Motion sickness prevention device

Abstract

To reduce land sickness of occupants of a vehicle.SOLUTION: A motion sickness prevention device includes: an angle adjustment device that adjusts an angle of a backrest of a seat on which a passenger sits; and a control device for controlling driving of the angle adjustment device. The control device acquires information on vehicle vibrations, determines whether vibrations in a specified frequency range have continued for a specified period of time or longer, and when it determines that vibrations in the specified frequency range have continued for a specified period of time or longer, controls the drive of the angle adjustment device to change the angle of the backrest.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an anti-sickness device that reduces land sickness experienced by occupants of a vehicle. [Background technology]

[0002] Conventionally, various techniques have been proposed for preventing or reducing motion sickness that occurs while riding on a moving body such as an automobile or a ship. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-029210 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, there is a known phenomenon called land sickness, in which, when getting off a moving body such as a car or a ship, a person feels as if they are still on the moving body. Specifically, land sickness refers to a strange sensation that occurs when a person's sensory organs continue to receive the same vibration stimulus for a certain period of time while riding in a car or a ship, and the sensory organs become accustomed to the stimulus and become less sensitive to it, and when they get off the car or ship in this state, they suddenly no longer feel the stimulus.

[0005] There are four receptors in the skin that sense vibration stimuli, and each receptor adapts to the stimulus at a different speed. Merkel cells and Ruffini corpuscles in particular adapt slowly to stimuli, and are thought to be the cause of land sickness because they take a long time to adapt. In addition, Merkel cells and Ruffini corpuscles detect vibrations and deformations of approximately 15 Hz or less, and therefore have a large impact on the discomfort caused by vibration.

[0006] As described above, although technologies have been proposed for reducing motion sickness that occurs while riding a moving body, no technology has been proposed to reduce land sickness that occurs after getting off the moving body.

[0007] The present disclosure has been made in consideration of the above problems, and an object of the present disclosure is to provide a motion sickness prevention device that can reduce land sickness suffered by occupants of a moving body. [Means for solving the problem]

[0008] In order to solve the above problem, according to one aspect of the present disclosure, there is provided a motion sickness prevention device that reduces land sickness that occurs in a vehicle occupant after the occupant gets out of the vehicle, the motion sickness prevention device including an angle adjustment device that adjusts the angle of a backrest of a seat on which the occupant sits, and a control device that controls the drive of the angle adjustment device, wherein the control device acquires information about vibrations of the vehicle, performs a determination process to determine whether vibrations in a predetermined frequency range have continued for a predetermined period of time or more, and an angle change process that controls the drive of the angle adjustment device and changes the angle of the backrest when it is determined that vibrations in the predetermined frequency range have continued for a predetermined period of time or more. Effect of the Invention

[0009] As described above, according to the present disclosure, it is possible to reduce land sickness suffered by occupants of a moving vehicle. [Brief description of the drawings]

[0010] [Figure 1] 1 is an explanatory diagram showing a configuration example of a motion sickness prevention device according to a first embodiment of the present disclosure; [Diagram 2] 2 is a block diagram showing an example of the configuration of a control device of the motion sickness prevention device according to the embodiment. FIG. [Diagram 3] 5 is a flowchart showing a processing operation of a control device of the motion sickness prevention device according to the embodiment. [Figure 4] 13 is a flowchart showing an angle change process according to the embodiment. [Diagram 5]1 is an explanatory diagram showing the time difference between the time when a vehicle passes the peak of the road inclination and the time when an occupant changes the inclination of the face or line of sight; [Figure 6] 13 is a block diagram showing a configuration example of a control device of a motion sickness prevention device according to a second embodiment of the present disclosure. FIG. [Figure 7] 5 is a flowchart showing a processing operation of a control device of the motion sickness prevention device according to the embodiment. [Figure 8] 13 is a flowchart showing an angle change process according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a preferred embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are denoted by the same reference numerals to avoid repetitive explanation. In addition, in order to facilitate understanding of the technology of the present disclosure, the relative sizes and shapes of the components shown in each drawing have been appropriately changed, and the technology of the present disclosure is not limited to the configurations shown in the drawings.

[0012] <<1. First embodiment>> The motion sickness prevention device according to the first embodiment of the present disclosure includes an angle adjustment device that adjusts the angle of the backrest of the seat on which an occupant sits, and a control device that controls the drive of the angle adjustment device. The control device acquires information about the vibrations of the vehicle, performs a determination process to determine whether or not vibrations in a predetermined frequency range have continued for a predetermined period of time or more, and, when it is determined that vibrations in the predetermined frequency range have continued for a predetermined period of time or more, controls the drive of the angle adjustment device and executes an angle change process to change the angle of the backrest, thereby reducing land sickness that occurs in vehicle occupants after they get out of the vehicle.

[0013] The sickness reduction device of this embodiment is constructed as a device that suppresses the occurrence of land sickness by changing the angle of the seat back to change the direction of vibrations transmitted to the occupant when vibrations in a specified frequency range that may cause land sickness occur continuously for a specified period of time or more.

[0014] "Vibrations in a specific frequency range" refers to vibrations in a frequency range that can cause land or motion sickness, for example, vibrations in a frequency range of about 5 to 15 Hz. Also, "specific time" refers to the time during which vibrations in a specific frequency range continue and the passenger is likely to experience land sickness after getting off the vehicle, for example, about 60 to 120 seconds.

[0015] <1-1. Configuration> Fig. 1 is an explanatory diagram showing the overall configuration of a motion sickness prevention device 10 mounted on a vehicle 1, which is a moving body. Fig. 2 is a block diagram showing the functional configuration of the motion sickness prevention device 10.

[0016] The motion sickness prevention device 10 includes an angle adjustment device 11 for adjusting the angle of the backrest 5a of the seat 5 on which the occupant H sits, a vibration sensor 13, a vehicle condition sensor 15, a forward-facing camera 17, an interior camera 19, a learning data memory unit 23, a map data memory unit 25, and a control device 30.

[0017] (1-1-1. Angle adjustment device) The angle adjustment device 11 is driven by the control device 30 to adjust the angle of the backrest 5a of the seat 5. The angle adjustment device 11 is provided at the connection between the backrest 5a and the seat portion 5b, and adjusts the angle of the backrest 5a relative to the seat portion 5b. The angle adjustment device 11 may be, for example, a stepping motor, but is not particularly limited as long as it is a device that can adjust the angle by rotating the backrest 5a.

[0018] (1-1-2. Vibration sensor) The vibration sensor 13 is composed of one or more sensors that detect vibrations of the vehicle 1. The vibration sensor 13 is provided, for example, in the seat 5 and detects vibrations transmitted to the occupant H. However, if the correlation with the vibration of the seat 5 can be defined in advance, the vibration sensor 13 may be provided in the vehicle body (for example, a floor panel). The vibration sensor 13 generates a signal corresponding to the detected vibration and transmits the sensor signal to the control device 30. There is no particular limit to the type of sensor as long as it is capable of outputting a sensor signal corresponding to the vibration. For example, the vibration sensor 13 may be a sensor that detects displacement, speed, or acceleration in three axial directions, namely, the front-rear direction, the left-right direction (width direction), and the height direction of the vehicle 1. Alternatively, the vibration sensor 13 may be a sensor that detects the displacement of the seat 5.

[0019] (1-1-3. Vehicle condition sensor) The vehicle condition sensor 15 is composed of one or more sensors that detect the attitude and running condition of the vehicle 1. The vehicle condition sensor 15 detects at least the speed (vehicle speed), acceleration, and pitch angle of the vehicle 1. The pitch angle indicates the inclination of the vehicle 1 in the forward / rearward direction about an axis along the vehicle width direction of the vehicle 1. The vehicle condition sensor 15 generates a signal according to the detected condition value, and transmits the sensor signal to the control device 30.

[0020] (1-1-4. Front camera) The front photographing camera 17 generates a captured image of the area in front of the vehicle 1. The front photographing camera 17 includes an imaging element such as a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS), and outputs the generated captured image to the control device 30.

[0021] (1-1-5. In-car camera) The interior camera 19 generates captured images of the interior of the vehicle. The interior camera 19 includes an imaging element such as a CCD or a CMOS, and outputs the generated captured images to the control device 30. The interior camera 19 is installed in a position and orientation that allows it to capture an image of the occupant H.

[0022] (1-1-6. Learning data storage unit) The learning data storage unit 23 stores various data recorded by the learning processing unit 49 of the control device 30. The recording medium constituting the learning data storage unit 23 may be a magnetic medium such as a hard disk, a floppy disk, or a magnetic tape, an optical recording medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD (Digital Versatile Disk), or a Blu-ray (registered trademark), a magneto-optical medium such as a floptical disk, a memory element such as a RAM (Random Access Memory), a flash memory such as a USB (Universal Serial Bus) memory or an SSD (Solid State Drive), or any other writable and readable recording medium.

[0023] (1-1-7. Control device) The control device 30 functions as a device that drives the angle adjustment device 11 by executing a computer program using one or more processors such as a CPU (Central Processing Unit), thereby reducing land sickness of the occupant H. The computer program is a computer program for causing the processor to execute operations to be performed by the control device 30, which will be described later. The computer program executed by the processor may be recorded on a recording medium that functions as a storage unit (memory) provided in the control device 30, or may be recorded on a recording medium built into the control device 30 or any recording medium that can be externally attached to the control device 30.

[0024] Examples of recording media for recording computer programs include magnetic media such as hard disks, floppy disks, and magnetic tapes; optical recording media such as CD-ROMs, DVDs, and Blu-ray (registered trademark); magneto-optical media such as floptical disks; memory elements such as RAMs and ROMs; flash memories such as USB memories and SSDs; and other media capable of storing programs.

[0025] The control device 30 includes a vibration detection unit 31, a processing unit 33, and a storage unit . The vibration detection unit 31 executes a process of detecting vibrations occurring in the vehicle body based on the sensor signal output from the vibration sensor 13. For example, the vibration detection unit 31 is configured as a signal processing circuit including an amplifier, a band-pass filter, an A / D converter, etc., and extracts one or more vibrations, each having a predetermined frequency and amplitude, from the output waveform of the vibration sensor 13 by using a fast Fourier transform (FFT) or the like.

[0026] The storage unit 35 includes one or more storage elements such as RAM or ROM, and is communicably connected to the processing unit 33. However, the number and type of the storage units 35 are not particularly limited. The storage unit 35 stores information such as computer programs executed by the processing unit 33, various parameters used in the calculation processing, detection data, and calculation results. A part of the storage unit 35 is used as a work area for the processing unit 33.

[0027] The processing unit 33 is configured with one or more processors such as CPUs. A part or all of the processing unit 33 may be configured with updatable firmware or the like, or may be a program module or the like executed by instructions from the CPU or the like. The storage unit 35 is configured with one or more memories such as RAMs or ROMs.

[0028] 2, the processing unit 33 of the control device 30 includes a vibration determination unit 41, a driver information determination unit 43, a driving state determination unit 45, an angle change processing unit 47, and a learning processing unit 49. The vibration determination unit 41, the driver information determination unit 43, the driving state determination unit 45, the angle change processing unit 47, and the learning processing unit 49 are functions realized by execution of a computer program by a processor such as a CPU. However, part or all of the vibration determination unit 41, the driver information determination unit 43, the driving state determination unit 45, the angle change processing unit 47, and the learning processing unit 49 may be configured with analog circuits.

[0029] The vibration determination unit 41 acquires information on vibrations of the vehicle 1, and executes a determination process to determine whether or not vibrations in a predetermined frequency range have continued for a predetermined period of time or longer.

[0030] The driver information determination unit 43 executes a process of determining the direction of the face or gaze of the occupant H based on the captured image generated by the in-vehicle photographing camera 19. The process of determining the direction of the face or gaze of the occupant H may be executed using a conventionally known technique.

[0031] The driving state determination unit 45 executes a process of determining the inclination of the road on which the vehicle 1 travels. In this embodiment, the driving state determination unit 45 calculates the position of the peak of the inclination of the road on which the vehicle 1 travels and the time until the vehicle 1 reaches the peak, based on information on the pitch angle and acceleration of the vehicle 1 detected by the vehicle state sensor 15, information on the direction of the face or gaze of the occupant H, and the captured image generated by the front photographing camera 17. In addition, the driving state determination unit 45 calculates the inclination of the face or gaze of the occupant H when the vehicle 1 tilts in the front-rear direction, and calculates the time difference from when the vehicle 1 tilts to when the face or gaze of the occupant H tilts.

[0032] The inclination of the face or gaze indicates the inclination around an axis along the vehicle width direction of the vehicle 1, similar to the pitch angle of the vehicle 1, and indicates how much the direction of the face or gaze of the occupant H facing forward of the vehicle 1 has displaced in the up-down direction. For example, the driving state determination unit 45 calculates, as the inclination of the face or gaze of the occupant H when the vehicle 1 is traveling on flat ground as a reference direction, the angle that the direction of the face or gaze of the occupant H makes with respect to the reference direction when the vehicle 1 is tilted in the fore-and-aft direction.

[0033] When the vibration determination unit 41 determines that the vibration in the predetermined frequency range has continued for a predetermined period of time or more, the angle change processing unit 47 controls the driving of the angle adjustment device 11 and executes an angle change process to change the angle of the backrest 5a. By changing the angle of the backrest 5a, the direction or strength of the vibration transmitted to the occupant H via the seat 5 changes.

[0034] The learning processing unit 49 executes a learning process to learn the relationship between the information on the inclination of the road and the information on the line of sight or the face direction of the occupant H and record the relationship in the learning data storage unit 23.

[0035] <1-2. Operation> So far, an example of the configuration of the motion sickness prevention device 10 according to this embodiment has been described. Next, a specific operation of the motion sickness prevention device 10 will be described.

[0036] FIG. 3 is a flowchart showing the processing operation by the processing unit 33 of the control device 30. As shown in FIG. When the processing unit 33 detects the start of the system including the motion sickness prevention device 10 (step S11), it starts measurement by various sensors (step S13). Specifically, the vibration detection unit 31 of the processing unit 33 starts detecting vibrations occurring in the vehicle 1 based on the sensor signal output from the vibration sensor 13. In addition, the driver information determination unit 43 of the processing unit 33 starts measuring the direction of the face or line of sight of the occupant H based on the captured image generated by the in-vehicle shooting camera 19. In addition, the driving state determination unit 45 of the processing unit 33 starts measuring the longitudinal tilt of the vehicle 1 and the tilt of the face or line of sight of the occupant H based on the sensor signal indicating the acceleration and pitch angle of the vehicle 1 output from the vehicle state sensor 15 and the captured image generated by the front shooting camera 17.

[0037] The start-up of the system may be detected by the start-up switch of the vehicle 1 being turned on, or by the occupant H turning on a switch for activating the function of the motion sickness prevention device 10.

[0038] Next, the vibration determination unit 41 acquires the vibration information output from the vibration detection unit 31, and determines whether or not vibration in a predetermined frequency range is occurring (step S15). The predetermined frequency range is set in advance as a frequency range of vibration that is likely to cause land sickness or motion sickness. For example, the vibration determination unit 41 determines whether or not vibration with a frequency in the range of 5 to 15 Hz is occurring. The direction of the generated vibration is not particularly limited.

[0039] If the vibration determination unit 41 does not determine that vibration in the predetermined frequency range is occurring (S15 / No), the angle change processing unit 47 executes a return process to hold the backrest 5a of the seat 5 in its original position (step S23). Specifically, the angle change processing unit 47 holds the angle of the backrest 5a in the position before the angle change process was executed (hereinafter also referred to as the "initial setting position"). For example, if the angle of the backrest 5a is in the state before it was changed by the angle change process, the angle change processing unit 47 maintains the angle of the backrest 5a as it is.

[0040] On the other hand, if the angle of the backrest 5a has been changed by the angle change process, the angle change processing unit 47 drives the angle adjustment device 11 to return the angle of the backrest 5a to the initial position. At this time, it is preferable that the angle change processing unit 47 returns the angle of the backrest 5a to the initial position at a speed equal to or less than a predetermined angular velocity so as not to give a sense of discomfort to the occupant H. Alternatively, the angle change processing unit 47 may detect the timing when a strong vibration is applied to the vehicle 1 based on the image captured by the front-view camera 17, and return the angle of the backrest 5a to the initial position in accordance with the vibration.

[0041] After performing a return process to hold the backrest 5a of the seat 5 in its original position, the angle change processing unit 47 proceeds to step S25. When the vibration determination unit 41 does not determine that a vibration in the predetermined frequency range is occurring (S15 / No), it resets a timer counter that measures the duration of the vibration in the predetermined frequency range.

[0042] On the other hand, when it is determined that vibrations in the predetermined frequency range are occurring (S15 / Yes), the vibration determination unit 41 determines whether or not the vibrations in the predetermined frequency range have continued for a predetermined time or more since they started to occur (step S17). Specifically, the vibration determination unit 41 starts measuring the timer counter when the vibrations in the predetermined frequency range start to occur, and determines whether or not the measured value of the timer counter has reached the predetermined time each time the determination in step S15 is positive. The predetermined time is set in advance as an arbitrary time in the range of, for example, 60 to 120 seconds, as the time during which the vibrations in the predetermined frequency range continue and the occupant H is highly likely to develop land sickness after getting off the vehicle.

[0043] The vibration determination unit 41 may determine whether the condition of the road surface on which the vehicle 1 is traveling continues for a predetermined time or more in addition to determining whether the vibration in the predetermined frequency range has continued for a predetermined time or more since it started to occur. That is, the vibration determination unit 41 may determine whether the condition in which the same vibration is generated for the vehicle 1 continues for a predetermined time or more. The predetermined time may be set to an arbitrary time such as 1 to 2 minutes. The condition of the road surface may be determined based on an image captured by the front capturing camera 17, for example.

[0044] When the vibration determination unit 41 does not determine that the vibration in the predetermined frequency range has continued for a predetermined time or more (S17 / No), the process proceeds to step S25. On the other hand, when the vibration determination unit 41 determines that the vibration in the predetermined frequency range has continued for a predetermined time or more (S17 / Yes), the angle change processing unit 47 determines whether a predetermined time has passed since the angle of the backrest 5a of the seat 5 was last changed (step S19). Step S19 is provided to prevent the occupant H from feeling uncomfortable due to frequent changes in the angle of the backrest 5a, or to prevent changes in the angle of the backrest 5a from causing motion sickness. The predetermined time may be set to any value within a range of, for example, 120 to 300 seconds.

[0045] If the angle change processing unit 47 does not determine that a predetermined time has elapsed since the angle of the backrest 5a of the seat 5 was last changed (S19 / No), the process returns to step S15 while maintaining the angle of the backrest 5a regardless of the change in the upward or downward inclination. On the other hand, if the angle change processing unit 47 determines that a predetermined time has elapsed since the angle of the backrest 5a of the seat 5 was last changed (S19 / Yes), the process executes a process to change the angle of the backrest 5a of the seat 5 (step S21).

[0046] 4 is a flowchart showing a routine for processing to change the angle of the backrest 5a. First, the driving state determination unit 45 acquires measurement information (step S31). Specifically, the driving state determination unit 45 acquires a sensor signal indicating the acceleration and pitch angle of the vehicle 1 output from the vehicle state sensor 15, and information on the inclination of the vehicle 1 in the front-rear direction and the inclination of the face or line of sight of the occupant H measured by the driving state determination unit 45.

[0047] Next, the driving state determination unit 45 detects the peak of the inclination in the longitudinal direction of the road on which the vehicle 1 is traveling based on the acquired information (step S33). Specifically, the driving state determination unit 45 detects the peak of the inclination in the longitudinal direction of the road ahead of the traveling direction of the vehicle 1 based on the pitch angle and acceleration information of the vehicle 1 and the inclination information in the longitudinal direction of the road estimated based on the image captured by the front photographing camera 17. More specifically, the driving state determination unit 45 estimates the inclination of the road surface on which the vehicle 1 is currently traveling with respect to the horizontal direction based on the pitch angle and acceleration information of the vehicle 1. In addition, the driving state determination unit 45 estimates the inclination of the road ahead of the traveling direction of the vehicle 1, with the longitudinal direction of the vehicle 1 as the reference direction, based on the image captured by the front photographing camera 17.

[0048] Furthermore, the driving state determination unit 45 calculates the inclination of the road ahead in the traveling direction of the vehicle 1 with respect to the horizontal direction, based on the inclination of the road surface on which the vehicle 1 is currently traveling with respect to the horizontal direction and the inclination of the road ahead in the traveling direction of the vehicle 1 with the fore-and-aft direction of the vehicle 1 as a reference direction. Then, the driving state determination unit 45 identifies the position where the road changes from an upward slope or flat ground to a downward slope, or the position where the road changes from a downward slope or flat ground to an upward slope, as the position of the peak of the fore-and-aft direction inclination of the road.

[0049] At this time, if the inclination angle of the downward slope or upward slope after the change exceeds a preset angle threshold, the driving state determination unit 45 may identify the position where the road changes from an upward slope or flat ground to a downward slope, or the position where the road changes from a downward slope or flat ground to an upward slope, as the position of the peak of the road's longitudinal inclination. This makes it difficult for a slight change in the inclination angle to be detected as the peak of the road's longitudinal inclination.

[0050] In addition, if the vehicle 1 is equipped with map data having data on the inclination of the road and a vehicle position sensor that detects the position of the vehicle 1 on the map data, the driving state determination unit 45 may detect the peak of the longitudinal inclination of the road on which the vehicle 1 is traveling based on the map data.

[0051] Next, the driving state determination unit 45 calculates the time until the vehicle 1 reaches the peak of the road gradient (step S35). Specifically, the driving state determination unit 45 obtains the distance from the current position of the vehicle 1 to the position of the peak identified in step S33 based on the image captured by the forward photographing camera 17 or the sensor signal of another distance measuring sensor, and divides the distance by the vehicle speed of the vehicle 1 to calculate the time until the vehicle 1 reaches the peak of the road gradient.

[0052] Next, the angle change processing unit 47 judges whether the direction of the road inclination after the peak is the opposite direction to the direction of the inclination when the angle of the backrest 5a was changed last time (step S37). Specifically, when the road inclination after the currently detected peak is an upward inclination, the angle change processing unit 47 judges whether the road inclination after the peak when the angle of the backrest 5a was changed last time was a downward inclination, and conversely, when the road inclination after the currently detected peak is a downward inclination, whether the road inclination after the peak when the angle of the backrest 5a was changed last time was an upward inclination.

[0053] When the angle change processing unit 47 determines that the inclination direction of the road after the peak is the opposite direction to the inclination direction when the angle of the backrest 5a was changed last time (S37 / Yes), the process proceeds to step S41. On the other hand, when the angle change processing unit 47 does not determine that the inclination direction of the road after the peak is the opposite direction to the inclination direction when the angle of the backrest 5a was changed last time (S37 / No), the angle change processing unit 47 sets the angle of the backrest 5a to return to its original position (step S39). In other words, when the inclination direction of the road after the peak is the same direction twice consecutively, the angle change processing unit 47 avoids changing the angle of the backrest 5a in the same direction consecutively and sets the angle of the backrest 5a to return to its original position. This makes it possible to prevent the visibility from being deteriorated due to the angle of the backrest 5a becoming too large.

[0054] Next, the angle change processing unit 47 sets the time (change time) to complete the change in the angle of the backrest 5a based on the learning data that has learned the relationship between the inclination of the road and the direction of the face or gaze of the occupant H (step S41). Specifically, the angle change processing unit 47 refers to information on the time difference between the time when the vehicle 1 passes the peak of the inclination of the road and the time when the occupant H changes the inclination of his face or gaze, which is previously recorded in the learning data storage unit 23, and sets the time difference as the change time.

[0055] FIG. 5 is a diagram shown for explaining the time difference between the time when the vehicle 1 passes the peak of the road inclination and the time when the occupant H changes the inclination of his / her face or line of sight. When the vehicle 1 alternately travels uphill and downhill as shown in FIG. 5, for example, when passing a peak where an uphill slope changes to a downhill slope, a time difference may occur between the timing when the vehicle 1 starts to tilt and the timing when the occupant H tilts the direction of the face or gaze. As an example, as shown in the lower part of FIG. 5, when the vehicle 1 passes the peak, the front-rear direction of the vehicle 1 faces the horizontal direction, and the face or gaze of the occupant H faces forward in the traveling direction of the vehicle 1. When the vehicle 1 passes the peak position and starts to tilt, the face or gaze of the occupant H maintains the face or gaze direction when the vehicle 1 was at the peak position. Thereafter, as the tilt of the vehicle 1 becomes larger, the face or gaze of the occupant H changes to the direction in which the vehicle 1 tilts. The learning processing unit 49 described later calculates the time difference based on the measurement data and records it in the learning data storage unit 23.

[0056] The time difference between the time when the vehicle 1 passes the peak of the road inclination and the time when the occupant H changes the inclination of his / her face or gaze may differ depending on the vehicle speed or acceleration of the vehicle 1, or the inclination angle of the road after the peak. For this reason, it is desirable for the angle change processing unit 47 to refer to information on the above-mentioned time difference when the occupant H previously drove on a road where the inclination angle of the road after the peak was within a predetermined error.

[0057] The time to complete the change in the angle of the backrest 5a may be set to a fixed time. However, by setting the time difference between the time when the vehicle 1 passes the peak of the road inclination and the time when the occupant H changes the inclination of his / her face or line of sight as the change time, the direction of the face or line of sight of the occupant H forward in the traveling direction can be adjusted to the driving characteristics of the occupant H without significantly changing the angle of the face or line of sight of the occupant H relative to the front-rear direction of the vehicle 1.

[0058] Next, the angle change processing unit 47 determines whether or not the vehicle 1 has reached the peak position detected in step S33 (step S43). The angle change processing unit 47 determines that the vehicle 1 has reached the peak position when the time calculated in step S35 has elapsed. The angle change processing unit 47 may determine that the vehicle 1 has reached the peak position based on an image captured by the front imaging camera 17. Alternatively, if the vehicle 1 is equipped with map data and a vehicle position sensor that detects the position of the vehicle 1 on the map data, the angle change processing unit 47 may determine that the vehicle 1 has reached the peak position based on the map data.

[0059] When the angle change processing unit 47 does not determine that the vehicle 1 has reached the peak position (S43 / No), it repeats the determination of step S43. On the other hand, when the angle change processing unit 47 determines that the vehicle 1 has reached the peak position (S43 / Yes), it changes the angle of the backrest 5a (step S45). In other words, the angle change processing unit 47 starts changing the angle of the backrest 5a in accordance with the timing when the vehicle 1 passes the peak of the road inclination and starts to incline.

[0060] When the angle change processing unit 47 sets the angle of the backrest 5a to return to the original position in step S39, the angle change processing unit 47 returns the angle of the backrest 5a to the original position during the change time set in step S41. That is, the angle change processing unit 47 returns the angle of the backrest 5a to the original position in accordance with the timing when the inclination of the road changes. This prevents the occupant H from feeling uncomfortable.

[0061] Furthermore, if the angle change processing unit 47 makes a positive determination in step S37, it changes the angle of the backrest 5a in accordance with the change in the direction of the face or line of sight of the occupant H or the change in the pitch angle of the vehicle 1 during the change time set in step S41. At this time, the angle change processing unit 47 may change the angle of the backrest 5a in the same direction as the tilt of the vehicle 1, or in the opposite direction to the tilt of the vehicle 1. However, it is prevented from changing the angle of the backrest 5a in the same direction twice in succession. This prevents the visibility from becoming poor.

[0062] In addition, the angle change processing unit 47 may set a target value for the angle of the backrest 5a so that the occupant H can maintain the direction of his / her face or line of sight when traveling uphill or downhill, while keeping the direction of his / her face or line of sight when traveling on flat ground, based on the learning data of the direction of his / her face or line of sight recorded in the learning data storage unit 23 in the past. In this case, the angle of the backrest 5a is changed in the direction in which the vehicle 1 tilts, at the same angle as the inclination of the vehicle 1. However, an upper limit may be set for the angle at which the backrest 5a is changed, so that the angle of the backrest 5a is not changed too much. This makes it possible to prevent the visibility from becoming too poor.

[0063] Returning to FIG. 3, after the angle change processing unit 47 executes the process of changing the backrest angle in step S21, the process proceeds to step S25.

[0064] After a negative judgment is made in step S15 and the angle of the backrest 5a is maintained in its original position in step S23, or after a negative judgment is made in step S17, or after the angle change process is executed in step S21, the learning processing unit 49 associates the inclination of the road measured in the current calculation cycle (after the time when the measurement data was previously recorded in the learning data memory unit 23) with the data on the direction of the occupant H's face or gaze, and records them in the learning data memory unit 23 (step S25).

[0065] The learning data storage unit 23 contains measurement data of the direction of the face or gaze of the occupant H when the vehicle 1 is traveling on an uphill or downhill slope, and information on the time difference between the time when the vehicle 1 passes the peak of the road slope and the time when the occupant H changes the inclination of the face or gaze. The information recorded in the learning data storage unit 23 is referred to in the above-mentioned steps S41 and S45.

[0066] Next, the processing unit 33 determines whether the system including the motion sickness prevention device 10 has stopped (step S27), and returns to step S15 unless it determines that the system has stopped (S27 / Yes), and repeats the processing of each step described above. On the other hand, if the processing unit 33 determines that the system including the motion sickness prevention device 10 has stopped (S27 / Yes), it ends the series of processes.

[0067] As described above, the motion sickness prevention device 10 according to the first embodiment includes the angle adjustment device 11 that adjusts the angle of the backrest 5a of the seat 5 on which the occupant H sits, and the control device 30 that controls the drive of the angle adjustment device 11. The control device 30 also acquires information on the vibration of the vehicle 1, and executes a determination process for determining whether or not the vibration in a predetermined frequency range has continued for a predetermined time or more, and an angle change process for controlling the drive of the angle adjustment device 11 and changing the angle of the backrest 5a when it is determined that the vibration in the predetermined frequency range has continued for a predetermined time or more. Therefore, the direction or magnitude of the vibration transmitted to the occupant H via the seat 5 changes, and it is possible to prevent the sensory organs of the occupant H from adapting to the stimulation of the vibration, and it is possible to suppress land sickness when the occupant H gets off the vehicle 1.

[0068] Furthermore, the motion sickness prevention device 10 according to this embodiment has a configuration in which, when changing the angle of the backrest 5a, the angle is changed in the opposite direction to the direction in which the angle was changed the previous time, which prevents the field of view from being impaired by an excessive change in the angle of the backrest 5a.

[0069] The motion sickness prevention device 10 according to this embodiment is configured to determine the inclination of the road on which the vehicle 1 is traveling in the front-rear direction relative to the horizontal direction, and change the angle of the backrest 5a in accordance with the timing when the road changes to an upward or downward inclination. Therefore, the angle of the backrest 5a of the seat 5 is changed together with the inclination of the vehicle 1 after the vehicle 1 starts to incline, thereby reducing the change in the direction of the face or line of sight of the occupant H and reducing the discomfort of the occupant H.

[0070] Furthermore, the motion sickness prevention device 10 according to this embodiment has a configuration for setting the angle and the rate of change when changing the angle of the backrest 5a based on learning data recorded in association with information on the inclination of the road and information on the direction of the face or gaze of the occupant H. This can reduce the discomfort felt by the occupant H and prevent the visibility of the occupant H from becoming poor.

[0071] <<2. Second embodiment>> Next, a motion sickness prevention device according to a second embodiment of the present disclosure will be described. The motion sickness prevention device according to this embodiment is configured to learn vibration data measured while the vehicle 1 is traveling in association with the traveling position of the vehicle 1, and when the vehicle 1 travels on a road on which the vibration data is recorded, determine a point where vibration in a predetermined frequency range continues for a predetermined time or more based on the traveling position of the vehicle and the vibration data, change the angle of the seat backrest, and further determine a point where the vibration stops after the vibration in the predetermined frequency range continues for a predetermined time or more, and return the angle of the seat backrest to its original position.

[0072] <2-1. Configuration> 6 is a block diagram showing the functional configuration of the motion sickness prevention device 50 according to this embodiment. The motion sickness prevention device 50 includes a vehicle position sensor 21 and a map data storage unit 25 in addition to the functions of the motion sickness prevention device 50 according to the first embodiment.

[0073] The vehicle position sensor 21 receives satellite signals transmitted from satellites of a Global Navigation Satellite System (GNSS) such as a Global Positioning System (GPS), and detects position information of the vehicle 1. The position information of the vehicle 1 is specified as, for example, latitude and longitude information. The vehicle position sensor 21 outputs the detected position information of the vehicle 1 to the control device 30.

[0074] The map data storage unit 25 stores map data including at least road information. The road information included in the map data includes information on the inclination angle of the road (the inclination angle along the direction in which the road extends) associated with information on latitude and longitude. The recording medium constituting the map data storage unit 25 may be a magnetic medium such as a hard disk, a floppy disk, or a magnetic tape, an optical recording medium such as a CD-ROM, a DVD, or a Blu-ray (registered trademark), a magneto-optical medium such as a floptical disk, a memory element such as a RAM or a ROM (Read Only Memory), a flash memory such as a USB memory or an SSD, or other recording medium capable of being written and read.

[0075] In this embodiment, the learning data storage unit 23 stores data of vibrations measured by the vibration sensor 13 in association with the vehicle speed and acceleration of the vehicle 1 and the position information of the vehicle 1, together with the data stored in the learning data storage unit 23 in the first embodiment. That is, the vibration data storage unit 27 stores information on the position of the road on which the vehicle 1 has traveled, information on the traveling state of the vehicle 1 while traveling, and information on the generated vibrations in association with each other. Furthermore, the learning data storage unit 23 stores the position of the peak of the road, the inclination direction of the road after passing the peak, and the direction, amount (angle) and timing of the displacement when the angle of the backrest 5a is changed in association with the vehicle speed and acceleration of the vehicle 1 and the position information of the vehicle 1.

[0076] <2-2. Operation> Next, a specific operation of the motion sickness prevention device 50 according to this embodiment will be described.

[0077] FIG. 7 is a flowchart showing the processing operation by the processing unit 33 of the control device 30. As shown in FIG. As in the first embodiment, when the processing unit 33 detects the start-up of the system including the motion sickness prevention device 50 (step S11), it starts measurements by various sensors (step S13).

[0078] Next, the vibration determination unit 41 determines whether or not there is learning data on vibrations on the road on which the vehicle 1 is traveling, based on the position information of the vehicle 1 detected by the vehicle position sensor 21 (step S14). Specifically, after identifying the traveling position and traveling direction of the vehicle 1, the vibration determination unit 41 refers to the learning data recorded in the learning data storage unit 23 and determines whether or not learning data on vibrations on the road on which the vehicle 1 is traveling is recorded.

[0079] When the vibration determination unit 41 does not determine that there is learning data of vibration of the road on which the vehicle 1 is traveling (S14 / No), the process proceeds to step S15 of the flowchart shown in Fig. 3, and proceeds with the process described in the first embodiment. In this case, in step S25, the learning processing unit 49 records the measured vibration data, the position of the peak of the road and the inclination direction of the road after passing the peak, as well as the direction of displacement when the angle of the backrest 5a is changed, the amount of displacement (angle), and the timing of the change in association with the traveling position, vehicle speed, and acceleration of the vehicle 1. As a result, the learning data storage unit 23 accumulates data of vibrations generated according to the traveling position of the vehicle 1 and data of the change in the angle of the backrest 5a.

[0080] On the other hand, when the vibration determination unit 41 determines that there is learning data of vibration of the road on which the vehicle 1 is traveling (S14 / Yes), it determines whether or not there is a point in the traveling direction of the vehicle 1 where vibration in a predetermined frequency range continues for a predetermined time or more (step S51). In other words, the vibration determination unit 41 determines whether or not there is a point where the duration of vibration in the predetermined frequency range will reach a predetermined time if the vehicle 1 continues traveling as it is. When the vibration determination unit 41 does not determine that there is a point in the traveling direction of the vehicle 1 where vibration in the predetermined frequency range continues for a predetermined time or more (S51 / No), it returns to step S14.

[0081] On the other hand, if the vibration determination unit 41 determines that there is a point in the traveling direction of the vehicle 1 where vibrations in a predetermined frequency range continue for more than a predetermined period of time (S51 / Yes), it executes a process to change the angle of the backrest 5a (step S53).

[0082] FIG. 8 shows a flowchart of a process for changing the angle of the backrest 5a. In this embodiment, the angle change processing unit 47 refers to the learning data stored in the learning data storage unit 23 and sets the timing for changing the angle of the backrest 5a and the angle of the backrest 5a after the change (step S61). That is, the angle change processing unit 47 acquires the position where the angle of the backrest 5a is changed according to the peak of the road from the learning data recorded in the past, and calculates the time when the vehicle 1 reaches the position. The angle change processing unit 47 also reads out the angle of the backrest 5a set when the angle of the backrest 5a was changed at the position from the learning data recorded in the past, and sets it as the angle of the backrest 5a after the change.

[0083] Next, the angle change processing unit 47 judges whether or not the timing to change the angle of the backrest 5a has arrived (step S63). The angle change processing unit 47 repeats the judgment of step S63 until it judges that the timing to change the angle of the backrest 5a has arrived, and when it judges that the timing to change the angle of the backrest 5a has arrived (S63 / Yes), it changes the angle of the backrest 5a to the set angle (step S65). In this way, when the vehicle 1 travels on the same road, the angle of the backrest 5a can be changed to an appropriate angle at the same timing by alternating the tilt direction for changing the angle of the backrest 5a.

[0084] 7, the angle change processing unit 47 determines whether or not there is a point in the traveling direction of the vehicle 1 where the vibration in the predetermined frequency range stops (step S55). That is, the angle change processing unit 47 determines whether or not there is a point where the frequency range of the generated vibration will deviate from the predetermined frequency range if the vehicle 1 continues traveling as is. If the angle change processing unit 47 does not determine that there is a point in the traveling direction of the vehicle 1 where the vibration in the predetermined frequency range stops (S55 / No), it returns to step S53 and continues the angle change processing.

[0085] On the other hand, when the angle change processing unit 47 determines that there is a point where the vibration in the predetermined frequency range stops in the traveling direction of the vehicle 1 (S55 / Yes), it returns the angle of the backrest 5a to the original position before the angle change processing was executed when the vehicle 1 passes the next peak (step S57). By returning the angle of the backrest 5a to the original position in time with the passing of the peak, it is possible to reduce the discomfort felt by the occupant H. The angle change processing unit 47 may return the angle of the backrest 5a to the initial position at a speed equal to or lower than a predetermined angular velocity after the vehicle 1 passes the point where the vibration in the predetermined frequency range stops.

[0086] Next, the processing unit 33 determines whether the system including the motion sickness prevention device 50 has stopped (step S59), and returns to step S14 unless it determines that the system has stopped (S59 / Yes), and repeats the processing of each step described above. On the other hand, if the processing unit 33 determines that the system including the motion sickness prevention device 50 has stopped (S59 / Yes), it ends the series of processes.

[0087] As described above, the motion sickness prevention device 50 according to the second embodiment learns the vibration data measured by the vibration sensor 13, the position of the peak of the road and the inclination direction of the road after passing the peak, as well as the direction of displacement when changing the angle of the backrest 5a, the amount of displacement (angle), and the timing of the change in association with the position information of the vehicle 1. Then, the motion sickness prevention device 50 sets the timing of changing the angle of the backrest 5a and the angle of the backrest 5a to be changed based on the learned data, and changes the angle of the backrest 5a according to the traveling position of the vehicle 1. As a result, when the vehicle 1 travels on the same road, the angle of the backrest 5a can be changed to an appropriate angle at the same timing by alternating the direction of the inclination for changing the angle of the backrest 5a. As a result, it is possible to prevent the sensory organs of the occupant H from adapting to the stimulation of the vibration, and to suppress land sickness when the occupant H gets off the vehicle 1.

[0088] <<3. Modifications>> Up to this point, the motion sickness prevention device according to the first embodiment and the second embodiment has been described, but the above-mentioned embodiments can be modified in various ways. Below, some modified examples of the motion sickness prevention device according to the above-mentioned embodiments will be described.

[0089] The motion sickness prevention device 10 according to the first embodiment starts changing the angle of the backrest 5a when the vehicle 1 passes the peak of the road inclination based on the image captured by the forward-facing camera 17 or the road inclination information of the map data, and the motion sickness prevention device 50 according to the second embodiment starts changing the angle of the backrest 5a based on the learning data. The motion sickness prevention device may obtain pitch angle information of the vehicle 1 output from the vehicle state sensor 15, and change the angle of the backrest 5a when the detected inclination of the vehicle 1 in the front-rear direction exceeds a predetermined angle threshold. This method also makes it possible to change the magnitude or direction of the vibration transmitted to the occupant H via the seat 5, although the timing of starting to change the angle of the backrest 5a is delayed compared to the above embodiments, and it is possible to prevent the sensory organs of the occupant H from adapting to the vibration stimulus.

[0090] The motion sickness prevention device may also predict that the road on which the vehicle 1 travels will change to an upward or downward slope based on the acceleration of the vehicle 1 in the forward or backward direction detected by the vehicle state sensor 15, and change the angle of the backrest 5a in accordance with the timing of the road changing to an upward or downward slope. In other words, the vehicle 1 may naturally decelerate when the road on which the vehicle 1 travels changes to an upward slope, and the vehicle 1 naturally accelerates when the road on which the vehicle 1 travels changes to a downward slope, to predict the timing at which the vehicle 1 passes the peak of the road slope. Although this method may cause a shift in the timing at which the angle of the backrest 5a is changed, it is possible to change the magnitude or direction of the vibration transmitted to the occupant H via the seat 5, and to prevent the occupant H's sensory organs from adapting to the vibration stimulus.

[0091] Although the preferred embodiment of the present disclosure has been described in detail above with reference to the attached drawings, the technology of the present disclosure is not limited to such examples. It is clear that a person having ordinary knowledge in the technical field to which the present disclosure belongs can conceive of various modified or amended examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present disclosure.

[0092] For example, in each of the above embodiments, all the components of the motion sickness prevention device are provided in the vehicle, but the learning data storage unit may be provided in an external server that can communicate with the vehicle via a mobile communication means, thereby making it possible to share learning data between different vehicles.

[0093] In addition, the technology disclosed herein can also be realized as a vehicle equipped with the motion sickness prevention device described in the above embodiments, a motion sickness prevention method using the motion sickness prevention device, a computer program that causes a computer to function as the above-mentioned control device, and a non-transitory tangible recording medium on which the computer program is recorded. [Explanation of symbols]

[0094] 1: Vehicle 5: Seat 5a: Backrest 10: Motion sickness prevention device 11: Angle adjustment device 13: Vibration sensor 15: Vehicle status sensor 17: Front camera 19: In-car camera 21: Vehicle position sensor 23: Learning data storage unit 25: Map data storage unit 27: Vibration data storage unit 30: Control device 31: Vibration detection unit 33: Processing section 35: Storage section 41: Vibration determination section 43: Driver information determination unit 45: Driving state determination unit 47: Angle change processing section 49: Learning processing section 50: Motion sickness prevention device

Claims

1. A vehicle sickness prevention device for reducing land sickness caused by a vehicle occupant after the occupant gets out of the vehicle, an angle adjustment device for adjusting the angle of the backrest of the seat on which the passenger sits; A control device for controlling the drive of the angle adjustment device, The control device includes: a determination process of acquiring information on vibration of the vehicle and determining whether or not vibration in a predetermined frequency range has continued for a predetermined period of time or more; an angle change process for controlling the drive of the angle adjustment device and changing the angle of the backrest when it is determined that the vibration in the predetermined frequency range has continued for a predetermined time or more; An anti-sickness device that performs the following:

2. The control device, in the angle change process, determining an inclination of a road on which the vehicle is traveling in a front-rear direction of the vehicle relative to a horizontal direction, and changing an angle of the backrest in accordance with a timing at which the road changes to an upward incline or a downward incline; The motion sickness prevention device according to claim 1.

3. The control device, in the angle change process, acquiring information on the inclination of the vehicle relative to a horizontal direction detected by a sensor; changing the angle of the seat back when the detected inclination of the vehicle in the longitudinal direction exceeds a predetermined angle threshold value; The motion sickness prevention device according to claim 2.

4. The control device, in the angle change process, Acquire information on acceleration of the vehicle in a forward / rearward direction; predicting whether the road on which the vehicle is traveling will change to an upward or downward slope based on the acceleration of the vehicle in the forward or backward direction; changing the angle of the backrest in accordance with the timing of the change to the upward inclination or downward inclination; The motion sickness prevention device according to claim 2.

5. The motion sickness prevention device includes: A learning data storage unit stores learning data obtained by learning a relationship between the inclination of the road and the face or gaze direction of the occupant, The control device, in the angle change process, estimating the inclination of the upward inclination or the downward inclination, and setting a target value of the angle of the backrest based on the learning data, thereby changing the angle of the backrest. The motion sickness prevention device according to claim 2.

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