United States Patent [i9]
`United States Patent [191
`Cashier
`Cashler
`
`Hiiainiiiiniiiiiii!
`llllllllllllllllllllllllllllllllllllllllllllllllll|||l||l|||l|||ll|
`US005732375A
`USOO5732375A
`[ii] Patent Number:
`5,732,375
`5,732,375
`[11] Patent Number:
`Mar. 24, 1998
`[45] Date of Patent:
`Mar. 24, 1998
`[45] Date of Patent:
`
`[54] METHOD OF INHIBITING OR ALLOWING
`[54] METHOD OF INHIBITING OR ALLOWING
`AIRBAG DEPLOYMENT
`AIRBAG DEPLOYMENT
`Inventor: Robert John Cashier, Kokomo, Ind.
`[75]
`[75] Inventor: Robert John Cashler, Kokomo, Ind.
`[73] Assignee: Delco Electronics Corp., Kokomo, Ind.
`[73] Assignee: Delco Electronics Corp., Kokomo, Ind.
`
`[21] Appl. No.: 566,029
`[21] App1.No.: 566,029
`Dec. 1, 1995
`[22] Filed:
`[22] Filed:
`Dec. 1, 1995
`B60R 21/32; G06F 17/40
`[51] Int CL6
`[51] Im. GL6 ........................... .. B60R 21/32; G06F 17/40
`701/45; 701/46; 180/273;
`[52] US. Cl. ............................ .. 701/45; 701/46; 180/273;
`[52] U.S. CL
`280/735
`280/735
`[58] Field of Search ................... .. 364/424.055. 424.056,
`364/424.055, 424.056.
`[58] Field of Search
`364/424.057, 567,568; 180/271, 282. 268,
`364/424.057, 567. 568; 180/271, 282, 268,
`273; 307/151; 340/436, 438; 280/735,
`273; 307/15.1; 340/436, 438; 280/735,
`730.01, 730.02
`730.01, 730.02
`
`[56]
`[56]
`
`References Cited
`References Cited
`U.S. PATENT DOCUMENTS
`U.S. PATENT DOCUMENTS
`5,010,774
`4/1991 Kiko et a1. ....................... .. 73/862042
`4/1991 Kiko et al
`73/862.042
`5,010,774
`
`
`5,161,820 11/1992 Vollmer ....... .. 5,232,243 8/1993 Blackburn et a1.
`11/1992 Vollmer
`. 280/730.1
`5,161,820
`.... 280/732
`8/1993 Blackburn et al.
`.
`1/1995 Araki et a1. ...... ..
`5,384,716
`5,232,243
`5,454,591 10/1995 Mazur et al. ......................... .. 280/735
`1/1995 Araki et al
`.... 364/557
`5,384,716
`10/1995 Mazur et al
`.... 280/735
`5,454,591
`
`180/268
`12/1995 Schousek
`5,474,327
`5,474,327 12/1995 Schousek .............................. .. 180/268
`280/735
`2/1996 Blackburn et al
`5,494,311
`5,494,311
`211996 Blackburn et a1.
`.. 280/735
`364/559
`10/1996 Barrus
`5,570,301
`5,570,301 10/1996 Barrus ............ ..
`364/559
`280/735
`11/1996 Meister et al
`5,570,903
`5,570,903 11/1996 Meister et a1.
`.. 2801735
`280/735
`2/1997 Blackburn et al
`5,605,348
`5,605,348
`2/1997 Blackburn et a1.
`..... .. 280/7 35
`3/1997 Zeidler et al
`364/424.055
`5,612,876
`5,612,876
`3/1997 Zeidler et al. ................. .. 364/424055
`OTHER PUBLICATIONS
`OTHER PUBLICATIONS
`Research Disclosure—Jan. 1994 #357—"Method for Sens­
`Research Disc1osure—]an. 1994 #3S7-—“Method for Sens
`ing Occupant Mass and Position.” Disclosed Anonymously.
`ing Occupant Mass and Position." Disclosed Anonymously.
`Primary Examiner—Tan Q. Nguyen
`Primary Examiner—Tan Q. Nguyen
`Attorney, Agent, or Fim1—-Mark A. Navarre
`Attorney, Agent, or Firm—Mark A. Navarre
`[57]
`ABSTRACT
`ABSTRACT
`[57]
`An array of pressure sensors on a vehicle passenger seat
`An array of pressure sensors on a vehicle passenger seat
`senses the presence of an occupant including an infant seat
`senses the presence of an occupant including an infant seat
`and determines whether the infant seat faces forward or
`and determines whether the infant seat faces forward or
`rearward. A microprocessor coupled to the sensors deter
`rearward. A microprocessor coupled to the sensors deter­
`mines whether to allow or inhibit deployment based on the
`mines whether to allow or inhibit deployment based on the
`sensor load forces and the pattern of loading. The pattern can
`sensor load forces and the pattern of loading. The pattern can
`identify an infant seat and pattern and loading determine its
`identify an infant seat and pattern and loading determine its
`orientation. Local areas are checked to detect child occu
`orientation. Local areas are checked to detect child occu­
`pants. Fuzzy logic is used to determine loading and to
`recognize patterns.
`pants. Fuzzy logic is used to determine loading and to
`recognize patterns.
`19 Claims, 4 Drawing Sheets
`19 Claims, 4 Drawing Sheets
`
`FORWARD
`
`( DECISION
`RAILS DETECTED
`>™<
`N
`O
`7^ 62
`RAILS DETECTED
`INFANT SEAT TYPE
`REAR @
`TOTAL FORCE
`NO
`LO >
`ALLOW
`
`60
`58
`
`H]
`
`68
`
`HI
`H]
`
`I
`
`TOTAL FORCE
`LOCALIZED FORCE
`AND FLAG
`
`42
`
`YES
`
`FORWARD ,
`
`N
`INHIBIT )
`62
`INFANT SEAT TYPE
`
`LO
`
`7O
`
`70
`
`7 2
`
`REAR v-
`
`LOCALIZED FORCE
`AND FLAG
`TOTAL LOAD RATING
`
`72
`
`Hl
`
`LO
`TOTAL LOAD RATING
`FRONT FORCE & ALL FRONT FLAG
`
`Hi
`FRONT FORCE & ALL FRONT FLAG
`LEFT FORCE 81 ALL LEFT FLAG
`
`1*"
`
`LEFT FORCE & ALL LEFT FLAG
`RIGHT FORCE 81 ALL RIGHT FLAG
`
`74
`
`74
`75
`
`76
`7a
`
`HI
`REAR FORCE 81 ALL HEAR FLAG
`RIGHT FORCE & ALL RIGHT FLAG
`
`78
`8o
`
`HI
`
`CENTER GROUP FORCE
`REAR FORCE & ALL REAR FLAG
`
`52
`80
`
`84
`HI‘
`TOTAL FUZZY VALUE 5 v
`CENTER GROUP FORCE
`
`X
`
`82
`
`( ALLOW )
`
`I INHIBIT i
`TOTAL FUZZY VALUE
`
`84
`
`( ALLOW )
`
`(INHIBIT)
`
`Aisin Seiki Exhibit 1008
` Page 1
`
`

`
`U.S. Patent
`U.S. Patent
`
`Sheet 1 of 4
`Mar. 24, 1998
`Mar. 24, 1998
`Sheet 1 0f 4
`FIG - 1
`FIG - 1
`
`5,732,375
`5,732,375
`
`15
`15
`
`.
`
`‘
`
`18X
`18
`AIR BAG
`DEPLOYMENT
`AIR BAG
`DEPLOYMENT
`-
`
`13__/
`13
`
`24
`24
`30 28 i. 26
`16
`MV ‘,
`ACCELEROMETER ——> \) _
`ACCELEROMETER
`cc
`C:
`CC
`'
`0 DECISION‘ O L‘VQVQ
`DC
`DECISION
`O
`O
`7
`w
`a
`w
`20
`CO
`w
`20
`w
`a
`|
`w
`\
`CO
`LU
`.
`Hi
`o
`o
`8
`32
`|
`o
`o
`32
`O
`FAULTINDICATOR -——— n:
`-
`2 3O
`FAULT INDICATOR
`DC
`g
`!
`[L
`30
`CC
`Q_
`o
`CL
`0:
`FAULT 1
`2
`3o
`O
`FAULT
`^-30
`DC
`o
`CC
`95’
`z
`i
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`o
`7
`34
`i
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`2
`2
`34
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`!
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`.
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`.
`
`9 +5V
`T+5V
`
`30 28
`
`•
`
`26' '
`26 •
`'
`28
`25'
`r26
`
`/A—,
`
`23
`
`? 22
`
`22
`
`28
`26 "
`26
`28
`\
`i
`V
`' SEAT OCCUPANT
`14
`SIR MODULE
`DETECTOR
`SIR MODULE i SEAT OCCUPANT
`|
`14
`DETECT0R
`I
`
`FIG - 2
`FIG - 2
`
`5 1o 15 2o 25 30 35404
`5-.
`IE]
`El
`5 10 15 20 25 30 35 40 45
`H
`h
`
`+ E
`
`m
`
`10-
`15" [II
`1 0 -
`20 -—
`m
`m
`1 5 -
`25“
`E El
`[I] [U
`2 0 -
`30-5
`IE
`El E1
`E]
`25 --
`[U B 0 0
`35--
`E]
`E
`3 0 - -
`[1]
`0
`
`IE]
`
`40 ~
`
`35 -
`4 0 -
`
`Aisin Seiki Exhibit 1008
` Page 2
`
`

`
`(M
`<1
`(jJ
`
`<1
`Lh
`
`MS
`o
`to
`rt> re
`CO er
`
`ac
`"O
`vo
`4^.
`S3 r<
`2
`
`9
`ft
`P
`hd
`
`a xn
`
`58
`
`^r56
`
`^-54
`
`52
`
`50
`
`40
`
`• FUZZY CONTR.
`• TOTAL LOAD RATING
`
`COMPUTE
`
`DETERMINE EACH LOAD RATING
`
`• COMPUTE FUZZY CONTR.
`
`I
`i
`i
`
`CHECK FOR LOCALIZED AREA
`
`C TO DECISION ALGORITHM
`
`I
`
`• CENTER FOUR
`• LEFT PAIR
`• RIGHT PAIR
`• REAR PAIR
`• FRONT PAIR
`
`FUZZY CONTR. FOR
`COMPUTE FORCEAND
`
`I
`
`• ALL REAR
`• ALL RIGHT
`• ALL LEFT
`• ALL FRONT
`SET FLAG FOR
`
`40
`
`38
`
`ALLOW LIGHT
`
`TURN ON
`
`48
`
`ALLOW
`
`44
`
`42
`
`INHIBIT LIGHT
`
`TURN ON
`
`11
`
`46
`
`DECISION
`
`INHIBIT
`
`Aisin Seiki Exhibit 1008
` Page 3
`
`ALGORITHMS
`RUN DECISION
`
`1
`I
`
`COMPUTE ALL DECISION
`FROM FILTERED DATA
`
`MEASURES
`
`THE DATA
`
`ADJUST DATA WITH BIAS
`
`AND LOWPASS FILTER
`
`C COMPUTE DECISON MEASURES
`
`OF SENSOR VALUES
`TOTAL FORCE = SUM
`
`i
`
`FIG-4
`
`36
`
`.VALUES
`SENSOR
`INPUT 12
`
`FIG-3
`
`

`
`U.S. Patent
`US. Patent
`
`Mar. 24, 1998
`Mar. 24, 1998
`
`Sheet 3 of 4
`Sheet 3 0f 4
`
`5,732,375
`5,732,375
`
`i i
`
`FORCE OR LOAD
`
`FORCE OR LOAD FUZZY
`FUZZY
`CONTRIBUTION
`CONTRIBUTION
`F I G - 5
`5
`
`-
`
`i i
`4
`4
`
`LOAD RATING
`LOAD RATING
`
`FIG - 6
`F I G - 6
`
`0
`
`b
`
`i
`
`d
`
`.
`;
`z
`c
`c
`
`D’
`FORCE
`FORCE
`OR LOAD
`OR LOAD
`
`LOAD
`
`51015 20 25 30 3540 45
`5 10 15 20 25 30 35 40 45
`M
`
`6 1 /
`
`0
`
`~
`
`\ '
`
`r
`
`5 -
`
`10 __
`
`*
`'
`3'2,» FRONT
`\
`* :
`\ff-^ FRONT
`z-VLEFT
`mii
`LEFT
`[Eli/“RIGHT
`'--RIGHT
`1
`_t
`N
`r - '
`E]
`REAR
`REAR
`
`/
`
`I
`I
`
`1 0 - -
`15 -_
`..m
`15 -•
`F|G .. 7 20
`i® a
`F I G - 7 2 0 - N
`2s --
`30 _
`25 --
`HI iE [U 03
`30 --
`Jm
`35 --
`E\
`35 --
`40 --
`^
`^ Js
`FIG-9 @
`F I G - 9
`62
`
`I‘
`
`40 -
`
`0
`
`SEATTYPE )
`
`64
`
`66
`
`—TOTAL^
`FORCE > X
`
`YES
`
`FRONT PAIR LOADED !
`
`NO
`AND TOTAL FORCE > Y
`
`(^INHIBIT
`
`N0/ FRONT PAIR LOADED \YE§
`\ AND TOTAL FORCE > Y / ^
`
`ALLOW )
`
`Aisin Seiki Exhibit 1008
` Page 4
`
`

`
`U.S. Patent
`US. Patent
`
`Mar. 24, 1998
`Mar. 24, 1998
`
`5,732,375
`5,732,375
`
`Sheet 4 of 4
`Sheet 4 0f 4
`42
`42
`
`FORWARD /
`FORWARD
`—a-f
`
`INHIBIT J
`
`( DECISION
`
`RAILS DETECTED
`
`YES
`
`INFANT SEAT TYPE
`
`62
`
`NO
`
`TOTAL FORCE
`
`LO >
`
`70
`
`ALLOW
`
`REAR
`
`I
`\
`\
`
`60
`
`68
`
`HI
`
`HI
`
`HI
`
`LOCALIZED FORCE
`LOCALIZED FORCE
`AND FLAG
`AND FLAG
`
`III
`
`72
`72
`TOTAL LOAD RATING \5 LO
`LO v
`/
`TOTAL LOAD RATING
`I
`\
`14
`74
`FROM FORGE & ALL FRoNT FLAGYJ
`HI
`<^FRONT FORCES ALL FRONT FLAG
`Y
`I
`1
`I
`I
`HI 1
`HI <
`I
`I
`CENTER GRouP FoRcE>’\’a2
`HI <
`82
`I
`
`Hl
`HI
`
`76
`LEFT FoRcE & ALL LEFT FLAG >’\/
`76
`LEFT FORCE & ALL LEFT FLAG
`
`HI
`
`RIGHT FORCE &ALL RIGHT FLAG?’ 78
`HI
`78
`/RIGHT FORCE & ALL RIGHT FLAG
`
`REAR FoRcE &ALL REAR FLAG>’\-' 8°
`80
`
`REAR FORCE & ALL REAR FLAG
`
`CENTER GROUP FORCE
`
`H'
`
`84
`'
`TOTAL FUZZY VALUE ' S V
`
`HI
`^ TOTAL FUZZY VALUE
`4
`
`84
`
`U
`ALLOW
`( INHIBIT )
`Q ALLOW )
`
`INHIBIT^)
`
`FIG-8
`
`F I G - 8
`
`Aisin Seiki Exhibit 1008
` Page 5
`
`

`
`5,732,375
`5 ,732,375
`2
`1
`2
`1
`sample each sensor, determine a total weight parameter by
`METHOD OF INHIBITING OR ALLOWING
`sample each sensor, determine a total weight parameter by
`summing the pressures, and determine the pattern of pres­
`METHOD OF INHIBITING OR ALLOWING
`AIRBAG DEPLOYMENT
`summing the pressures, and determine the pattern of pres
`AIRBAG DEPLOYMENT
`sure distribution by evaluating local groups of sensors.
`sure distribution by evaluating local groups of sensors.
`Total force is sufficient for proper detection of adults in
`Total force is su?icient for proper detection of adults in
`FIELD OF THE INVENTION
`5 the seat, but the pattern recognition provides improved
`the seat, but the pattern recognition provides improved
`FIELD OF THE INVENTION
`detection of small children and infant seats. To detect infant
`This invention relates to occupant restraints for vehicles
`detection of small children and infant seats. To detect infant
`This invention relates to occupant restraints for vehicles
`seats, all patterns of sensor loading which correspond to the
`and particularly to a method using seat sensors to determine
`seats, all patterns of sensor loading which correspond to the
`and particularly to a method using seat sensors to determine
`imprints of various seats are stored in a table and the
`imprints of various seats are stored in a table and the
`seat occupancy for control of airbag deployment.
`seat occupancy for control of airbag deployment.
`detected sensor pattern is compared to the table entries.
`detected sensor pattern is compared to the table entries.
`10 Front and rear facing seats are discriminated on the basis of
`10
`Front and rear facing seats are discriminated on the basis of
`BACKGROUND OF THE INVENTION
`BACKGROUND OF THE INVENTION
`total force and the loading of sensors in the front of the seat.
`total force and the loading of sensors in the front of the seat.
`The expanding use of supplemental inflatable restraints
`The expanding use of supplemental in?atable restraints
`The pattern recognition for detecting children is made
`The pattern recognition for detecting children is made
`(SIRs) or airbags for occupant protection in vehicles increas­
`(SIRs) or airbags for occupant protection in vehicles increas
`possible by applying fuzzy logic concepts to the pressure
`possible by applying fuzzy logic concepts to the pressure
`ingly involves equipment for the ?ont outboard passenger
`ingly involves equipment for the front outboard passenger
`readings for each sensor in the array and assigning a load
`readings for each sensor in the array and assigning a load
`seat. The driver side airbag has been deployed whenever an
`15
`seat. The driver side airbag has been deployed whenever an 15
`rating to each sensor. Pattern recognition is also enhanced by
`rating to each sensor. Pattern recognition is also enhanced by
`imminent crash is sensed The position and size of the driver
`sampling several pairs of sensors, applying leveling tech
`imminent crash is sensed. The position and size of the driver
`sampling several pairs of sensors, applying leveling tech­
`is fairly predictable so that such deployment can advanta
`is fairly predictable so that such deployment can advanta­
`nique to them, and computing a measure for the area of the
`nique to them, and computing a measure for the area of the
`geously interact with the driver upon a crash. The passenger
`seat covered by each pair. For all measures calculated within
`geously interact with the driver upon a crash. The passenger
`seat covered by each pair. For all measures calculated within
`seat, however, may be occupied by a large or a small
`the algorithm, a contribution is made to an overall fuzzy
`seat, however, may be occupied by a large or a small
`the algorithm, a contribution is made to an overall fuzzy
`occupant including a baby in an infant seat. It can not be
`rating which is used to handle marginal cases.
`occupant including a baby in an infant seat. It can not be 20 rating which is used t0 handle m;irgin3l cases
`assumed that a passenger of any size is at an optimum
`assumed that a passenger of any size is at an optimum
`position (leaning against or near the seat back). An infant
`BRIEF DESCRIPTION OF THE DRAWINGS
`position (leaning against or near the seat back). An infant
`BRIEF DESCRIPTION OF THE DRAWINGS
`seat is normally used in a rear facing position for small
`The above and other advantages of the invention will
`seat is normally used in a rear facing position for small
`babies and in a forward facing position for larger babies and
`The above and other advantages of the invention will
`become more apparent from the following description taken
`babies and in a forward facing position for larger babies and
`small children. While the forward facing position approxi
`25
`in conjunction with the accompanying drawings wherein
`small children. While the forward facing position approxi- 25 become more apparent from the following description taken
`mates the preferred position for airbag interaction, the rear
`like references refer to like parts and wherein:
`mates the preferred position for airbag interaction, the rear
`conjunction with the accompanying drawings wherein
`facing position places the top portion of the infant seat close
`FIG. 1 is a schematic diagram of an SIR system incor
`facing position places the top portion of the infant seat close
`references refer to like parts and wherein:
`to the vehicle dash which houses the airbag. In the latter
`porating a seat occupant detector;
`event. it is desirable to prevent deployment of the airbag.
`FIG. 1 is a schematic diagram of an SIR system incor­
`to the vehicle dash which houses the airbag. In the latter
`FIG. 2 is a position diagram of seat sensors for the system
`porating a seat occupant detector;
`event, it is desirable to prevent deployment of the airbag.
`It has been proposed in US. Pat No. 5,474,327 which
`of FIG. 1, according to the invention;
`will issue Dec. 12, 1995, entitled VEHICLE OCCUPANT
`It has been proposed in U.S. Pat No. 5,474,327 which 30
`FIG. 2 is a position diagram of seat sensors for the system
`RESTRAINT WITH SEAT PRESSURE SENSOR and
`FIG. 3 is a flow chart representing an overview of an
`will issue Dec. 12, 1995, entitled VEHICLE OCCUPANT
`of FIG. 1, according to the invention;
`algorithm for determining deployment permission according
`assigned to the assignee of this invention, to incorporate
`RESTRAINT WITH SEAT PRESSURE SENSOR and
`FIG. 3 is a flow chart representing an overview of an
`pressure sensors in the passenger seat and monitor the
`to the invention;
`assigned to the assignee of this invention, to incorporate
`algorithm for determining deployment permission according
`response of the sensors by a microprocessor to evaluate the
`FIG. 4 is a flow chart representing a method of computing
`pressure sensors in the passenger seat and monitor the
`to the invention;
`weight distribution and determine the type of occupant and
`decision measures used in the algorithm of FIG. 3;
`response of the sensors by a microprocessor to evaluate the
`FIG. 4 is a flow chart representing a method of computing
`the facing direction of an infant seat. The sensor arrange
`FIG. 5 is a graphical representation of a function used in
`weight distribution and determine the type of occupant and
`ment and the algorithm successfully cover most cases of seat
`decision measures used in the algorithm of FIG. 3;
`fuzzy logic for total force and load ratings;
`the facing direction of an infant seat. The sensor arrange­
`occupancy. It is desirable, however, to encompass every case
`FIG. 5 is a graphical representation of a function used in
`FIG. 6 is a graphical representation of a function used in
`ment and the algorithm successfully cover most cases of seat
`of seat occupancy.
`fuzzy logic for total force and load ratings;
`fuzzy logic for determining load rating;
`occupancy. It is desirable, however, to encompass every case
`FIG. 6 is a graphical representation of a function used in
`FIG. 7 is a position diagram of seat sensors illustrating
`SUMMARY OF THE INVENTION
`of seat occupancy.
`fuzzy logic for determining load rating;
`sensor grouping;
`It is therefore an object of the invention to detect a
`SUMMARY OF THE INVENTION
`FIG. 8 is a ?ow chart for deployment decision, according
`FIG. 7 is a position diagram of seat sensors illustrating
`comprehensive range of vehicle seat occupants including
`to the invention; and
`sensor grouping;
`infant seats for a determination of whether an airbag deploy
`It is therefore an object of the invention to detect a
`FIG. 9 is a ?ow chart representing the logic for deter
`ment should be permitted. Another object in such a system
`FIG. 8 is a flow chart for deployment decision, according
`comprehensive range of vehicle seat occupants including
`mining the facing direction of an infant seat as required by
`is to determine whether an infant seat is facing the front or
`45 to the invention; and
`infant seats for a determination of whether an airbag deploy­
`the algorithm of FIG. 8.
`the rear. Another object is to include sensitivity to the
`FIG. 9 is a flow chart representing the logic for deter­
`ment should be permitted. Another object in such a system
`possible seating positions of small children.
`mining the facing direction of an infant seat as required by
`is to determine whether an infant seat is facing the front or
`DESCRIPTION OF THE INVENTION
`A SIR system, as is well known, has an acceleration
`the algorithm of FIG. 8.
`the rear. Another object is to include sensitivity to the
`Referring to FIG. 1, a SIR system includes a SIR module
`sensor to detect an impending crash, a microprocessor to
`possible seating positions of small children.
`13 coupled to a seat occupant sensing system 14. The SIR
`process the sensor signal and to decide whether to deploy an
`DESCRIPTTON OF THE INVENTION
`A SIR system, as is well known, has an acceleration
`airbag, and a deployment unit ?red by the microprocessor.
`module 13 includes an accelerometer 15 mounted on the
`Referring to FIG. 1, a SIR system includes a SIR module
`sensor to detect an impending crash, a microprocessor to
`vehicle body for sensing an impending crash, a micropro
`An occupant detection system can determine if an occupant
`cessor 16 for receiving a signal from the accelerometer and
`13 coupled to a seat occupant sensing system 14. The SIR
`process the sensor signal and to decide whether to deploy an
`or infant seat is positioned in a way to not bene?t from
`for deciding whether to deploy an airbag. An airbag deploy
`deployment, and then signaling the microprocessor whether
`module 13 includes an accelerometer 15 mounted on the
`airbag, and a deployment unit fired by the microprocessor.
`ment unit 18 is controlled by the microprocessor 16 and ?res
`to allow or inhibit deploying the airbag.
`An occupant detection system can determine if an occupant 55 vehicle body for sensing an impending crash, a micropro-
`a pyrotechnic or compressed gas device to in?ate an airbag
`A dozen sensors, judicially located in the seat, can garner
`or infant seat is positioned in a way to not benefit from
`cessor 16 for receiving a signal from the accelerometer and
`when a deploy command is received. A fault indicator 20,
`su?icient pressure and distribution information to allow
`deployment, and then signaling the microprocessor whether
`for deciding whether to deploy an airbag. An airbag deploy­
`also controlled by the microprocessor 16 will show a failure
`determination of the occupant type and infant seat position.
`to allow or inhibit deploying the airbag.
`ment unit 18 is controlled by the microprocessor 16 and fires
`of the seat occupant sensing system 14.
`This information, in turn, can be used as desired to inhibit
`a pyrotechnic or compressed gas device to inflate an airbag
`A dozen sensors, judicially located in the seat, can garner
`The seat occupant sensing system 14 comprises a micro
`SIR deployment. The sensors are arranged symmetrically
`sufficient pressure and distribution information to allow 50 when a deploy command is received. A fault indicator 20,
`processor 22 having a 5 volt supply and an enabling line 24
`about the seat centerline and includes a front pair, a right
`also controlled by the microprocessor 16 will show a failure
`determination of the occupant type and infant seat position.
`periodically provided with a 5 volt enabling pulse, and a
`pair, a rear pair, a left pair and four in the center. Each sensor
`65
`of the seat occupant sensing system 14.
`This information, in turn, can be used as desired to inhibit
`series of voltage dividers coupled between the enabling ~line
`is a very thin resistive device, having lower resistance as
`SIR deployment. The sensors are arranged symmetrically
`The seat occupant sensing system 14 comprises a micro­
`2A and ground. Each voltage divider has a ?xed resistor 26
`pressure increases. A microprocessor is programmed to
`about the seat centerline and includes a front pair, a right
`processor 22 having a 5 volt supply and an enabling line 24
`pair, a rear pair, a left pair and four in the center. Each sensor 65 periodically provided with a 5 volt enabling pulse, and a
`is a very thin resistive device, having lower resistance as
`series of voltage dividers coupled between the enabling line
`pressure increases. A microprocessor is programmed to
`24 and ground. Each voltage divider has a fixed resistor 26
`
`50
`
`35
`
`40
`
`55
`
`Aisin Seiki Exhibit 1008
` Page 6
`
`

`
`5,732,375
`5 ,732,375
`4
`3
`4
`3
`in series with a pressure sensor or variable resistor 28, and
`The next step in FIG. 4 is to determine the load rating of
`The next step in FIG. 4 is to determine the load rating of
`the junction point of each resistor 26 and variable resistor 28
`each sensor <52>. The load rating is a measure of whether
`in series with a pressure sensor or variable resistor 28, and
`each sensor <52>. The load rating is a measure of whether
`the junction point of each resistor 26 and variable resistor 28
`the sensor is detecting some load and is used for pattern
`is connected to an A/D port 30 of the microprocessor 22. The
`the, sensor is detecting some load and is used for pattern
`is connected to an A/D port 30 of the microprocessor 22. The
`recognition purposes. Low loads present a borderline case
`microprocessor 22 controls the pulse on enabling line 24 and
`recognition purposes. Low loads present a borderline case
`microprocessor 22 controls the pulse on enabling line 24 and
`reads each sensor 28 voltage during the pulse period. The 5 which is rated by fuzzy logic according to a function similar
`which is rated by fuzzy logic according to a function similar
`reads each sensor 28 voltage during the pulse period. The
`to that of FIG. 5. As shown in FIG. 6, if a load is below a
`microprocessor 22 analyzes the sensor inputs and issues a
`to that of FIG. 5. As shown in FIG. 6, if a load is below a
`microprocessor 22 analyzes the sensor inputs and issues a
`base value d, which may be four, the rating is zero and if it
`decision whether to inhibit airbag deployment and the
`base value d, which may be four. the rating is zero and if it
`decision whether to inhibit airbag deployment and the
`is above the base value it is the difference between the base
`decision is coupled to the microprocessor 16 by a line 32.
`is above the base value it is the dilference between the base
`decision is coupled to the microprocessor 16 by a line 32.
`and the measured load up to a limit value of, say, four. The
`The microprocessor 22 also monitors its decisions for con­
`and the measured load up to a limit value of, say, four. The
`The microprocessor 22 also monitors its decisions for con
`sistency and issues a fault signal on line 34 to the micro-
`total load rating is calculated <54> by summing the indi-
`total load rating is calculated <54> by summing the indi
`sistency and issues a fault signal on line 34 to the micro
`processor 16 if faults continue to occur over a long period.
`vidual sensor ratings and the fuzzy contribution of the total
`vidual sensor ratings and the fuzzy contribution of the total
`processor 16 if faults continue to occur over a long period.
`Each fixed resistor 26 is, for example, 10 kohms and the
`load rating is again determined as in FIG. 5 where a total
`Each ?xed resistor 26 is. for example. 10 kohms and the
`load rating is again determined as in FIG. 5 Where a total
`variable resistors vary between 10 kohms at high pressure
`load below a minimum threshold b is zero, a total load above
`variable resistors vary between 10 kohms at high pressure
`load below a minimum threshold b is zero, a total load above
`and 100 kohms at low pres sure. Then the voltage applied to
`and 100 kohms at low pressure. Then the voltage applied to
`the minimum is the total load minus the minimum threshold
`the minimum is the total load minus the minimum threshold
`the ports 30 will vary with pressure. Each sensor comprises
`the ports 30 will vary with pressure. Each sensor comprises
`up to a limit at maximum threshold 0. The minimum
`up to a limit at maximum threshold c. The minimum
`two polyester sheets each having a ?lm of resistive ink
`two polyester sheets each having a film of resistive ink 15
`threshold may be four, for example, and the maximum
`threshold may be four, for example, and the maximum
`connected to a conductive electrode, the two resistive ?lms
`connected to a conductive electrode, the two resistive films
`threshold may be 24.
`threshold may be 24.
`contacting one another such that the resistance between
`contacting one another such that the resistance between
`Next a check is made for force concentration in a local
`Next a check is made for force concentration in a local­
`electrodes decreases as pressure increases. Such pressure
`electrodes decreases as pressure increases. Such pressure
`ized area <56>. Four overlapping localized areas are de?ned
`ized area <56>. Four overlapping localized areas are defined
`sensors are available as ALPS pressure sensors from Alps
`sensors are available as ALPS pressure sensors from Alps
`as shown in FIG. 7. The front four sensors 1, 6, 7 and 12 are
`Electric Co. Ltd, Tokyo. Japan.
`20
`20 as shown in FIG. 7. The front four sensors 1,6,7 and 12 are
`Electric Co, Ltd, Tokyo, Japan.
`in the front group, the rear eight sensors 2, 3, 4, S, 8, 9. 10
`The mounting arrangement of sensors 28 on a bottom
`in the front group, the rear eight sensors 2, 3, 4, 5, 8, 9, 10
`and 11 are in the rear group, the left eight sensors 1, 2, 3. 4,
`The mounting arrangement of sensors 28 on a bottom
`bucket seat cushion is shown in FIG. 2. The sensors are
`and 11 are in the rear group, the left eight sensors 1, 2, 3,4,
`5. 6. 8, and 9 are in the left group, and the eight sensors 4,
`bucket seat cushion is shown in FIG. 2. The sensors are
`numbered 1-12 according to seat location. A left pair of
`5, 6, 8, and 9 are in the left group, and the eight sensors 4,
`5, 7, 8. 9. 10, 11, and 12 are in the right group. The algorithm
`numbered 1-12 according to seat location. A left pair of
`sensors 1 and 2 are on the left side of the seat with sensor
`5,7,8,9,10,11, and 12 are in the right group. The algorithm
`determines if the pressure is all concentrated in one group by
`sensors 1 and 2 are on the left side of the seat with sensor
`2 to the rear and slightly inboard of sensor 1. Sensors 11 and
`25
`determines if the pressure is all concentrated in one group by
`summing the load ratings of the sensors in each group and
`2 to the rear and slightly inboard of sensor 1. Sensors 11 and 25
`12 are the corresponding right pair of sensors. A front pair
`comparing to the total load rating. If the rating sum of any
`summing the load ratings of the sensors in each group and
`12 are the corresponding right pair of sensors. A front pair
`of sensors 6 and 7 are at the front of the seat and a rear pair
`group is equal to the total rating, a ?ag is set for that group
`comparing to the total load rating. If the rating sum of any
`of sensors 3 and 10 are at the rear. The four remaining
`of sensors 6 and 7 are at the front of the seat and a rear pair
`(all right, all front etc.).
`group is equal to the total rating, a flag is set for that group
`sensors 4. 5. 8 and 9 are the center group of sensors. Sensors
`of sensors 3 and 10 are at the rear. The four remaining
`Finally the force and fuzzy contribution is computed for
`5 and 8 are astride the seat centerline and are just in front of
`(all right, all front etc.).
`sensors 4, 5, 8 and 9 are the center group of sensors. Sensors
`each pair of sensors and for the center group <58>. The force
`sensors 4 and 9. The center group is positioned just to the
`5 and 8 are astride the seat centerline and are just in front of 30
`Finally the force and fuzzy contribution is computed for
`on each pair is used to detect occupants such as small
`rear of the seat middle.
`sensors 4 and 9. The center group is positioned just to the
`each pair of sensors and for the center group <58>. The force
`children which can easily sit in one small area of the seat.
`The method of operation is illustrated by a series of
`rear of the seat middle.
`on each pair is used to detect occupants such as small
`These measures are looking for the pressure to be evenly
`?owcharts wherein the functional description of each block
`children which can easily sit in one small area of the seat.
`The method of operation is illustrated by a series of
`distributed over the two sensors of the pair. To accomplish
`in the chart is accompanied by a number in angle brackets
`35
`These measures are looking for the pressure to be evenly
`flowcharts wherein the functional description of each block
`this the algorithm looks at each pair, determines the mini
`<nn> which corresponds to the reference number of the
`in the chart is accompanied by a number in angle brackets 35 distributed over the two sensors of the pair. To accomplish
`mum value of the two sensors, and clip the higher one to a
`block. The overall operation is shown in FIG. 3 wherein the
`this the algorithm looks at each pair, determines the mini­
`<nn> which corresponds to the reference number of the
`calibrated “delta” from the lower. If the force is evenly
`sensor values are read by the microprocessor 22 <36> and
`mum value of the two sensors, and clip the higher one to a
`block. The overall operation is shown in FIG. 3 wherein the
`distributed over the two sensors the values will be about
`the data is adjusted by bias correction and low pass ?ltering
`calibrated "delta" from the lower. If the force is evenly
`equal and the sum will be una?ected by clipping. The sum
`sensor values are read by the microprocessor 22 <36> and
`68>. One sensor at a time is turned on, sampled four times
`distributed over the two sensors the values will be about
`of the two sensor forces, as adjusted, comprise the force
`the data is adjusted by bias correction and low pass filtering
`and averaged. Then a bias calibrated for each sensor is
`measure of the pair. The fuzzy contribution of each pair is
`<38>. One sensor at a time is turned on, sampled four times 40 equal and the sum will be unaffected by clipping. The sum
`subtracted from each sensor reading, and the data is ?ltered
`equal to the force measure of the pair but limited to a
`of the two sensor forces, as adjusted, comprise the force
`with a time constant on the order of 1 second. Then all
`and averaged. Then a bias calibrated for each sensor is
`maximum value such as 20 which is calibrated separately for
`decision measures are computed <40> and decision algo
`measure of the pair. The fuzzy contribution of each pair is
`subtracted from each sensor reading, and the data is filtered
`each pair.