JP2021111006A - Vehicle monitoring device - Google Patents

Abstract

To apply an effective awakening stimulation to a driver.SOLUTION: A vehicle monitoring device (10) includes: detection means (11) for detecting an awakening degree of a driver; and stimulation generation means (12) for applying at least one awakening stimulation among a plurality of kinds of awakening stimulation to a driver when a detected awakening degree is lowered. The stimulation generation means changes the kind of an awakening stimulation to be applied to a driver in accordance with duration of recovery of an awakening degree of the driver based on a detected awakening degree after applying at least one awakening stimulation to the driver.SELECTED DRAWING: Figure 1

Description

The present invention relates to the technical field of a vehicle monitoring device that monitors the arousal level of a driver when driving a vehicle.

As a device of this type, for example, a device that monitors the arousal level of the driver and gives the driver a dialogue as a stimulus for inducing self-issued behavior when the arousal level is low has been proposed (Patent Documents). 1). Further, a device has been proposed that detects the degree of drowsiness of the driver and presents an option for causing the driver to select the stimulus intensity of the arousal stimulus (see Patent Document 2).

JP-A-2010-187810 JP-A-2019-016160

In the technique described in Patent Document 1, for a driver who does not have the effect of dialogue as a stimulus, there is a possibility that recovery of alertness cannot be expected because there is no other stimulus option that can be taken. In the technique described in Patent Document 2, it is necessary for the driver to take action by himself / herself, and for example, the driver may feel annoyed or the effect of awakening the driver may not be obtained. As described above, there is room for improvement in the background technology described above.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle monitoring device capable of applying an effective arousal stimulus to a driver.

The vehicle monitoring device according to one aspect of the present invention comprises a detection means for detecting the arousal level of the driver and at least one awakening stimulus among a plurality of types of arousal stimuli when the detected arousal level decreases. The stimulus generating means includes a stimulus generating means to be applied to the driver, and the stimulus generating means is the duration of recovery of the arousal level of the driver based on the detected arousal level after applying the at least one arousal stimulus to the driver. The type of arousal stimulus applied to the driver is changed accordingly.

It is a block diagram which shows the structure of the vehicle which concerns on embodiment. It is a figure which shows an example of the time change of the arousal degree of a driver. This is an example of a table that defines the relationship between the degree of decrease in the driver's arousal level and the arousal stimulus applied to the driver. It is a flowchart which shows the operation of the support system ECU which concerns on embodiment.

An embodiment relating to a vehicle monitoring device will be described. The vehicle monitoring device according to the embodiment includes a detection means for detecting the arousal level of the driver. Since various existing modes such as a method of detecting the arousal level from the heart rate of the driver can be applied to the method of detecting the arousal degree, the detailed description thereof will be omitted.

The vehicle monitoring device includes a stimulus generating means for applying at least one of a plurality of types of arousal stimuli to the driver when the driver's arousal level is lowered. Examples of the arousal stimulus include a stimulus by light (blinking of light, etc.), a stimulus by sound (voice, music, warning sound, etc.), a physical stimulus (vibration, etc.), and the like.

The stimulus generating means changes the type of arousal stimulus applied to the driver according to the duration of recovery of the driver's arousal level after applying the at least one arousal stimulus to the driver. Here, the "duration of recovery of arousal level" means a period in which the arousal level after the arousal stimulus is applied is higher than the arousal level before the awakening stimulus is applied. If the duration of recovery was relatively short, it can be inferred that the effect of the added arousal stimulus on the driver was observed, but the effect was limited. If the duration of recovery is relatively long, it can be inferred that the added arousal stimulus was effective for the driver.

If the duration of recovery is relatively short, even if the same type of arousal stimulus is applied to the driver again, the driver may become accustomed to the arousal stimulus and may not have the effect of awakening the driver. Therefore, the stimulus generating means changes the type of arousal stimulus according to the duration of recovery. By adding a different type of arousal stimulus to the driver than the previously added arousal stimulus, it can be expected to awaken the driver while preventing the driver from becoming accustomed to the awakening stimulus. That is, according to the vehicle monitoring device, an effective awakening stimulus can be applied to the driver.

A support system ECU (Electronic Control Unit) 10 as a specific example of the vehicle monitoring device according to the embodiment will be described with reference to FIGS. 1 to 4. In FIG. 1, the support system ECU 10 is mounted on the vehicle 1.

In addition to the support system ECU 10, the vehicle 1 includes a driver monitor 21, a navigation device 22 including map information, a vehicle sensor 23, an omnidirectional sensor 24, switches and an operation system device 25, an engine ECU 31, a brake ECU 32, a steering ECU 33, and a light. Class 34, secondary abilities 35, and HMI (Human Machine Interface) class 36 are provided.

The secondary ability means a device that is not related to the running of the vehicle 1, such as an air conditioner and an audio device. In the present embodiment, it is assumed that the secondary ability 35 includes a HUD (Head-UP Display), a vibration generator, and a speaker. The vibration generator is configured to be able to vibrate the seat belt worn by the driver.

The driver monitor 21 may include, for example, a camera that images the interior of the vehicle 1, a biological monitor that measures vital signs such as the driver's heart rate, and the like. The support system ECU 10 is included in the secondary ability 35 so as to detect the arousal level of the driver based on the output of the driver monitor 21 and to apply an awakening stimulus to the driver when the arousal level of the driver is low. Controls the HUD, vibration generator, etc. That is, the support system ECU 10 functions as a so-called doze operation prevention device.

In addition, the driver monitor 21, the navigation device 22, the vehicle sensor 23, the omnidirectional sensor 24, the switches and the operation system device 25, the engine ECU 31, the brake ECU 32, the steering ECU 33, the lights 34, the secondary abilities 35, and the HMI 36. Since various existing aspects can be applied to the above, the detailed description thereof will be omitted.

The support system ECU 10 includes an arousal detection unit 11 and a stimulus generation unit 12 as a processing block logically realized or a processing circuit physically realized inside the support system ECU 10 in order to realize the above-mentioned functions. There is. The "alertness detection unit 11" and the "stimulation generation unit 12" correspond to the above-mentioned examples of the "detection means" and the "stimulation generation means", respectively.

The arousal level detection unit 11 detects the arousal level of the driver based on the output of the driver monitor 21. Since various existing modes can be applied to the method of detecting the arousal level, the detailed description thereof will be omitted. The arousal level of the driver decreases with the passage of time, for example, as shown in FIG. 2 (a). The stimulus generator 12 controls the HUD, vibration generator, and the like so as to apply an arousal stimulus to the driver when the driver's arousal level drops to a predetermined level.

The arousal stimulus will be described with reference to FIG. 3 in addition to FIG. 3 (a) to 3 (c) are examples of a table that defines the relationship between the degree of decrease in driver's alertness (that is, "alertness decrease level") and the arousal stimulus applied to the driver. It is assumed that the arousal reduction levels "1", "2" and "3" correspond to "L1", "L2" and "L3" in FIG. 2A, respectively.

When the arousal level of the driver drops to "L1" in FIG. 2 (a), the stimulus generator 12 causes the HUD so that the image displayed by the HUD blinks according to the table shown in FIG. 3 (a), for example. To control. At this time, the stimulus generating unit 12 may control the HUD so that the driver's eyeball saccade (that is, eyeball movement) is triggered.

When the driver's arousal level drops to "L2" in FIG. 2 (a), the stimulus generator 12 vibrates the seat belt worn by the driver according to, for example, the table shown in FIG. 3 (a). Control the vibration generator. At this time, the stimulus generating unit 12 may increase the tightening pressure by the seat belt in addition to vibrating the seat belt.

When the driver's arousal level drops to "L3" in FIG. 2 (a), the stimulus generator 12 sets the speaker so that a voice calling to the driver is emitted according to the table shown in FIG. 3 (a), for example. Control. At this time, the stimulus generation unit 12 may control the speaker so that a voice that raises a question to the driver (in other words, a voice that causes the driver's behavior) is emitted.

In the present embodiment, the type of arousal stimulus changes according to the degree of decrease in the arousal level of the driver. That is, in "L1" where the degree of decrease in alertness is relatively small, an indirect stimulus, for example, "HUD blinking" is selected. At "L2", where the degree of decrease in alertness is moderate, "seatbelt vibration", which is a direct stimulus experienced by the driver, is selected. In "L3", where the degree of decrease in alertness is relatively large, for example, "dialogue", which is a stimulus that encourages the driver's spontaneous behavior, is selected. In this way, by preparing a plurality of types of arousal stimuli according to the degree of decrease in the arousal level of the driver, it is possible to suppress the driver from being annoyed by the arousal stimuli.

For example, at each time T1 in FIGS. 2 (a) to 2 (c), the stimulus generator 12 causes the driver to follow the table shown in FIG. 3 (a) due to the driver's alertness dropping to “L1”. Suppose an arousal stimulus is applied.

In FIG. 2A, there is no particular change in the arousal level of the driver before and after the time T1. That is, in this case, it can be said that the arousal stimulus applied to the driver did not contribute to the recovery of the driver's arousal level (that is, the arousal stimulus had no effect). In this case, the stimulus generating unit 12 changes the intensity of the stimulus related to the blinking of the HUD of the arousal reduction level “1” to “strong”, for example, as shown in FIG. 3 (b).

In FIG. 2B, the driver's alertness is temporarily improved after the time T1. That is, in this case, it can be said that the arousal stimulus applied to the driver contributed to the recovery of the driver's arousal level, but the effect was limited. In this case, the stimulus generating unit 12 changes the type of stimulus of the arousal reduction level “1” from “HUD blinking” to “seat belt vibration”, for example, as shown in FIG. 3 (c).

In FIG. 2C, after the time T1, the driver's alertness remains higher than “L1” for a relatively long time. That is, in this case, it can be said that the arousal stimulus applied to the driver sufficiently contributed to the recovery of the driver's arousal level. In this case, the stimulus generator 12 maintains, for example, the table shown in FIG. 3 (a) (that is, no changes are made to the table).

The stimulus generating unit 12 is a table that has been changed when the power switch of the vehicle 1 is turned off or when the power switch is turned on (see, for example, FIGS. 3 (b) and 3 (c)). ) May be returned to the initial state. Alternatively, the stimulus generator 12 may return the modified table to the initial state when it detects that the driver has changed based on the output of the driver monitor 21. The stimulus generation unit 12 may simultaneously apply a plurality of types of arousal stimuli to the driver.

Next, the operation of the support system ECU 10 configured as described above will be described with reference to the flowchart of FIG.

In FIG. 4, the alertness detection unit 11 of the support system ECU 10 detects the alertness of the driver based on the output of the driver monitor 21. The stimulus generation unit 12 of the support system ECU 10 determines the degree of arousal degree based on the detected arousal degree (step S101).

The stimulus generation unit 12 determines whether or not the driver's alertness has decreased to a predetermined level (for example, any of "L1", "L2", and "L3" in FIG. 2A) (step S102). ). When it is determined in the process of step S102 that the arousal level of the driver has not decreased to a predetermined level (step S102: No), the operation shown in FIG. 4 is temporarily terminated. Then, after a predetermined period (for example, several tens of milliseconds to several hundreds of milliseconds) has elapsed, the process of step S101 is performed. That is, the operation shown in FIG. 4 is repeatedly performed at a cycle corresponding to a predetermined period.

When it is determined in the process of step S102 that the driver's arousal level has dropped to a predetermined level (step S102: Yes), the stimulus generator 12 responds to the driver's arousal level according to, for example, the table shown in FIG. An arousal stimulus is added to the driver (step S103). After that, the stimulus generation unit 12 determines the degree of arousal degree based on the arousal degree detected by the arousal degree detection unit 11 (step S104).

The stimulus generation unit 12 determines whether or not the driver's alertness has recovered (step S105). The stimulus generation unit 12 may determine that the arousal level has recovered, for example, when the arousal level is higher than a predetermined value as compared with the arousal level before the awakening stimulus is applied to the driver.

When it is determined in the process of step S105 that the arousal level has not recovered (step S105: No), the stimulus generating unit 12 increases the intensity of the arousal stimulus applied to the driver in the process of step S103. Change (step S107). Then, after the predetermined period has elapsed, the process of step S101 is performed.

When it is determined in the process of step S105 that the alertness has recovered (step S105: Yes), the stimulus generating unit 12 determines whether or not the recovery of the driver's alertness is maintained (step S106). The stimulus generation unit 12 may determine that the recovery of the arousal level is maintained, for example, when it can be estimated that the duration of the recovery described above is longer than a predetermined time.

When it is determined in the process of step S106 that the recovery of the arousal level is not maintained (step S106: No), the stimulus generator 12 applies the awakening stimulus applied to the driver in the process of step S103 to the awakening stimulus. Change to a different type of arousal stimulus (step S108). Then, after the predetermined period has elapsed, the process of step S101 is performed.

When it is determined in the process of step S106 that the recovery of the arousal level is maintained (step S106: Yes), the operation shown in FIG. 4 is temporarily terminated. Then, after the predetermined period has elapsed, the process of step S101 is performed.

(Technical effect)
In the support system ECU 10, for example, as shown in FIG. 3A, as the arousal level of the driver decreases, an awakening stimulus that acts more strongly on the driver is selected. Also, if the driver's arousal level is only temporarily improved by the arousal stimulus, the awakening stimulus that caused the increase in the arousal level is changed to a different type of arousal stimulus. Therefore, it is possible to prevent the awakening stimulus that is ineffective for the driver from being repeatedly performed, and it is possible to effectively apply the awakening stimulus to the driver.

In addition, when the degree of decrease in the driver's arousal level is relatively small, an indirect stimulus is selected as the arousal stimulus, and as the degree of decrease increases, a direct stimulus or the driver's spontaneous stimulus is gradually performed. A stimulus that promotes behavior is selected as an arousal stimulus. With this configuration, it is possible to suppress the application of an unnecessarily strong arousal stimulus to the driver while applying an arousal stimulus that maintains the driver's arousal level. As a result, it is possible to prevent the driver from feeling annoyed due to the arousal stimulus.

Various aspects of the invention derived from the embodiments described above will be described below.

The vehicle monitoring device according to one aspect of the present invention includes a detection means for detecting the arousal level of the driver and the driver for at least one awakening stimulus among a plurality of types of arousal stimuli when the detected arousal level decreases. The stimulus generating means comprises, after applying the at least one arousal stimulus to the driver, the duration of recovery of the arousal level of the driver based on the detected arousal level. The type of arousal stimulus applied to the driver is changed accordingly.

The present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of claims and within the scope not contrary to the gist or idea of the invention that can be read from the entire specification. The device is also included in the technical scope of the present invention.

1 ... Vehicle, 10 ... Support system ECU, 11 ... Alertness detection unit, 12 ... Stimulation generation unit

Claims (1)

A detection means that detects the alertness of the driver,
A stimulus generating means for adding at least one of a plurality of types of arousal stimuli to the driver when the detected arousal level decreases.
With
The stimulus generating means of the arousal stimulus to be applied to the driver according to the duration of recovery of the arousal level of the driver based on the detected arousal level after applying the at least one arousal stimulus to the driver. A vehicle monitoring device characterized by changing the type.

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