stimulus. Therefore, when the above-mentioned change in pupil diameter and change in eyelid position occur, it is possible to suppress an immediate erroneous determination that the driver's state is abnormal.

(4) In the driver state determination device 100 of the vehicle according to the above embodiment, information related to pupil diameter and information related to eyelid position are excluded from the state determination process by the driver state determination unit 31c on the condition that the exterior illuminance sensor 20a detects that the illuminance outside the vehicle is equal to or greater than a predetermined illuminance value. As a result, when the illuminance outside the vehicle is equal to or greater than the predetermined illuminance value, it can be determined that the driver's pupil diameter and eyelid position have changed reflexively due to a sudden increase in illuminance. As a result, it is possible to prevent the change in the driver's pupil diameter and eyelid position due to a sudden increase in illuminance from being erroneously determined to be an abnormal state.

(Modification)
The above embodiment can be modified as follows.

In the above embodiment, a driver monitoring camera is shown as an example of an imaging unit that captures an image of the driver of the vehicle, but the present invention is not limited to this. For example, an imaging unit other than a driver monitoring camera can be applied as long as it is capable of capturing an image of the driver of the vehicle.

In the above embodiment, an example is shown in which it is determined whether the reduction rate before and after the change in the driver's pupil diameter is equal to or greater than a first threshold value (e.g., 15% or greater), but the present invention is not limited to this. For example, it is also possible to set the first threshold value to a value other than 15%.

In the above embodiment, an example is shown in which it is determined whether the reduction rate before and after the change in the driver's eyelid position is equal to or greater than the second threshold (e.g., 10% or greater), but the present invention is not limited to this. For example, it is also possible to set the second threshold to a value other than 10%.

The above embodiments are merely examples of applications of the present invention, and it goes without saying that any other embodiments within the scope of the claims are also included within the technical scope of the invention.

10: Imaging unit 10a: Driver monitoring camera 20: Sensor unit 20a: Vehicle exterior illuminance sensor 30: Control unit 31: Calculation system 31a: Pupil diameter detection unit 31b: Eye open state detection unit 31c: Driver state determination unit 32: Vehicle control system 40: Notification unit 100: Vehicle driver state determination device

Claims (3)

An imaging unit that images a driver of the vehicle;
a pupil diameter detection unit that detects information related to a pupil diameter of the driver from an image acquired by the imaging unit, and an eye open state detection unit that detects information related to an eyelid position of the driver;
a driver state determination unit that performs a state determination process to determine a state of the driver based on information related to the pupil diameter detected by the pupil diameter detection unit and information related to the eyelid position detected by the eye open state detection unit,
the driver state determination unit excludes information related to the pupil diameter and information related to the eyelid position detected at the time of synchronization from targets of the state determination process on the condition that the change in the pupil diameter and the change in the eyelid position due to closing of the eyelids are synchronized,
the eye-open state detection unit is capable of deriving an eyelid closure rate based on the eyelid position,
the driver state determination unit determines that a change in eyelid position has occurred due to the eyelids being closed, based on the closure rate and a duration during which the closure rate continues to be equal to or greater than a predetermined value,
The driver's state determination device for a vehicle is characterized in that, when the reduction rate before and after the change in pupil diameter is equal to or greater than a first threshold value and the reduction rate before and after the opening and closing of the eyelid position is equal to or greater than a second threshold value and continues for the duration, the driver's state determination unit excludes information related to the pupil diameter and information related to the eyelid position detected at the time of synchronization, on the condition that the change in pupil diameter and the change in eyelid position are synchronized, from the target of the state determination processing . Further comprising an exterior illuminance sensor for detecting an illuminance outside the vehicle,
2. The driver's state determination device for a vehicle as described in claim 1, characterized in that, when the exterior illuminance sensor detects that the illuminance outside the vehicle is equal to or greater than a predetermined illuminance value, the driver's state determination unit excludes the information relating to the pupil diameter and the information relating to the eyelid position from the state determination processing. 3. The driver's state determination device for a vehicle according to claim 2, wherein the reference diameter related to the pupil diameter is calibrated based on illuminance information from the vehicle exterior illuminance sensor.

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