EP1311416A1 - Procede et dispositif pour determiner des grandeurs d'etat de vehicule - Google Patents

Procede et dispositif pour determiner des grandeurs d'etat de vehicule

Info

Publication number
EP1311416A1
EP1311416A1 EP00956417A EP00956417A EP1311416A1 EP 1311416 A1 EP1311416 A1 EP 1311416A1 EP 00956417 A EP00956417 A EP 00956417A EP 00956417 A EP00956417 A EP 00956417A EP 1311416 A1 EP1311416 A1 EP 1311416A1
Authority
EP
European Patent Office
Prior art keywords
wheel
vehicle
forces
variables
tire
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.)
Withdrawn
Application number
EP00956417A
Other languages
German (de)
English (en)
Inventor
Michael LATARNIK
Ulrich LÜDERS
Georg Roll
Thomas Raste
Rainer Oehler
Karl Izsak
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Continental Teves AG and Co OHG
Original Assignee
Continental Teves AG and Co OHG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE10039108A external-priority patent/DE10039108B4/de
Application filed by Continental Teves AG and Co OHG filed Critical Continental Teves AG and Co OHG
Publication of EP1311416A1 publication Critical patent/EP1311416A1/fr
Withdrawn legal-status Critical Current

Links

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
    • B60T8/1755—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve
    • B60T8/17551—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve determining control parameters related to vehicle stability used in the regulation, e.g. by calculations involving measured or detected parameters
    • 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
    • B60T8/1755—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve
    • B60T8/17554—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve specially adapted for enhancing stability around the vehicles longitudinal axle, i.e. roll-over prevention
    • 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
    • B60T2230/00—Monitoring, detecting special vehicle behaviour; Counteracting thereof
    • B60T2230/03—Overturn, rollover

Definitions

  • the invention relates to a method for determining vehicle state variables, in which at least one variable that is indicative of the vehicle tilting tendency about the vehicle longitudinal axis and is evaluated for determining control or regulating variables of a motor vehicle control system is evaluated according to the preamble of claim 1 and a device according to the preamble of claim 11.
  • Vehicles with a high center of gravity and soft suspension tend to tip around the longitudinal axis in extreme steering maneuvers.
  • the center of gravity with the respective state size requires a great deal of effort in the acquisition and evaluation of the signals indicative of the vehicle tipping tendency, which leads to a delay in the formation of the control or regulation size, the impending risk of tipping being recognized only after the signals have been correlated.
  • the object of the invention is to create a method and a device which are as fast as possible Reaction to a risk of tipping over is permitted by means of a regulating intervention.
  • At least one parameter (s) that is indicative of the tendency of the vehicle to tip over by continuously recording these measured variables on at least one inside of the curve from measured variables that were determined with the aid of tire or wheel force sensors and that reflect the tire or wheel lateral forces and / or the tire or wheel contact forces and -external vehicle wheel is determined and the determined direct tire or wheel forces themselves or variables derived therefrom, such as filtered variables, and / or signals formed with the inclusion of correction variables or values are used as control variables, a quick reaction to a risk of tipping is possible , because forces in the longitudinal and transverse or vertical directions can be easily calculated using the tire or wheel force sensors. Calculating these forces therefore only takes a short time.
  • these forces are therefore advisable to use precisely these forces as a parameter for a tendency of the vehicle to tip over, in order to be able to carry out a control intervention in the most direct way, in particular a braking intervention on the front wheel or the front wheels on the outside of the curve.
  • these forces also allow a risk of a vehicle tipping over to be predicted, since this process announces itself beforehand by lifting the wheels on the inside of the curve, ie losing their contact forces.
  • the inside front wheel or the inside rear wheel may be affected earlier.
  • the method for detecting impending tipping conditions in vehicles therefore preferably determines these states by monitoring the rare-force information on the inside and outside of the vehicle wheels via the direct tire or wheel forces themselves or signals derived therefrom.
  • the looming tipping situations are detected reliably and early with the help of tire or wheel force information.
  • This force information reflects the exact driving condition so that all parameters such as the height of the center of gravity, weight shift, state of the suspension, road condition etc. are included.
  • At least one associated tilt prevention threshold value is expediently determined for the at least one parameter.
  • the variable tilt prevention threshold can be dependent on the coefficient of friction, lateral acceleration, cornering radius and the like. the like can be individually assigned to each vehicle for each driving condition so that timely, situation-adapted, early detection of the risk of tipping is possible.
  • a risk of tipping is recognized if the difference in the lateral forces between the inside and outside wheel exceeds a threshold value which is a function of the lateral forces, the longitudinal forces and the vehicle speed, or a function of the lateral forces and their time derivatives, the longitudinal forces and the vehicle speed is.
  • this at least one tilt prevention threshold value is exceeded at certain points or over a defined period, preferably by the difference in lateral forces between the inside and outside wheel in successive or closely spaced control cycles, depending on the characteristic variable or the temporal gradient of the characteristic variable .
  • the risk of tipping is consequently considered to be recognized if at least one of the tipping prevention threshold values is exceeded over a defined period of time, that is to say by the lateral force differences of various control cycles which follow one another or are closely spaced in time.
  • a risk of tipping is still recognized if the difference in the lateral forces between the inside and outside wheel of any axle or both axles exceeds the tipping prevention threshold value selectively or over a longer period of time.
  • a risk of tipping is considered to be recognized if the temporal gradient of the difference between the lateral force of the inside and outside wheel of an axle or all axles exceeds the threshold value.
  • a risk of tipping is recognized if the lateral force of an inside wheel falls below a lower threshold value, while the lateral force of the outside wheel exceeds a high threshold value or if the lateral force of the outside wheel exceeds a high threshold value.
  • the conditions that the lateral force of a wheel on the inside of the curve falls below a lower threshold value, while the lateral force of the wheel on the outside of the curve exceeds a high threshold value or that the lateral force of the wheel on the outside of the curve exceeds a high threshold value can be considered selectively or over a longer period, with a risk of tipping over is then considered recognized if the conditions are fulfilled over a longer period of time or selectively. According to one embodiment, these conditions only have to be fulfilled on one or both axes, either selectively or over a longer period of time.
  • a risk of tipping is then recognized when the lateral force of an inside wheel first exceeds a maximum and then decreases, while the lateral force of the outside wheel continues to increase.
  • a risk of tipping is recognized if the lateral force of a wheel on the inside of the curve initially exceeds a maximum and then decreases, while the lateral force of the wheel on the outside of the curve continues to increase.
  • An advantageous device for determining vehicle condition variables in which at least one variable indicative of the vehicle tipping tendency about the vehicle longitudinal axis is measured and evaluated in an evaluation unit for determining control or control variables for a motor vehicle control system, has tire or wheel force sensors which Detect variables that represent the tire or wheel side forces and / or the tire or wheel contact forces, and in which the evaluation unit determines at least one characteristic variable (s) from the continuously recorded measurement variables on at least one vehicle wheel inside and outside the curve, the determined direct tires - or wheel forces themselves or signals derived therefrom and / or formed with the inclusion of correction variables or values, such as filtered variables, are fed to the control system as control variables.
  • the tilting states are preferably determined by monitoring the rare force information on the inside and outside of the vehicle wheels, preferably using the direct tire or wheel forces themselves or signals derived therefrom, such as filtered variables.
  • a determination unit which determines at least one associated tipping prevention threshold value for the at least one characteristic variable, the dependence on further measurement variables which were determined with conventional sensors, such as wheel speed sensors, and / or which reflect the current driving situation ( Cornering, straight ahead, coefficient of friction) is formed, and that a comparison unit is provided which compares the parameter with the tipping prevention threshold value, and which the comparator provides to the vehicle control system as a control or control variable.
  • a comparison unit is provided which compares the parameter with the tipping prevention threshold value, and which the comparator provides to the vehicle control system as a control or control variable.
  • a risk of tipping is recognized when the difference in lateral forces between the inside and outside wheel exceeds a threshold value that is a function of the lateral force, the longitudinal force and the vehicle speed.
  • a risk of tipping is recognized when the difference in lateral forces between the outer and inner wheels exceeds a threshold value which is a function of the lateral forces and their time derivatives, the longitudinal forces and the vehicle speed. Furthermore, a risk of tipping is considered to be recognized if one of the threshold values is exceeded over a defined period of time, that is to say the rare force differences of various control cycles that follow one another or are closely spaced in time. According to a further exemplary embodiment, a risk of tipping is considered to be recognized if the difference in the lateral forces between the inside and outside wheel of any axis or both axles exceeds the at least one tipping prevention threshold value selectively or over a longer period of time.
  • a risk of tipping is also recognized if the time gradient of the difference between the lateral force of the inside and outside wheel of an axle or all axles exceeds the tipping prevention threshold. Furthermore, a risk of tipping is considered to be recognized if the time gradient of the difference between the lateral force of the outer and inner wheel of an axle or all axles
  • Tilt prevention threshold exceeded selectively or over a longer period.
  • the device determines a risk of tipping if the lateral force of an inside wheel falls below a lower tipping prevention threshold, while the lateral force of the outside wheel exceeds a high tipping prevention threshold.
  • a risk of tipping is also recognized if the lateral force of the wheel on the outside of the curve exceeds a high threshold value.
  • the conditions that the lateral force of an inside wheel falls below a lower tilt prevention threshold, while the lateral force of the outside wheel exceeds a high tilt prevention threshold or that the lateral force of the outside wheel exceeds a high threshold, selectively or over a longer period of time must be fulfilled on one or both vehicle axles.
  • a risk of tipping is preferably recognized when the lateral force of an inside wheel first exceeds a maximum and then decreases, while the lateral force of the outside wheel continues to increase. According to an exemplary embodiment, this condition must be met on both axes.
  • the force information is preferably determined with the aid of tire sidewall torsion sensors.
  • Fig. 1 shows the distribution of forces on a vehicle axle when cornering a motor vehicle
  • Fig. 3 is a block diagram of a device
  • the evaluation unit 11 at least one parameter (s) is determined from the continuously recorded measured variables (tire or wheel forces) on at least one vehicle wheel inside and outside the curve, the direct tire or wheel forces determined themselves or variables derived therefrom, such as filtered variables and / or signals formed with the inclusion of correction variables or values are fed to the control system 12 as control variables.
  • a determination unit 15 at least one, for the at least one characteristic, associated tilt prevention threshold value is determined, which is a function of further measured variables, which were determined with sensors, such as wheel speed sensors, and / or which reflect the current driving situation (cornering, driving straight ahead, coefficient of friction ), educated.
  • a comparison unit 16 compares the parameter with the tilt prevention threshold value and makes the comparison result available to the motor vehicle control system 12 as a control or regulating variable.
  • the comparison unit 16 sums the determined tire or wheel forces, in particular lateral forces, on the at least one vehicle wheel inside and outside the curve of any vehicle axle or all vehicle axles and determines the characteristic variable (s) from the difference in the lateral forces.
  • the comparison unit 16 compares at least one of the tilt prevention threshold values with the characteristic variable or the time gradient of the characteristic variable selectively or over a defined period of time, preferably from the difference in the lateral forces between the inside and outside wheel in successive or closely spaced control cycles.
  • the evaluation unit 11 gives one for the function of the comparison result, such as when the tilt prevention threshold value is exceeded
  • Vehicle tilt tendency indicative control or rule size for the motor vehicle control system is
  • the size indicative of the vehicle tipping tendency is determined as follows:
  • the lateral forces of the wheels are essentially used. If the lateral force of a wheel on the inside of a curve falls below a low threshold value, while the side force of the wheel on the outside of the curve exceeds a high threshold value, this is a clear indication of a greatly reduced value Riot force on the inner wheel, so that a risk of tipping can be considered as given.
  • the part of the centrifugal force to be compensated by the wheels of the axle is identical to the sum of the lateral forces:
  • THR f (F lJ , F ⁇ fi , F, J , F xl , v) (5;
  • the force information can be the direct tire or wheel forces or further processed signals, such as force signals filtered with different time constants.
  • An improvement of the method consists in carrying out the threshold value not only depending on the lateral forces themselves but also on the gradients of the lateral forces:
  • a further improvement in the monitoring of the tipping behavior can be achieved in that an intervention is not only initiated selectively via a hard threshold crossing, but that the force relations are observed over a certain period of time in accordance with equations (4) to (9) and thus a time chain of determined force values is evaluated:
  • a risk of tipping is recognized if the values ⁇ F r [z] meet the conditions from equations (4) or (8) or (9) over a defined period of time.
  • threshold value THR can again be formed according to equation (5) or (7).
  • a further criterion for recognizing the risk of tipping is that the lateral force on the inside of the curve falls short of a small threshold value while the lateral force on the outside of the curve exceeds a high threshold value or the sole exceeding of a high threshold value by the lateral force on the outside of the curve:
  • Another very safe method to detect dangerous lifting of the wheels on the inside of the curve is to observe a characteristic course of the lateral forces of an axle over time. This course is shown in principle in FIG. 2. Initially, both lateral forces on an axle increase due to increasing transverse dynamics. The lateral force on the inside of the curve reaches a maximum at a certain lateral acceleration and then decreases continuously, while the lateral force on the outside of the curve continues to increase.
  • the lateral force on the outside wheel is opposite:
  • a method or a device for checking the typical characteristic of the two lateral forces of an axis according to the above equation and FIG. 2 is proposed for recognizing the situation.
  • the lateral force maximum on the inner wheel is exceeded, the lateral force of the inner wheel then decreases and the lateral force of the outer wheel increases further, a risk of tipping is recognized.

Abstract

L'invention concerne un procédé et un dispositif pour déterminer des grandeurs d'état de véhicule. Ce procédé consiste à mesurer au moins une grandeur, indiquant une tendance du véhicule à basculer autour de son axe longitudinal, et à évaluer cette grandeur pour déterminer des grandeurs de commande et de régulation d'un système de régulation de véhicule. L'invention vise à permettre une réaction la plus rapide possible à un risque de basculement du véhicule, au moyen d'une intervention de régulation. A cet effet, le procédé selon l'invention consiste, sur la base de la grandeur de mesure, qui est déterminée au moyen de détecteurs de forces exercées sur les pneus ou sur les roues et qui reproduit les forces latérales exercées sur les pneus ou sur les roues et/ou les forces de contact des pneus ou des roues, à déterminer au moins une grandeur caractéristique, indiquant une tendance du véhicule à basculer, par détermination continue de cette grandeur de mesure sur au moins une roue se trouvant à l'intérieur du virage et sur au moins une roue se trouvant à l'extérieur du virage. Les forces directes, exercées sur les pneus ou sur les roues, qui ont été déterminées, ou les grandeurs déduites de ces forces, par exemple des grandeurs filtrées, et/ou les signaux formés au moyen de grandeurs ou de valeurs de correction, sont utilisés en tant que grandeurs de commande ou de régulation.
EP00956417A 1999-08-13 2000-08-10 Procede et dispositif pour determiner des grandeurs d'etat de vehicule Withdrawn EP1311416A1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE19937856 1999-08-13
DE19937856 1999-08-13
DE10039108A DE10039108B4 (de) 1999-08-13 2000-08-07 Verfahren und Vorrichtung zum Bestimmen von Fahrzeugzustandsgrößen
DE10039108 2000-08-07
PCT/EP2000/007772 WO2001012483A1 (fr) 1999-08-13 2000-08-10 Procede et dispositif pour determiner des grandeurs d'etat de vehicule

Publications (1)

Publication Number Publication Date
EP1311416A1 true EP1311416A1 (fr) 2003-05-21

Family

ID=26006659

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00956417A Withdrawn EP1311416A1 (fr) 1999-08-13 2000-08-10 Procede et dispositif pour determiner des grandeurs d'etat de vehicule

Country Status (2)

Country Link
EP (1) EP1311416A1 (fr)
WO (1) WO2001012483A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10160059A1 (de) * 2000-12-30 2002-08-01 Bosch Gmbh Robert System und Verfahren zur Beurteilung eines Beladungszustandes eines Kraftfahrzeugs
US7831354B2 (en) 2004-03-23 2010-11-09 Continental Teves, Inc. Body state estimation of a vehicle
US7369927B2 (en) 2004-04-02 2008-05-06 Continental Teves, Inc. Active rollover protection utilizing steering angle rate map
US7239952B2 (en) 2004-12-08 2007-07-03 Continental Teves, Inc. Reduced order parameter identification for vehicle rollover control system
US7557697B2 (en) 2005-02-22 2009-07-07 Continental Teves, Inc. System to measure wheel liftoff
DE102019206875B3 (de) * 2019-05-13 2020-07-23 Volkswagen Aktiengesellschaft Erkennen einer Bankettfahrt eines Kraftfahrzeugs

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4416991A1 (de) * 1994-05-13 1995-11-16 Pietzsch Ag Verfahren und Einrichtung zum Warnen der Fahrer von Lastkraftwagen vor Kippgefahr bei Kurvenfahrten
DE4435160A1 (de) * 1994-09-30 1996-04-04 Continental Ag Einrichtung zur Ermittlung der Umfangskraft eines Fahrzeugrades
DE19529539A1 (de) 1995-08-11 1997-02-13 Man Nutzfahrzeuge Ag Verfahren zur ON-BOARD-Ermittlung von fahrdynamischen Sicherheitsreserven von Nutzfahrzeugen
DE19632943C2 (de) 1996-08-16 1999-10-21 Daimler Chrysler Ag Verfahren zum Betrieb eines Kraftfahrzeugs mit fahrstabilisierenden Bremseingriffen
DE19751891A1 (de) * 1997-11-22 1999-05-27 Bosch Gmbh Robert Verfahren und Vorrichtung zur Stabilisierung eines Fahrzeuges bei Kipptendenz
US6424907B1 (en) 1998-07-17 2002-07-23 Continental Teves Ag & Co., Ohg Method and device for determining and detecting the overturning hazard of a vehicle

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0112483A1 *

Also Published As

Publication number Publication date
WO2001012483A1 (fr) 2001-02-22
WO2001012483A8 (fr) 2001-10-04

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