US20030171869A1 - Torque management based traction control system - Google Patents
Torque management based traction control system Download PDFInfo
- Publication number
- US20030171869A1 US20030171869A1 US10/091,872 US9187202A US2003171869A1 US 20030171869 A1 US20030171869 A1 US 20030171869A1 US 9187202 A US9187202 A US 9187202A US 2003171869 A1 US2003171869 A1 US 2003171869A1
- Authority
- US
- United States
- Prior art keywords
- drive line
- determining
- power train
- torque
- drive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/17—Using electrical or electronic regulation means to control braking
- B60T8/175—Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K28/00—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions
- B60K28/10—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions responsive to conditions relating to the vehicle
- B60K28/16—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions responsive to conditions relating to the vehicle responsive to, or preventing, skidding of wheels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2510/00—Input parameters relating to a particular sub-units
- B60W2510/06—Combustion engines, Gas turbines
- B60W2510/0638—Engine speed
- B60W2510/0652—Speed change rate
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2710/00—Output or target parameters relating to a particular sub-units
- B60W2710/06—Combustion engines, Gas turbines
- B60W2710/0666—Engine torque
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D2250/00—Engine control related to specific problems or objectives
- F02D2250/18—Control of the engine output torque
Definitions
- the present invention relates generally to vehicle traction control systems and more particularly to a vehicle traction control system that controls the acceleration of any one of the vehicle, the vehicle driveline and the vehicle power train by comparing an actual acceleration value to a predicted maximum.
- Prior attempts to limit wheel slip typically employ a scheme that transfers torque from one or more of the slipping wheels to one or more of the non-slipping wheels.
- torque management schemes such as this are known to immediately reduce the magnitude by which the slipping wheel or wheels are slipping, the transfer of the excess torque to a non-slipping wheel can, at times, render the non-slipping wheels more susceptible to slip. This is particularly true when the vehicle is being operated on a surface with a relatively low coefficient of friction, such as on ice.
- the present invention provides a method for abating wheel slip in a vehicle having a power train and a drive line.
- the method includes the steps of: determining an actual angular acceleration ( ⁇ a ) of a portion of the drive line; determining a maximum predicted acceleration ( ⁇ p ) of the portion of the drive line; determining the existence of a wheel slip condition based on ⁇ a and ⁇ p ; if a wheel slip condition is occurring, determining an amount of excess torque (T x ) that is being delivered to the drive line; and reducing an amount of torque that is being delivered to the drive line by an amount (T er ) that is based on the value of T x .
- FIG. 1 is a perspective view of a vehicle having a traction control system constructed in accordance with the teachings of the present invention
- FIG. 2 is a schematic illustration of the vehicle of FIG. 1;
- FIG. 3 is a schematic illustration in flow chart form of the methodology of the present invention.
- FIGS. 4A and B are plots illustrating the effectiveness of the traction control system and methodology of the present invention.
- a vehicle 10 is illustrated to include a traction control system 12 that is constructed in accordance with the teachings of the present invention.
- the vehicle 10 which is illustrated to have a two-wheel drive configuration, conventionally includes a body 14 , a power train 18 and a drive line 20 .
- a body 14 conventionally includes a body 14 , a power train 18 and a drive line 20 .
- the teachings of the present invention may be applied to vehicles having other types of drive lines, including those having more than two drive wheels.
- the power train 18 and the drive line 20 are conventional in their construction and as such, need not be discussed in significant detail.
- the power train 18 includes a propulsion source, such as an internal combustion engine 22 , a torque converter 24 and a transmission 26 , while the drive line 20 includes a prop shaft 28 , a rear axle assembly 30 and a pair of drive wheels 32 .
- a propulsion source such as an internal combustion engine 22
- a torque converter 24 and a transmission 26
- the drive line 20 includes a prop shaft 28 , a rear axle assembly 30 and a pair of drive wheels 32 .
- the engine 22 conventionally transmits rotary power via an output shaft (not specifically shown) into the torque converter 24 , where the rotary output of the engine 22 is multiplied in a predetermined manner.
- the torque converter 24 is operable for multiplying the magnitude of a torsional load input to the transmission 26 via a transmission input shaft 26 a .
- the transmission 26 conventionally includes a plurality of gear ratios that are selectively engagable to alter the speed ratio between the transmission input shaft 26 a and a transmission output shaft 26 b .
- Rotary power output from the transmission 26 is delivered to the drive line 20 for distribution to the drive wheels 32 .
- a differential assembly 30 a distributes the rotary power to the drive wheels 32 in a predetermined manner that is based on the construction of the differential assembly 30 a and the methodology by which it is operated.
- the traction control system 12 includes a controller 40 that is operably coupled to a plurality of sensors 42 that are located throughout the vehicle 10 .
- the plurality of sensors 42 are operable for generating sensor signals indicative of various vehicle characteristics that are relevant to determine whether excess torque is being delivered by the drive line 20 , as well as the extent to which excess torque is being supplied.
- Such characteristics may include, for example, the rotational speed of a portion of the power train 18 , such as the engine crankshaft (not specifically shown), the turbine (not specifically shown) of the torque converter 24 or the transmission input shaft 26 a , and the rotational speed of a portion of the drive line 20 , such as the drive wheels 32 or the prop shaft 28 .
- the sensor signals that are generated by the plurality of sensors 42 are transmitted to the controller 40 , either directly or via a network or data bus.
- the controller 40 may be integrated into an existing controller within the vehicle 10 (e.g., engine controller, transmission controller, body controller, anti-lock brake controller) which are commonly integrated into modern vehicles, or may be a discrete unit.
- T o ( I o )( ⁇ a ) ⁇ T rl Equation 1
- T rl is the torque that is necessary to overcome the road load
- ⁇ a is the angular acceleration measured at some point in the drive line 20
- To is the magnitude of the torque that is provided to the drive line 20 , such as the torque output from the transmission output shaft 26 b.
- the value T o is typically employed in the control of the engine 22 , torque converter 24 and/or transmission 26 and as such, is typically either calculated or derived from variables that include the rate at which the engine 22 is being fueled, the engine speed, the operational state of the torque converter, the active gear ratio, etc.
- the value ⁇ a may be calculated based on sensor signals from sensors that sense the speed of the prop shaft 28 or axle shafts 30 b , for example.
- the value ⁇ a is calculated from a sensor signal produced by a speed sensor 42 a that monitors the rotational speed of the transmission output shaft 26 b . While the transmission output shaft 26 b has been characterized as being part of the power train 18 , those skilled in the art will understand that as the transmission output shaft 26 b and the prop shaft 28 rotate at the same rotational speed, a dedicated speed sensor for sensing the speed of the prop shaft 28 is not necessary.
- inertia reflected at the point of measure, I o is dependent upon the mass of the vehicle 10 and as such, tends to be constant over relatively short periods of time. It is presently preferred that the value I o be dynamically calculated (e.g., each time the ignition key is turned to “start” or each time the transmission 26 is shifted from “park” into a forward gear ratio setting, such as “drive”) so as to better reflect the actual inertia of the vehicle 10 .
- a forward gear ratio setting such as “drive”
- the value of T rl is calculatable under a non-slip condition.
- the value T rl includes friction, tire rolling resistance, aerodynamic drag and considerations for the grade upon which the vehicle 10 is operating and as such, the value T rl tends to be significant, particularly when the vehicle 10 is traveling at relatively high speeds.
- T rl can be assumed to be equal to zero (0), permitting the calculation of the maximum predicted acceleration of the drive line 20 from the equation:
- ⁇ p is the maximum predicted angular acceleration of the portion of the drive line 20 (which, in the example provided, is the maximum predicted angular acceleration of the prop shaft 28 and the transmission output shaft 26 b ).
- ⁇ s is the angular acceleration contributing to wheel slip.
- ⁇ s is negative (i.e., when ⁇ a is less than ⁇ p )
- ⁇ s is positive (i.e., when ⁇ a is greater than ⁇ p )
- ⁇ s is the direct result of excess torque is being delivered to the drive line 20 .
- Equation 3 Since the angular acceleration due to wheel slip ( ⁇ s ) is known from Equation 3, the magnitude of the excess torque that is delivered to the drive line 20 (e.g., the prop shaft 28 /transmission output shaft 26 b ) may be calculated through the equation:
- the value I d is the reflected inertia of the drive line components (including tires, but excluding vehicle mass) 20 , which is a known constant, and the value of T x is the excess torque delivered to the drive line 20 .
- T x the value of T x being known from Equation 4
- T er the value of the torque reduction at the engine 22
- T er the value of the torque reduction at the engine 22
- T er [( SF )( T x )]/[( GR )( STR )] Equation 11
- the value of GR is the gear ratio of the transmission 26 (i.e., the speed ratio between the transmission input shaft 26 a and the transmission output shaft.
- the value of STR is the stall torque ratio of the torque converter 24 .
- the stall torque ratio is the output torque of the torque converter 24 divided by the input torque of the torque converter 24 .
- the value of SF is a factor that is greater than 1.0 which is employed to control the aggressiveness with which a wheel slip condition is abated.
- a value of about 1.1 to about 1.25 may be employed to initiate a reduction in torque to the drive line 20 that would bring the value of T o well below that required to produce the predicted acceleration to thereby ensure that the wheel slip condition was fully abated.
- the actual value of SF preferably also takes into account concerns for the “driveability” of the vehicle 10 and the anticipated skill level of the driver (which tend to drive the value of SF closer to 1.0) and for the momentum of the engine flywheel (which tends to drive the value of SF further from 1.0).
- the value of T er is delivered to the engine controller 22 a (typically via a data bus) to reduce the amount of torque that is being produced by the engine and thereby inhibit the wheel slip condition.
- the methodology of the present invention is schematically illustrated in flowchart form.
- the methodology begins at block 78 and progresses to block 80 where inertia values I o and I d are initialized from the appropriate source.
- the value of T er is set to zero at this point to discontinue any previous torque management.
- the methodology then proceeds to block 86 .
- the methodology calculates values for T o , ( ⁇ a , and ⁇ p . The methodology then proceeds to decision block 88 .
- decision block 88 the methodology determines whether ⁇ a is greater than ⁇ p . If ⁇ a is not greater than ⁇ p , then slip is not detected and the methodology proceeds to decision block 94 where it is determined if the torque management request is still active. If ⁇ a is greater than ⁇ p (indicating that wheel slip is occurring), the methodology proceeds to block 90 .
- the methodology calculates ⁇ s , T x and T er , identifying the amount of slip and necessary reduction in engine torque. The methodology then proceeds to block 92 .
- the methodology causes the engine controller 22 a to implement a reduction in engine torque corresponding in magnitude to the previously calculated T er so as to abate the wheel slip condition. The methodology then loops back to block 86 .
- decision block 94 the methodology determines if T er is greater than zero (0). If the value of T er is not greater than zero, no torque reduction is active, so the methodology loops back to block 86 without requesting torque reduction. If the value of T er is greater than zero in decision block 94 , torque management is still active and the methodology proceeds to block 98 .
- the methodology reduces the value of T er in a predetermined manner.
- the methodology may set T er to zero to permit the power train 18 to provide “full” torque to the drive line 20 . It is presently preferred, however, that the methodology gradually decrease the value of T er so as to guard against the occurrence of a second wheel slip condition.
- the amount by which T er is reduced may be, for example, a fixed, predetermined rate, a rate that is based on the initial value of T er , or an amount that is based on the present value of T er .
- the methodology then continues to block 92 where the actual torque reduction is implemented.
- FIG. 4 is a plot that illustrating the effectiveness of the traction control system 12 of the present invention.
- the plot identified by reference numeral 200 illustrates the operation of the vehicle 10 with the traction control system 12 in a disabled or non-operative condition.
- the slip event is readily identified by the large difference between actual 204 and predicted 206 acceleration and the resulting peak in output shaft speed 208 . As traction improves, output shaft speed decreases to match vehicle speed.
- the plot identified by reference numeral 202 illustrates the operation of the vehicle 10 with the traction control system 12 in an enabled or operative condition.
- a slip event is identified by the marked difference between actual 210 and predicted 212 acceleration.
- the amount of torque reduction 212 required to abate slip is calculated and implemented.
- the engine torque reduction value 214 is slowly reduced.
- a second slip event 218 is clearly demonstrated in this example and the traction control system 12 quickly responds to abate this slip. It should be noted the output shaft speed trace 216 reveals no peaks characteristic of a slip event.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- Transportation (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
Abstract
Description
- The present invention relates generally to vehicle traction control systems and more particularly to a vehicle traction control system that controls the acceleration of any one of the vehicle, the vehicle driveline and the vehicle power train by comparing an actual acceleration value to a predicted maximum.
- Conventional automotive vehicles are typically equipped with a power train for producing a source of rotary power and a driveline for transmitting rotary power to a set of vehicle drive wheels. While the modem power train configurations have, for the most part, proven themselves to be satisfactory for producing rotary power, several limitations have been noted. One such limitation of the modern power train configurations is their ability, on occasion, to supply too much rotary power to one or more of the vehicle drive wheels to thereby cause wheel slip which renders the vehicle somewhat more difficult to control.
- Prior attempts to limit wheel slip typically employ a scheme that transfers torque from one or more of the slipping wheels to one or more of the non-slipping wheels. Although torque management schemes such as this are known to immediately reduce the magnitude by which the slipping wheel or wheels are slipping, the transfer of the excess torque to a non-slipping wheel can, at times, render the non-slipping wheels more susceptible to slip. This is particularly true when the vehicle is being operated on a surface with a relatively low coefficient of friction, such as on ice.
- Accordingly, there is a need in the art for an improved traction control system and method for controlling the torque that is transmitted to the drive wheels of a vehicle.
- In one preferred form, the present invention provides a method for abating wheel slip in a vehicle having a power train and a drive line. The method includes the steps of: determining an actual angular acceleration (αa) of a portion of the drive line; determining a maximum predicted acceleration (αp) of the portion of the drive line; determining the existence of a wheel slip condition based on αa and αp; if a wheel slip condition is occurring, determining an amount of excess torque (Tx) that is being delivered to the drive line; and reducing an amount of torque that is being delivered to the drive line by an amount (Ter) that is based on the value of Tx.
- Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
- The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
- FIG. 1 is a perspective view of a vehicle having a traction control system constructed in accordance with the teachings of the present invention;
- FIG. 2 is a schematic illustration of the vehicle of FIG. 1;
- FIG. 3 is a schematic illustration in flow chart form of the methodology of the present invention; and
- FIGS. 4A and B are plots illustrating the effectiveness of the traction control system and methodology of the present invention.
- With reference to FIGS. 1 and 2, a
vehicle 10 is illustrated to include atraction control system 12 that is constructed in accordance with the teachings of the present invention. Thevehicle 10, which is illustrated to have a two-wheel drive configuration, conventionally includes abody 14, apower train 18 and adrive line 20. Those skilled in the art will understand that the teachings of the present invention may be applied to vehicles having other types of drive lines, including those having more than two drive wheels. In the example provided, thepower train 18 and thedrive line 20 are conventional in their construction and as such, need not be discussed in significant detail. Briefly, thepower train 18 includes a propulsion source, such as aninternal combustion engine 22, atorque converter 24 and atransmission 26, while thedrive line 20 includes aprop shaft 28, arear axle assembly 30 and a pair ofdrive wheels 32. - The
engine 22 conventionally transmits rotary power via an output shaft (not specifically shown) into thetorque converter 24, where the rotary output of theengine 22 is multiplied in a predetermined manner. Thetorque converter 24 is operable for multiplying the magnitude of a torsional load input to thetransmission 26 via atransmission input shaft 26 a. Thetransmission 26 conventionally includes a plurality of gear ratios that are selectively engagable to alter the speed ratio between thetransmission input shaft 26 a and a transmission output shaft 26 b. Rotary power output from thetransmission 26 is delivered to thedrive line 20 for distribution to thedrive wheels 32. In this regard, power is transmitted through theprop shaft 28 to therear axle assembly 30 where adifferential assembly 30 a distributes the rotary power to thedrive wheels 32 in a predetermined manner that is based on the construction of thedifferential assembly 30 a and the methodology by which it is operated. - The
traction control system 12 includes acontroller 40 that is operably coupled to a plurality ofsensors 42 that are located throughout thevehicle 10. As will be better understood from the discussion below, the plurality ofsensors 42 are operable for generating sensor signals indicative of various vehicle characteristics that are relevant to determine whether excess torque is being delivered by thedrive line 20, as well as the extent to which excess torque is being supplied. Such characteristics may include, for example, the rotational speed of a portion of thepower train 18, such as the engine crankshaft (not specifically shown), the turbine (not specifically shown) of thetorque converter 24 or thetransmission input shaft 26 a, and the rotational speed of a portion of thedrive line 20, such as thedrive wheels 32 or theprop shaft 28. The sensor signals that are generated by the plurality ofsensors 42 are transmitted to thecontroller 40, either directly or via a network or data bus. Thecontroller 40 may be integrated into an existing controller within the vehicle 10 (e.g., engine controller, transmission controller, body controller, anti-lock brake controller) which are commonly integrated into modern vehicles, or may be a discrete unit. - Under normal vehicle operating conditions, the torque transmitted through the drive line is expressed as acceleration of the vehicle inertia or absorbed losses known as road load. Setting the frame of reference to the transmission output shaft54:
- T o=(I o)(αa)−T rl Equation 1
- where Trl is the torque that is necessary to overcome the road load; αa is the angular acceleration measured at some point in the
drive line 20; and To is the magnitude of the torque that is provided to thedrive line 20, such as the torque output from the transmission output shaft 26 b. - The value To is typically employed in the control of the
engine 22,torque converter 24 and/ortransmission 26 and as such, is typically either calculated or derived from variables that include the rate at which theengine 22 is being fueled, the engine speed, the operational state of the torque converter, the active gear ratio, etc. - The value αa may be calculated based on sensor signals from sensors that sense the speed of the
prop shaft 28 oraxle shafts 30 b, for example. In the particular embodiment provided, the value αa is calculated from a sensor signal produced by aspeed sensor 42 a that monitors the rotational speed of the transmission output shaft 26 b. While the transmission output shaft 26 b has been characterized as being part of thepower train 18, those skilled in the art will understand that as the transmission output shaft 26 b and theprop shaft 28 rotate at the same rotational speed, a dedicated speed sensor for sensing the speed of theprop shaft 28 is not necessary. - The value of inertia reflected at the point of measure, Io is dependent upon the mass of the
vehicle 10 and as such, tends to be constant over relatively short periods of time. It is presently preferred that the value Io be dynamically calculated (e.g., each time the ignition key is turned to “start” or each time thetransmission 26 is shifted from “park” into a forward gear ratio setting, such as “drive”) so as to better reflect the actual inertia of thevehicle 10. Commonly assigned U.S. Pat. No. 5,738,605, entitled “Anti-hunt Strategy for an Automatic Transmission”, and U.S. Pat. No. 6,067,495, entitled “Acceleration Based Shift Strategy for an Automatic Transmission”, which are hereby incorporated by reference as if fully set forth herein, detail one method by which the value Io may be calculated. - With the values To, Io, and αa being known, the value of Trl is calculatable under a non-slip condition. The value Trl includes friction, tire rolling resistance, aerodynamic drag and considerations for the grade upon which the
vehicle 10 is operating and as such, the value Trl tends to be significant, particularly when thevehicle 10 is traveling at relatively high speeds. - For identification of slip condition, Trl can be assumed to be equal to zero (0), permitting the calculation of the maximum predicted acceleration of the
drive line 20 from the equation: - αp =T o÷(I o)
Equation 2 - where αp is the maximum predicted angular acceleration of the portion of the drive line 20 (which, in the example provided, is the maximum predicted angular acceleration of the
prop shaft 28 and the transmission output shaft 26 b). - With αa and αp known, a value for the angular acceleration directly contributing to wheel slip, αs, is calculated from the equation:
- αs=αa−αp Equation 3
- where αs, is the angular acceleration contributing to wheel slip. When αs is negative (i.e., when αa is less than αp), there is no wheel slip. When αs is positive (i.e., when αa is greater than αp), a wheel slip event is occurring, the direct result of excess torque is being delivered to the
drive line 20. - Since the angular acceleration due to wheel slip (αs) is known from
Equation 3, the magnitude of the excess torque that is delivered to the drive line 20 (e.g., theprop shaft 28/transmission output shaft 26 b) may be calculated through the equation: - T x=(αs)(I d) Equation 4
- where the value Id is the reflected inertia of the drive line components (including tires, but excluding vehicle mass) 20, which is a known constant, and the value of Tx is the excess torque delivered to the
drive line 20. - With the value of Tx being known from Equation 4, a reduction in the torque output by the
engine 22 can be determined to inhibit wheel slip. The value of the torque reduction at the engine 22 (Ter) necessarily accounts for the torque multiplication/speed reduction effects of thetorque converter 24 and thetransmission 26 and as such, is highly dependent upon the configuration of thepower train 18. Given that the value Tx is known, the calculation of Ter is well within the capabilities of one skilled in the art and as such, need not be discussed in any significant detail herein. - In the particular example provided, the value of Ter is calculated through the equation:
- T er=[(SF)(T x)]/[(GR)(STR)] Equation 11
- The value of GR is the gear ratio of the transmission26 (i.e., the speed ratio between the
transmission input shaft 26 a and the transmission output shaft. The value of STR is the stall torque ratio of thetorque converter 24. The stall torque ratio is the output torque of thetorque converter 24 divided by the input torque of thetorque converter 24. The value of SF is a factor that is greater than 1.0 which is employed to control the aggressiveness with which a wheel slip condition is abated. In general, it is desirable to aggressively abate situations where wheel slip may occur and as such, a value of about 1.1 to about 1.25 may be employed to initiate a reduction in torque to thedrive line 20 that would bring the value of To well below that required to produce the predicted acceleration to thereby ensure that the wheel slip condition was fully abated. The actual value of SF, however, preferably also takes into account concerns for the “driveability” of thevehicle 10 and the anticipated skill level of the driver (which tend to drive the value of SF closer to 1.0) and for the momentum of the engine flywheel (which tends to drive the value of SF further from 1.0). The value of Ter is delivered to theengine controller 22 a (typically via a data bus) to reduce the amount of torque that is being produced by the engine and thereby inhibit the wheel slip condition. - With reference to FIG. 3, the methodology of the present invention is schematically illustrated in flowchart form. The methodology begins at
block 78 and progresses to block 80 where inertia values Io and Id are initialized from the appropriate source. The value of Ter is set to zero at this point to discontinue any previous torque management. The methodology then proceeds to block 86. - In
block 86, the methodology calculates values for To, (αa, and αp. The methodology then proceeds todecision block 88. - In
decision block 88 the methodology determines whether αa is greater than αp. If αa is not greater than αp, then slip is not detected and the methodology proceeds todecision block 94 where it is determined if the torque management request is still active. If αa is greater than αp (indicating that wheel slip is occurring), the methodology proceeds to block 90. - In
block 90, the methodology calculates αs, Tx and Ter, identifying the amount of slip and necessary reduction in engine torque. The methodology then proceeds to block 92. - In
block 92, the methodology causes theengine controller 22 a to implement a reduction in engine torque corresponding in magnitude to the previously calculated Ter so as to abate the wheel slip condition. The methodology then loops back to block 86. - In
decision block 94, the methodology determines if Ter is greater than zero (0). If the value of Ter is not greater than zero, no torque reduction is active, so the methodology loops back to block 86 without requesting torque reduction. If the value of Ter is greater than zero indecision block 94, torque management is still active and the methodology proceeds to block 98. - In
block 98, the methodology reduces the value of Ter in a predetermined manner. The methodology may set Ter to zero to permit thepower train 18 to provide “full” torque to thedrive line 20. It is presently preferred, however, that the methodology gradually decrease the value of Ter so as to guard against the occurrence of a second wheel slip condition. The amount by which Ter is reduced may be, for example, a fixed, predetermined rate, a rate that is based on the initial value of Ter, or an amount that is based on the present value of Ter. The methodology then continues to block 92 where the actual torque reduction is implemented. - FIG. 4 is a plot that illustrating the effectiveness of the
traction control system 12 of the present invention. The plot identified byreference numeral 200 illustrates the operation of thevehicle 10 with thetraction control system 12 in a disabled or non-operative condition. The slip event is readily identified by the large difference between actual 204 and predicted 206 acceleration and the resulting peak inoutput shaft speed 208. As traction improves, output shaft speed decreases to match vehicle speed. - The plot identified by
reference numeral 202 illustrates the operation of thevehicle 10 with thetraction control system 12 in an enabled or operative condition. In this example a slip event is identified by the marked difference between actual 210 and predicted 212 acceleration. The amount oftorque reduction 212 required to abate slip is calculated and implemented. Afteractual acceleration 210 is reduced to the level of predictedacceleration 212, the enginetorque reduction value 214 is slowly reduced. Asecond slip event 218 is clearly demonstrated in this example and thetraction control system 12 quickly responds to abate this slip. It should be noted the outputshaft speed trace 216 reveals no peaks characteristic of a slip event. - While the invention has been described in the specification and illustrated in the drawings with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention as defined in the claims. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment illustrated by the drawings and described in the specification as the best mode presently contemplated for carrying out this invention, but that the invention will include any embodiments falling within the foregoing description and the appended claims.
Claims (19)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/091,872 US6615126B1 (en) | 2002-03-05 | 2002-03-05 | Torque management based traction control system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/091,872 US6615126B1 (en) | 2002-03-05 | 2002-03-05 | Torque management based traction control system |
Publications (2)
Publication Number | Publication Date |
---|---|
US6615126B1 US6615126B1 (en) | 2003-09-02 |
US20030171869A1 true US20030171869A1 (en) | 2003-09-11 |
Family
ID=27765367
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/091,872 Expired - Lifetime US6615126B1 (en) | 2002-03-05 | 2002-03-05 | Torque management based traction control system |
Country Status (1)
Country | Link |
---|---|
US (1) | US6615126B1 (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080195282A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Perception model for trajectory following autonomous and human augmented steering control |
US20080195293A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Perception model for trajectory following autonomous and human augmented speed control |
US20080195281A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Human perception model for steering performance |
US20080195569A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Human perception model for speed control performance |
US20130345916A1 (en) * | 2011-03-07 | 2013-12-26 | Takayoshi Ozaki | Electric vehicle |
US20140231160A1 (en) * | 2013-02-15 | 2014-08-21 | Sumitomo Heavy Industries, Ltd. | Motor drive apparatus for electric forklift and electric forklift adopting the same |
US8886381B2 (en) | 2011-03-07 | 2014-11-11 | Ntn Corporation | Electric vehicle |
WO2015074822A1 (en) * | 2013-11-20 | 2015-05-28 | Robert Bosch Gmbh | Method, device, and computer program for operating a power train of a motor vehicle |
EP2783906A4 (en) * | 2011-11-24 | 2016-05-11 | Ntn Toyo Bearing Co Ltd | Electric vehicle control device |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003293823A (en) * | 2002-03-27 | 2003-10-15 | Robert Bosch Gmbh | Drive slip control method and device |
US6810318B2 (en) * | 2002-09-13 | 2004-10-26 | General Motors Corporation | Drive torque transfer scheme |
US7050899B2 (en) * | 2004-03-24 | 2006-05-23 | Autotronic Controls Corporation | Slew rate revlimiter |
US7341541B2 (en) | 2005-10-11 | 2008-03-11 | Chrysler Llc | Method to reduce backlash in a drive train |
US7641014B2 (en) * | 2006-01-31 | 2010-01-05 | Robert Bosch Gmbh | Traction control system and method |
US7957881B2 (en) * | 2006-10-04 | 2011-06-07 | Toyota Jidosha Kabushiki Kaisha | Vehicle and method of controlling driving force for the vehicle based on detected slip of the drive wheel |
DE102007052749A1 (en) * | 2007-11-06 | 2009-05-07 | Robert Bosch Gmbh | Method for detecting wheel slip |
US8554440B1 (en) | 2010-01-05 | 2013-10-08 | Davis Intellectual Properties LLC | Electronic traction control |
JP6223717B2 (en) * | 2013-06-03 | 2017-11-01 | Ntn株式会社 | Electric vehicle slip control device |
US10495010B2 (en) | 2016-08-16 | 2019-12-03 | Dana Heavy Vehicle Systems Group, Llc | Damage protection for multi-function axle |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3837862C2 (en) | 1988-11-08 | 1993-09-30 | Gkn Automotive Ag | Device for controlling limited slip differentials |
US5092434A (en) * | 1991-01-30 | 1992-03-03 | Borg-Warner Automotive, Inc | Control strategies for a dual range infinitely variable transmission |
US5213177A (en) | 1991-12-19 | 1993-05-25 | Zexel-Gleason Usa, Inc. | Traction control system responsive to wheel speed fluctuations |
DE4315885C1 (en) | 1993-05-12 | 1994-11-03 | Daimler Benz Ag | Torque adjustment procedure |
DE19546554C1 (en) | 1995-12-13 | 1997-02-27 | Daimler Benz Ag | Procedure and device for controlling IC engine torque |
US5833572A (en) | 1997-05-05 | 1998-11-10 | Chrysler Corporation | Torque management for garage shifts |
DE19803387C1 (en) | 1998-01-29 | 1999-03-18 | Daimler Benz Ag | Load output setting method for automobile i.c. engine |
EP0976922B1 (en) | 1998-07-29 | 2006-01-04 | DaimlerChrysler AG | Method for torque adjustment |
US6334832B1 (en) * | 2000-05-31 | 2002-01-01 | Warn Industries, Inc. | Control for vehicle differential |
-
2002
- 2002-03-05 US US10/091,872 patent/US6615126B1/en not_active Expired - Lifetime
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8510034B2 (en) | 2007-02-12 | 2013-08-13 | Deere & Company | Perception model for trajectory following autonomous and human augmented steering control |
US8498796B2 (en) | 2007-02-12 | 2013-07-30 | Deere & Company | Perception model for trajectory following autonomous and human augmented speed control |
US20080195282A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Perception model for trajectory following autonomous and human augmented steering control |
US20080195569A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Human perception model for speed control performance |
US7769512B2 (en) | 2007-02-12 | 2010-08-03 | Deere & Company | Vehicle steering control method and performance |
US7895135B2 (en) * | 2007-02-12 | 2011-02-22 | Deere & Company | Human perception model for speed control performance |
US8195364B2 (en) | 2007-02-12 | 2012-06-05 | Deere & Company | Perception model for trajectory following autonomous and human augmented steering control |
US20080195293A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Perception model for trajectory following autonomous and human augmented speed control |
US20080195281A1 (en) * | 2007-02-12 | 2008-08-14 | William Robert Norris | Human perception model for steering performance |
US9114711B2 (en) | 2011-03-07 | 2015-08-25 | Ntn Corporation | Electric vehicle |
US8843291B2 (en) * | 2011-03-07 | 2014-09-23 | Ntn Corporation | Electric vehicle |
US20130345916A1 (en) * | 2011-03-07 | 2013-12-26 | Takayoshi Ozaki | Electric vehicle |
US8886381B2 (en) | 2011-03-07 | 2014-11-11 | Ntn Corporation | Electric vehicle |
US9296291B2 (en) | 2011-03-07 | 2016-03-29 | Ntn Corporation | Electric vehicle |
US9550435B2 (en) | 2011-11-24 | 2017-01-24 | Ntn Corporation | Electric vehicle control device |
EP2783906A4 (en) * | 2011-11-24 | 2016-05-11 | Ntn Toyo Bearing Co Ltd | Electric vehicle control device |
US9145287B2 (en) * | 2013-02-15 | 2015-09-29 | Sumitomo Heavy Industries, Ltd. | Motor drive apparatus for electric forklift and electric forklift adopting the same |
US20140231160A1 (en) * | 2013-02-15 | 2014-08-21 | Sumitomo Heavy Industries, Ltd. | Motor drive apparatus for electric forklift and electric forklift adopting the same |
WO2015074822A1 (en) * | 2013-11-20 | 2015-05-28 | Robert Bosch Gmbh | Method, device, and computer program for operating a power train of a motor vehicle |
Also Published As
Publication number | Publication date |
---|---|
US6615126B1 (en) | 2003-09-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6615126B1 (en) | Torque management based traction control system | |
US7585250B2 (en) | Method for operating a motor vehicle | |
US4999778A (en) | Method and apparatus for determining slip thresholds for a propulsion slip control system of a motor vehicle | |
US7072756B2 (en) | Vehicle driving force control apparatus | |
US6882921B2 (en) | Traction control algorithm for vehicle operation upon deformable road surfaces | |
CN110775061B (en) | Control method and device for inhibiting slip of front wheel of four-wheel drive vehicle and four-wheel drive power automobile | |
US5927422A (en) | Method and apparatus for correcting drive wheel slip | |
US8234050B2 (en) | Torque limiting clutch with engine torque management for thermal protection | |
EP0435833A1 (en) | A method and a system for controlling traction in motor vehicles with mechanical gearboxes | |
EP1125783B1 (en) | Method for controlling an automatic transmission | |
KR100374430B1 (en) | Traction slip controller | |
US8398180B2 (en) | Method of braking a vehicle | |
JPH11107803A (en) | Driving slip control method and device in automobile | |
JP3536523B2 (en) | Driving force control device for vehicles | |
US20190337518A1 (en) | Method for controlling a drive motor in a motor vehicle | |
US20100076660A1 (en) | Vehicle traction control system | |
JP2002538388A (en) | Vehicle control method | |
US20020161504A1 (en) | Method and device for adjusting the braking and/or drive effects on wheel of motor vehicles | |
US20090012690A1 (en) | Vehicle Descent Control | |
US6577944B1 (en) | Traction control system | |
US7124850B2 (en) | Four wheel drive assembly and a method for utilizing the same | |
US20030154013A1 (en) | Traction distribution control system for four-wheel drive vehicle | |
US20090319146A1 (en) | Traction control system for diesel powered vehicles | |
US6512972B1 (en) | Torque distribution on four wheel drive vehicles | |
JP4551039B2 (en) | Braking force control device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DAIMLERCHRYSLER CORPORATION, MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:POTTER, KENNETH J;CELINI, DEAN A.;DENTON, DANIEL S;REEL/FRAME:012809/0083;SIGNING DATES FROM 20020222 TO 20020402 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
AS | Assignment |
Owner name: WILMINGTON TRUST COMPANY, DELAWARE Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - FIRST PRIORITY;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:019773/0001 Effective date: 20070803 Owner name: WILMINGTON TRUST COMPANY,DELAWARE Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - FIRST PRIORITY;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:019773/0001 Effective date: 20070803 |
|
AS | Assignment |
Owner name: WILMINGTON TRUST COMPANY, DELAWARE Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - SECOND PRIORITY;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:019767/0810 Effective date: 20070803 Owner name: WILMINGTON TRUST COMPANY,DELAWARE Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - SECOND PRIORITY;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:019767/0810 Effective date: 20070803 |
|
AS | Assignment |
Owner name: DAIMLERCHRYSLER COMPANY LLC, MICHIGAN Free format text: CHANGE OF NAME;ASSIGNOR:DAIMLERCHRYSLER CORPORATION;REEL/FRAME:021779/0793 Effective date: 20070329 |
|
AS | Assignment |
Owner name: CHRYSLER LLC, MICHIGAN Free format text: CHANGE OF NAME;ASSIGNOR:DAIMLERCHRYSLER COMPANY LLC;REEL/FRAME:021826/0001 Effective date: 20070727 |
|
AS | Assignment |
Owner name: US DEPARTMENT OF THE TREASURY, DISTRICT OF COLUMBI Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - THIR;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:022259/0188 Effective date: 20090102 Owner name: US DEPARTMENT OF THE TREASURY,DISTRICT OF COLUMBIA Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS - THIR;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:022259/0188 Effective date: 20090102 |
|
AS | Assignment |
Owner name: CHRYSLER LLC, MICHIGAN Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:US DEPARTMENT OF THE TREASURY;REEL/FRAME:022902/0310 Effective date: 20090608 Owner name: CHRYSLER LLC,MICHIGAN Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:US DEPARTMENT OF THE TREASURY;REEL/FRAME:022902/0310 Effective date: 20090608 |
|
AS | Assignment |
Owner name: CHRYSLER LLC, MICHIGAN Free format text: RELEASE OF SECURITY INTEREST IN PATENT RIGHTS - FIRST PRIORITY;ASSIGNOR:WILMINGTON TRUST COMPANY;REEL/FRAME:022910/0498 Effective date: 20090604 Owner name: CHRYSLER LLC, MICHIGAN Free format text: RELEASE OF SECURITY INTEREST IN PATENT RIGHTS - SECOND PRIORITY;ASSIGNOR:WILMINGTON TRUST COMPANY;REEL/FRAME:022910/0740 Effective date: 20090604 Owner name: NEW CARCO ACQUISITION LLC, MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:022915/0001 Effective date: 20090610 Owner name: THE UNITED STATES DEPARTMENT OF THE TREASURY, DIST Free format text: SECURITY AGREEMENT;ASSIGNOR:NEW CARCO ACQUISITION LLC;REEL/FRAME:022915/0489 Effective date: 20090610 Owner name: CHRYSLER LLC,MICHIGAN Free format text: RELEASE OF SECURITY INTEREST IN PATENT RIGHTS - FIRST PRIORITY;ASSIGNOR:WILMINGTON TRUST COMPANY;REEL/FRAME:022910/0498 Effective date: 20090604 Owner name: CHRYSLER LLC,MICHIGAN Free format text: RELEASE OF SECURITY INTEREST IN PATENT RIGHTS - SECOND PRIORITY;ASSIGNOR:WILMINGTON TRUST COMPANY;REEL/FRAME:022910/0740 Effective date: 20090604 Owner name: NEW CARCO ACQUISITION LLC,MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CHRYSLER LLC;REEL/FRAME:022915/0001 Effective date: 20090610 Owner name: THE UNITED STATES DEPARTMENT OF THE TREASURY,DISTR Free format text: SECURITY AGREEMENT;ASSIGNOR:NEW CARCO ACQUISITION LLC;REEL/FRAME:022915/0489 Effective date: 20090610 |
|
AS | Assignment |
Owner name: CHRYSLER GROUP LLC, MICHIGAN Free format text: CHANGE OF NAME;ASSIGNOR:NEW CARCO ACQUISITION LLC;REEL/FRAME:022919/0126 Effective date: 20090610 Owner name: CHRYSLER GROUP LLC,MICHIGAN Free format text: CHANGE OF NAME;ASSIGNOR:NEW CARCO ACQUISITION LLC;REEL/FRAME:022919/0126 Effective date: 20090610 |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
AS | Assignment |
Owner name: CHRYSLER GROUP LLC, MICHIGAN Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:THE UNITED STATES DEPARTMENT OF THE TREASURY;REEL/FRAME:026343/0298 Effective date: 20110524 Owner name: CHRYSLER GROUP GLOBAL ELECTRIC MOTORCARS LLC, NORT Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:THE UNITED STATES DEPARTMENT OF THE TREASURY;REEL/FRAME:026343/0298 Effective date: 20110524 |
|
AS | Assignment |
Owner name: CITIBANK, N.A., NEW YORK Free format text: SECURITY AGREEMENT;ASSIGNOR:CHRYSLER GROUP LLC;REEL/FRAME:026404/0123 Effective date: 20110524 |
|
AS | Assignment |
Owner name: CITIBANK, N.A., NEW YORK Free format text: SECURITY AGREEMENT;ASSIGNOR:CHRYSLER GROUP LLC;REEL/FRAME:026435/0652 Effective date: 20110524 |
|
AS | Assignment |
Owner name: JPMORGAN CHASE BANK, N.A., ILLINOIS Free format text: SECURITY AGREEMENT;ASSIGNOR:CHRYSLER GROUP LLC;REEL/FRAME:032384/0640 Effective date: 20140207 |
|
FPAY | Fee payment |
Year of fee payment: 12 |
|
AS | Assignment |
Owner name: FCA US LLC, MICHIGAN Free format text: CHANGE OF NAME;ASSIGNOR:CHRYSLER GROUP LLC;REEL/FRAME:035553/0356 Effective date: 20141203 |
|
AS | Assignment |
Owner name: FCA US LLC, FORMERLY KNOWN AS CHRYSLER GROUP LLC, Free format text: RELEASE OF SECURITY INTEREST RELEASING SECOND-LIEN SECURITY INTEREST PREVIOUSLY RECORDED AT REEL 026426 AND FRAME 0644, REEL 026435 AND FRAME 0652, AND REEL 032384 AND FRAME 0591;ASSIGNOR:CITIBANK, N.A.;REEL/FRAME:037784/0001 Effective date: 20151221 |
|
AS | Assignment |
Owner name: FCA US LLC (FORMERLY KNOWN AS CHRYSLER GROUP LLC), Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:CITIBANK, N.A.;REEL/FRAME:042885/0255 Effective date: 20170224 |
|
AS | Assignment |
Owner name: FCA US LLC (FORMERLY KNOWN AS CHRYSLER GROUP LLC), Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:048177/0356 Effective date: 20181113 |