JP2019043301A - Wakefulness maintaining device and control program - Google Patents

Abstract

To make it possible to obtain a higher wakefulness effect.SOLUTION: This wakefulness maintaining device comprises: a main air conditioning part which generates cold air stimulation for awakening a driver; a stimulation control part 302 which generates cold air stimulation to an object part of the driver from a seat air-conditioning part; and a stimulation time control part 303 which controls an ON period during which cold air stimulation is generated and an OFF period during which cold air stimulation is discontinued. When the ON period is ended and the OFF period is started, the stimulation time control part 303 delays timing for generating a next cold air stimulation until a timing at which it is estimated that adaptation of the object part to cold air stimulation is recovered.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a wakefulness maintenance device and a control program for awakening a subject.

  2. Description of the Related Art Conventionally, a technique for stimulating a driver to awaken is known. For example, Patent Document 1 discloses a technique for directing cold air toward the ears and neck to prevent a person from falling asleep. Further, Patent Document 1 discloses a technique of repeating a cycle of starting an on-presentation period again after an on-presentation period in which the air blowing is continued, followed by an off period in which the air is turned off, corresponding to the on-presentation period. Is disclosed. In the technology disclosed in Patent Document 1, the adaptation of the human body to the stimulus in the on-presentation period is restored by interposing the off period between the on-presentation periods so that the awakening effect due to the ventilation is not reduced by the adaptation of the human body to the stimulus. Attempts to start stimulation for the next on-presentation period.

Japanese Patent No. 4682793

  However, in the technique disclosed in Patent Document 1, when the on-presentation period and the off-period are repeated for a long time, the skin temperature continues to decrease due to the cold air. Therefore, the on-presentation period even if the off-period corresponding to the on-presentation period is provided The human adaptation to the stimulation cannot be recovered. Therefore, there is a problem that the human body's perception with respect to the stimulation by the cold wind becomes dull and the awakening effect is lowered.

  One object of the present disclosure is to provide a wakefulness maintaining device and a control program that make it possible to obtain a higher wakefulness effect.

  The above object is achieved by a combination of the features described in the independent claims, and the subclaims define further advantageous embodiments of the invention. Reference numerals in parentheses described in the claims indicate a correspondence with specific means described in the embodiments described later as one aspect, and do not limit the technical scope of the present invention. .

  In order to achieve the above object, the wakefulness maintaining device of the present invention generates a wakeful stimulus to a target part of a subject from a stimulator (31, 32) that generates a wakeful stimulus for awakening the subject. A stimulus control unit (302); and a stimulus time control unit (303) for controlling a period for generating a wake stimulus and a period for pausing the wake stimulus. The stimulus time control unit ends a period for generating a wake stimulus. Then, when it becomes a period for suspending the arousal stimulus, the timing for generating the next arousal stimulus is delayed until it is estimated that the adaptation of the target part to the awakening stimulus is recovered.

  In order to achieve the above object, the control program of the present invention causes a computer to wake up a target part of a subject from a stimulating device (31, 32) that generates a wake-up stimulus for waking up the subject. When the stimulus control unit (302) that generates the stimulus, the period for generating the arousal stimulus and the period for stopping the arousal stimulus are controlled, and the period for generating the arousal stimulus is over and the period for stopping the arousal stimulus is reached Then, it is made to function as a stimulation time control unit (303) for delaying the timing for generating the next arousal stimulus until it is estimated that the adaptation of the target part to the arousal stimulus is recovered.

  According to this, when the period for generating an arousal stimulus is over and the period for suspending the arousal stimulus is reached, the next awakening stimulus is generated until it is estimated that the adaptation of the target part to the arousal stimulus is recovered. In each case, it waits until it is estimated that the adaptation to the wakeful stimulus in the period of generating the previous wakefulness stimulus is recovered, and starts the wakeful stimulus in the period of generating the next wakeful stimulus. . Therefore, even if the period for generating the arousal stimulus and the period for pausing the arousal stimulus are repeated for a long time, the next awakening is waited until adaptation to the arousal stimulus in the period for generating the arousal stimulus is recovered each time. It becomes possible to start the awakening stimulus in the period for generating the stimulus. Therefore, it becomes possible to suppress a decrease in the awakening effect due to insufficient recovery of adaptation, and a higher awakening effect can be obtained.

It is a figure which shows an example of a schematic structure of the awakening maintenance system. It is a figure which shows an example of a schematic structure of the air conditioner. 2 is a diagram illustrating an example of a schematic configuration of a main air conditioning unit 31. FIG. It is a figure which shows an example of a schematic structure of the sheet | seat air-conditioning part. It is a figure which shows an example of a schematic structure of air-conditioner ECU30. It is a flowchart which shows an example of the flow of the awakening stimulus related process in air-conditioner ECU30. It is a figure which shows the change of skin temperature when not recovering skin temperature by warm air stimulation with respect to cold wind stimulation. It is a figure which shows the change of skin temperature in the case of recovering skin temperature by warm air stimulation with respect to cold wind stimulation.

  A plurality of embodiments for disclosure will be described with reference to the drawings. For convenience of explanation, among the embodiments, parts having the same functions as those shown in the drawings used in the explanation so far may be given the same reference numerals and explanation thereof may be omitted. is there. For the parts denoted by the same reference numerals, the description in other embodiments can be referred to.

(Embodiment 1)
<Schematic configuration of wakefulness maintenance system 1>
Hereinafter, the present embodiment will be described with reference to the drawings. An awakening maintenance system 1 shown in FIG. 1 is used in an automobile (hereinafter simply referred to as a vehicle), and includes an HMI (Human Machine Interface) system 2 and an air conditioner 3. It is assumed that the HMI system 2 and the air conditioner 3 are connected to the in-vehicle LAN, for example. Hereinafter, a vehicle equipped with the awakening maintenance system 1 is referred to as a host vehicle.

  The HMI system 2 includes an HCU (Human Machine Interface Control Unit) 20, a DSM (Driver Status Monitor) 21, a biological sensor 22, and an operation device 23. The HMI system 2 accepts input operations from the driver of the host vehicle and monitors the state of the driver. This driver corresponds to the subject of the claims.

  The DSM 21 includes a near-infrared light source and a near-infrared camera, and a control unit that controls these. The DSM 21 is disposed, for example, on the upper surface of the instrument panel in a posture in which the near-infrared camera faces the driver's seat side of the own vehicle. The DSM 21 images a driver's head irradiated with near-infrared light from a near-infrared light source with a near-infrared camera. The image captured by the near-infrared camera is analyzed by the control unit. The control unit detects parts such as a face outline, eyes, nose, and mouth from the captured image by image recognition processing. Also, posture information such as the driver's face orientation and face position is detected from the relative positional relationship between the parts. Furthermore, the closed eye is detected by calculating the eyelid shape change as the eye opening degree. Then, the driver's arousal level (that is, the degree of drowsiness) is sequentially detected from the temporal change of the degree of eye opening, the shape characteristic of the facial part, the temporal change of the facial part, and the like. Therefore, this DSM 21 corresponds to the drowsiness detection device in the claims.

  In the present embodiment, the case where the DSM 21 detects the wakefulness by classifying into 6 levels of sleepiness of 0 to 5 will be described as an example. The level of sleepiness (hereinafter referred to as sleepiness level) divided into 6 levels is the sleepiness level “0” that seems to be completely sleepless (in other words, the sleepiness level) in descending order of the arousal level, in other words, the sleepiness level that seems to be slightly sleepy “1”, sleepy sleepiness level “2”, sleepy sleepiness level “3” quite sleepy, sleepiness level “4” very sleepy, sleepiness level (ie, sleep state) “5” And The DSM 21 sequentially outputs the detected drowsiness level to the HCU 20.

  The biometric sensor 22 measures the biometric information of the driver, and sequentially outputs the measured biometric information to the HCU 20. The biometric sensor 22 may be provided on the own vehicle such as provided on a steering wheel, a driver seat, or the like, or may be provided on a wearable device worn by the driver. When the biosensor 22 is provided in the wearable device worn by the driver, the HCU 20 may acquire the measurement result of the biosensor 22 via wireless communication, for example.

  As the biosensor 22, for example, a case where a temperature sensor that detects a driver's skin temperature is used as biometric information will be described as an example. The detection of the skin temperature by the temperature sensor may be performed by a method of detecting by contacting the driver, or by a method of detecting the driver without contact by using infrared rays radiated from the skin. . As an example, thermography or the like may be used.

  The operation device 23 is a switch group operated by the driver. For example, the operation device 23 includes a steering switch provided in a spoke portion of the steering of the own vehicle, a touch switch integrated with a display used in the own vehicle, and the like. In the present embodiment, the following description will be given on the assumption that the operation device 23 includes a switch (hereinafter referred to as a stimulus request switch) for requesting the driver to generate a stimulus for awakening (hereinafter referred to as an arousal stimulus).

  The HCU 20 is mainly configured by a microcomputer including a processor, a memory, an I / O, and a bus connecting them, and executes various processes by executing a control program stored in the memory. The memory here is a non-transitory tangible storage medium that stores computer-readable programs and data in a non-temporary manner. The non-transitional tangible storage medium is realized by a semiconductor memory or a magnetic disk.

  The HCU 20 detects a trigger (hereinafter referred to as a start trigger) for generating an arousal stimulus. When the start trigger is detected, the air conditioner 3 is notified that the start trigger has been detected. For example, the HCU 20 may be configured to detect this as a start trigger when the drowsiness level detected by the DSM 21 is greater than or equal to a threshold value. The threshold value referred to here is the degree of sleepiness that needs to be awakened when a driving operation is performed by a driver. For example, the threshold value may be a sleepiness level “2”.

  Moreover, what is necessary is just to make it the structure which HCU20 detects this as a start trigger, when operation which turns on the stimulus request switch of the operation devices 23 is received. The stimulus request switch may be turned on when the driver operates to turn on the wake-up stimulus when the driver wants to generate the wake-up stimulus at his own timing, and turned off when the driver does not need the wake-up stimulus. When the awakening maintenance system 1 is used in a vehicle capable of switching the automated driving automation level, the HCU 20 changes the automated driving automation level from a level where the driver is not obligated to monitor to a level where the driver is obligated to monitor. It is good also as a structure which detects switching as a start trigger.

  In addition, the HCU 20 sends the driver's sleepiness level sequentially detected by the DSM 21 to the air conditioner 3, and sends the driver's skin temperature sequentially measured by the biosensor 22 to the air conditioner 3.

  As shown in FIG. 2, the air conditioner 3 includes an air conditioner ECU 30, a main air conditioner 31, and a seat air conditioner 32. The air conditioner ECU 30 is mainly composed of a processor, a memory, an I / O, and a microcomputer having a bus connecting them, and executes a control program stored in the memory, thereby executing processing related to air conditioning of the host vehicle. Details of the air conditioner ECU 30 will be described later.

  The main air-conditioning unit 31 is controlled by the air-conditioner ECU 30 and performs adjustment (that is, air-conditioning) related to the air blown out from a plurality of air outlets provided in front of the driver's seat and the passenger seat in the passenger compartment. In the present embodiment, as an example, a case where air conditioning related to wind blown from a blow-out opening provided in front of a driver's seat is performed will be described. As an example, as shown in FIG. 3, the main air conditioning unit 31 includes a blower 310, a temperature adjustment unit 311, a blowout port 312 a, a blowout port 312 b, and a duct 313.

  The blower unit 310 rotationally drives the blower by a blower motor controlled by an instruction from the air conditioner ECU 30 to generate an air flow toward the vehicle interior in the duct 313. The duct 313 is provided with a temperature adjusting unit 311 for heating and cooling the air passing through the duct 313. The temperature adjustment unit 311 includes a heat exchanger such as a heater core, for example, and adjusts the temperature of the air by heating and cooling the air passing through the temperature adjustment unit 321 according to an instruction from the air conditioner ECU 30.

  The blowout port 312a is a so-called center face blowout port on the driver's seat side, and is arranged near the center of the instrument panel in the vehicle width direction so as to face the upper body side of the driver seated on the driver's seat. Then, the conditioned air heated and cooled by the temperature adjusting unit 311 that is blown through the duct 313 is applied to, for example, the left hand of the driver sitting on the seat. The air outlet 312b is a so-called side face air outlet on the driver's seat side, and is arranged on the side window side of the instrument panel so as to face the upper body side of the driver seated in the driver's seat. Then, the conditioned air heated and cooled by the temperature adjusting unit 311 that is blown through the duct 313 is applied to, for example, the right hand of the driver sitting on the seat.

  Note that the direction of the conditioned air blown from the outlets 312a and 312b may be adjustable by driving the louvers provided in the outlets 312a and 312b in accordance with instructions from the air conditioner ECU 30. 2 shows a configuration in which the main air-conditioning unit 31 is provided with the temperature adjusting unit 311 and the duct 313 corresponding to each of the blowout port 312a and the blowout port 312b, but is not necessarily limited thereto. For example, the air outlet 312a and the air outlet 312b may be configured to use the common temperature adjusting unit 311 and the duct 313.

  The seat air-conditioning unit 32 is disposed inside the seat, and performs air-conditioning for the passenger seated on the seat via the seat. The seat air conditioning unit 32 is also controlled by the air conditioner ECU 30 to perform air conditioning. In the present embodiment, the case where the seat air-conditioning unit 32 is arranged in the driver's seat will be described as an example. As an example, as shown in FIG. 4, the seat air-conditioning unit 32 includes a blower unit 320, a temperature adjustment unit 321, a blowout port 322, a blowout port 323, and a duct 324.

  The air blowing unit 320 sucks air outside the seat and blows it to the duct 324 side. The air passage includes a case forming an air passage, a driving motor controlled by an instruction from the air conditioner ECU 30, and air blowing driven by the driving motor. Have a fan. The air blowing unit 320 and the temperature adjusting unit 321 are connected by a duct 324. The temperature adjustment unit 321 includes a heat exchanger such as a Peltier element, and performs air temperature adjustment by heating and cooling the air passing through the temperature adjustment unit 321 according to an instruction from the air conditioner ECU 30.

  The air outlets 322 are a pair of air outlets provided on both right and left ends of the headrest of the seat. Even if the air outlets 322 are provided in the headrest, the air outlets 322 are fixed to the upper end portion of the seat back portion separately from the headrest. May be configured to be fixedly arranged. The blowout direction of the blowout port 322 is directed so that the conditioned air blown from the blowout port 322 hits the left and right ears and neck of the driver sitting on the seat. As a result, the conditioned air heated and cooled by the temperature adjusting unit 321 that is blown through the duct 324 is applied to the ears and neck of the driver sitting on the seat.

  The air outlet 323 is a pair of air outlets provided on the left and right ends of the seat back portion of the seat, and even if the air outlet 323 is configured in the seat back portion, the seat back portion is separated from the seat back portion. It may be configured to be fixedly disposed on the left and right ends by a fixing tool. The blowing direction of the blowing port 323 is directed so that the left and right arms of the driver sitting on the seat are conditioned by the conditioned air blown from the blowing port 323. As a result, the conditioned air heated and cooled by the temperature adjusting unit 321 that is blown through the duct 324 is applied to the arm of the driver sitting on the seat.

<Schematic configuration of air conditioner ECU 30>
Next, a schematic configuration of the air conditioner ECU 30 will be described with reference to FIG. The air conditioner ECU 30 includes a biological information acquisition unit 301, a stimulation control unit 302, a stimulation time control unit 303, a temperature control unit 304, and a timing specifying unit 305 as functional blocks. Note that some or all of the functions executed by the air conditioner ECU 30 may be configured in hardware by one or a plurality of ICs. Further, some or all of the functional blocks provided in the air conditioner ECU 30 may be realized by a combination of execution of software by a processor and hardware members.

  The biometric information acquisition unit 301 acquires the skin temperature of the target region of the driver. As an example, the configuration may be such that the skin temperature of the driver that is sequentially measured by the biosensor 22 is acquired from the HCU 20. When the target part is an arm, for example, the arm temperature may be obtained by estimating the skin temperature of the arm from the skin temperature measured by the biosensor 22 as a wearable device attached to the wrist. The estimation of the skin temperature of the arm from the skin temperature of the wrist may be performed based on the tendency of the skin temperature difference between the wrist and the arm obtained in advance by experiments or the like. When the target part is a hand, the skin temperature of the hand measured by the biological sensor 22 as a temperature sensor provided on the steering wheel may be acquired. In the case where the target site is the parotis or the neck muscle, the skin temperature of the parotid or neck muscle measured by the biosensor 22 as a thermography for measuring the thermal image of the head may be acquired.

  When the DSM 21 also functions as a radiation thermometer, the skin temperature of the driver's ear and neck muscles measured by the DSM 21 by the function of the radiation thermometer may be acquired via the HCU 20. . Moreover, although the biometric information acquisition part 301 shows the structure which acquires biometric information, such as a driver | operator's skin temperature, via HCU20 in this embodiment, it does not necessarily restrict to this. For example, the biometric information acquisition unit 301 may directly acquire biometric information such as the skin temperature of the driver from the DSM 21, the biosensor 22, and the like.

  The stimulation control unit 302 controls the period in which the conditioned air is generated from the main air conditioning unit 31 and the seat air conditioning unit 32 by the stimulation time control unit 303, and is generated from the main air conditioning unit 31 and the seat air conditioning unit 32 by the temperature control unit 304. Controls the temperature of the conditioned air.

  When a start trigger is input from the HCU 20, the stimulus control unit 302 starts awakening stimulation on the target region of the driver as having detected the start trigger. In the present embodiment, the awakening stimulus is cold air generated from the main air conditioning unit 31 and the seat air conditioning unit 32. Therefore, the main air-conditioning unit 31 and the seat air-conditioning unit 32 correspond to the stimulating device of the claims. As an example, the temperature of the cold air may be 18 ° C. The temperature of the cold air may be set to be lower as the room temperature becomes lower, for example.

  In the present embodiment, cold air is generated from the outlets 312a and 312b of the main air conditioning unit 31 toward the driver's hand, and from the outlets 322 of the seat air conditioning unit 32, the driver's ears, neck, and outlet 323. Will be described with reference to an example in which cold air is generated toward the driver's arm. This is only an example, and the arousal stimulus may be configured to be performed on a part of the target part described above, or may be configured to be performed on a target part other than the above-described target part.

  In addition, after starting the arousal stimulus, the stimulus control unit 302 has a period for performing the arousal stimulus (hereinafter referred to as an on period) and a period for suspending the arousal stimulus (an off period) until the timing for ending the arousal stimulus is reached. Repeat. In the present embodiment, it is assumed that the stimulus control unit 302 may cause stimulation by warm air that is air-conditioned air other than the awakening stimulus in the off period. The stimulus control unit 302 may be configured to constantly generate awakening stimuli during the ON period, or may be configured to generate intermittently.

  In addition, the stimulus control unit 302 varies the off period according to the driver's sleepiness level acquired from the HCU 20 and the skin temperature acquired by the biometric information acquisition unit 301, or changes the mode of warm air stimulation in the off period. Or change it. Details will be described later.

  When the ON period ends and the OFF period is reached, the timing specifying unit 305 uses a reference value (hereinafter referred to as a reference value) before the skin temperature acquired by the biological information acquisition unit 301 causes the stimulation control unit 302 to generate cold air. Based on the return to T0), the timing (hereinafter referred to as the recovery timing) estimated to recover the adaptation of the target part to the cold air is specified. Note that adaptation to cold air indicates that perception of cold air becomes dull as a result of habituation to cold air stimulation (hereinafter referred to as cold air stimulation). When the on period ends and the off period is reached, the stimulation control unit 302 causes the stimulation time control unit 303 to generate the next awakening stimulus until the recovery timing identified by the timing identification unit 305 (that is, the next period) On-period).

<Awakening stimulus related processing in the air conditioner ECU 30>
Next, an example of a flow of processing related to control for generating cold air stimulation in the air conditioner ECU 30 (hereinafter, awakening stimulation related processing) will be described using the flowchart of FIG. The flowchart in FIG. 6 may be configured to start when, for example, the ignition power of the own vehicle is turned on. For example, the awakening stimulus related process may be configured to be executed for each target part of the driver.

  First, in step S1, when a start trigger is input from the HCU 20 (YES in S1), the process proceeds to step S2. On the other hand, when the start trigger is not input (NO in S1), the process of S1 is repeated. In step S2, the biological information acquisition unit 301 acquires the skin temperature of the target region of the driver, and temporarily stores the acquired skin temperature in the memory of the air conditioner ECU 30 as a reference value T0 that serves as a reference for the target region. The T0 for each target part may be updated every time a new reference value for the target part is obtained.

  In step S3, when the driver's sleepiness level acquired from the HCU 20 is equal to or higher than the threshold (YES in S3), the process proceeds to step S7. On the other hand, when it is less than the threshold value (NO in S3), the process proceeds to step S4. The threshold value here may be a sleepiness level “2”, for example, similarly to the threshold value described above.

  In step S <b> 4, the stimulation control unit 302 causes cold air stimulation to the target site. The temperature of the cold air may be 18 ° C., for example, and the temperature control unit 304 controls the temperature of the cold air. The stimulation time control unit 303 controls the on period in which the cold air stimulation is performed. The stimulation time control unit 303 sets the on period to, for example, 30 seconds, and stops the cold air stimulation when 30 seconds have elapsed after starting the cold air stimulation, and shifts to the off period. In the off period when the cold air stimulation is performed in S4, the skin temperature of the target site returns toward T0 at room temperature.

  In step S5, the timing specifying unit 305 determines whether the skin temperature acquired by the biometric information acquisition unit 301 is stable within a range that can be approximated to T0. The range that can be approximated to T0 may be a value that is about an error, and can be arbitrarily set. In addition, as to whether or not it is stable, it is determined that the skin temperature acquired by the biological information acquisition unit 301 is within a range that can be approximated to T0 for a predetermined time that can be arbitrarily set. do it.

  If it is determined that the skin temperature is stable at T0 (YES in S5), the recovery timing is specified, the process proceeds to step S6, and if it is not the end timing of the arousal stimulation related process, the next cold air stimulation is performed. The stimulus control unit 302 starts. On the other hand, when it is determined that the skin temperature is not stable at T0 (NO in S5), the stimulation time control unit 303 continues the off period and repeats the process of S5. That is, the timing at which the stimulation time control unit 303 generates the next awakening stimulus is delayed until the timing identification unit 305 identifies the recovery timing.

  In step S6, when it is the end timing of the wakefulness stimulus related process (YES in S6), the wakefulness stimulus related process is ended. On the other hand, if it is not the end timing of the arousal stimulus related process (NO in S6), the process returns to S2 and the process is repeated. As an example of the end timing of the arousal stimulus related processing, the driver's sleepiness level acquired from the HCU 20 is 0, the stimulus request switch is turned off, and the like.

  In step S7 performed when the driver's drowsiness level is equal to or higher than the threshold value in S3, the temperature of the hot air that the stimulation control unit 302 is scheduled to generate during the off period is higher than T0 acquired in S2 (S7). YES, that is, if the driver is a driver whose T0 is lower than the warm air scheduled to be generated during the off period and the skin temperature of the target part is low, the process proceeds to step S13. On the other hand, when the temperature of the hot air is equal to or lower than T0 (NO in S7), that is, when the driver is a driver whose T0 is higher than the hot air scheduled to be generated during the off period and the skin temperature of the target site is high. , Go to S8. The temperature of the warm air scheduled to be generated during the off period may be 31.2 ° C., for example.

  In step S8, similarly to S4, the stimulation control unit 302 causes the cold air stimulation to the target site. In step S9, the timing specifying unit 305 determines whether or not the skin temperature acquired by the biological information acquisition unit 301 is equal to or higher than T0. And when it determines with skin temperature not having become more than T0 (it is NO at S9), the stimulation time control part 303 continues an OFF period, and moves to step S10. On the other hand, if it is determined in S9 that the skin temperature has become equal to or higher than T0 (YES in S9), the process proceeds to step S11.

  In step S <b> 10, the stimulus control unit 302 causes warm air stimulation to the target site, and repeats the process of S <b> 9. Therefore, the processing of S9 to S10 is repeated until the skin temperature becomes equal to or higher than T0 due to the warm air stimulation, and the warm air stimulation is continued. If it is determined in S9 that the skin temperature has become equal to or higher than T0, the warm air stimulation ends. Note that the temperature of the hot air may be 31.2 ° C. as described above, and the temperature control unit 304 controls the temperature of the hot air. In the off period when the cool air stimulation is performed in S8, the skin temperature of the target part returns toward T0 by the warm air stimulation.

  In step S11, in the same manner as in S5, when the timing specifying unit 305 determines that the skin temperature is stable at T0 (YES in S11), the recovery timing is specified, and the process proceeds to step S6, where the arousal stimulation is performed. If it is not the end timing of the related processing, the stimulation control unit 302 starts the next cold air stimulation. On the other hand, when it is determined that the skin temperature is not stable at T0 (NO in S11), the stimulation time control unit 303 continues the off period and proceeds to step S12. In step S12, warm air stimulation is not performed on the target part, and the process of S11 is repeated by leaving it at room temperature. In the processing of S9 to S12, the timing at which the stimulation time control unit 303 generates the next awakening stimulus is delayed until the timing specifying unit 305 specifies the recovery timing.

  In step S13, which is performed when the temperature of the hot air is higher than T0 in S7, the stimulation control unit 302 causes the cold air stimulation to be performed on the target part in the same manner as in S4. In step S14, the timing specifying unit 305 determines whether or not the skin temperature acquired by the biological information acquisition unit 301 is equal to or higher than T0 + α. And when it determines with skin temperature not being more than T0 + (alpha) (it is NO at S14), the stimulation time control part 303 continues an OFF period, and moves to step S15. On the other hand, if it is determined in S14 that the skin temperature is equal to or higher than T0 + α (YES in S14), the process proceeds to step S16.

  Here, α will be described. When the inventor is a driver whose T0 is higher than the warm air scheduled to be generated during the off period and the skin temperature of the target part is high, sleepiness increases when the warm air stimulation is performed until the skin temperature exceeds T0. I found a trend. On the other hand, if the driver is a driver whose T0 is lower than the warm air scheduled to be generated during the off period and whose skin temperature at the target site is lower, sleepiness may occur even if the warm air stimulation is performed until the skin temperature exceeds a certain level. I found out that there was a tendency to awaken without increasing. Therefore, for a driver whose skin temperature at the target site is low, the warm air stimulation is performed until the skin temperature becomes higher than a certain level than T0, so that adaptation is restored while giving an awakening effect. I also found out that Therefore, by setting a temperature equal to or higher than a certain value as α, it is possible to restore the adaptation to the cold air stimulus while giving the awakening effect. This α corresponds to a predetermined value in the claims, and in the example of the present embodiment, α may be 3 ° C., for example. As long as α is a positive value, the configuration in which the warm air stimulation is performed up to T0 + α performs the recovery of the adaptation to the cold wind stimulation while enhancing the awakening effect as compared with the configuration in which the warm air stimulation is performed up to T0. Has the effect of making

  In step S15, the stimulus control unit 302 causes warm air stimulation to the target part, and repeats the process of S14. Therefore, the processes of S14 to S15 are repeated until the skin temperature becomes equal to or higher than T0 + α by the warm air stimulation, and the warm air stimulation is continued. Note that the temperature of the hot air may be 31.2 ° C. as described above, and the temperature control unit 304 controls the temperature of the hot air. In the off period when the cold air stimulation is performed in S13, the skin temperature of the target site is increased toward T0 + α by the hot air stimulation.

  In step S16, in the same manner as in S5, when the timing identifying unit 305 determines that the skin temperature is stable at T0 (YES in S16), it is identified as a recovery timing, and the process proceeds to step S6, where arousal stimulation is performed. If it is not the end timing of the related processing, the stimulation control unit 302 starts the next cold air stimulation. On the other hand, when it is determined that the skin temperature is not stable at T0 (NO in S16), the stimulation time control unit 303 continues the off period and proceeds to step S17. In step S17, warm air stimulation is not performed on the target part, and the process of S16 is repeated by leaving it at room temperature. In the processes of S14 to S17, the timing at which the stimulation time control unit 303 generates the next awakening stimulus is delayed until the timing specifying unit 305 specifies the recovery timing. In the wakefulness stimulus related processing, the on period is a fixed period, while the off period is a period in which the skin temperature fluctuates until it stabilizes at T0.

  Here, the change of the skin temperature with respect to the cold stimulus will be described with reference to FIGS. The vertical axis in FIGS. 7 and 8 represents the skin temperature, and the horizontal axis represents the elapsed time. FIG. 7 shows changes in the skin temperature when the skin temperature is not recovered by the warm air stimulus with respect to the cold air stimulus as the awakening stimulus, and FIG. 8 shows the warm air against the cold air stimulus as the awakening stimulus. It shows changes in skin temperature when recovering skin temperature by stimulation. In the figure, the solid line arrows indicate the cold air stimulation period, the broken line arrows indicate the room temperature standing period, and the dotted line arrows indicate the hot air stimulation period.

  As shown in FIG. 7, when the skin temperature is not recovered by the warm air stimulation in response to the cold air stimulation, a process of performing the cold air stimulation again when the skin temperature is stabilized at T0 by leaving the room temperature after the cold air stimulation is performed. Will repeat. On the other hand, as shown in FIG. 8, when recovering the skin temperature by the warm air stimulation for the cold air stimulation, the warm air stimulation is performed for a certain period after the cold air stimulation, and the skin temperature is stabilized at T0 by being left at room temperature. Thereafter, the process of performing the cold air stimulation again is repeated. When warm air stimulation is performed, the recovery of skin temperature is accelerated, and the off period is shortened. Therefore, the frequency of the on period in the cycle of repeating the on period and the off period is increased, and the awakening effect is further enhanced. it can.

<Summary of Embodiment 1>
According to the configuration of the first embodiment, when the on-period for generating the arousal stimulus ends and the off-period for stopping the arousal stimulus is reached, the recovery timing estimated that the adaptation of the target part to the arousal stimulus is recovered. The timing for generating the next arousal stimulus is delayed. Therefore, in each case, the wake-up stimulus in the on-period in which the next wake-up stimulus is generated is started after waiting for the recovery timing estimated that the adaptation to the wake-up stimulus in the on-period in which the previous wake-up stimulus is generated is recovered. Therefore, even when the period for generating the arousal stimulus and the period for pausing the awakening stimulus are repeated for a long time, each time the next awakening is waited until the adaptation to the arousal stimulus in the period for generating the arousal stimulus is recovered. It becomes possible to start the awakening stimulus in the period for generating the stimulus. As a result, it is possible to suppress a reduction in the arousal effect due to insufficient recovery of adaptation to the arousal stimulus, and to obtain a higher arousal effect.

  Further, according to the configuration of the first embodiment, when the drowsiness level is equal to or higher than the threshold value, the frequency of the on period in the cycle in which the recovery from the adaptation to the cold air stimulation is accelerated by the hot air stimulation and the on period and the off period are repeated. To increase the awakening effect. Therefore, when the drowsiness level is high and the need for awakening is high, the awakening effect can be further enhanced.

  In addition, according to the configuration of the first embodiment, when the driver is a driver whose skin temperature at the target site is lower than the warm air scheduled to be generated during the off period, the skin temperature is lower than T0. By performing the warm air stimulation until the temperature rises above a certain temperature, it is possible to restore the adaptation to the cold air stimulation while providing an awakening effect. On the other hand, when the target person is a driver whose T0 is higher than the warm air scheduled to be generated during the off period and the skin temperature of the target part is high, the warm air stimulation is terminated when the skin temperature becomes T0 or higher. This makes it possible to restore adaptation to cold wind stimulation while suppressing the increase in sleepiness.

  Furthermore, according to the configuration of the first embodiment, since the awakening stimulus is generated when the start trigger is input to the air conditioner ECU 30, the driver becomes accustomed to the awakening stimulus compared to the configuration in which the awakening stimulus is always generated. Hateful.

(Embodiment 2)
In the first embodiment, the degree of drowsiness detected by the DSM 21 is greater than or equal to the threshold, the operation is accepted by the stimulus request switch, and the automatic driving automation level is switched to a level that the driver is obligated to monitor Although the configuration of detecting as a trigger has been shown, the configuration is not necessarily limited thereto. For example, only a part of the above may be detected as a start trigger. Alternatively, the start trigger may be that the voice recognition device recognizes the voice command that the driver requests to generate the arousal stimulus.

(Embodiment 3)
In the above-described embodiment, the configuration in which the awakening stimulus is started when the start trigger is input to the air conditioner ECU 30 is shown, but the configuration is not necessarily limited thereto. For example, it may be configured to start awakening stimulation when the ignition power of the own vehicle is turned on.

(Embodiment 4)
In the above-described embodiment, the configuration in which the drowsiness level of the driver is detected using the DSM 21 is described, but the present invention is not necessarily limited thereto. For example, it is good also as a structure which detects the degree of a driver's sleepiness from the measurement result measured with the biometric sensor 22. FIG. The detection of the degree of sleepiness from the measurement result measured by the biosensor 22 may be configured to be performed by the HCU 20, for example.

  Examples of the biosensor 22 used for detecting the degree of drowsiness and the measurement result include an electroencephalogram measured by an electroencephalograph, a heart rate measured by a heart rate monitor, a heart rate fluctuation, a pulse wave measured by a sphygmomanometer, and an electrodermal activity meter. There is skin conductance to measure. A known method may be used as a method for detecting the degree of sleepiness from the measurement result. The measuring device may be a wearable device that is worn by a driver and measures biological information, or may be provided on a steering wheel of a vehicle.

  In addition, it is good also as a structure which detects the degree of a driver's sleepiness from the information detected with the sensor mounted in the own vehicle. The detection of the degree of sleepiness from the information detected by the sensor mounted on the host vehicle may be configured to be performed by the HCU 20, for example. As an example of an in-vehicle sensor and information used for detecting the degree of drowsiness, there are a steering angle detected by a rudder angle sensor, a travel lane marking detected by a peripheral monitoring camera, and the like. A known method may be used as a method for detecting the degree of drowsiness from information detected by the in-vehicle sensor. For example, the degree of drowsiness can be detected from the rolling of the vehicle obtained from the position of the lane markings that are sequentially detected by the peripheral monitoring camera, or the amount of steering operation that is obtained from the steering angle that is sequentially detected by the rudder angle sensor. It is only necessary to detect the degree.

(Embodiment 5)
In the above-described embodiment, warm air stimulation is performed until the skin temperature becomes equal to or higher than T0 + α depending on whether or not the warm air scheduled to be generated in the off period is higher than T0, or the temperature is increased until the skin temperature becomes equal to or higher than T0. Although the structure which switches whether wind stimulation is performed was shown, it does not necessarily restrict to this. For example, regardless of whether or not T0 is higher than the warm air scheduled to be generated during the off period, the warm air stimulation may be performed until the skin temperature becomes equal to or higher than T0, or until the skin temperature becomes equal to or higher than T0 + α. It is good also as a structure which performs wind stimulation. In order to prevent the driver's sleepiness with a high skin temperature at the target site from being increased by warm air stimulation, the skin temperature does not matter whether T0 is higher than the warm air scheduled to be generated during the off period. It is preferable that warm air stimulation is performed until T0 or more.

(Embodiment 6)
In the above-described embodiment, the configuration in which whether or not to perform the warm air stimulation is illustrated depending on whether or not the drowsiness level of the driver who is the subject is equal to or higher than the threshold value is not necessarily limited thereto. For example, regardless of whether the drowsiness level is equal to or higher than a threshold value, the configuration may be such that the warm air stimulation is not performed, or the configuration where the warm air stimulation is performed. In order to further enhance the awakening effect, it is preferable to employ a configuration in which warm air stimulation is performed regardless of whether the drowsiness level is equal to or higher than a threshold value.

(Embodiment 7)
In the above-described embodiment, the cold air stimulus has been described as an example of the awakening stimulus, but is not necessarily limited thereto. As the awakening stimulus, in addition to the cold air stimulus, a stimulus using light emission, vibration, or the like may be used. The light emission may be configured to emit light of a wavelength that is considered to have an awakening effect from an LED or the like. The vibration may be configured to vibrate a vibrator provided at a location where the driver of the own vehicle contacts, such as a steering wheel or a driver seat.

  In the case where a stimulus by luminescence is used as the wakeful stimulus, the recovery of adaptation to the wakeful stimulus may be performed by stopping the stimulus by the luminescence. The recovery timing may be specified by the timing specifying unit 305 based on returning to the pupil size as a reference value before the on period.

  Further, in the case where a stimulus by vibration is used as the awakening stimulus, the recovery of adaptation to the awakening stimulus may be performed by stopping the stimulus by vibration. In addition, the recovery timing in the timing specifying unit 305 may be specified based on returning to the blood flow volume as a reference value before the blood flow volume in the target region is in the ON period. The blood flow rate may be configured to use a blood flow sensor or the like that measures the blood flow rate by laser Doppler flowmetry, for example.

(Embodiment 8)
In the above-described embodiment, the configuration in which the timing specifying unit 305 specifies the recovery timing based on the return of the biometric information such as the skin temperature to the reference value before the on period is shown, but the configuration is not necessarily limited thereto. For example, a recovery timing pattern unique to a person may be stored in advance, and the recovery timing may be specified from this pattern. In addition, this pattern may be configured to learn for each individual subject, or may be configured to be generalized by taking statistics of a plurality of subjects.

  As an example, as a pattern of recovery timing, a correspondence relationship in which time until recovery of adaptation is associated with the time of the arousal stimulus and the cumulative number of times of the arousal stimulus may be used by experiments or learning. And the timing specific | specification part 305 should just specify recovery | restoration timing from the time until the adaptation obtained with reference to this corresponding relationship is recovered based on the time of the wakefulness stimulus and the number of integration times of the wakefulness stimulus.

(Embodiment 9)
In the above-described embodiment, the configuration in which the awakening maintenance system 1 is used in an automobile has been shown, but the configuration is not necessarily limited thereto. The awakening maintenance system 1 can be used in various moving bodies. For example, the awakening maintenance system 1 may be configured to be used in a vehicle other than an automobile such as a railway vehicle or a motorbike, or a moving body other than a vehicle such as an aircraft or a ship. It is good also as a structure used by. Further, the present invention may be configured to be used in a room such as a house or facility other than a moving body. In this case, the target person who maintains the awakening state in the room corresponds to the target person in the claims. In addition, when adopting a configuration in which the present invention is used in a room such as a house or facility other than a moving body, a seat on which a subject person sits may be used instead of a driver's seat.

  The present invention is not limited to the above-described embodiments and modifications, and various modifications are possible within the scope of the claims, and technical means disclosed in different embodiments and modifications, respectively. Embodiments obtained by appropriately combining the above are also included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Awakening maintenance system, 2 HMI system, 3 Air conditioner, 20 HCU, 21 DSM (drowsiness detection device), 22 Biosensor, 23 Operation device, 30 Air-conditioner ECU (wakefulness maintenance device), 31 Main air-conditioning part (stimulation device), 32 seat air conditioning unit (stimulation device), 301 biological information acquisition unit, 302 stimulation control unit, 303 stimulation time control unit, 304 temperature control unit, 305 timing identification unit, 310 blower unit, 311 temperature adjustment unit, 312a outlet, 312b Air outlet, 313 duct, 320 Air blower, 321 Temperature adjustment part, 322 Air outlet, 323 Air outlet, 324 Duct

Claims (6)

A stimulation control unit (302) for generating the arousal stimulus from the stimulation device (31, 32) for generating an arousal stimulus for awakening the subject,
A stimulation time control unit (303) for controlling a period for generating the wakefulness stimulus and a period for suspending the wakefulness stimulus,
The stimulation time control unit, when the period for generating the arousal stimulus ends and the period for suspending the arousal stimulus is reached, until the timing at which the adaptation of the target site to the arousal stimulus is estimated to be recovered A wakefulness maintenance device for delaying the timing of generating the wakefulness stimulus. A biological information acquisition unit (301) for acquiring biological information of the subject;
Based on the fact that the biological information acquired by the biological information acquisition unit returns to a reference value used as a reference before generating the arousal stimulus, the timing at which the adaptation of the target part to the arousal stimulus is estimated to be recovered is determined. A timing specifying unit (305) for specifying,
The stimulation time control unit generates the next awakening stimulus until the timing specified by the timing specifying unit when the period for generating the awakening stimulus is ended and the period for stopping the awakening stimulus is reached. The wakefulness maintaining apparatus according to claim 1, wherein the timing is delayed.   In addition to generating cold air toward the target site as the arousal stimulus, the stimulus control unit can also generate hot air toward the target site, and the degree of sleepiness of the subject can be determined. When the degree of drowsiness detected using the drowsiness detection device (21) used for detection is equal to or greater than a threshold value, while generating warm air toward the target site during a period of pausing the arousal stimulus, The wakefulness maintaining apparatus according to claim 1, wherein when the degree of sleepiness is less than a threshold, warm air is not generated toward the target part in a period in which the wakefulness stimulation is suspended.   In addition to generating cold air toward the target site as the arousal stimulus, the stimulus control unit can also generate hot air toward the target site, and the degree of sleepiness of the subject can be determined. When the degree of drowsiness detected using the drowsiness detection device (21) used for detection is equal to or greater than a threshold value, while generating warm air toward the target site during a period of pausing the arousal stimulus, The wakefulness maintaining apparatus according to claim 2, wherein when the degree of sleepiness is less than a threshold value, warm air is not generated toward the target part in a period in which the wakefulness stimulation is suspended. The biological information acquisition unit acquires the skin temperature of the target site as the biological information,
The timing specifying unit specifies a timing at which the adaptation of the target part to the wakefulness stimulus is estimated to be recovered based on the skin temperature returning to the reference value before the wakefulness stimulus is generated. Yes,
When the degree of drowsiness is a threshold value or more and the skin temperature of the target part is equal to or higher than the temperature of the warm air, the stimulation control unit is directed toward the target part until the skin temperature becomes the reference value. While generating warm air, when the degree of drowsiness is equal to or higher than a threshold and the skin temperature of the target site is lower than the temperature of the hot air, the skin temperature is increased to a predetermined value or higher than the reference value. The wakefulness maintaining apparatus according to claim 4, wherein the warm air is generated toward a target site. Computer
A stimulation control unit (302) for generating the arousal stimulus from the stimulation device (31, 32) for generating an arousal stimulus for awakening the subject,
Controlling a period for generating the arousal stimulus and a period for stopping the arousal stimulus, and when the period for generating the arousal stimulus is over and the period for stopping the arousal stimulus is reached, the awakening of the target part A control program for functioning as a stimulation time control unit (303) for delaying the timing for generating the next awakening stimulus until the timing at which adaptation to the stimulus is estimated to be recovered.

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