Vehicle seat, seat system, vehicle seat control method, and vehicle seat control program

Abstract

To provide a vehicle seat capable of guiding a driver to a state suitable for driving operation, a seat system including the vehicle seat, a control method of the vehicle seat, and a control program of the vehicle seat.SOLUTION: A vehicle seat 1 includes a seat main body 41 on which a driver is seated, a vibration device 42 provided on the seat main body, and a control device 43 that acquires a heart rate of the driver and controls driving of the vibration device, and when the heart rate is larger than a predetermined upper-threshold value n2, the control device executes guidance control for vibrating the vibration device at a vibration frequency corresponding to the heart rate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle seat, a seat system including a vehicle seat, a control method for a vehicle seat, and a control program for a vehicle seat. [Background technology]

[0002] Patent Document 1 discloses a vehicle seat mounted on an autonomously driven vehicle. The vehicle seat includes a sensor that detects the driver's level of alertness, a vibration source that generates vibrations to wake the driver, and a control device that controls the operation of the vibration source based on the detection results of the sensor. When transitioning from autonomous driving to manual driving, the control device acquires the driver's level of alertness from the sensor and determines whether the driver is capable of manual driving. If the control device determines that the driver is not capable of manual driving, it controls the operation of the vibration source to generate vibrations to wake the driver. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-6151 Summary of the Invention [Problem to be solved by the invention]

[0004] Even if a driver is awake, if the driver is in an extremely tense or excited state, there is a risk that driving operations will be delayed or that the driver's judgment and cognitive abilities will be impaired. Therefore, there is a need for the development of technology that can guide the driver into a state suitable for driving operations even when the driver is in a tense state.

[0005] In view of the above background, an object of the present invention is to provide a vehicle seat that can guide a driver into a state suitable for driving operations, a seat system including the vehicle seat, a control method for the vehicle seat, and a control program for the vehicle seat. [Means for solving the problem]

[0006] In order to solve the above problem, one aspect of the present invention is a vehicle seat (1) comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, and when the heart rate is greater than a predetermined upper threshold (n2), the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0007] According to this aspect, when the heart rate is higher than the upper threshold, vibrations with a frequency corresponding to the heart rate are transmitted to the driver, thereby relieving the driver of tension. Thus, a vehicle seat can be provided that can guide the driver into a state suitable for driving operations.

[0008] In the above aspect, preferably, the control device sets, in the induction control, the frequency of the vibration output by the vibration device so as to be directly proportional to the heart rate.

[0009] According to this aspect, when the heart rate is higher than the upper threshold and the driver is considered to be excited, the frequency of the vibration to be output by the vibration device is set to be directly proportional to the heart rate, thereby providing appropriate guidance to the driver.

[0010] In the above aspect, preferably, the control device reduces the frequency of the vibration output by the vibration device over time during the induction control.

[0011] According to this aspect, the driver's excitement can be alleviated.

[0012] In the above aspect, preferably, when the heart rate is equal to or lower than a lower threshold (n1) that is smaller than the upper threshold, the control device executes awakening control to vibrate the vibration device to awaken the driver.

[0013] According to this aspect, when the heart rate is equal to or lower than the lower threshold, it is possible to encourage the driver to wake up.

[0014] In the above aspect, preferably, the control device sets the frequency of the vibration output by the vibration device to a constant value during the wakefulness control.

[0015] According to this aspect, when the heart rate is equal to or lower than the lower threshold and the driver is considered not to be awake, it is possible to easily determine the frequency of vibration to be output by the vibration device.

[0016] In the above aspect, preferably, the control device acquires the elapsed time since the driver started operating the vehicle, and when the elapsed time is less than a predetermined time threshold, prohibits activation of the vibration device.

[0017] According to this aspect, when the time that has elapsed since the start of driving is short and it is considered that at least the guidance control is unnecessary, these controls can be stopped.

[0018] In the above aspect, preferably, the control device acquires information regarding whether or not the driver smokes, and when it determines that the driver smokes, it sets the upper threshold higher than when the driver does not smoke.

[0019] According to this aspect, the upper threshold can be set taking into consideration an increase in heart rate due to smoking.

[0020] In the above aspect, preferably, the seat body is provided with a seating sensor (57) that acquires information related to the seating area of ​​the driver, and in the wakefulness control, when the seating area acquired by the seating sensor is equal to or greater than a predetermined area threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger than when the seating area is less than the area threshold.

[0021] According to this aspect, the amplitude can be appropriately set in consideration of the physique of the driver.

[0022] In the above aspect, preferably, the control device is connected to an outdoor temperature sensor (19) that acquires the outdoor temperature, which is the temperature outside the passenger compartment, and when the outdoor temperature is below a predetermined temperature threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger in the awakening control than when the outdoor temperature is equal to or greater than the temperature threshold.

[0023] According to this aspect, when it is predicted that the driver is wearing multiple layers of clothing, the amplitude can be set so that the vibration is transmitted to the driver.

[0024] In the above aspect, preferably, the control device is connected to an outdoor temperature sensor (19) that acquires an outdoor temperature, which is the temperature outside the passenger compartment, and an indoor temperature sensor (20) that acquires an indoor temperature, which is the temperature inside the passenger compartment, and when the outdoor temperature is less than a predetermined first temperature threshold and the indoor temperature is less than a predetermined second temperature threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger in the awakening control compared to when the outdoor temperature is equal to or greater than the first temperature threshold and the indoor temperature is equal to or greater than the second temperature threshold.

[0025] According to this aspect, when it is predicted that the driver is wearing multiple layers of clothing, the amplitude can be set so that the vibration is transmitted to the driver.

[0026] In order to solve the above problem, one aspect of the present invention is a vehicle seat (1) comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, wherein the control device sets the frequency of vibrations generated by the vibration device to asymptotically approach a function proportional to the heart rate as the heart rate increases and approaches an upper threshold value (n2).

[0027] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a vehicle seat can be provided that can guide the driver into a state suitable for driving operations.

[0028] In the above aspect, preferably, the control device sets the frequency of vibration generated by the vibration device to gradually approach a constant output value when the heart rate decreases and approaches a lower threshold value which is smaller than the upper threshold value.

[0029] According to this aspect, it is possible to simply set the frequency of the vibration to be applied when the heart rate approaches the lower threshold value and the driver is to be alerted.

[0030] In order to solve the above problem, one aspect of the present invention is a seat system (1) including a vehicle seat having a seat body (41) on which a driver sits and a vibration device (42) provided on the seat body, a heart rate sensor (35) that acquires the driver's heart rate, and a control device (43) that controls the driving of the vibration device, wherein when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0031] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations.

[0032] In order to solve the above problem, one aspect of the present invention is a control method for a vehicle seat comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, wherein when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0033] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations.

[0034] In order to solve the above problem, one aspect of the present invention is a control program for a vehicle seat that includes a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, and when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0035] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations. [Effects of the Invention]

[0036] In order to solve the above problem, one aspect of the present invention is a vehicle seat (1) comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, and when the heart rate is greater than a predetermined upper threshold (n2), the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0037] According to this aspect, when the heart rate is higher than the upper threshold, vibrations with a frequency corresponding to the heart rate are transmitted to the driver, thereby relieving the driver of tension. Thus, a vehicle seat can be provided that can guide the driver into a state suitable for driving operations.

[0038] In the above aspect, preferably, the control device sets, in the induction control, the frequency of the vibration output by the vibration device so as to be directly proportional to the heart rate.

[0039] According to this aspect, when the heart rate is higher than the upper threshold and the driver is considered to be excited, the frequency of the vibration to be output by the vibration device is set to be directly proportional to the heart rate, thereby providing appropriate guidance to the driver.

[0040] In the above aspect, preferably, the control device reduces the frequency of the vibration output by the vibration device over time during the induction control.

[0041] According to this aspect, the driver's excitement can be alleviated.

[0042] In the above aspect, preferably, when the heart rate is equal to or lower than a lower threshold (n1) that is smaller than the upper threshold, the control device executes awakening control to vibrate the vibration device to awaken the driver.

[0043] According to this aspect, when the heart rate is equal to or lower than the lower threshold, it is possible to encourage the driver to wake up.

[0044] In the above aspect, preferably, the control device sets the frequency of the vibration output by the vibration device to a constant value during the wakefulness control.

[0045] According to this aspect, when the heart rate is equal to or lower than the lower threshold and the driver is considered not to be awake, it is possible to easily determine the frequency of vibration to be output by the vibration device.

[0046] In the above aspect, preferably, the control device acquires the elapsed time since the driver started operating the vehicle, and when the elapsed time is less than a predetermined time threshold, prohibits activation of the vibration device.

[0047] According to this aspect, when the time that has elapsed since the start of driving is short and it is considered that at least the guidance control is unnecessary, these controls can be stopped.

[0048] In the above aspect, preferably, the control device acquires information regarding whether or not the driver smokes, and when it determines that the driver smokes, it sets the upper threshold higher than when the driver does not smoke.

[0049] According to this aspect, the upper threshold can be set taking into consideration an increase in heart rate due to smoking.

[0050] In the above aspect, preferably, the seat body is provided with a seating sensor (57) that acquires information related to the seating area of ​​the driver, and in the wakefulness control, when the seating area acquired by the seating sensor is equal to or greater than a predetermined area threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger than when the seating area is less than the area threshold.

[0051] According to this aspect, the amplitude can be appropriately set in consideration of the physique of the driver.

[0052] In the above aspect, preferably, the control device is connected to an outdoor temperature sensor (19) that acquires the outdoor temperature, which is the temperature outside the passenger compartment, and when the outdoor temperature is below a predetermined temperature threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger in the awakening control than when the outdoor temperature is equal to or greater than the temperature threshold.

[0053] According to this aspect, when it is predicted that the driver is wearing multiple layers of clothing, the amplitude can be set so that the vibration is transmitted to the driver.

[0054] In the above aspect, preferably, the control device is connected to an outdoor temperature sensor (19) that acquires an outdoor temperature, which is the temperature outside the passenger compartment, and an indoor temperature sensor (20) that acquires an indoor temperature, which is the temperature inside the passenger compartment, and when the outdoor temperature is less than a predetermined first temperature threshold and the indoor temperature is less than a predetermined second temperature threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger in the awakening control compared to when the outdoor temperature is equal to or greater than the first temperature threshold and the indoor temperature is equal to or greater than the second temperature threshold.

[0055] According to this aspect, when it is predicted that the driver is wearing multiple layers of clothing, the amplitude can be set so that the vibration is transmitted to the driver.

[0056] In order to solve the above problem, one aspect of the present invention is a vehicle seat (1) comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, wherein the control device sets the frequency of vibrations generated by the vibration device to asymptotically approach a function proportional to the heart rate as the heart rate increases and approaches an upper threshold value (n2).

[0057] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a vehicle seat can be provided that can guide the driver into a state suitable for driving operations.

[0058] In the above aspect, preferably, the control device sets the frequency of vibration generated by the vibration device to gradually approach a constant output value when the heart rate decreases and approaches a lower threshold value which is smaller than the upper threshold value.

[0059] According to this aspect, it is possible to simply set the frequency of the vibration to be applied when the heart rate approaches the lower threshold value and the driver is to be alerted.

[0060] In order to solve the above problem, one aspect of the present invention is a seat system (1) including a vehicle seat having a seat body (41) on which a driver sits and a vibration device (42) provided on the seat body, a heart rate sensor (35) that acquires the driver's heart rate, and a control device (43) that controls the driving of the vibration device, wherein when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0061] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations.

[0062] In order to solve the above problem, one aspect of the present invention is a control method for a vehicle seat comprising a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, wherein when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0063] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations.

[0064] In order to solve the above problem, one aspect of the present invention is a control program for a vehicle seat that includes a seat body (41) on which a driver sits, a vibration device (42) provided on the seat body, and a control device (43) that acquires the driver's heart rate and controls the driving of the vibration device, and when the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

[0065] According to this aspect, when the heart rate approaches the upper threshold, vibrations having a frequency proportional to the heart rate are transmitted to the driver, thereby relieving the driver's tension. Thus, a seat system can be provided that can guide the driver into a state suitable for driving operations. [Brief explanation of the drawings]

[0066] [Figure 1] FIG. 1A is a side view showing the interior of a vehicle equipped with a vehicle seat according to a first embodiment; FIG. 1B is an enlarged cross-sectional view of a portion surrounded by a dashed line; and FIG. 1C is an enlarged cross-sectional view of a portion surrounded by a dashed line. [Figure 2] Block diagram of a seat system according to a first embodiment [Figure 3] Flowchart of seat control processing according to the first embodiment [Figure 4] Table showing an example of setting the amplitude based on the temperature outside and inside the vehicle [Figure 5] Graphs showing the heart rate dependence of (A) the amplitude and (B) the frequency of vibration output from the vibration device in the first embodiment. [Figure 6] 1 is a table showing an example of the detection result of the heart rate sensor when wakefulness control and induction control are performed, and an example of the waveform of the output vibration output from the vibration device. [Figure 7] Example of instrument panel display during guidance control [Figure 8] Flowchart of seat control processing according to the second embodiment [Figure 9] Graphs showing the heart rate dependency of (A) output amplitude and (B) output frequency set in the second embodiment. [Figure 10] Graphs showing the heart rate dependence of (A) the amplitude and (B) the frequency of vibration output from a vibration device in a third embodiment. [Figure 11] 10 is a graph showing the heart rate dependency of (A) the amplitude and (B) the frequency of vibration output from a vibration device in a modified example of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0067] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, with reference to the drawings, embodiments of a vehicle seat, a seat system, a control method for a vehicle seat, and a control program for a vehicle seat according to the present invention will be described.

[0068] As shown in Fig. 1(A), a seat system 1 is mounted on a vehicle 2 such as an automobile. For convenience of explanation, the following description will be based on the vehicle 2 to define front / rear, left / right, and up / down directions.

[0069] A vehicle control device 4 is provided on a vehicle body 3. As shown in Fig. 2, the vehicle control device 4 is configured by an electronic control unit (ECU) including a processor 5 such as a CPU, a non-volatile memory 6 (ROM), a volatile memory 7 (RAM), a storage 8, a communication interface 9 (communication I / F), and the like.

[0070] The vehicle control device 4 is capable of executing driving modes including an automatic driving mode and a manual driving mode. In the automatic driving mode, the vehicle control device 4 controls the drive source, braking device, and steering device of the vehicle 2 based on signals from various sensors to automatically drive the vehicle 2. In the manual driving mode, the vehicle control device 4 controls the drive source, braking device, and steering device of the vehicle 2 based on the driver's driving operations on the steering wheel, accelerator pedal, and brake pedal to manually drive the vehicle 2.

[0071] The vehicle control device 4 switches the driving mode of the vehicle 2 between an autonomous driving mode and a manual driving mode. For example, when the vehicle 2 approaches an end point of the autonomous driving, the vehicle control device 4 switches the driving mode from the autonomous driving mode to the manual driving mode. The end point of the autonomous driving can be set, for example, at an exit of a highway.

[0072] The vehicle control device 4 stores the time that the vehicle 2 has been manually driven since it was started as the elapsed time. When the vehicle 2 is stopped (shut down), the vehicle control device 4 resets the elapsed time to zero. When the vehicle control device 4 receives a request from an external device, it transmits the elapsed time to the external device.

[0073] As shown in FIG. 1(A), a vehicle 2 is provided with a passenger compartment 10, and a driver's seat 11 where a driver sits is provided within the passenger compartment 10. An instrument panel 12 is disposed in front of the driver's seat 11. The instrument panel 12 is provided with a display device 13 that displays information on a screen and notifies the driver of various pieces of information. In this embodiment, the display device 13 is configured as a liquid crystal display. The vehicle control device 4 is connected to the display device 13 and controls the screen display of the display device 13.

[0074] A door 15 is provided on the side of the driver's seat 11. A door trim 16 is connected to the side of the door 15 on the inside of the vehicle. A speaker 17 is provided on the door trim 16 to output audio and notify the driver of various information. The vehicle control device 4 is connected to the speaker 17 and controls the audio output of the speaker 17.

[0075] A driver camera 18 for capturing an image of the driver may be provided inside the vehicle compartment 10 (in front of the driver's seat 11 in this embodiment). The driver camera 18 is connected to the vehicle control device 4 and transmits captured images of the driver to the vehicle control device 4 in real time. The vehicle control device 4 may determine whether or not the driver is smoking based on the captured images using known image analysis technology. When the vehicle control device 4 receives a request from an external device, it may transmit the determination result regarding whether or not the driver is smoking to the external device that made the request.

[0076] The vehicle 2 may be provided with an interior temperature sensor 19 and an exterior temperature sensor 20. The interior temperature sensor 19 is a known interior temperature sensor that detects the temperature inside the vehicle compartment 10 (hereinafter referred to as the interior temperature). The exterior temperature sensor 20 is a known exterior temperature sensor that detects the temperature outside the vehicle (hereinafter referred to as the exterior temperature). The interior temperature sensor 19 and the exterior temperature sensor 20 are preferably connected to the vehicle control device 4 and output the detected interior and exterior temperatures to the vehicle control device 4. When the vehicle control device 4 receives a request from an external device, the vehicle control device 4 may transmit the interior temperature acquired by the interior temperature sensor 19 and the exterior temperature acquired by the exterior temperature sensor 20 to the external device that made the request in response to the request. In this way, the external device can connect to the interior temperature sensor 19 and the exterior temperature sensor 20 via the vehicle control device 4 and acquire the interior and exterior temperatures.

[0077] As shown in FIG. 2, the seat system 1 includes a wearable terminal 25 and a vehicle seat 26.

[0078] 1A, the wearable terminal 25 is a terminal worn by the driver, and in this embodiment, is a smart watch (wristwatch-type terminal) worn on the wrist of the driver. As shown in FIG. 2, the wearable terminal 25 includes a processor 31, a memory 32, a communication interface 33 (communication I / F), a touch panel 34, and a heart rate sensor 35.

[0079] The heart rate sensor 35 acquires information related to the driver's heart rate. The heart rate sensor 35 may be an optical heart rate sensor equipped with a light-emitting element that irradiates light toward the driver's skin and a photodiode that detects the intensity of the reflected light. The waveform detected by the heart rate sensor 35 indicates the intensity of the reflected light detected by the photodiode, and reflects changes in blood flow due to the heartbeat. Alternatively, the heart rate sensor 35 may be a sensor that uses the Doppler effect using radio waves, or may be a sensor that uses a piezoelectric element.

[0080] The processor 31 of the wearable device 25 acquires the heart rate by performing time series analysis on the waveform acquired by the heart rate sensor 35. The processor 31 may acquire the heart rate, for example, by acquiring the time interval from one peak to the next peak in the waveform output from the heart rate sensor 35. The processor 31 of the wearable device 25 can transmit the acquired heart rate in real time to an external device via the communication interface 33.

[0081] When the driver becomes tense or excited, the driver's heart rate increases. On the other hand, when the driver's level of alertness decreases, the driver's heart rate decreases. To determine the driver's state, the memory 32 of the wearable device 25 stores a lower limit value (hereinafter referred to as the lower heart rate limit value) and an upper limit value (hereinafter referred to as the upper heart rate limit value) of the heart rate suitable for driving operations.

[0082] The lower heart rate limit is set as a heart rate threshold at which the driver's level of alertness is too low, which may cause delays in driving operations or a decline in the driver's judgment or cognitive ability, whereas the upper heart rate limit is set as a heart rate threshold at which the driver is too excited, which may cause delays in driving operations or a decline in the driver's judgment or cognitive ability.

[0083] When the wearable device 25 is always attached to the driver, the processor 31 may estimate the lower and upper heart rate limits based on the standard heart rate acquired by the heart rate sensor 35 and record the estimate in the memory 32. Alternatively, the lower and upper heart rate limits may be set by the processor 31 based on the driver's age, blood pressure, physique, etc. input via the touch panel 34 and recorded in the memory 32. In this case, the lower and upper heart rate limits are set to values ​​specific to each driver, allowing for a more appropriate assessment of the driver's condition.

[0084] Alternatively, the lower and upper heart rate limits may be set based on standard values ​​for a healthy person and stored in the memory 32 at the time of factory shipment or when various applications are installed. Also, the processor 31 may communicate with various servers via the communication interface 33 to acquire the lower and upper heart rate limits and record them in the memory 32.

[0085] As shown in FIG. 1(A), the vehicle seat 26 includes a seat body 41, a vibration device 42, and a seat control device 43.

[0086] The seat body 41 constitutes the driver's seat 11. The seat body 41 has a seat cushion 46 provided on a floor 45 that defines the bottom of the vehicle interior 10, a seat back 47 extending upward from the rear of the seat cushion 46, and a headrest 48 connected to an upper part of the seat back 47.

[0087] The seat cushion 46 supports the buttocks of the driver. The seat back 47 is disposed behind the driver and functions as a backrest. The headrest 48 is disposed behind the driver's head. The seat back 47 is rotatably connected to the seat cushion 46 via a reclining device (not shown) and is supported so as to be able to tilt relative to the seat cushion 46.

[0088] The seat cushion 46 includes a frame (not shown) that forms the framework, a pad 51 supported by the frame, and a cover material 52 that covers the upper surface of the pad 51. The pad 51 is made of a cushioning material such as urethane. The cover material 52 is made of a sheet-like material such as cloth or leather.

[0089] The seat back 47 includes a frame (not shown) that forms the framework, a pad 51 supported by the frame, and a cover material 54 that covers the front of the pad 53. The pad 53 is made of a cushioning material such as urethane. The cover material 54 is made of a sheet-like material such as cloth or leather.

[0090] The frame that constitutes the seat back 47 is connected at its lower end to the rear part of the frame that constitutes the seat cushion 46 so as to be rotatable about an axis that extends in the left-right direction.

[0091] The seat body 41 may be supported on the floor 45 via a rotation device so as to be rotatable about an axis extending in the up-down direction on the floor 45. The seat body 41 may also be supported on the floor 45 via a slide device so as to be movable back and forth.

[0092] The seat main body 41 may be provided with a seating sensor 57 that acquires information related to the physique of the driver. The seating sensor 57 may include a sheet-shaped detection unit 57A. The detection unit 57A may acquire the pressure distribution applied by the driver. The detection unit 57A may be provided between the upper surface of the pad 51 of the seat cushion 46 and the lower surface of the upholstery material 52 of the seat cushion 46. The detection unit 57A may be provided between the front surface of the pad 53 of the seat back 47 and the rear surface of the upholstery material 54 of the seat back 47. The seating sensor 57 may acquire the area of ​​a region where pressure equal to or greater than a predetermined threshold is detected as the seating area of ​​the driver based on the pressure distribution detected by the detection unit 57A.

[0093] The seating sensor 57 is preferably connected to the seat control device 43 via a harness (not shown) and outputs the acquired seating area to the seat control device 43.

[0094] The vibration device 42 (also referred to as a vibration device) includes one or more vibrators 59 that generate vibrations. In this embodiment, the vibration device 42 includes a plurality of vibrators 59 (hereinafter referred to as back-side vibrators 59A) provided on the seat back 47 and a plurality of vibrators 59 (hereinafter referred to as cushion-side vibrators 59B) provided on the seat cushion 46.

[0095] 1(B), the back-side vibrator 59A is preferably disposed inside a recess 53A formed in the front surface of a pad 53 constituting the seat back 47. The back-side vibrator 59A is preferably covered from the front by a covering material 54 that covers the front surface of the pad 53 of the seat back 47. The vibrations output by the back-side vibrator 59A are transmitted to the driver via the pad 53 of the seat back 47 and the covering material 54.

[0096] 1(C), the cushion-side vibrator 59B is preferably disposed inside a recess 51A formed on the upper surface of a pad 51 constituting the seat cushion 46. The cushion-side vibrator 59B is preferably covered from above by a covering material 52 that covers the upper surface of the pad 51 of the seat cushion 46. The vibration output by the back-side vibrator 59A is transmitted to the driver via the pad 51 of the seat cushion 46 and the covering material 52.

[0097] At least one of the vibrators 59 is configured by an alternating current motor (AC motor), and the amplitude and frequency of the output vibration are changed independently depending on the amplitude and frequency of the input AC voltage. Hereinafter, such a vibrator 59 that can change the amplitude and frequency will be referred to as an independently variable vibrator 59C. The AC motor that configures the independently variable vibrator 59C may be a known motor such as a linear vibration motor or a piezoelectric vibration motor.

[0098] In this embodiment, all of the vibrators 59 included in the vibration device 42 are configured as independent variable vibrators 59C. However, this is not limited to this embodiment, and some of the vibrators 59 of the vibration device 42 may be configured as direct current motors (DC motors), and the frequency and amplitude of the output vibration may be changed in conjunction with each other depending on the magnitude of the applied voltage. Hereinafter, such vibrators 59, the amplitude and frequency of which are changed in conjunction with each other, will be referred to as interlocking fixed vibrators 59D.

[0099] When the vibration device 42 includes the independent variable vibrator 59C and the interlocking fixed vibrator 59D, it is preferable that at least one independent variable vibrator 59C is provided in the center in the vertical direction and in the center in the horizontal direction of the seat back 47. This makes it possible to arrange the at least one independent variable vibrator 59C in a position where the driver can easily recognize the vibration.

[0100] As shown in FIG. 2, the seat control device 43 is composed of an electronic control unit (ECU) including a processor 61 such as a CPU, a non-volatile memory 62 (ROM), a volatile memory 63 (RAM), a storage 64, a communication interface 65 (communication I / F), and a digital-to-analog converter 66 (DA converter).

[0101] The processor 61 of the seat control device 43 is configured to be able to communicate with the vehicle control device 4 via the communication interface 65. The processor 61 of the seat control device 43 sends a request to the vehicle control device 4 via the communication interface 65 and acquires the elapsed time.

[0102] The processor 61 of the seat control device 43 is configured to be able to communicate with the wearable terminal 25 via the communication interface 65. The processor 61 of the seat control device 43 communicates with the wearable terminal 25 and acquires the driver's heart rate from the wearable terminal 25 in real time.

[0103] The seat control device 43 is connected to each of the vibrators 59 via a harness 71. In this embodiment, the seat control device 43 is coupled to the bottom surface of the seat cushion 46. As shown in FIGS. 1(B) and 1(C), a harness passage 72 is formed in each of the pad 51 of the seat cushion 46 and the pad 53 of the seat back 47. In the pad 51 of the seat cushion 46, the harness passage 72 extends from its underside to the recess 51A, and in the pad 53 of the seat back 47, the harness passage 72 extends from its rear surface to the recess 51A. The seat control device 43 and each of the vibrators 59 are connected by the harness 71 passing through the harness passage 72.

[0104] The digital-to-analog converter 66 (DA converter) converts the digital signal output from the processor 61 of the seat control device 43 into an analog voltage and outputs it to the corresponding vibrator 59. This makes it possible for the amplitude and frequency of the vibration output from each vibrator 59 to be controlled by the seat control device 43. In detail, the seat control device 43 can independently control the amplitude and frequency of the vibration output from the independent variable vibrator 59C, and can control the amplitude or frequency of the vibration output from the interlocked fixed vibrator 59D.

[0105] The processor 61 of the seat control device 43 executes a control program stored in the non-volatile memory 62 or the storage 64 to perform a control process (hereinafter referred to as the seat control process) for the vehicle seat 26 that controls the drive of the vibration device 42 (more specifically, the independent variable vibrator 59C) based on the heart rate and elapsed time, thereby implementing a control method for the vehicle seat 26.

[0106] Next, details of the seat control process executed by the processor 61 of the seat control device 43 will be described with reference to a flowchart. The processor 61 repeatedly executes the seat control process while the vehicle 2 is running.

[0107] Two embodiments of the seat control process executed by the seat control device 43 will be described below.

[0108] <<First Embodiment>> 3, in the first step ST1 of the seat control process according to the first embodiment, the processor 61 of the seat control device 43 acquires the elapsed time from the vehicle control device 4 and determines whether the elapsed time is equal to or greater than a predetermined time threshold. If the elapsed time is equal to or greater than the time threshold, the processor 61 executes step ST2, and if the elapsed time is less than the time threshold, the processor 61 ends the seat control process.

[0109] In step ST2, the processor 61 executes a threshold setting process to set a first threshold n1 (also referred to as a lower threshold) and a second threshold n2.

[0110] In the threshold setting process, the processor 61 acquires the lower and upper heart rate limits from the wearable device 25, sets the lower heart rate limit to the first threshold n1, and sets the upper heart rate limit to the second threshold n2.

[0111] In another embodiment, in the threshold setting process, the processor 61 acquires the lower heart rate limit value and the upper heart rate limit value from the wearable device 25, and acquires the determination result regarding whether the driver smokes from the vehicle control device 4. Thereafter, if it is determined that the driver does not smoke, the processor 61 sets the lower heart rate limit value to the first threshold n1 and the upper heart rate limit value to the second threshold n2. If it is determined that the driver smokes, the processor 61 sets the lower heart rate limit value to the first threshold n1 and sets the second threshold n2 to a predetermined value greater than the upper heart rate limit value. If it is determined that the driver smokes, the processor 61 may set the second threshold n2 to a value obtained by multiplying the upper heart rate limit value by a predetermined constant of 1 or more, or may set the second threshold n2 to a value obtained by adding a predetermined positive value to the upper heart rate limit value.

[0112] When the setting of the first threshold value n1 and the second threshold value n2 is completed, the processor 61 executes step ST3.

[0113] In step ST3, processor 61 acquires the heart rate from wearable device 25 based on the detection result of heart rate sensor 35, and determines whether the acquired heart rate is equal to or less than first threshold value n1. If the heart rate is equal to or less than first threshold value n1, processor 61 executes step ST4, and if the heart rate is greater than first threshold value n1, processor 61 executes step ST5.

[0114] In step ST4, the processor 61 performs wakefulness control. The wakefulness control is control of the vibration device 42, and is performed to wake up the driver.

[0115] In wakefulness control, processor 61 generates a digital signal for causing each vibrator 59 to output a vibration having a first amplitude A1 and a first frequency f1, and outputs the signal to digital-to-analog converter 66. Note that first amplitude A1 and first frequency f1 are each constants that are independent of the heart rate. Digital-to-analog converter 66 generates an AC voltage corresponding to the input digital signal, and inputs the AC voltage to each vibrator 59.

[0116] The processor 61 outputs a digital signal for causing each of the vibrators 59 to output vibrations having a first amplitude A1 and a first frequency f1 for a predetermined period of time, and then ends the seat control process.

[0117] In the wakefulness control, the processor 61 may acquire the seating area from the seating sensor 57. In this case, the processor 61 may set the digital signal so that when the seating area is equal to or greater than a predetermined area threshold, the amplitude of the vibration output from each vibrator 59 is larger than when the seating area is less than the area threshold. This allows the amplitude to be set appropriately taking into account the physique of the driver.

[0118] In the wakefulness control, the processor 61 may acquire the outside temperature from the vehicle control device 4. In this case, the processor 61 may set the digital signal so that when the outside temperature is below a predetermined temperature threshold, the amplitude of the vibration output from each vibrator 59 is larger than when the outside temperature is equal to or higher than the temperature threshold. This allows the amplitude to be set so that the vibration is transmitted to the driver when it is predicted that the driver is wearing multiple layers of clothing.

[0119] Additionally, in the awakening control, the processor 61 may acquire the outside temperature and the inside temperature from the vehicle control device 4. When the outside temperature is below a predetermined first temperature threshold and the inside temperature is below a predetermined second temperature threshold, the processor 61 may set the digital signal so that the amplitude of the vibration output from each vibrator 59 is larger than when the outside temperature is equal to or greater than the first temperature threshold and the inside temperature is equal to or greater than the second temperature threshold. Even in this case, the amplitude can be set so that the vibration is transmitted to the driver when it is predicted that the driver is wearing multiple layers of clothing.

[0120] 4 shows a table indicating the amplitude of vibration set by the processor 61 at this time. The processor 61 sets the digital signal so that the amplitude is B1 when the outside-vehicle temperature is less than the first temperature threshold and the inside-vehicle temperature is less than the second temperature threshold. The processor 61 sets the digital signal so that the amplitude is B2 when the outside-vehicle temperature is equal to or greater than the first temperature threshold and the inside-vehicle temperature is less than the second temperature threshold. The processor 61 also sets the digital signal so that the amplitude is B2 when the outside-vehicle temperature is less than the first temperature threshold and the inside-vehicle temperature is equal to or greater than the second temperature threshold. The processor 61 sets the digital signal so that the amplitude is B3 when the outside-vehicle temperature is equal to or greater than the first temperature threshold and the inside-vehicle temperature is equal to or greater than the second temperature threshold. Note that B1 is set to a value greater than B2, and B2 is set to a value greater than B3 (B1>B2>B3).

[0121] In step ST5, the processor 61 determines whether the heart rate acquired in step ST3 is greater than the second threshold n2. As shown in Fig. 3, if the heart rate acquired in step ST3 is greater than the second threshold n2, the processor 61 executes step ST6. If the heart rate acquired in step ST3 is equal to or less than the second threshold n2, the processor 61 ends the seat control process.

[0122] The processor 61 performs guidance control in step ST6. The guidance control is control of the vibration device 42, and is performed to relieve the driver's tension and excitement.

[0123] In step ST6, the processor 61 generates a digital signal for causing each of the vibrators 59 to output a vibration having a second amplitude A2 and a second frequency f2, and outputs the signal to the digital-to-analog converter 66. The second amplitude A2 is a constant independent of the heart rate, and the second frequency f2 is directly proportional to the heart rate n (i.e., f2=kn, where k is a proportionality constant). The digital-to-analog converter 66 generates an AC voltage corresponding to the input digital signal and inputs it to each of the vibrators 59. The second amplitude A2 is preferably smaller than the first amplitude A1. Alternatively, the proportionality constant k may be set to 1, and the second frequency f2 may be configured to be equal to the heart rate n.

[0124] The proportionality constant k is not limited to 1, and may be any positive constant, such as 0.5 or 2. For example, by setting the proportionality constant k to a value greater than 1, the second frequency f2 can be set to a value slightly greater than the heart rate in the guidance control.

[0125] The processor 61 may also obtain the second frequency f2 by substituting the heart rate n into a linear function f(x), which may be expressed as f(x) = kx + x0 (where k and x0 are both positive constants).

[0126] Alternatively, in the induction control, the processor 61 may set the second frequency f2 to be directly proportional to the heart rate n, and then generate a digital signal to gradually decrease the second frequency f2 over time, in order to relieve the driver's tension.

[0127] The processor 61 outputs digital signals to each of the vibrators 59 for a predetermined time to cause the vibrators 59 to output vibrations with the second amplitude A2 and the second frequency f2, and then ends the seat control process.

[0128] Next, the effects of the vehicle seat 26 configured as above, the seat system 1, the control method for the vehicle seat 26, and the control program for the vehicle seat 26 will be described.

[0129] If the driver's level of alertness is too low, there is a risk of delays in driving operations, or of the driver's judgment and cognitive abilities being impaired. If the driver is too excited, there is a risk of delays in driving operations, or of the driver's judgment and cognitive abilities being impaired. The heart rate decreases when the driver's level of alertness is low, and increases when the driver is excited.

[0130] FIG. 5(A) shows the heart rate dependency of the amplitude of the vibration generated by the vibration device 42, and FIG. 5(B) shows the heart rate dependency of the frequency of the vibration generated by the vibration device 42.

[0131] When the heart rate obtained from the detection result of the heart rate sensor 35 is equal to or lower than the first threshold value n1 (Yes in ST3), awakening control is performed (ST4), and vibration is generated from the vibration device 42, as shown in Fig. 7. This can encourage the driver to wake up.

[0132] When the heart rate obtained from the detection result of the heart rate sensor 35 is greater than the second threshold n2 (Yes in ST5), guidance control is performed (ST6). In guidance control, as shown in Fig. 7, vibrations with a frequency corresponding to the heart rate are generated from the vibration device 42. This provides a biofeedback effect in which vibrations corresponding to the heart rate are transmitted to the driver, encouraging the driver to make self-regulation such as relaxing tension.

[0133] In addition, in the induction control, when the second frequency f2 of the vibration output gradually decreases over time, the so-called synchronization phenomenon between the vibration rhythm and the heartbeat can calm the driver and reduce the driver's excitement.

[0134] Alternatively, in the guidance control, the processor 61 may set the proportionality constant k to a value smaller than 1 and control the frequency of the vibration generated by the vibration device 42 to be smaller than the driver's heart rate. This may result in the driver's heart rate being induced to approach that frequency in the guidance control, thereby decreasing the driver's heart rate. In this case, as the driver's heart rate decreases, the frequency of the vibration generated by the vibration device 42 also decreases further, gradually decreasing the driver's heart rate and reducing tension and excitement in the driver.

[0135] In this way, it is possible to provide a vehicle seat 26, a seat system 1 including the vehicle seat 26, a control method for the vehicle seat 26, and a control program for the vehicle seat 26, which can encourage the driver to become awake when the driver's level of alertness is low and encourage the driver to relax when the driver is excited, thereby guiding the driver into a state suitable for driving operations.

[0136] Furthermore, when the elapsed time is less than the threshold value (No in ST1), processor 61 ends the seat control process. Therefore, when the elapsed time from the start of driving is short and it is considered that the awakening control and the guidance control are unnecessary, the awakening control and the guidance control can be stopped and the driving of vibration device 42 can be prohibited.

[0137] In the above embodiment, the output is stopped when the output for a predetermined time is completed in the awakening control and induction control, but the processor 61 may continue to output the digital signal even after the predetermined time has elapsed so that vibrations are output at the amplitude and frequency set in the awakening control and induction control.

[0138] Furthermore, in the guidance control, the processor 61 may send a request to the vehicle control device 4 to have the speaker 17 output a sound corresponding to the driver's heart rate. The sound output from the speaker may increase in volume in accordance with the rhythm of the heart rate. The sound output from the speaker may also be slightly faster (or slightly slower) than the rhythm of the heart rate and may increase in volume. This allows the driver to be notified of their heart rate by voice, which can calm the driver down through a biofeedback effect.

[0139] Additionally, during guidance control, the processor 61 may send a request to the vehicle control device 4 to have the display device 13 display a screen related to the driver's heart rate. In this case, the driver is notified of their heart rate via a screen display, which can calm the driver down through a biofeedback effect. FIG. 7 shows an example of a screen that displays the heart rate on the display device 13 of the instrument panel 12. In FIG. 7, the size of an icon 80 displayed on the screen may be changed at a cycle corresponding to the heart rate (specifically, at a cycle that is the inverse of the heart rate, or at a cycle that is longer (or shorter) than the inverse of the heart rate).

[0140] <<Second embodiment>> 8, the seat control process according to the second embodiment differs from the seat control process according to the first embodiment in the processes other than steps ST1 and ST2. Therefore, a description of steps ST1 and ST2 will be omitted here.

[0141] As shown in FIG. 8, when the processor 61 completes the threshold setting process in step ST2, it executes the output amplitude determination process in step ST11.

[0142] In the output amplitude determination process, the processor 61 determines the output amplitude corresponding to the heart rate acquired in step ST2 using the graph showing the relationship between the heart rate and the output amplitude shown in FIG. 9(A).

[0143] 9(A), when the acquired heart rate is sufficiently smaller than the first threshold n1, the output amplitude is set to a constant first amplitude A1. As the heart rate increases toward the first threshold n1, the set output amplitude gradually decreases, and when the heart rate exceeds the first threshold n1, the set output amplitude becomes zero. Thereafter, as the heart rate increases toward the second threshold n2, the set output amplitude gradually increases, and when the heart rate exceeds the second threshold n2, the set output amplitude is set to a constant second amplitude A2.

[0144] The curve showing the relationship between heart rate and output amplitude shown in Figure 9(A) is composed of a combined (connected) curve of a sigmoid curve having an inflection point at the first threshold value n1 and a sigmoid curve having an inflection point at the second threshold value n2.

[0145] In the output amplitude determination process, the processor 61 may determine the output amplitude A(n) corresponding to the heart rate n acquired in step ST2 using the following equation (1).

[0146]

number

[0147] In equation (1), A1 and A2 are the first amplitude and the second amplitude, respectively, and ζ1(x) and ζ2(x) are both sigmoid functions, and are expressed by the following equation (2).

[0148]

number

[0149] Here, a1 and a2 are positive constants also called gains.

[0150] The processor 61 may determine the output amplitude A(n) by substituting the heart rate n obtained in step ST2 into equation (1).

[0151] When the determination of the output amplitude is completed, the processor 61 executes the output frequency determination process of step ST12 as shown in FIG.

[0152] In the output frequency determination process, the processor 61 determines the output amplitude corresponding to the heart rate acquired in step ST2 using the graph showing the relationship between the heart rate and the output frequency shown in FIG. 9(B).

[0153] As shown in FIG. 9(B), when the acquired heart rate is sufficiently smaller than the first threshold n1, the output frequency is set to a first frequency f1, which is a constant output value (i.e., a constant). As the heart rate increases toward the first threshold n1, the set output frequency gradually decreases, and when it exceeds the first threshold n1, the set output frequency becomes zero. Thereafter, as the heart rate increases toward the second threshold n2, the set output frequency gradually increases and gradually approaches a second frequency f2, which is a constant output value (i.e., a constant). As in the first embodiment, the second frequency f2 is proportional to the acquired heart rate n (f2=kn, where k is a proportionality constant).

[0154] As shown in Figure 9(B), the output frequency is set to gradually increase from zero when the acquired heart rate decreases and approaches the first threshold value n1, and to asymptotically approach the first frequency f1, which is a constant output value (i.e., a constant).

[0155] Furthermore, the curve showing the relationship between heart rate and output frequency shown in Figure 9(B) is composed of a combination (connection) of a sigmoid curve having an inflection point at the first threshold value n1 and a curve having an inflection point at the second threshold value n2 and asymptotic to a straight line passing through the origin.

[0156] In the output frequency determination process, the processor 61 may determine the output frequency f(n) corresponding to the heart rate n acquired in step ST2 using the following equation (3).

[0157]

number

[0158] In equation (3), f1 and f2 are the first and second frequencies, respectively, and ζ1(x) and ζ2(x) are the same sigmoid functions as in equation (1).

[0159] The processor 61 may determine the output frequency f(n) by substituting the heart rate n obtained in step ST2 into equation (3).

[0160] When the determination of the output amplitude is completed, the processor 61 executes the output process of step ST13 as shown in FIG.

[0161] In the output processing, the processor 61 generates digital signals to cause each of the vibrators 59 to output vibrations with the output amplitude determined in step ST11 and the output frequency determined in step ST12, and outputs the signals to the digital-to-analog converter 66. The digital-to-analog converter 66 generates analog signals corresponding to the input digital signals and inputs them to the corresponding vibrators 59. As a result, each of the vibrators 59 outputs vibrations with the output amplitude determined in step ST11 and the output frequency determined in step ST12.

[0162] After the processor 61 outputs the digital signal for a predetermined period of time, it ends the seat control process.

[0163] However, similar to the first embodiment, the processor 61 may continue to generate a digital signal even after the predetermined time has elapsed.

[0164] Next, the effects of the vehicle seat 26 configured as above, the seat system 1, the control method for the vehicle seat 26, and the control program for the vehicle seat 26 will be described.

[0165] As shown in Figures 9(A) and 9(B), when the heart rate decreases and approaches the first threshold n1, vibrations are generated from the vibration device 42. This can encourage the driver to wake up. When the heart rate increases and approaches the second threshold n2, vibrations with a frequency corresponding to the heart rate are generated from the vibration device 42. This transmits vibrations corresponding to the heart rate to the driver, encouraging the driver to relax.

[0166] In this way, it is possible to provide a vehicle seat 26, a seat system 1 including the vehicle seat 26, a control method for the vehicle seat 26, and a control program for the vehicle seat 26, which can encourage the driver to become awake when the driver's level of alertness is low and encourage the driver to relax when the driver is excited, thereby guiding the driver into a state suitable for driving operations.

[0167] In the second embodiment, when the heart rate approaches the first threshold value n1 or the second threshold value n2, the amplitude and frequency change gradually, thereby improving the comfort of the vehicle seat 26.

[0168] <<Third Embodiment>> The seat control process according to the third embodiment differs from the first embodiment in the method of setting the amplitudes in the awakening control and the guidance control, but other configurations are the same as those of the first embodiment, so a description of the other configurations will be omitted.

[0169] In the wakefulness control (step ST4), processor 61 sets the frequency to a first frequency f1, which is a constant, in the same manner as in the first embodiment.

[0170] In wakefulness control, processor 61 sets the output amplitude based on the graph showing the relationship between heart rate and output amplitude shown in Figure 10(A). In Figure 10(A), as the heart rate decreases below first threshold n1, the output amplitude gradually increases and is set to a constant value. The output amplitude set in wakefulness control may be represented by a sigmoid function (sigmoid curve) that uses heart rate as a variable.

[0171] In the guidance control (step ST6), the processor 61 sets the frequency to a second frequency f2 proportional to the heart rate, as in the first embodiment.

[0172] In the guidance control, the processor 61 sets the output amplitude based on the graph showing the relationship between the heart rate and the output amplitude shown in Fig. 10(A). In Fig. 10(A), as the heart rate becomes smaller than the second threshold n2, the output amplitude gradually increases and is set to a constant value. The output amplitude set in the guidance control may be represented by a sigmoid function (sigmoid curve) that uses the heart rate as a variable.

[0173] Next, the effects of the vehicle seat 26 configured as above, the seat system 1, the control method for the vehicle seat 26, and the control program for the vehicle seat 26 will be described.

[0174] As shown in Figures 10(A) and 10(B), when the heart rate decreases and becomes smaller than the first threshold value n1, vibration is generated from the vibration device 42. This can encourage the driver to wake up. When the heart rate increases and becomes larger than the second threshold value n2, vibration with a frequency corresponding to the heart rate is generated from the vibration device 42. As a result, vibrations corresponding to the heart rate are transmitted to the driver, which can encourage the driver to relax, for example.

[0175] In this way, it is possible to provide a vehicle seat 26, a seat system 1 including the vehicle seat 26, a control method for the vehicle seat 26, and a control program for the vehicle seat 26, which can encourage the driver to become awake when the driver's level of alertness is low and encourage the driver to relax when the driver is excited, thereby guiding the driver into a state suitable for driving operations.

[0176] In the third embodiment, similarly to the second embodiment, when the heart rate decreases and becomes smaller than the first threshold value n1, the amplitude is set to gradually approach a constant value from zero. Also, when the heart rate increases and exceeds the second threshold value n2, the amplitude is set to gradually approach a constant value from zero. This gradual change in amplitude improves the comfort of the vehicle seat 26.

[0177] Although the description of the specific embodiment has been completed above, the present invention is not limited to the above embodiment and can be widely modified and implemented. In the above embodiment, the seat control device 43 and the vehicle control device 4 are configured as separate devices, but they may be configured as a single control device. Furthermore, the seat control device 43 may be configured as multiple devices (computers).

[0178] In the above embodiment, the digital signal generated by the processor 61 is converted into an analog signal by the digital-to-analog converter 66 and output directly to the vibrator 59. However, various amplifiers, modulators, etc. may be provided between the digital-to-analog converter 66 and the vibrator 59. The processor 61 may be configured to control the amplifiers, modulators, etc. to cause the vibrator 59 to output vibrations with a set amplitude and wriggling frequency.

[0179] In the above embodiment, the processor 61 makes the determination in step ST1 based on the elapsed time, which is the time during which the vehicle has been manually driven. However, the determination may be made based on the distance traveled by manual driving instead of the elapsed time. The processor 61 may be configured to execute step ST2 when the distance traveled by manual driving is equal to or greater than a predetermined distance threshold. This makes it possible to prohibit the activation of the vibration device 42 when the distance traveled by manual driving is less than the distance threshold.

[0180] In the above embodiment, an example was described in which the seat control device 43 controls the independent variable vibrator 59C in both awakening control and induction control, but the seat control device 43 may also be configured to control the amplitude of the interlocking fixed vibrator 59D when performing awakening control, and to control the independent variable vibrator 59C to output vibrations with a frequency corresponding to the heart rate when performing induction control.

[0181] Furthermore, in the first embodiment described above, the amplitude of the vibration output from the vibration device 42 during the wakefulness control was configured to be constant regardless of the heart rate, but the amplitude may be set to increase (or decrease) as the heart rate decreases.

[0182] In the above embodiment, an example in which the heart rate sensor 35 is provided in the wearable terminal 25 (smart watch) has been described, but the present invention is not limited to this example, and the heart rate sensor 35 may be provided in the seat body 41 (preferably at least one of the seat back 47, the seat cushion 46, and the armrest). In this case, the heart rate sensor 35 may be connected to the seat control device 43 by a harness or the like, and the seat control device 43 may be configured to obtain the heart rate based on the detection result of the heart rate sensor 35.

[0183] In the first embodiment, the processor 61 is configured to execute the awakening control in step ST4 and the guidance control in step ST6, but may be configured to terminate the seat control process without executing the awakening control in step ST4. As a result, when the heart rate is higher than the second threshold (upper threshold), the processor 61 executes the guidance control to vibrate the vibration device 42 at a frequency corresponding to the heart rate. This can help an excited driver relax and guide the driver into a state suitable for driving.

[0184] In the second embodiment described above, the processor 61 determines the output amplitude using the graph shown in FIG. 9(A) in the output amplitude determination process, and determines the output frequency using the graph shown in FIG. 9(B) in the output frequency determination process. However, the processor 61 may determine the output amplitude using the graph shown in FIG. 11(A) in the output amplitude determination process, and may determine the output frequency using the graph shown in FIG. 11(B) in the output frequency determination process.

[0185] As a result, as shown in FIG. 11(A), when the heart rate increases and approaches the second threshold (upper threshold), the output amplitude of the vibration generated by the vibration device 42 gradually increases and is set to gradually approach a constant value.

[0186] 11(B), when the heart rate increases and approaches the second threshold (upper threshold), the frequency of the vibration generated by the vibration device 42 is set to asymptotically approach a function proportional to the heart rate. This can encourage an excited driver to relax, thereby guiding the driver into a state suitable for driving operations.

[0187] In this case, in the output amplitude determination process, the processor 61 may set the output amplitude A(n) corresponding to the heart rate n using the following equation (4).

[0188]

number

[0189] As in the second embodiment, in equation (4), A2 is a constant, and ζ2(x) is the sigmoid function expressed in equation (2). The graph in Figure 11(A) corresponds to equation (4) as a function of heart rate n.

[0190] In addition, in the output amplitude determination process, the processor 61 may set the output frequency f(n) corresponding to the heart rate n using the following equation (5).

[0191]

number

[0192] In equation (5), n is the heart rate, k is a proportionality constant, n2 is the second threshold (upper threshold), and ζ2(x) is the sigmoid function expressed by equation (2). The graph in Figure 11(B) corresponds to equation (5) as a function of heart rate n.

[0193] In the above embodiment, an example was described in which the seat system 1 was applied to a four-wheeled automobile, but the seat system 1 is applicable to various vehicles including buses, trucks, etc. that are equipped with a vehicle seat 26 and operated by a driver. [Explanation of symbols]

[0194] 1: Seat system 19: Car interior temperature sensor (an example of an interior temperature sensor) 20: Outside vehicle temperature sensor (example of an outside temperature sensor) 26: Vehicle seat 35: Heart rate sensor 41: Seat body 42: Vibration device 43: Seat control device (an example of a control device) 57: Seat sensor n1: First threshold n2: Second threshold

Claims

1. A vehicle seat, a seat body on which a driver sits; a vibration device provided on the seat body; a control device that acquires the driver's heart rate and controls the driving of the vibration device, When the heart rate is higher than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

2. 2. The vehicle seat according to claim 1, wherein the control device, in the induction control, sets the frequency of the vibration output by the vibration device so as to be directly proportional to the heart rate.

3. The vehicle seat according to claim 1 , wherein the control device reduces the frequency of the vibration output by the vibration device over time during the induction control.

4. 2. The vehicle seat according to claim 1, wherein the control device executes an awakening control to vibrate the vibration device to awaken the driver when the heart rate is equal to or lower than a lower threshold that is lower than the upper threshold.

5. 5. The vehicle seat according to claim 4, wherein the control device sets the frequency of the vibration output by the vibration device to a constant value during the wakefulness control.

6. A vehicle seat as described in any one of claims 1 to 5, wherein the control device acquires the elapsed time since the driver started operating the vehicle, and when the elapsed time is less than a predetermined time threshold, prohibits activation of the vibration device.

7. A vehicle seat as described in any one of claims 1 to 5, wherein the control device acquires information regarding whether or not the driver is smoking, and when it determines that the driver is smoking, it sets the upper threshold value higher than when the driver is not smoking.

8. The seat body is provided with a seating sensor that acquires information related to the seating area of ​​the driver, 6. The vehicle seat according to claim 4, wherein the control device, in the wakefulness control, sets the amplitude of the vibration output by the vibration device to be larger when the seating area acquired by the seating sensor is equal to or larger than a predetermined area threshold, compared to when the seating area is less than the area threshold.

9. The control device is connected to an outdoor temperature sensor that acquires an outdoor temperature, which is the temperature outside the passenger compartment; 6. The vehicle seat according to claim 4, wherein the control device sets the amplitude of the vibration output by the vibration device to be larger in the wakefulness control when the outdoor temperature is below a predetermined temperature threshold, compared to when the outdoor temperature is equal to or higher than the temperature threshold.

10. The control device is connected to an outdoor temperature sensor that acquires an outdoor temperature, which is the temperature outside the passenger compartment, and an indoor temperature sensor that acquires an indoor temperature, which is the temperature inside the passenger compartment; 6. The vehicle seat according to claim 4, wherein when the outdoor temperature is less than a predetermined first temperature threshold and the indoor temperature is less than a predetermined second temperature threshold, the control device sets the amplitude of the vibration output by the vibration device to be larger in the wakefulness control than when the outdoor temperature is equal to or greater than the first temperature threshold and the indoor temperature is equal to or greater than the second temperature threshold.

11. A vehicle seat, a seat body on which a driver sits; a vibration device provided on the seat body; a control device that acquires the driver's heart rate and controls the driving of the vibration device, The control device A vehicle seat in which, as the heart rate increases and approaches an upper threshold, the frequency of vibration generated by the vibration device is set to asymptotically approach a function proportional to the heart rate.

12. The vehicle seat according to claim 11, wherein the control device sets the frequency of the vibration generated by the vibration device to gradually approach a constant output value when the heart rate decreases and approaches a lower threshold value that is smaller than the upper threshold value.

13. a vehicle seat including a seat body on which a driver sits and a vibration device provided on the seat body; a heart rate sensor for acquiring a heart rate of the driver; A seat system including a control device that controls the driving of the vibration device, When the heart rate is greater than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

14. A method for controlling a vehicle seat including a seat body on which a driver sits, a vibration device provided in the seat body, and a control device that acquires a heart rate of the driver and controls driving of the vibration device, When the heart rate is greater than a predetermined upper threshold, the control device executes induction control to vibrate the vibration device at a frequency corresponding to the heart rate.

15. A control program for a vehicle seat including a seat body on which a driver sits, a vibration device provided in the seat body, and a control device that acquires a heart rate of the driver and controls driving of the vibration device, A control program for a vehicle seat, in which, when the heart rate is greater than a predetermined upper threshold, the control device executes guidance control to vibrate the vibration device at a frequency corresponding to the heart rate.

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