Sheet

Abstract

To provide a seat for easily obtaining an excellent body support state in response to a physique difference of a seated person.SOLUTION: A seat 1 having a seat surface part 10 and a seat back part 20 includes: support members 50 arranged in the seat back part so as to support predetermined sites of a body of a seated person and to be vertically movable; a support member drive part 51 for vertically driving the support members with respect to the seat back part; a specific side position estimation part for estimating the positions of the predetermined specific sites of the seated person; and a control part 90 for controlling the support member drive part so as to allow the support members to support the specific sites in response to the positions of the specific sites estimated by the specific site position estimation part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a seat that is installed in, for example, a vehicle and on which an occupant sits. [Background technology]

[0002] For example, in vehicle seats, it has been proposed to improve functionality by strengthening support for specific parts of the occupant's body (specific ribs, etc.). As a seat-related technology, for example, Patent Document 1 describes that in order to prevent posture from shifting left and right, a pair of horizontal scapular support ridges, which are arranged on either side of the widthwise centerline of the upper body support surface, are provided in the area facing the fifth to seventh ribs, and a rib support inclined ridge, which is inclined along the inclination of the ribs, is provided on the upper body support surface so as to abut between the ninth and tenth ribs, and the upper part of the upper body support surface above each ridge is movable up and down relative to the seat surface. Patent Document 2 describes that in order to reduce the deterioration of the seated posture throughout the body, the peak load position of the pelvis is detected in the seat cushion, and the position of the shoulder blades is detected from the load distribution of the thorax detected in the seat back, and the seating part and seat back are displaced in a direction that eliminates deviation of each position from its initial position. Patent document 3 describes a system in which an imaging device and a non-contact human presence sensor installed inside the vehicle detect the position of the occupant's head and the contact position between the shoulder blades and the seat back, and a body pressure sensor built into the seat cushion detects body pressure in the thighs, etc., to determine the occupant's physique. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-45098 A [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-165588 [Patent Document 3] JP 2016-37107 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, in order to improve ease of various operations such as driving operations and ride comfort, it is required to suppress the roll behavior of the occupant's body caused by input from the road surface and lateral acceleration while driving. It is known that strengthening support for specific ribs, as in the technology described in Patent Document 1, can prevent the body from collapsing to the left or right. However, because there are individual differences (variations) in the position (especially height) of occupants' ribs, in order to accommodate a wide range of body types, it is necessary to provide an adjustment mechanism for the rib support member. However, adjusting the rib support members by the occupant themselves is a complicated operation, and if the occupant has little knowledge of the anatomy, it can be difficult to adjust the support members to the correct position to support a specific rib. In view of the above-mentioned problems, an object of the present invention is to provide a seat that can easily provide good body support according to differences in the physique of seated occupants. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a seat according to one aspect of the present invention is a seat having a seat surface portion and a seat back portion, and including: a support member provided on the seat back portion, which supports a predetermined part of the body of a seated occupant and is movable in an up-down direction; a support member drive unit which drives the support member in the up-down direction relative to the seat back portion; a specific part position estimation unit which estimates the position of the predetermined specific part of the seated occupant; and a control unit which controls the support member drive unit so that the support member supports the specific part according to the position of the specific part estimated by the specific part position estimation unit. a surface pressure distribution detection unit provided in the seat back portion and detecting a distribution of surface pressure received from the back of the seated occupant; Equipped with The specific body part position estimation unit detects the positions of a first reference point set on the upper part of the upper body of the seated person and a second reference point set on the lower back of the seated person based on the distribution of the surface pressure detected by the surface pressure distribution detection unit, estimates the position of the specific body part by dividing the distance between the first reference point and the second reference point at a predetermined ratio, and performs image processing to detect the positions of the first reference point and a third reference point set on the upper part of the upper body of the seated person and different from the first reference point based on an image captured by an imaging unit that captures an image of the seated person. and a seating state abnormality detection unit that detects an abnormality in the seating state of the seated occupant when a position of the first reference point detected by the image processing unit and a position of the first reference point detected based on the distribution of the surface pressure deviate by a predetermined amount or more, and when a distance between the first reference point detected by the image processing unit and the third reference point and a distance between the first reference point detected based on the distribution of the surface pressure deviate by a predetermined amount or more, wherein the distance between the first reference point and the third reference point is a size of the shoulder blades of the seated occupant. It is characterized by: With this, the position of a specific part of the occupant's body that should be supported is estimated by the specific part position estimation unit, and by controlling the support member drive unit according to the estimation result, it is possible to automatically position the support member in a position that supports the specific part, making it possible to easily support the specific part without forcing the occupant to perform complicated operations, and achieving a good body support state. Furthermore, this allows the physique of the seated occupant to be recognized with high accuracy according to the distribution of surface pressure (body pressure), and the position of a specific part to be accurately estimated according to the recognized physique. Furthermore, this makes it possible to easily estimate the position of the specific part with a light calculation load based on the positions of the first and second reference points. Here, the predetermined ratio may be, for example, a known value obtained statistically. This also makes it possible to prevent the support member from being positioned inappropriately when the seated posture of the seated person becomes unstable.

[0009] In the present invention, the specific part may be the ninth rib of the seated occupant. This reduces the rolling motion of the seated occupant's body, making it easier to perform various operations such as driving, and improving ride comfort. [Effects of the Invention]

[0010] As described above, according to the present invention, it is possible to provide a seat that can easily provide a good body support state according to differences in the physique of seated occupants. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic side view of an embodiment of a seat to which the present invention is applied. [Figure 2] FIG. 2 is a view taken along the line II-II in FIG. [Figure 3] FIG. 2 is a block diagram illustrating a configuration of a control system in the seat according to the embodiment. [Figure 4] 6 is a flowchart illustrating drive control of a support member in the seat according to the embodiment. [Figure 5] 10A and 10B are diagrams illustrating an example of a detection result of a surface pressure measuring unit in the seat of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of a seat to which the present invention is applied will be described. The seat of the embodiment is used as a front seat (driver's seat, passenger seat) of an automobile such as a passenger car, for example. FIG. 1 is a schematic side view of a seat according to an embodiment. Fig. 2 is a view taken along the line II-II in Fig. 1. Note that in Fig. 2, the seated person is not shown.

[0013] The seat 1 of the embodiment is configured to include a seating surface portion 10, a seat back 20, a headrest 30, a surface pressure measuring portion 40, a support member 50, and the like. The seat surface 10 is a portion on which the buttocks 110 and thighs 120 of the seated occupant 100 rest. The seat back 20 is a backrest-like portion arranged along the back 131 of the upper body 130 of the occupant 100. The seat back 20 is formed to extend upward from the vicinity of the rear end of the seat cushion portion 10. The headrest 30 is provided to protrude upward from the upper end of the seat back 20 and is a portion that supports the rear of the head 140 of the occupant 100.

[0014] The surface pressure measuring unit 40 is provided on the surface of the seat back 20 that comes into contact with the back 131 of the occupant 100, and measures the distribution of surface pressure (body pressure) that the seat back 20 receives from the back 131. The surface pressure measuring unit 40 can be configured, for example, by arranging pressure-sensitive elements such as pressure-sensitive conductive ink electrode pairs, whose resistance value changes depending on the pressure received, in a matrix along the surface direction of a film-like sensor sheet.

[0015] The support member 50 is a member that supports a specific part of the body of the occupant 100, for example, the lower part of the ninth rib. The support member 50 is provided along a surface portion facing the back portion 131 of the seat back 20, and is formed as, for example, a rod-shaped elongated member from a material harder than the other portions of the seat back 20 (cushion, etc.). The support members 50 are provided, for example, in pairs, symmetrically about the center line of the seat back 20 in the left-right direction. The support member 50 is arranged with its longitudinal direction tilted so that the outer sides in the left-right direction are lower than the center part in order to match the inclination of the ribs.

[0016] The support member 50 is typically positioned to support the ninth rib of the occupant 100 from below. The support member 50 is attached to the seat back 20 so as to be movable in the up and down direction relative to the seat back 20 in order to accommodate individual differences in the physique of the occupant 100 . The support member 50 is provided with a support member driving actuator 51 (see FIGS. 2 and 3). The support member driving actuator 51 drives and moves the support member 50 in the up and down direction along the seat back 20 . The support member drive actuator 51 can be configured as an electric actuator having, for example, an electric motor and a reduction gear train, but is not limited to this and other types of actuators may also be used. In this embodiment, the height of the ninth rib is estimated by acquiring information about the physique of the occupant 100, and the height of the support member 50 is automatically adjusted by the support member driving actuator 51. This point will be explained in more detail later.

[0017] Furthermore, a camera 70 is provided on an instrument panel 60, which is an interior member of the vehicle and is arranged opposite the seat 1. The camera 70 includes, for example, a solid-state image pickup device such as a CMOS or a CCD, an output processing circuit for the image pickup device, an image pickup optical system (lens group), and the like. The camera 70 captures an image of the occupant 100 seated in the seat 1, and transmits the obtained image data to a driver monitoring system 80, which will be described later.

[0018] FIG. 3 is a block diagram that schematically shows the configuration of a control system in the seat of the embodiment. The control system of the seat 1 includes the above-mentioned surface pressure measuring unit 40, a driver monitoring system 80, a seat control unit 90, a support member driving actuator 51, and the like.

[0019] The driver monitoring system 80 is an image processing device that identifies the occupant (driver) 100 seated in the seat 1 by facial recognition and acquires information about the physique based on an image captured by the camera 70. The driver monitoring system 80 has a function of determining the height position of the first thoracic vertebra present in the upper part of the shoulder of the occupant 100 (near the upper end of the upper body 130), for example.

[0020] The seat control unit 90 controls the support member driving actuator 51 based on information from the surface pressure measuring unit 40 and the driver monitoring system 80 . The seat control unit 90 can be configured as a microcomputer having, for example, an information processing unit such as a CPU, a recording unit such as a RAM or a ROM, an input / output interface, and a bus connecting these. The seat control unit 90 functions as a specific body part position estimation unit, a control unit, and an abnormal seating state detection unit of the present invention. The function and operation of the seat control unit 90 will be explained in detail later.

[0021] Next, the drive control of the support member 50 in the seat of this embodiment will be described. FIG. 4 is a flowchart showing drive control of the support member in the seat according to the embodiment. Each step will be explained in order below.

[0022] <Step S01: Detecting the position of the first thoracic vertebra from surface pressure> Based on the output of the surface pressure measuring section 40, the seat control unit 90 detects the position of the first thoracic vertebra of the occupant 100 in the height direction (typically, the distance from the hip point of the seating surface 10). FIG. 5 is a diagram showing an example of a detection result of a surface pressure measuring unit in the seat of the embodiment. In FIG. 5, the vertical axis indicates the distance from the hip point, and the vertical axis indicates the surface pressure (higher on the right side). The highest peak in the surface pressure (body pressure) distribution is thought to indicate the position of the first thoracic vertebra. For example, in the example shown in FIG. 5, the first thoracic vertebra is thought to be located at a position of approximately 430 mm. Then, proceed to step S02.

[0023] <Step S02: Detecting the position of the first thoracic vertebra from the image> The driver monitoring system 80 performs image processing on the image data captured by the camera 70 to detect the height of the first thoracic vertebra of the occupant 100. The detected height of the first thoracic vertebra is transmitted to the seat control unit 90. Then, proceed to step S03.

[0024] <Step S03: First thoracic vertebra position agreement determination> The seat control unit 90 determines whether or not the position of the first thoracic vertebra detected from the surface pressure in step S01 substantially matches the position of the first thoracic vertebra detected from the image in step S02. For example, if the absolute value of the difference between the detected values ​​is equal to or less than a preset threshold, it is determined that the values ​​substantially match and the process proceeds to step S04; otherwise, it is determined that the values ​​do not match and the process proceeds to step S06.

[0025] <Step S04: Detecting the distance between the first thoracic vertebra and the third lumbar vertebra> The seat control unit 90 detects the distance from the first thoracic vertebra (first reference point) to the third lumbar vertebra (second reference point) of the occupant 100 based on the output of the surface pressure measuring section 40. As shown in Figure 5, in the distribution of surface pressure (body pressure), a drop in surface pressure is observed at a height of 215 to 220 mm from the hip point. The height of the area where the surface pressure is reduced is thought to indicate the height of the third lumbar vertebra. Then, proceed to step S05.

[0026] <Step S05: Calculating the position of the 9th thoracic vertebra> The seat control unit 90 calculates the position of the ninth thoracic vertebra of the occupant 100 using the following equation 1. Here, the position of the ninth thoracic vertebra is considered to substantially coincide with the position of the ninth rib, which is a specific site in the embodiment. (1st to 9th thoracic vertebrae) = (height of the first thoracic vertebra to the third lumbar vertebra) / (statistical mean value of height of the first thoracic vertebra to the third lumbar vertebra) × (Statistical mean value of the height of the first to ninth thoracic vertebrae) (Equation 1) After calculating the position of the ninth thoracic vertebra, the process proceeds to step S10.

[0027] <Step S06: Detecting the distance between the first thoracic vertebra and the third lumbar vertebra> The seat control unit 90 detects the distance from the first thoracic vertebra to the third lumbar vertebra of the occupant 100 based on the output of the surface pressure measuring unit 40. Then, proceed to step S07.

[0028] <Step S07: Seating posture determination> The seat control unit 90 uses the following equation 2 to determine whether or not the shoulder blades (first to seventh thoracic vertebrae) of the occupant 100 can be recognized based on the output of the surface pressure measuring unit 40. {(height of the first thoracic vertebra to the seventh thoracic vertebra) / (statistical average height of the first thoracic vertebra to the seventh thoracic vertebra)} -{(height of the first thoracic vertebra to the third lumbar vertebra) / (statistical average value of height of the first thoracic vertebra to the third lumbar vertebra)} ...(Formula 2) Each statistical average value can be stored in advance in a recording section of the seat control unit 90. Thereafter, if the seat control unit 90 is able to recognize the size of the shoulder blades (the distance from the first thoracic vertebra to the seventh thoracic vertebra), and the difference between the size of the shoulder blades estimated from the physique of the occupant 100 recognized by, for example, the driver monitoring system 80 and the size of the shoulder blades calculated from Equation 2 is within a predetermined threshold (for example, within plus or minus 5%), it determines that the size of the shoulder blades is appropriate for the physique of the occupant 100, and the seating posture of the occupant 100 is normal, and proceeds to step S08; otherwise, it determines that the seating posture of the occupant 100 is abnormal, and proceeds to step S09.

[0029] <Step S08: Calculating the position of the 9th thoracic vertebra> The seat control unit 90 calculates the position of the ninth thoracic vertebra of the occupant 100 using Equation 1 above. After calculating the position of the ninth thoracic vertebra, the process proceeds to step S10.

[0030] <Step S09: Alert output> The seat control unit 90 determines that the seating position of the occupant 100 is abnormal and that the support member 50 cannot be properly adjusted, and outputs an alert to the occupant 100, for example, via a warning light, image display device, audio output device, etc. (not shown), instructing the occupant 100 to correct his or her seating position. Furthermore, if the seat 1 is a so-called power seat that can adjust the forward / backward sliding, tilt, and elevation of the seat portion 10, and the tilt of the seat back 20, for example, using an electric actuator, the state of the seat 1 may be changed so as to correct the posture of the occupant 100. After that, the series of processes ends (returns).

[0031] <Step S10: Support Member Position Control> Based on the position of the ninth thoracic vertebra calculated in step S05 or step S08, the seat control unit 90 issues a command to the support member drive actuator 51 to adjust the position (height) of the support member 50 so as to be able to support the ninth rib, which is located at approximately the same height. After that, the series of processes ends (returns).

[0032] As described above, according to this embodiment, the following effects can be obtained. (1) The seat control unit 90 calculates (estimates) the position of the ninth rib, which is a specific part of the occupant's 100 body that should be strengthened in support, and controls the support member actuator 51 according to the estimation result, thereby enabling the support member 50 to be automatically positioned to support the ninth rib. This makes it possible to easily support the ninth rib without forcing the occupant 100 to perform complicated operations, thereby achieving a good body support state. (2) By calculating the position of the ninth rib based on the output of the surface pressure measuring unit 40, the position of the ninth rib can be accurately estimated. (3) Based on the distribution of surface pressure, the position of the first thoracic vertebra, which is the first reference point set on the upper part of the upper body 130 of the occupant 100, and the position of the third lumbar vertebra, which is the second reference point set on the lumbar region of the occupant 100, are detected, and the position of the ninth rib is estimated by dividing the distance between the first thoracic vertebra and the third lumbar vertebra internally at a predetermined ratio obtained statistically. This makes it possible to easily estimate the position of the ninth rib with a light computational load. (4) When the position of the first thoracic vertebra detected by the driver monitoring system 80 differs from the position of the first thoracic vertebra detected based on the distribution of surface pressure by a predetermined amount or more, an abnormality in the seating position of the occupant 100 is detected, thereby preventing the position of the support member 50 from being set inappropriately when the seating posture of the occupant 100 becomes unstable. (5) By supporting the ninth rib, the support member 50 suppresses the rolling behavior of the body of the occupant 100, particularly the upper body 130 and head 140, thereby improving the ease of various operations such as driving and the ride comfort.

[0033] (Variation) The present invention is not limited to the above-described embodiment, and various modifications and variations are possible, and these are also within the technical scope of the present invention. (1) The configurations of the seat, control system, vehicle, etc. are not limited to the above-described embodiment and can be modified as appropriate. For example, the configuration of each of these constituent elements and members can be changed as appropriate. (2) In the embodiment, the support member is configured to support the ninth rib, but this is not limited to this, and the present invention can also be applied to cases where support for other specific parts of the occupant's body (e.g., other ribs, lumbar vertebrae, etc.) is to be strengthened. (3) In the embodiment, the front seat of a passenger car is described as an example, but the present invention is not limited to this. For example, the present invention can also be applied to seats in the second row or later of a passenger car, or seats of other vehicle types, car shapes, railway vehicles, etc. Furthermore, the present invention is not limited to applications in vehicles, but can also be applied to various types of seats in vehicles other than vehicles, such as aircraft and ships, as well as in homes, offices, theaters, restaurants, and the like. [Explanation of symbols]

[0034] 1 seat 10 seating surface 20 Seat back 30 Headrest 40 surface pressure measuring unit 50 support member 51 support member drive actuator 60 instrument panel 70 Camera 80 Driver Monitoring System 90 Seat Control Unit 100 Seated person 110 Buttocks 120 Thigh 130 Upper body 140 Head

Claims

1. A seat having a seat cushion and a seat back, a support member provided in the seat back portion, supporting a predetermined part of the body of a seated occupant and movable in the up and down direction; a support member driving unit that drives the support member in a vertical direction relative to the seat back portion; a specific body part position estimation unit that estimates the position of a predetermined specific body part of the seated occupant; a control unit that controls the support member driving unit so that the support member supports the specific part according to the position of the specific part estimated by the specific part position estimation unit; a surface pressure distribution detection unit provided in the seat back portion and detecting a distribution of surface pressure received from the back of the seated occupant; Equipped with the specific body part position estimation unit detects the positions of a first reference point set on an upper part of the upper body of the seated occupant and a second reference point set on a lower back of the seated occupant based on the distribution of the surface pressure detected by the surface pressure distribution detection unit, and estimates the position of the specific body part by dividing the distance between the first reference point and the second reference point internally at a predetermined ratio; an image processing unit that detects the positions of the first reference point and a third reference point that is set at an upper part of the upper body of the seated occupant and is different from the first reference point, based on an image captured by an imaging unit that captures an image of the seated occupant; a seating state abnormality detection unit that detects an abnormality in the seating state of the seated person when a position of the first reference point detected by the image processing unit and a position of the first reference point detected based on the distribution of the surface pressure deviate by a predetermined amount or more, and when a distance between the first reference point detected by the image processing unit and the third reference point and a distance between the first reference point detected based on the distribution of the surface pressure deviate by a predetermined amount or more, The distance between the first reference point and the third reference point is the size of the shoulder blades of the seated occupant. A seat characterized by:

2. The specific part is the ninth rib of the seated person. The sheet according to claim 1, characterized in that

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