US006959970B2
`
`(12)
`
`United States Patent
`Tseng
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 6,959,970 B2
`Nov. 1, 2005
`
`(54) METHOD AND APPARATUS FOR
`CONTROLLING A TRAILER AND AN
`AUTOMOTIVE VEHICLE WITH A YAW
`STABILITY CONTROL SYSTEM
`
`_
`.
`(75) Inventor. Eric E. Tseng, Canton, MI (US)
`_
`_
`(73) Ass1gnee: Ford Global Technologies, LLC,
`Dearborn, MI (Us)
`
`(*) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(k)) by 0 days.
`
`(21) APPL NO; 10/703,632
`
`(22) Filed:
`
`Mar- 18’ 2004
`
`7/1992 Matsumoto et al.
`5,134,352 A
`5,172,961 A 12/1992 Inoue et a1.
`5,696,681 A 12/1997 HIOVM et 91
`5,747,683 A *
`5/1998 Gerum et al. ............... .. 701/72
`6,021,367 A
`2/2000 Pilutti et al.
`6,042,196 A *
`3/2000 Nakamura et al. .... .. 188/112 R
`6,059,383 A
`50000 Paggi et a1‘
`6,076,033 A
`6/2000 Hamada et al.
`6,132,014 A 100000 Kl-SO et a1‘
`6,176,555 B1 *
`1/2001 Semsey .................... .. 303/146
`
`4/2001 Boros et al. . . . . . .
`. . . .. 701/72
`6,223,114 B1 *
`5/2001 Tachihata et a1. ........... .. 701/72
`6,226,587 B1 *
`1/2002 Kawagoe et al.
`6,338,015 B1
`4/2002 Tanaka et al. ............ .. 303/147
`6,374,162 B1 *
`6,494,281 B1 * 12/2002 Faye et al. ................ .. 180/197
`6,588,858 B2
`7/2003 Ritz et 81.
`6,612,394 B2
`9/2003 Wessman
`FOREIGN PATENT DOCUMENTS
`
`(65)
`
`Prior Publication Data
`
`GB
`
`2 188 012 A
`
`9/1987
`
`US 2005/0206235 A1
`
`Sep. 22, 2005
`
`* cited by examiner
`
`(51) Int. c1.7 ............................ .. B60T 8/60; B60T 8/24
`(52) US. Cl. ........................ .. 303/146; 303/123; 303/7;
`188/112 R~ 701/72
`’
`(58) Field of Search .......................... .. 303/7, 123, 140,
`303/146’ 147’ 148; 701/71’ 72’ 74’ 75; 188/112 A’
`188/112 R
`
`(56)
`
`References Cited
`
`US. PATENT DOCUMENTS
`
`3,993,362 A * 11/1976 Kamins et al. ........... .. 303/146
`4,700,966 A * 10/1987 Hawkins et a1.
`280/432
`5,029,948 A *
`7/1991 Breen et al.
`.. 188/112A
`5,033,798 A *
`7/1991 Breen ................... .. 188/112A
`
`Primary Examiner—Thomas Williams
`(74) Attorney) Agent) 0’ Fi””—Greg Brown
`
`ABSTRACT
`
`57
`(
`)
`A system and method of controlling an automotive vehicle
`With a yaW stability control system and a trailer comprises
`determining a presence of a trailer, changing a side slip angle
`parameter threshold of the vehicle to a modi?ed side slip
`parameter in response to the trailer signal, and controlling
`the yaW stability control system in response to the modi?ed
`side slip parameter.
`
`14 Claims, 11 Drawing Sheets
`
`'
`
`lZa.
`
`Throttle Engine
`
`Peda'
`
`Trans
`mission
`
`Engine
`Controller
`
`\
`.
`
`1
`
`I
`
`I
`
`' 724 '
`
`II:
`
`I56
`
`I54
`
`3 Transfer Case
`
`Controtlsr
`
`I36
`
`132a.
`
`13a.
`
`Rear Di?erenlial _ _ _ _
`
`Trailer Brake Controller
`
`‘I
`
`.‘ 1'
`
`\
`
`,
`
`HI
`Hams“ Sensor
`
`/ 7%
`
`m ,
`
`Petitioners Ex. 1004 Page 1
`
`

`

`US. Patent
`U.S. Patent
`
`Nov. 1,2005
`Nov. 1, 2005
`
`Sheet 1 0f 11
`Sheet 1 0f 11
`
`US 6,959,970 B2
`US 6,959,970 132
`
`
`
`10
`
`24
`
`1%
`
`do
`
`U.
`
`FIG.2
`
`Petitioners Ex. 1004 Page 2
`
`Petitioners Ex. 1004 Page 2
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 2 0f 11
`
`US 6,959,970 B2
`
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`Petitioners Ex. 1004 Page 3
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 3 0f 11
`
`US 6,959,970 B2
`
`ad’
`
`12%
`
`w
`
`162a.
`
`Traiier
`
`1660:.
`
`l PISA
`
`Petitioners Ex. 1004 Page 4
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 4 0f 11
`
`US 6,959,970 B2
`
`[L f [79
`
`2'
`77
`L53 :76
`
`\“H Display
`
`10
`
`E
`
`66’
`
`FIG.5
`
`FIG.5A
`
`w I:
`
`Petitioners Ex. 1004 Page 5
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 5 0f 11
`
`US 6,959,970 B2
`
`FIG]
`
`Suspension
`
`Control Z
`194
`
`FIG.8
`
`Petitioners Ex. 1004 Page 6
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`

`

`U.S. Patent
`
`Nov. 1, 2005
`
`Sheet 6 0f 11
`
`US 6,959,970 B2
`
`Monitor Sensors
`
`f 30 7
`
`Betermine Steering / Z05’
`Wheei Angie
`i
`Determine
`Wheei Direction
`i
`Determine Steering / 2/0
`Wheei Rate
`
`L/ 20 9
`
`v
`
`/ 27/
`
`,2/4
`
`Determine a Steering
`Wneei Yorque
`1
`Monitor Vehicte Systems f 272
`i
`Determine if VehicEe
`in Parking Mode
`t
`Determine Vehieie Loading
`/
`
`Apply Brake Steer
`
`1?
`
`/
`Modify Suspension
`
`2120
`
`t
`Apply Brakes
`
`t
`Apply Po
`sitive
`Torque or Differential
`
`r4
`r,
`Pressure Feedback
`Throogh Steering
`Hand Wheet
`I
`F|G.1O
`
`Petitioners Ex. 1004 Page 7
`
`

`

`US. Patent
`
`Nov. 1, 2005
`
`Sheet 7 0f 11
`
`US 6,959,970 B2
`
`100%
`
`T1
`
`T1!
`
`FIG . 1 1
`
`Brake Steer
`Entry Threshoid
`
`Lock
`
`100%
`
`Brake-Steer SWA
`Brake-Steer
`
`V < 10mph
`
`0
`
`T3;
`
`T3
`Brake Steer
`
`Torque Threshotd
`
`P4
`
`P5
`
`T4(MAX)
`
`FIG.12
`
`Petitioners Ex. 1004 Page 8
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`Petitioners Ex. 1004 Page 8
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`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 8 0f 11
`
`US 6,959,970 B2
`
`Max
`
`Brake
`Steer
`
`it
`
`Max *
`
`Bmke
`Steer
`
`V = 0 ~ 2 mph
`
`TMAX
`
`T5
`
`SWA
`
`V r 0 - 2 mph
`
`SWA
`
`Determine Vehicie Direction
`
`Z32
`5
`Apply Brake Steer When
`Conditions Above First Threshotd
`
`234
`;
`u
`Appiy Brake Steer when
`Conditions Above Second
`Threshold that is Different
`than First Threshold
`
`2‘ 3 6
`5
`
`i
`Apply
`Brakes
`
`l
`
`l
`
`i
`Appty Positive!
`Differentiat Torque
`
`240
`5
`
`i
`Modify
`Suspension
`
`Petitioners Ex. 1004 Page 9
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 9 0f 11
`
`US 6,959,970 B2
`
`Case 1
`Vehicie going Forward
`
`[2a
`
`‘1
`
`; 10
`
`204a.
`
`Direction
`of Travel “
`
`20?
`
`km 200 f
`l2b
`13b
`
`L!
`
`2041:
`
`Caso 2 _
`vehicie going backwards
`
`lZa 75E]
`
`Direction
`of Travel
`
`/.2b
`
`l
`
`|
`
`[/0
`5
`
`n
`
`13a
`/
`
`5;] 2%:
`202%
`200*’
`Eli/Z, 2041
`m» J
`F|G.17
`
`U
`
`Case 3
`Vehicie going forwards, split p
`
`13.9;
`
`'r
`
`Petitioners Ex. 1004 Page 10
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`

`

`U.S. Patent
`
`Nov. 1, 2005
`
`Sheet 10 0f 11
`
`US 6,959,970 B2
`
`5
`
`_/ 250
`
`Determine if Vehicle
`is Trailering
`l
`Meniforf Adjust / 252
`Vehicle Systems
`
`L
`Monitor Vehicle Sensors
`
`J 25¢
`
`5 266
`‘r
`Straight High Speed
`}
`5- 2 6 <5’
`{Determine Condiilons
`
`Y Z 70
`1i’
`Determme Pro?le
`
`2.56
`;
`
`§ 26 4
`Turning Forward
`L
`Yaw Rate from Hand
`Wheel Compared to
`5' 260
`1
`ActealYew Rate
`\265 Display Prmected Path
`
`Reverse
`f‘ .256’
`l
`Provide Turning input
`
`' Generate Brake Steer =
`2 71¢
`.7’ F‘“—
`“\- 262
`Activate Vehicle Brakes
`..—|
`
`as,
`‘276
`
`Apply Pesitivel
`Differential Torque
`
`‘
`'
`Med‘fy S
`r
`uspensron
`
`280
`
`Activate Trailer
`Brakes
`
`5* Z 76’
`FIG.19
`
`Petitioners Ex. 1004 Page 11
`
`

`

`U.S. Patent
`
`Nov. 1,2005
`
`Sheet 11 0f 11
`
`US 6,959,970 B2
`
`Detect U-turn
`
`-/ 300
`
`L
`Activate Brake Steer
`
`30
`"f
`‘2
`
`Activate Vehicle
`Brakes
`/
`304
`
`Appiy Positive!
`Activate Trailer
`Differential Torque
`Brakes
`(Joe
`/
`FIG.21
`.306
`
`Modify
`pension
`Sus
`{370
`
`1
`
`[3467
`
`‘r342
`
`Menitor Vehicle Sensors
`l
`Monitor Object
`Detection System
`l
`Determine Distance to Object
`l
`Determine Likelihood
`of Impact
`i
`
`No Impact
`
`I
`
`Impact Likely
`l
`Apply Brakes in
`Proportion to the
`Distance of the Object
`l
`Continue to
`Monitor Distance
`
`350
`
`,952
`
`/354
`
`FlG.22
`
`Brake Steer
`
`Petitioners Ex. 1004 Page 12
`
`

`

`US 6,959,970 B2
`
`1
`METHOD AND APPARATUS FOR
`CONTROLLING A TRAILER AND AN
`AUTOMOTIVE VEHICLE WITH A YAW
`STABILITY CONTROL SYSTEM
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`2
`a trailer comprises determining a presence of a trailer,
`changing a side slip angle parameter threshold of the vehicle
`to a modi?ed side slip parameter in response to the trailer
`signal, and controlling the yaW stability control system in
`response to the modi?ed side slip parameter.
`
`BRIEF DESCRIPTION OF DRAWINGS
`
`The present invention is related to US. application Ser.
`Nos. 10/708,668, 10/708,669, 10/708,670, 10/708,671,
`10/708,672, 10/708,673, 10/708,675, 10/708,676, 10/708,
`677, 10/708,679, 10/708,680, and 10/708,681, all ?led Mar.
`18, 2004, each incorporated by reference herein.
`
`BACKGROUND OF INVENTION
`
`The present invention relates generally to a dynamic
`control system for an automotive vehicle, and more particu
`larly, to a system of enhancing the trailerability of a vehicle
`using a yaW stability control system.
`Dynamic control systems for automotive vehicles have
`recently begun to be offered on various products. Dynamic
`control systems typically control the yaW of the vehicle by
`controlling the braking effort at the various Wheels of the
`vehicle. YaW control systems typically compare the desired
`direction of the vehicle based upon the steering Wheel angle
`and the direction of travel. By regulating the amount of
`braking at each corner of the vehicle, the desired direction
`of travel may be maintained.
`Such systems typically include the capability of control
`ling one Wheel or multiple Wheels individually. That is, the
`vehicle Wheels may be braked individually. Individual brak
`ing is typically performed on a demand basis for a relatively
`short time to stabiliZe the vehicle. Further, a vehicle Wheel
`may be provided With a different torque than the other
`Wheels. This may be desirable to perform certain controls in
`dynamic stability control systems.
`Large vehicles such as fullsiZe sport utility vehicles,
`pickup trucks, and heavy duty trucks have a large turning
`radius. Such vehicles may be used to pull trailers. It Would
`be desirable to improve the turning characteristics of these
`vehicles by reducing the turning radius. It Would also be
`desirable to improve the trailering characteristics of a
`vehicle.
`One system that is knoWn to improve the turning char
`acteristics of the vehicle is a four Wheel steer system. By
`steering the rear Wheels in the opposite direction of the front
`Wheels in loW speed, the turning radius of the vehicle is
`reduced. Four Wheel steering is also capable of improving
`the trailerability of a vehicle in high speed. One draWback to
`such a system is that the system adds another steering
`actuator to the vehicle. This increases the cost, complexity,
`Warranty, maintenance costs and Weight of the vehicle. In
`contrast, it is typically the objective today to reduce the cost
`and Weight of vehicles.
`It Would therefore be desirable to improve the turning
`capability and trailerability of vehicles Without incurring the
`draWbacks of a four Wheel steering system.
`
`SUMMARY OF INVENTION
`
`The present invention provides a system that adjusts the
`parameters of the yaW stability control system When traile
`ring to enhance the maneuverability of the vehicle and
`trailer.
`In one aspect of the invention, a method of controlling an
`automotive vehicle With a yaW stability control system and
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`FIG. 1 is plot of a vehicle traveling along three curves
`corresponding to a conventional vehicle and tWo embodi
`ments of the invention.
`FIG. 2 is a perspective vieW of an automotive vehicle on
`a road surface having a control system according to the
`present invention.
`FIG. 3 is a block diagrammatic vieW of a control system
`according to the present invention.
`FIG. 4 is a high level block diagrammatic vieW of systems
`of the automotive vehicle according to the present invention.
`FIG. 5 is a perspective vieW of a trailer locating plate
`coupled to a trailer tongue relative to the vehicle.
`FIG. 5A is a perspective vieW of the toe locating plate of
`FIG. 5.
`FIG. 5B is a top vieW of an apparatus for determining the
`position of the trailer.
`FIG. 6 is a perspective vieW of a Hotchkiss suspension
`having an active compliant suspension component accord
`ing to the present invention.
`FIG. 7 is a perspective vieW of an independent suspen
`sion.
`FIG. 8 is an exploded vieW of a toW link of an independent
`suspension.
`FIG. 9 is a simpli?ed vieW of an electric vehicle that may
`use brake-steer according to the present invention.
`FIG. 10 is a How chart of a ?rst embodiment of the present
`invention.
`FIG. 11 is a plot of various boost curves relative to an
`amount of brake steering Wheel angle dependent upon
`steering Wheel rate or torque.
`FIG. 12 is a plot of various boost curves relative to an
`amount of torque.
`FIG. 13 is a plot of a boost curve used from a vehicle V:
`0 to a loW velocity threshold.
`FIG. 14 is a second embodiment plot of a boost curve used
`from V=0 to a loW velocity threshold.
`FIG. 15 is a How chart illustrating a method of operating
`a second embodiment of the present invention.
`FIG. 16 is a simpli?ed top vieW of a vehicle having a
`controllable suspension illustrating brake-steer in a forWard
`direction.
`FIG. 17 is a simpli?ed top vieW of a vehicle having a
`controllable suspension illustrating brake-steer in a reverse
`direction.
`FIG. 18 is a simpli?ed top vieW of a vehicle having a
`controllable suspension illustrating brake-steer on a split mu
`surface.
`FIG. 19 is a block diagrammatic vieW of a third embodi
`ment of the present invention.
`FIG. 20 is a plot of a screen display of a trailer and vehicle
`With predicted positions.
`FIG. 21 is a How chart of a fourth embodiment of the
`present invention.
`FIG. 22 is a How chart of a ?fth embodiment of the
`present invention.
`
`Petitioners Ex. 1004 Page 13
`
`

`

`US 6,959,970 B2
`
`3
`DETAILED DESCRIPTION
`
`In the following ?gures the same reference numerals Will
`be used to identify the same components. The various terms
`and values are set forth by Way of example and are not meant
`to be limiting unless speci?cally set forth in a claim.
`Referring noW to FIG. 1, a vehicle 10 is illustrated
`traversing three paths. Path A1 is the path a vehicle travels
`Without the invention. Path A2 is a path the vehicle 10
`travels With brake-steer. Path A3 is a path the vehicle 10
`travels With brake-steer and a controllable suspension com
`ponent. As is shoWn, path A2 improves the turning radius
`over path A1. Path A3 has a reduced or improved turning
`radius compared to path A2.
`The term brake-steer or brake-steering is used to describe
`changing a characteristic of the vehicle such as the turning
`radius or tracking of the vehicle using one or more brakes,
`the application of differential (positive or negative) torques,
`or a combination of the braking and differential torques.
`Positive torques may be applied by use of electric drive
`motors (With or Without an electric vehicle), active differ
`entials, or traditional torque distribution methods. Active
`differentials are capable of diverting all or part of the drive
`torque to one side of the vehicle or the other. Also, speci?c
`con?gurations may depend on different vehicle arrange
`ments including poWertrain, Weight, loading, tires and the
`other desired effects. Vehicles employing such systems Will
`be calibrated and/or adjusted experimentally. The present
`invention is particularly suitable for use in long Wheel base
`vehicles. HoWever, shorter Wheel base vehicles may also
`bene?t from implementation of this invention.
`The present invention may be used With various dynamic
`control systems such as, but not limited to, antilock brakes,
`traction control, roll stability control and yaW control sys
`tems. The present invention is discussed beloW in terms of
`preferred embodiments relating to an automotive vehicle
`moving in a three-dimensional road terrain, but it is to be
`understood that such descriptors are not to be limiting on the
`full range and scope of the present invention. Further, the
`various sensors may be used alone or in various combina
`tions depending on the conditions. Other sensors may be
`used to complement or verify determinations of other sen
`sors. For example, some sensors may be used to check the
`image or radar signals, or vice versa.
`Referring to FIG. 2, an automotive vehicle 10 With a
`control system of the present invention is illustrated. Vehicle
`10 has front right and front left tires 12a and 12b and rear
`right tires 13a and rear left tires 13a and 13b, respectively.
`The vehicle 10 may also have a number of different types of
`front steering systems 14a including having each of the front
`Wheels con?gured With a respective controllable actuators
`and the front Wheels having a conventional type system in
`Which both of the front Wheels are controlled together. The
`vehicle has a rear axle system 14b. Generally, the vehicle has
`a Weight represented as Mg at the center of gravity of the
`vehicle, Where g=9.8 m/s2 and M is the total mass of the
`vehicle.
`The sensing system 16 may share sensors With other
`vehicle dynamic control systems such as a yaW stability
`control system sensor set or a roll stability control system
`sensor set. Of course, the actual sensors used Will vary
`depending on the type of control system or systems imple
`mented on the particular vehicle. The various possible
`sensors Will be further described beloW. The Wheel speed
`sensors 20 may be mounted as adjacent each Wheel of the
`vehicle. Those skilled in the art Will recogniZe three Wheel
`speed sensors may be used. For example, one for the rear of
`
`10
`
`15
`
`25
`
`35
`
`40
`
`45
`
`55
`
`65
`
`4
`the vehicle and one for each of the front tWo Wheels. The
`remaining sensors of sensing system 16 are preferably
`mounted directly at the center of gravity of the vehicle,
`along the reference directions x, y and Z shoWn in FIG. 1. As
`those skilled in the art Will recogniZe, the frame from b1, b2
`and b3 is called a body reference frame 22, Whose origin is
`located at the center of gravity of the car body, With the b1
`corresponding to the x axis pointing forWard, b2 correspond
`ing to the y axis pointing off the left side, and the b3
`corresponding to the Z axis pointing upWard. The angular
`rates of the car body are denoted about their respective axes
`as 00x for the roll rate, my for the pitch rate, and (n2 for the yaW
`rate. The present invention calculations preferably take
`place in an inertial frame 24 that may be derived from the
`body reference frame 22 as described beloW.
`As Will be described beloW, the sensing system 16 may
`also include a lidar, radar and/or sonar sensor(s), camera(s),
`a GPS system and various other sensors (all of Which are
`shoWn in FIG. 2 or 3 beloW).
`The angular rate sensors and the accelerometers are
`mounted on the vehicle along the body frame directions b1,
`b2 and b3, Which are the x axes of the vehicle’s sprung mass.
`The longitudinal acceleration sensor is mounted on the
`vehicle located at the center of gravity, With its sensing
`direction along the bl-axis, Whose output is denoted as a.
`The lateral acceleration sensor is mounted on the car body
`located at the center of gravity, With its sensing direction
`along b2-axis, Whose output is denoted as ay. The vertical
`acceleration sensor is mounted on the car body located at the
`center of gravity, With its sensing direction along b3-axis,
`Whose output is denoted as aZ.
`The other reference frames used in the folloWing discus
`sion includes the road reference frame, as depicted in FIG.
`2. The road reference frame system rlrzr3 is ?xed on the
`driven road surface at any instant in travel time of the
`vehicle, Where the r3 axis is along the average road normal
`direction computed from the normal directions of the four
`tire/road contact patches.
`In the folloWing discussion, the Euler angles of the body
`frame b1b2b3 With respect to the road frame r1r2r3 are
`denoted as em, Gyb, and 6217,, Which are also called the
`relative Euler angles.
`Referring noW to FIG. 3, control system 18 is illustrated
`in further detail having a controller 26. Controller 26 in this
`case may be a single centraliZed vehicle controller or a
`combination of controllers. If many controllers are used they
`may be coupled together to communicate various informa
`tion therebetWeen, and arbitration and prioritiZation among
`multiple controllers might also be performed. Preferably, the
`controller 26 is microprocessor-based.
`The controller 26 may be programmed to perform various
`functions and control various outputs. Controller 26 may
`also have a memory 27 associated thereWith. Memory 27
`may be a stand-alone memory or may be incorporated Within
`the controller 26. Memory 27 may store various parameters,
`thresholds, patterns, tables or maps. For example, a map of
`hoW much brake-steer to generate in response to steering
`Wheel rate and vehicle velocity may be stored in memory.
`Such maps may be calibratable during vehicle development.
`The controller 26 is used for receiving information from
`a number of sensors, Which may include speed sensors 20,
`a yaW rate sensor 28, a lateral acceleration sensor 32, a roll
`rate sensor 34, a vertical acceleration sensor 35, a longitu
`dinal acceleration sensor 36, a pitch rate sensor 37, and
`steering angle position sensor 38. Sensors 28—38 may be part
`of an inertial measurement unit 40 or IMU.
`
`Petitioners Ex. 1004 Page 14
`
`

`

`US 6,959,970 B2
`
`5
`In one embodiment, the sensors 28—37 are located at the
`center of gravity of the vehicle. Those skilled in the art Will
`recognize that the sensors may also be located on various
`locations off the center of gravity and mathematically trans
`lated equivalently thereto.
`Roll rate sensor 34 and pitch rate sensor 37 may be used
`to sense the vehicle roll and pitch conditions. The roll and
`pitch conditions of the vehicle might be conducted based on
`sensing the height of one or more points on the vehicle
`relative to the road surface. Sensors that may be used to
`achieve this include a radar-based proximity sensor, a laser
`based proximity sensor and a sonar-based proximity sensor.
`Roll and pitch conditions of the vehicle may also be
`sensed based on sensing the linear or rotational relative
`displacement or displacement velocity of one or more of the
`suspension chassis components Which may include a linear
`height or travel sensor, a rotary height or travel sensor, a
`Wheel speed sensor used to look for a change in velocity, a
`steering Wheel position sensor, a steering Wheel velocity
`sensor and a driver heading command input from an elec
`tronic component that may include steer by Wire using a
`hand Wheel or joy stick.
`The roll and pitch conditions may also be sensed by
`sensing the force or torque associated With the loading
`condition of one or more suspension or chassis components
`including a pressure transducer in an active air suspension,
`a shock absorber sensor such as a load cell, a strain gauge,
`the steering system absolute or relative motor load, the
`steering system assist pressure, a tire laterally force sensor
`or sensors, a longitudinal tire force sensor, a vertical tire
`force sensor or a tire sideWall torsion sensor.
`The roll and pitch condition of the vehicle may also be
`established by one or more of the folloWing translational or
`rotational positions, velocities or accelerations of the vehicle
`including a roll gyro, the roll rate sensor 34, the yaW rate
`sensor 28, the lateral acceleration sensor 32, a vertical
`acceleration sensor 35, a vehicle longitudinal acceleration
`sensor 36, lateral or vertical speed sensors including a
`Wheel-based speed sensor, a radar-based speed sensor, a
`sonar-based speed sensor, a laser-based speed sensor or an
`optical-based speed sensor.
`Lateral acceleration, roll and pitch orientations and
`velocities may be obtained using a global positioning system
`(GPS) 41.
`The controller 26 may also be coupled to a lidar, radar, or
`sonar 42. The lidar, radar, or sonar 42 may be used to
`generate a velocity signal or relative velocity signal of an
`object. The radar or lidar may also be used to generate a
`trajectory signal of an object. LikeWise, the velocity of the
`vehicle in various directions may be obtained relative to a
`stationary object. A lidar, radar, or sonar sensor 42 may be
`mounted in various positions around the vehicle including
`the front, sides and/or rear. Multiple sensors 42 may also be
`employed in multiple locations to provide multiple infor
`mation from multiple positions of the vehicle. Such signals
`may also be used in a self parking condition.
`Controller 26 may also be coupled to a camera system 83
`having cameras 43a—43e. A stereo pair of cameras 43a, 43b
`may be mounted on the front of the vehicle to detect target
`objects in front of the vehicle, to measure the object siZe,
`range and relative velocity and to classify those objects into
`appropriate categories. Camera 43c may be mounted on the
`right side of the vehicle, camera 43d may be mounted on the
`left side of the vehicle, and camera 436 may be directed
`rearWard of the vehicle. Camera 436 may also include a
`stereo pair of cameras. All or some of the cameras may be
`used in a commercial embodiment. Also, a stereo pair of
`
`10
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`15
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`25
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`35
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`40
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`45
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`55
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`65
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`6
`cameras 43a, 43b may be replaced by a single camera (43a
`or 43b) depending on the roll and pitch conditions measured
`by the system. Various types of cameras Would be evident to
`those skilled in the art. Various types of cameras such as a
`CMOS-type camera or a CCD-type camera may be imple
`mented to generate various image signals. As Will be further
`described beloW, the various image signals may be analyZed
`to determine the various dynamic conditions of the vehicle.
`Controller 26 may also be coupled to an input device 44.
`Input device 44 may include a keyboard or other push button
`type device. Input device 44 may be used to enter trailer
`parameters or indicate to the controller a selection or other
`inputs.
`A reverse aid system 46 having at least one reverse aid
`sensor 48 may be coupled to controller 26. Reverse aid
`sensor 48 may be but is not limited to an ultrasonic sensor,
`a radar sensor, or a combination of the tWo. Reverse aid
`sensors 48 are typically located at several locations of the
`rear of the vehicle such as in the bumper. As Will be further
`described beloW, the reverse aid system 46 may be used to
`provide an indication as to the presence of a trailer and may
`also be used to generate a particular pattern With respect to
`the trailer to alloW the controller to have feedback With
`respect to the position of the trailer.
`A hand Wheel (also knoWn as “steering Wheel”) position
`sensor 50 may also be coupled to controller 26. Hand Wheel
`position sensor 50 provides controller 26 With a signal
`corresponding to the relative rotational position of the
`steering Wheel Within the vehicle. Various types of sensors
`include absolute sensors and position sensors using a center
`?nd algorithm (relative sensors). Relative sensors may use
`the center?nd algorithm to determine the position relative to
`a center position once the position is knoWn. Both types of
`sensors may provide a steering angle rate signal and/or a
`steering direction signal. For example, the steering direction
`may indicate aWay from or toWard a center position or end
`stop position.
`A hand Wheel torque sensor 52 may also be coupled to
`controller 26. Hand Wheel torque sensor 52 may be a sensor
`located Within the steering column for direct measurement.
`The steering torque may also be inferred from data available
`to the poWer steering system. The hand Wheel torque sensor
`52 generates a signal corresponding to the amount of torque
`placed on the hand Wheel (steering Wheel Within the
`vehicle).
`A mu sensor 54 may also be coupled to controller 26.
`Mu sensor 54 may be a direct sensor or, more likely, is a
`calculated value based on available inputs. Various systems
`such as a yaW control system for an anti-lock brake system
`may generate mu. Mu is an indication of the coefficient of
`friction of the surface on Which the vehicle is traveling. The
`mu sensor 54 may be used to generate a coefficient of
`friction for the vehicle or the coefficient of friction at more
`than one contact patch of the tire. Preferably, a mu is
`determined at each contact patch of each tire.
`A throttle sensor 56 may also be coupled to controller 26.
`Throttle sensor 56 may, for example, be a resistive sensor.
`Of course, other types of throttle sensors Would be evident
`to those skilled in the art. Throttle sensor 56 generates a
`signal corresponding to the position of the throttle of the
`vehicle. The throttle sensor 56 may give an indication as to
`the driver’s intention regarding acceleration. Throttle sensor
`may also be part of a drive-by-Wire type system. A throttle
`type sensor may also be used in electric vehicles and
`vehicles With diesel engines to determine the desire accel
`eration. These sensors may take the form of a pedal sensor.
`
`Petitioners Ex. 1004 Page 15
`
`

`

`US 6,959,970 B2
`
`7
`Avehicle load sensor 58 to sense the amount of Weight or
`payload Within the vehicle may also be coupled to controller
`26. Vehicle load sensor 58 may be one of various types of
`sensors including a suspension sensor. For example, one
`load sensor may be located at each suspension component.
`Load sensor 58 may, for example, be a pressure sensor in an
`air suspension. The load sensor 58 may also be a load cell.
`In any case, the vehicle load sensor 58 generates an elec
`trical signal corresponding to the load on the vehicle. One
`sensor or preferably one sensor for each corner of the vehicle
`may be used. The vehicle load may, for example, be the
`normal load at each corner of the vehicle. By knoWing the
`normal load at each corner of the vehicle, the total amount
`of loading on the vehicle may be determined.
`A suspension height sensor 60 may also be coupled to
`controller 26. Suspension height sensor 60 may be a sus
`pension height sensor located at each corner of the vehicle.
`Suspension height sensor 60 may also be part of an air
`suspension or other type of active suspension. Suspension
`height sensor 60 generates a height signal corresponding to
`the extension of the suspension. The suspension height
`sensor 60 may also be used to determine the vehicle load,
`normal load, and payload distribution, rather than using
`vehicle load sensor 58 described above. Suspension height
`sensor 60 may be one of various types of sensors including
`a laser, optical sensor, or the like.
`A transmission gear selector 62 may also be coupled to
`controller 26. Transmission gear selector 62 may, for
`example, comprise a shift lever that has the PRNDL selec
`tions corresponding to the park, reverse, neutral, regular
`drive and loW drive positions of the transmission. Also, an
`electrical signal may be generated in response to the position
`of the shift lever of a manual transmission.
`Amode selector 64 may also be coupled to controller 26.
`Mode selector 64 may select a driver selectable mode
`selector such as a manually activated mechanism (e.g., push
`button or the like) or a voice recognition system. Mode
`selector 64 may, for example, select a position that corre
`sponds to trailering. Also, mode selector may determine a
`park position indicating that the vehicle operator intends to
`park the vehicle. AU-turn position may also be selected. The
`mode selector may be used to enable or disable the system.
`A secondary steering actuator 66 such as a turn signal
`actuator, an additional stalk or push buttons may also be
`coupled to controller 26. The secondary steering actuator 66
`may also initiate the display of a turn signal indicator on the
`instrument panel of the vehicle. Secondary steering actuator
`66 may be used to steer a trailer of the vehicle as described
`beloW. For example, the vehicle or trailer may be directed in
`a particular direction corresponding to the secondary steer
`ing actuator direction.
`A display 68 may also be coupled to controller 26.
`Display 68 displays various types of display