Vehicle seat control device

Abstract

To appropriately control an inclination angle of a seat so as to reduce a physical burden of an occupant while suppressing sense of incongruity of the occupant.SOLUTION: A seat control device for a vehicle includes: an angle calculation unit that calculates an angle at which resultant force of vehicle acceleration and gravitational acceleration is perpendicular to a seat surface of a seat, a seat inclination angle calculation unit that calculates an inclination angle of the seat by multiplying the angle calculated by the angle calculation unit by a gain that is changed under a predetermined condition, and a seat control unit that inclines the seat at the inclination angle calculated by the seat inclination angle calculation unit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a seat control device for a vehicle. [Background technology]

[0002] The following Patent Document 1 discloses a technology that calculates the tilt angle at which car sickness is suppressed from the vehicle's longitudinal acceleration, and guides the occupant seated in the vehicle seat to adjust the seat angle so that the tilt angle of the head and trunk of the occupant is equal to or greater than the calculated tilt angle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-056938 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the technology of Patent Document 1, even if the occupant adjusts the seat angle as instructed, the seat may not necessarily be at the appropriate inclination angle depending on the condition of the occupant and the vehicle, which may cause the occupant to feel uncomfortable. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a seat control device for a vehicle according to one embodiment includes an angle calculation unit that calculates the angle at which the resultant force of vehicle acceleration and gravitational acceleration becomes perpendicular to the seat surface, a seat inclination angle calculation unit that calculates the inclination angle of the seat by multiplying the angle calculated by the angle calculation unit by a gain that is changed under predetermined conditions, and a seat control unit that tilts the seat by the inclination angle calculated by the seat inclination angle calculation unit. [Effects of the Invention]

[0006] According to the vehicle seat control device of one embodiment, the tilt angle of the seat can be appropriately controlled so as to reduce the physical burden on the occupant while suppressing any discomfort felt by the occupant. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a configuration of a vehicle according to an embodiment; [Figure 2] 1 is a flowchart illustrating an example of a processing procedure performed by a seat control ECU according to an embodiment; [Figure 3] FIG. 10 is a diagram illustrating a class determination logic for determining a gain by a seat control ECU according to an embodiment. [Figure 4] Graph for determining gains by a seat control ECU according to an embodiment [Figure 5] 10 is a flowchart showing an example of a procedure of processing by a seat control ECU according to a first modified example. [Figure 6] FIG. 10 is a diagram showing a class determination logic for determining a gain by a seat control ECU according to a first modified example. [Figure 7] Graph for determining gains by a seat control ECU according to a first modification [Figure 8] 10 is a flowchart showing an example of a procedure of processing by a seat control ECU according to a second modified example. [Figure 9] FIG. 10 is a diagram showing an example of a gain setting screen displayed by a seat control ECU according to a second modified example; DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] (Configuration of vehicle 10) Fig. 1 is a diagram showing the configuration of a vehicle 10 according to one embodiment. The vehicle 10 shown in Fig. 1 is, for example, an electrically powered vehicle such as a hybrid vehicle, a fuel cell vehicle, or an electric vehicle, which is equipped with a motor generator 16 for driving wheels 17 and a battery 15.

[0010] As shown in FIG. 1, a vehicle 10 includes an active seat 11, a vehicle control ECU (Electronic Control Unit) 13, an IMU (Inertial Measurement Unit) 14, a battery 15, a motor generator 16, wheels 17, and a seat control ECU 20.

[0011] The active seat 11 is an example of a "vehicle seat." The active seat 11 is provided in the cabin of the vehicle 10, and an occupant can sit in it. The active seat 11 has a seat drive device 11A that can control the tilt of the active seat 11 in the front-rear and left-right directions.

[0012] The vehicle control ECU 13 controls each part of the vehicle 10. For example, the vehicle control ECU 13 can control the drive torque of wheels 17 provided on the vehicle 10 by controlling the output torque of a motor generator 16 provided on the vehicle 10.

[0013] The IMU 14 measures three-dimensional inertial motion of the vehicle 10. For example, the IMU 14 can measure three-axial vehicle acceleration (translational motion) using a three-axis acceleration sensor. Also, for example, the IMU 14 can measure three-axial vehicle angular velocity (rotational motion) using a three-axis gyro sensor.

[0014] The battery 15 stores the electric power to be supplied to each part of the vehicle 10. As the battery 15, for example, a secondary battery such as a lithium ion battery or a nickel-metal hydride battery is used.

[0015] The seat control ECU 20 is an example of a "seat control device." The seat control ECU 20 controls the tilt of the active seat 11 in response to acceleration / deceleration, left / right turns, road vibrations, etc. of the vehicle 10, thereby reducing the physical burden on the occupant seated in the active seat 11.

[0016] The seat control ECU 20 includes an angle calculation unit 21, a gain determination unit 22, a seat tilt angle calculation unit 23, and a seat control unit 24.

[0017] The angle calculation unit 21 calculates the angle θ1 at which the resultant force of the vehicle acceleration measured by the IMU 14 and the gravitational acceleration G becomes perpendicular to the seating surface of the active seat 11 (i.e., the angle θ1 at which the gravitational acceleration G is cancelled out). For example, the angle calculation unit 21 calculates the angle θ1 at which the gravitational acceleration G is cancelled out by the following equation (1), where a represents the vehicle acceleration measured by the IMU 14.

[0018] θ1=tan -1 (a / G)···(1)

[0019] The gain determination unit 22 calculates a gain k that is changed under predetermined conditions. In this embodiment, the gain determination unit 22 calculates the gain k according to conditions related to the occupant's field of view. In this embodiment, examples of the conditions related to the occupant's field of view include whether the occupant's eyes are covered, whether the occupant's eyes are open, and whether the occupant's line of sight is forward.

[0020] The seat tilt angle calculation unit 23 calculates the tilt angle θ2 of the active seat 11 by multiplying the angle θ1 calculated by the angle calculation unit 21 by the gain k determined by the gain determination unit 22.

[0021] The seat control unit 24 controls the seat drive device 11A provided in the active seat 11 to tilt the active seat 11 by the tilt angle θ2 calculated by the seat tilt angle calculation unit 23.

[0022] (Example of processing procedure by the seat control ECU 20) FIG. 2 is a flowchart showing an example of a procedure of processing by the seat control ECU 20 according to an embodiment.

[0023] First, the seat control ECU 20 acquires the vehicle acceleration measured by the IMU 14 (step S201).

[0024] Next, the angle calculation unit 21 of the seat control ECU 20 calculates the angle θ1 at which the resultant force of the vehicle acceleration and the gravitational acceleration G acquired in step S201 becomes perpendicular to the seating surface of the active seat 11 (i.e., the angle θ1 that cancels the gravitational acceleration G) (step S202).

[0025] Next, the gain determination unit 22 of the seat control ECU 20 determines the gain k according to conditions related to the visibility of the occupant (step S203).

[0026] Next, the seat tilt angle calculation unit 23 of the seat control ECU 20 calculates the tilt angle θ2 of the active seat 11 by multiplying the angle θ1 calculated in step S202 by the gain k determined in step S203 (step S204).

[0027] Next, the seat control unit 24 of the seat control ECU 20 controls the seat drive device 11A of the active seat 11 to tilt the active seat 11 by the tilt angle θ2 calculated in step S204 (step S205). After that, the seat control ECU 20 ends the series of processes shown in FIG.

[0028] The seat control ECU 20 repeatedly executes the series of processes shown in FIG. 2 while the vehicle 10 is traveling.

[0029] (Calculation example of gain k) Fig. 3 is a diagram showing a class determination logic for determining the gain k by the seat control ECU 20 according to an embodiment. Fig. 4 is a graph showing a method for determining the gain k by the seat control ECU 20 according to an embodiment.

[0030] First, the gain determiner 22 of the seat control ECU 20 determines the class in accordance with the determination logic shown in Fig. 3. The determination logic shown in Fig. 3 includes "covered," "open eyes," and "gaze direction" as conditions related to the occupant's field of vision.

[0031] The gain determination unit 22 determines the class in accordance with the determination logic shown in FIG. 3 so that the higher the visibility of the occupant is determined to be, the higher the class is determined to be.

[0032] For example, when the gain determination unit 22 determines that the "cover" is "present," it determines the class as "Class 0." On the other hand, when the gain determination unit 22 determines that the "cover" is "not present," it determines the state as "open eyes."

[0033] If the gain determination unit 22 determines that "eyes open" is "NO", it determines the class as "Class 0." On the other hand, if the gain determination unit 22 determines that "eyes open" is "YES", it determines the "gaze direction."

[0034] When the gain determination unit 22 determines that the "gaze direction" is "toward the hand," it determines the class as "Class 1." When the gain determination unit 22 determines that the "gaze direction" is "forward," it determines the class as "Class 2."

[0035] For example, the gain determination unit 22 can determine each of "covered," "open eyes," and "direction of gaze" by analyzing an image of the occupant captured by a camera (not shown) mounted on the vehicle 10.

[0036] Alternatively, the gain determination unit 22 can determine each of "covered," "open eyes," and "direction of gaze" by displaying a setting screen for conditions related to the occupant's field of view on a display mounted on the vehicle 10 and having the occupant set conditions related to the field of view.

[0037] Subsequently, the gain determiner 22 of the seat control ECU 20 determines the gain k according to the graph shown in FIG.

[0038] For example, if the class is determined to be "Class 0," the gain determination unit 22 determines the gain k to be "1."

[0039] Furthermore, for example, if the class is determined to be "Class 1," the gain determining unit 22 determines the gain k to be "0.6."

[0040] Furthermore, for example, if the class is determined to be "Class 2," the gain determination unit 22 determines the gain k to be "0.2."

[0041] In this way, the seat control ECU 20 according to one embodiment increases the class and decreases the gain k as the visibility of the occupant is determined to be higher.

[0042] As a result, the seat control ECU 20 according to one embodiment reduces the tilt angle θ2 of the active seat 11 as the visibility of the occupant is determined to be higher, thereby suppressing the tilt of the occupant's field of view and thus suppressing any discomfort caused by the occupant's field of view. In this case, although the seat control ECU 20 according to one embodiment cannot completely cancel the gravitational acceleration G, canceling the gravitational acceleration G to some extent can reduce the physical burden on the occupant.

[0043] On the other hand, the seat control ECU 20 according to one embodiment can cancel the gravitational acceleration G more effectively and reduce the physical burden on the occupant by increasing the tilt angle θ2 of the active seat 11 as the visibility of the occupant is determined to be low. In this case, although the tilt of the occupant increases, the seat control ECU 20 according to one embodiment can suppress the discomfort caused by the occupant's field of view because the visibility of the occupant is low.

[0044] [First Modified Example] (Example of processing procedure by the seat control ECU 20) Fig. 5 is a flowchart showing an example of a procedure of processing by the seat control ECU 20 according to the first modified example. The example shown in Fig. 5 differs from the example shown in Fig. 2 in that in step S203, the gain determiner 22 determines the gain k depending on whether the vehicle 10 is in autonomous driving or not.

[0045] (Calculation example of gain k) Fig. 6 is a diagram showing a class determination logic for determining the gain k by the seat control ECU 20 according to the first modified example. Fig. 7 is a graph for determining the gain k by the seat control ECU 20 according to the first modified example.

[0046] First, the gain determination unit 22 of the seat control ECU 20 determines the class in accordance with the determination logic shown in Fig. 6. The determination logic shown in Fig. 6 includes "Autonomous driving in progress?" as a condition related to autonomous driving.

[0047] The gain determination unit 22 determines the class in accordance with the determination logic shown in FIG. 6 such that the lower the autonomous driving level of the vehicle 10, the higher the class.

[0048] For example, when the gain determination unit 22 determines that "Autonomous driving?" is "YES," it determines the vehicle to be "Class 0." On the other hand, when the gain determination unit 22 determines that "Autonomous driving?" is "NO," it determines the vehicle to be "Class 1."

[0049] Subsequently, the gain determiner 22 of the seat control ECU 20 determines the gain k in accordance with the graph shown in FIG.

[0050] For example, if the class is determined to be "Class 0," the gain determination unit 22 determines the gain k to be "1."

[0051] Also, for example, if the class is determined to be "Class 1," the gain determining unit 22 determines the gain k to be "0.2."

[0052] In this way, the seat control ECU 20 according to the first modification example sets the class higher and the gain k smaller as the autonomous driving level of the vehicle 10 becomes lower.

[0053] As a result, the seat control ECU 20 according to the first modification can reduce the influence of tilting the active seat 11 on driving operations, since the lower the autonomous driving level of the vehicle 10, the greater the amount of driving operations required by the occupant. In this case, although the seat control ECU 20 according to one embodiment cannot completely cancel out the gravitational acceleration G, canceling out the gravitational acceleration G to some extent can reduce the physical burden on the occupant.

[0054] On the other hand, the seat control ECU 20 according to the first modification can cancel the gravitational acceleration G more effectively and reduce the physical burden on the occupant by increasing the tilt angle θ2 of the active seat 11 as the autonomous driving level of the vehicle 10 increases. In this case, although the occupant's tilt increases, the seat control ECU 20 according to one embodiment can suppress the effect on driving operations caused by tilting the active seat 11 because the amount of driving operations by the occupant is small.

[0055] [Second Modification] (Example of processing procedure by the seat control ECU 20) Fig. 8 is a flowchart showing an example of a procedure of processing by the seat control ECU 20 according to the second modified example. The example shown in Fig. 8 differs from the example shown in Fig. 2 in that in step S203, the gain determiner 22 determines a gain k arbitrarily set by the occupant.

[0056] (Gain k setting example) FIG. 9 is a diagram showing an example of a setting screen for the gain k displayed by the seat control ECU 20 according to the second modification.

[0057] A setting screen 900 shown in FIG. 9 is displayed on a display provided in the vehicle 10 or a display provided in a mobile terminal carried by the occupant, and is used by the occupant to set the gain k.

[0058] 9, the occupant can switch the setting target of gain k between "roll" and "pitch." Also, the setting screen 900 allows the occupant to set "off," "weak," or "strong" for each of "roll" and "pitch."

[0059] For example, as shown in FIG. 9(a), when the occupant sets "OFF" on the setting screen 900, the gain determination unit 22 of the seat control ECU 20 determines "0" as the gain k.

[0060] Also, for example, as shown in FIG. 9(b), when the occupant sets "weak" on the setting screen 900, the gain determiner 22 of the seat control ECU 20 determines the gain k to be "0.5".

[0061] Also, for example, as shown in FIG. 9(c), when the occupant sets "strong" on the setting screen 900, the gain determiner 22 of the seat control ECU 20 determines "1" as the gain k.

[0062] In this way, the seat control ECU 20 according to the second modification determines the gain k in accordance with the setting on the setting screen 900 made by the occupant.

[0063] As a result, the seat control ECU 20 according to the second variant allows the occupant to set the optimal tilt angle of the active seat 11 for each situation (for example, when the eyes are closed, when working while looking at what is in front of them, when looking outside, etc.), thereby providing the occupant with a comfortable environment at all times.

[0064] In addition, the seat control ECU 20 according to the second variant allows multiple occupants to individually set the optimal inclination angle of the active seat 11, and can absorb individual differences in the inclination angle of the active seat 11 that they find comfortable, thereby providing a comfortable environment for multiple occupants.

[0065] The seat control ECU 20 according to the second modification may allow the occupant to select a continuous value as the gain k on the setting screen 900.

[0066] In addition, the seat control ECU 20 according to the second variant may store the gain k selected by the occupant in a memory unit for each individual occupant, and when the occupant gets in the vehicle, read out the gain k associated with that occupant from the memory unit and use it.

[0067] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0068] 10 vehicles 11 Active Seat 11A Seat drive unit 13 Vehicle control ECU 14 IMU 15 Battery 16 Motor generator 17 wheels 20 Seat control ECU 21 Angle calculation unit 22 Gain determination section 23 Seat tilt angle calculation unit 24 Seat control unit 900 Settings screen

Claims

1. an angle calculation unit that calculates an angle at which a resultant force of the vehicle acceleration and the gravitational acceleration becomes perpendicular to the seat surface; a seat inclination angle calculation unit that calculates an inclination angle of the seat by multiplying the angle calculated by the angle calculation unit by a gain that is changed under predetermined conditions; a seat control unit that tilts the seat to the tilt angle calculated by the seat tilt angle calculation unit; A seat control device for a vehicle, comprising:

2. The predetermined condition is a condition related to the visibility of the occupant, and the higher the visibility of the occupant is determined to be, the smaller the gain is set.

2. The vehicle seat control device according to claim 1.

3. The predetermined condition is a condition related to automatic driving, and the lower the automatic driving level, the smaller the gain is set.

2. The vehicle seat control device according to claim 1.

4. The predetermined conditions are arbitrarily set by the occupant.

2. The vehicle seat control device according to claim 1.

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