WO2020178188A1 - Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle - Google Patents

Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle Download PDF

Info

Publication number
WO2020178188A1
WO2020178188A1 PCT/EP2020/055324 EP2020055324W WO2020178188A1 WO 2020178188 A1 WO2020178188 A1 WO 2020178188A1 EP 2020055324 W EP2020055324 W EP 2020055324W WO 2020178188 A1 WO2020178188 A1 WO 2020178188A1
Authority
WO
WIPO (PCT)
Prior art keywords
tire characteristic
tire
evaluation
control unit
characteristic curve
Prior art date
Application number
PCT/EP2020/055324
Other languages
German (de)
French (fr)
Inventor
Mehrdad Salari
Ulrich Mair
Julian KING
Original Assignee
Zf Friedrichshafen Ag
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
Application filed by Zf Friedrichshafen Ag filed Critical Zf Friedrichshafen Ag
Publication of WO2020178188A1 publication Critical patent/WO2020178188A1/en

Links

Classifications

    • 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
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/12—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to parameters of the vehicle itself, e.g. tyre models
    • 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
    • B60T8/172—Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters
    • 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
    • B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18—Propelling the vehicle
    • B60W30/18172—Preventing, or responsive to skidding of wheels
    • 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
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/02—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to ambient conditions
    • B60W40/06—Road conditions
    • B60W40/064—Degree of grip
    • 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
    • B60T2210/00—Detection or estimation of road or environment conditions; Detection or estimation of road shapes
    • B60T2210/10—Detection or estimation of road conditions
    • B60T2210/12—Friction
    • 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
    • B60T2270/00—Further aspects of brake control systems not otherwise provided for
    • B60T2270/86—Optimizing braking by using ESP vehicle or tire model
    • 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
    • B60W50/00—Details of control systems for road vehicle drive control not related to the control of a particular sub-unit, e.g. process diagnostic or vehicle driver interfaces
    • B60W2050/0001—Details of the control system
    • B60W2050/0019—Control system elements or transfer functions
    • B60W2050/0026—Lookup tables or parameter maps
    • 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
    • B60W50/00—Details of control systems for road vehicle drive control not related to the control of a particular sub-unit, e.g. process diagnostic or vehicle driver interfaces
    • B60W2050/0001—Details of the control system
    • B60W2050/0019—Control system elements or transfer functions
    • B60W2050/0028—Mathematical models, e.g. for simulation
    • B60W2050/0037—Mathematical models of vehicle sub-units
    • 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
    • B60W50/00—Details of control systems for road vehicle drive control not related to the control of a particular sub-unit, e.g. process diagnostic or vehicle driver interfaces
    • B60W2050/0062—Adapting control system settings
    • B60W2050/0075—Automatic parameter input, automatic initialising or calibrating means
    • B60W2050/0083—Setting, resetting, calibration
    • B60W2050/0088—Adaptive recalibration
    • 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
    • B60W2520/00—Input parameters relating to overall vehicle dynamics
    • B60W2520/26—Wheel slip
    • 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
    • B60W2520/00—Input parameters relating to overall vehicle dynamics
    • B60W2520/28—Wheel speed
    • 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
    • B60W2552/00—Input parameters relating to infrastructure
    • B60W2552/40—Coefficient of friction
    • 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
    • B60W2555/00—Input parameters relating to exterior conditions, not covered by groups B60W2552/00, B60W2554/00
    • B60W2555/20—Ambient conditions, e.g. wind or rain

Definitions

  • the present invention relates to a method and a system for determining at least one tire characteristic curve for at least one tire of a motor vehicle. Furthermore, the invention relates to a computer program product.
  • driving-dependent status data of the motor vehicle as well as status data of the roadway on which it is traveling, in particular the surface texture, are to be recorded and corresponding measured variables characterizing the status data are to be determined.
  • a speed of the motor vehicle can be determined by means of a speed sensor on at least one of the wheels.
  • the outside temperature can be determined or the condition of a road surface, for example an icy or damp road surface, can be detected. It can also be detected whether there is a slip, that is to say a difference between the rotational speed of the wheel and the speed of movement of the motor vehicle.
  • DE 10 2016 214 065 A1 discloses a method for determining a frictional limit between a tire and a surface on which the tire rolls in the longitudinal direction of the tire.
  • a momentary slip of the tire is initially recorded.
  • a momentary adhesion coefficient is then determined and a so-called tuple is formed from the detected slip and the current adhesion coefficient.
  • the maximum frictional connection limit is determined on the basis of the slope of a straight line through the origin through the tuple if the slip is below a first predetermined threshold value.
  • the maximum frictional connection limit is determined on the basis of a tangent gradient through the tuple if the slip is between the first and a second threshold value.
  • the maximum adhesion limit is determined directly on the basis of the adhesion coefficient if the slip is above the second predetermined one
  • Threshold is. Based on the prior art, the present invention is based on the object of providing a method and a system for determining at least one tire characteristic, with the aid of which a driving operation of the motor vehicle can be better monitored and a control of the motor vehicle can be optimized. The object is achieved by the subject matter of claims 1 and 5. Further advantageous embodiments can be found in the dependent claims.
  • state data which in turn serve to characterize at least one roadway on which the respective tire is traveling, as well as a maximum adhesion coefficient are recorded by a vehicle sensor system
  • Evaluation and control unit is coupled for data transmission, taking into account the status data recorded, a corresponding base tire characteristic stored on the evaluation and control unit is selected, the base tire characteristic curve in the event of a discrepancy between the maximum adhesion coefficient and one in the Base tire characteristic listed maximum base traction coefficient modifi ed and is stored by the evaluation and control unit as a modified tire characteristic in order to optimize control of the motor vehicle.
  • Typical data on the driving state of the motor vehicle and the surroundings of the motor vehicle, in particular the roadway on which the tires of the motor vehicle travel, are recorded by means of the vehicle sensor system.
  • the acquired status data is to be understood as meaning that certain threshold values are stored on the evaluation and control unit in order to divide the status data into status ranges from which the basic tire characteristic curve is selected.
  • the status data preferably include a road surface condition, surface moisture and / or a roughness of the road surface.
  • the vehicle sensor system uses suitable measurement systems to record the data on the condition of the roadway that is relevant for determining a tire characteristic. This can be for example information about a degree of moisture or a degree of icing of the surface of the road. Further status data are also conceivable, on the basis of which a meaningful basic tire characteristic can be selected. Driving situations of the motor vehicle are particularly relevant in which a comparatively low friction or a comparatively high slip between the tires of the motor vehicle and the road is to be expected, for example on icy, snow-covered or very wet roads.
  • the status data include information from an anti-lock braking system (ABS) and / or a traction control system (ASR).
  • ABS anti-lock braking system
  • ASR also known as traction control
  • data can be extracted from which, in particular, maximum adhesion coefficients can be determined, which are used by the evaluation and control unit to compare and modify the basic tire characteristic. Corresponding maximum adhesion coefficients can advantageously be determined for each road condition.
  • Other driver assistance systems are also conceivable that provide meaningful data, in particular on the current maximum coefficient of adhesion.
  • a driven or braked tire always has a slip in relation to the road surface on which it rolls, which is higher or lower depending on the tangential forces to be transmitted.
  • the coefficient between the tangential force and the normal force is called the coefficient of adhesion or coefficient of friction. Its maximum, i.e. the maximum coefficient of adhesion, indicates the maximum force a tire can transmit with a given normal force.
  • the recorded status data are made available to the evaluation and control unit, which is connected to the vehicle sensor system and which receives the information, processes it and compares it with databases or basic tire characteristics stored on the evaluation and control unit.
  • the evaluation and control unit which is connected to the vehicle sensor system and which receives the information, processes it and compares it with databases or basic tire characteristics stored on the evaluation and control unit.
  • databases or basic tire characteristics stored on the evaluation and control unit are on the Evaluation and control unit for each previously defined road condition, one or more basic tire characteristics are stored in advance. These can be supplied by the respective tire manufacturer or based on empirical data previously determined through tests.
  • the evaluation and control unit decides on the basis of the status data, in particular the condition of the roadway, which basic tire characteristic curve is used for a comparison with the real status data.
  • This basic tire characteristic curve has a maximum basic adhesion coefficient that is compared with the maximum adhesion coefficient that is obtained, for example, from the data of the anti-lock braking system and / or the traction control system. If the maximum basic adhesion coefficient and the recorded, ie current maximum adhesion coefficient, are identical, the basic tire characteristic curve is not modified. However, if the adhesion coefficients differ, the maximum adhesion coefficient and, based on this, the tire characteristic curve is modified by means of functions or arithmetic models stored on the evaluation and control unit.
  • a modified tire characteristic curve and a modified maximum adhesion coefficient are then available on the evaluation and control unit.
  • the course of the tire characteristic is generated on the basis of the recorded or modified maximum adhesion coefficient in combination with the function or arithmetic models already stored on the evaluation and control unit.
  • a modified tire characteristic curve with a modified maximum adhesion coefficient is generated and stored on the evaluation and control unit, it can replace the basic tire characteristic curve or also be saved as a further data record.
  • this (first) modified tire characteristic curve with the (first) modified maximum adhesion coefficient is used in the event of a recurring roadway condition and compared with a new recorded maximum adhesion coefficient, whereby, analogously to the manner described, none with an identical maximum adhesion coefficient Modification of the first modified tire characteristic takes place.
  • the adhesion coefficients differ, the first modified maximum adhesion coefficient and the first modified tire characteristic curve are modified from the evaluation and control unit is stored as a second modified tire characteristic.
  • the modified tire characteristic curve is preferably determined continuously or at defined time intervals.
  • a determination can take place when a road condition changes, for example when it rains or the road suddenly becomes icy.
  • a system for determining at least one tire characteristic curve for at least one tire of a motor vehicle comprises a vehicle sensor system which is designed to acquire status data, which in turn serve to characterize at least one roadway on which the respective tire is traveling, as well as a maximum adhesion coefficient, the vehicle sensor system having a Evaluation and control unit is coupled for data transmission, with a corresponding base tire characteristic stored on the evaluation and control unit being selectable, taking into account the recorded status data, the base tire characteristic curve in the event of a discrepancy between the maximum adhesion coefficient and one in the base tire characteristic curve listed maximum basic adhesion coefficient modifi ed and can be saved by the evaluation and control unit as a modified tire characteristic in order to optimize control of the motor vehicle. It is therefore a continuously learning system which checks the tire characteristics of the at least one tire in the case of recurring road conditions or other status data or status data changes and, if necessary, modifies them so that monitoring, prediction and control of the motor vehicle is optimized.
  • the vehicle sensor system can be arranged, for example, in the front area of the motor vehicle, in particular in the area of the front wheels, but also on the rear wheels of the motor vehicle, in order to be able to determine the status data required to select the corresponding basic tire characteristic. Furthermore can the system can be designed in such a way that a respective tire characteristic curve is determined for several or all tires of the motor vehicle in order to make monitoring and control of the motor vehicle even more precise.
  • the vehicle sensor system preferably comprises a camera system, a radar system and / or a lidar system.
  • Camera systems capture the road surface optically, with radar systems including detection and location methods and devices based on electromagnetic waves.
  • lidar systems enable optical distance or speed measurement by means of laser beams. With such systems it is possible to precisely and reliably record roadway conditions or further status data that are required for the determination or selection of the basic tire characteristic curve or an already modified tire characteristic curve.
  • the vehicle sensor system preferably comprises at least one wheel speed sensor.
  • the wheel speed sensor can be arranged, for example, in the aforementioned anti-lock braking system or in the traction control system. Using the at least one wheel speed sensor, it is possible to detect slip of the respective tire and to draw conclusions about the current maximum coefficient of adhesion.
  • the method according to the invention can in particular be carried out by a computer or by the evaluation and control unit.
  • the method can thus be implemented in software.
  • the corresponding software is an independently salable product. Therefore, the invention also relates to a computer program product with machine-readable instructions that, when they are executed on a computer or on an evaluation and control unit, the computer and / or the evaluation and control unit to a control logic of the system for determining at least upgrade a tire characteristic curve or cause a method according to the invention to be carried out.
  • a preferred embodiment of the invention is explained in more detail below with reference to the figures, the same or similar elements being provided with the same reference numerals.
  • FIG. 1 shows a greatly simplified schematic view of a motor vehicle with a system for determining tire characteristics for a tire of the motor vehicle
  • Fig. 2 is a graph with several tire characteristics between one
  • FIG. 3 shows a curve diagram with the tire characteristics according to FIG. 2 and a modified tire characteristic.
  • a motor vehicle 1 has two vehicle axles, namely a front and a rear axle 9, 10, wherein on the front and rear axles 9, 10 two wheels 6 each with a respective tire 2 arranged on a wheel rim 11 fastened are.
  • two wheels 6 each with a respective tire 2 arranged on a wheel rim 11 fastened are.
  • only one wheel 6 of the front axle 9 and one wheel 6 of the rear axle 10 are shown for perspective reasons.
  • the respective non-visible wheels are designed analogously.
  • the motor vehicle 1 has a system according to the invention for determining at least one tire characteristic curve for each tire 2, which includes a vehicle sensor system 3, which is designed to acquire status data that are used to characterize at least one roadway 4 traveled by the respective tire 2, as well as a maximum coefficient of adhesion is.
  • the vehicle sensor system 3 comprises a camera 7 which is arranged in the front area of the motor vehicle 1 and which determines a roadway condition of a roadway 4 on which the vehicle 1 is traveling in the direction of travel in front of the respective tire 2.
  • the camera 7 is oriented perpendicular to the direction of travel or to the roadway 4.
  • the road condition is exemplarily divided into four different conditions, namely borrowed dry, wet, snowy and icy.
  • the camera 7 detects whether the roadway is dry or wet, or whether it is covered with a snow or ice surface. Further subdivisions of the road conditions are also conceivable.
  • the vehicle sensor system 3 comprises several wheel speed sensors 8, which are each arranged on the wheels 6 of the motor vehicle 1.
  • the wheel speed sensors 8 are presently integrated in an anti-lock braking system (not shown) of the motor vehicle 1, but can also be provided separately.
  • conclusions can be drawn about the slip of the wheels 6 of the motor vehicle 1 and thus about a current maximum adhesion coefficient.
  • An evaluation and control unit 5 which is coupled to the vehicle sensor system 3 for data transmission, is arranged in the motor vehicle 1.
  • the evaluation and control unit 5 receives precise information from the camera 7 about the current state of the roadway 4 and from the wheel speed sensors 8 further data for determining the current maximum coefficient of adhesion.
  • the evaluation and control unit 5 therefore uses the data from the wheel speed sensors 8 to calculate the instantaneous maximum coefficient of adhesion 18, which is shown in more detail in FIG. 3.
  • This information is referred to here as status data and includes, in particular, a road surface condition, surface moisture and / or a roughness of the roadway 4.
  • FIGS. 2 and 3 show a diagram with several basic tire characteristic curves 12, 13, 14, 15 between a slip plotted on the abscissa 16 and a coefficient of adhesion plotted on the ordinate 17.
  • the evaluation and control unit 5 initially selects one of four basic tire characteristics 12, 13, 14, 15 stored on the evaluation and control unit 5 based on the acquired status data, in particular based on the road surface.
  • the first tire characteristic curve 12 corresponds to a dry road condition and the second tire characteristic curve 13 corresponds to a nem wet road condition.
  • the third tire characteristic curve 14 corresponds to a snow-covered road condition and the fourth tire characteristic curve 15 corresponds to an icy road condition.
  • the evaluation and control unit 5 records that the motor vehicle 1 is driving on a snow-covered roadway 4, which is why the third basic tire characteristic curve 14 is selected.
  • the real maximum traction coefficient 18 therefore does not correspond to the coefficient 19 stored on the evaluation and control unit 5.
  • the control of the motor vehicle 1 is therefore not optimal. This is recognized by the evaluation and control unit 5, the third basic tire characteristic curve 14 being subsequently adapted or modified and stored as a modified tire characteristic curve 20 by the evaluation and control unit 5. With the aid of the modified tire characteristic curve 20, control, monitoring and prediction of the ferry operation of the motor vehicle 1 is optimized.
  • the evaluation and control unit 5 would no longer use the basic tire characteristic curve 14, but rather the modified tire characteristic curve 20 for a comparison between the modified maximum adhesion coefficient 18 and a newly determined - not shown here - maximum adhesion coefficient.
  • a modified tire characteristic curve is preferably determined continuously.

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Control Of Driving Devices And Active Controlling Of Vehicle (AREA)
  • Tires In General (AREA)

Abstract

The invention relates to a method for determining at least one tire characteristic curve for at least one tire (2) of a motor vehicle (1), wherein condition data, which are used to characterize at least one roadway (4) travelled on by the particular tire (2), and a maximum adhesion coefficient are detected by a vehicle sensor system (3), wherein the vehicle sensor system (3) is coupled to an evaluation and control unit (5) for data transmission, a corresponding base tire characteristic curve stored in the evaluation and control unit (5) being selected taking into account the detected condition data, wherein the base tire characteristic curve is modified in the event of a deviation between the maximum adhesion coefficient and a maximum base adhesion coefficient listed in the base tire characteristic curve, and is stored by the evaluation and control unit (5) as a modified tire characteristic curve in order to optimize control of the motor vehicle (1). The invention also relates to a system for determining the at least one tire characteristic curve. The invention particularly relates to a computer program product.

Description

Verfahren und System zur Ermittlung mindestens einer Reifenkennlinie für zumindest einen Reifen eines Kraftfahrzeugs Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle
Die vorliegende Erfindung betrifft ein Verfahren sowie ein System zur Ermittlung min destens einer Reifenkennlinie für zumindest einen Reifen eines Kraftfahrzeugs. Fer ner betrifft die Erfindung ein Computerprogrammprodukt. The present invention relates to a method and a system for determining at least one tire characteristic curve for at least one tire of a motor vehicle. Furthermore, the invention relates to a computer program product.
Um eine Vorhersage über den Fährbetrieb eines Kraftfahrzeugs treffen zu können oder eine Steuerung des Kraftfahrzeugs zu ermöglichen, sind fahrbetriebsabhängige Zustandsdaten des Kraftfahrzeugs sowie Zustandsdaten der davon befahrenen Fahrbahn, insbesondere der Oberflächenbeschaffenheit zu erfassen und entspre chende, die Zustandsdaten charakterisierende Messgrößen zu bestimmen. Bei spielsweise kann eine Geschwindigkeit des Kraftfahrzeugs mittels eines Dreh zahlsensors an zumindest einem der Räder bestimmt werden. Ferner kann die Au ßentemperatur festgestellt oder die Beschaffenheit einer Fahrbahnoberfläche, also beispielsweise eine vereiste oder feuchte Fahrbahn detektiert werden. Ferner kann erfasst werden, ob ein Schlupf, das heißt ein Unterschied zwischen der Rotationsge schwindigkeit des Rades und der Bewegungsgeschwindigkeit des Kraftfahrzeugs vorliegt. In order to be able to make a prediction about the ferry operation of a motor vehicle or to enable control of the motor vehicle, driving-dependent status data of the motor vehicle as well as status data of the roadway on which it is traveling, in particular the surface texture, are to be recorded and corresponding measured variables characterizing the status data are to be determined. For example, a speed of the motor vehicle can be determined by means of a speed sensor on at least one of the wheels. Furthermore, the outside temperature can be determined or the condition of a road surface, for example an icy or damp road surface, can be detected. It can also be detected whether there is a slip, that is to say a difference between the rotational speed of the wheel and the speed of movement of the motor vehicle.
Aus der DE 10 2016 214 065 A1 geht ein Verfahren zum Bestimmen einer Kraft schlussgrenze zwischen einem Reifen und einem Untergrund, auf dem der Reifen rollt, in Längsrichtung des Reifens hervor. Dabei wird zunächst ein momentaner Schlupf des Reifens erfasst. Nachfolgend wird ein momentaner Kraftschlussbeiwert bestimmt und ein sogenanntes Tupel aus dem erfassten Schlupf und dem momenta nen Kraftschlussbeiwert gebildet. Ferner wird die maximale Kraftschlussgrenze auf der Basis der Steigung einer Ursprungsgerade durch das Tupel bestimmt, falls der Schlupf unter einem ersten vorbestimmten Schwellenwert liegt. Alternativ wird die maximale Kraftschlussgrenze auf der Basis einer Tangentensteigung durch das Tupel bestimmt, falls der Schlupf zwischen dem ersten und einem zweiten Schwel lenwert liegt. Die maximale Kraftschlussgrenze wird direkt auf der Basis des Kraft- schlussbeiwerts bestimmt, falls der Schlupf über dem zweiten vorbestimmten DE 10 2016 214 065 A1 discloses a method for determining a frictional limit between a tire and a surface on which the tire rolls in the longitudinal direction of the tire. A momentary slip of the tire is initially recorded. A momentary adhesion coefficient is then determined and a so-called tuple is formed from the detected slip and the current adhesion coefficient. Furthermore, the maximum frictional connection limit is determined on the basis of the slope of a straight line through the origin through the tuple if the slip is below a first predetermined threshold value. Alternatively, the maximum frictional connection limit is determined on the basis of a tangent gradient through the tuple if the slip is between the first and a second threshold value. The maximum adhesion limit is determined directly on the basis of the adhesion coefficient if the slip is above the second predetermined one
Schwellenwert liegt. Der vorliegenden Erfindung liegt ausgehend vom Stand der Technik die Aufgabe zu Grunde, ein Verfahren und ein System zur Ermittlung mindestens einer Reifenkennli nie bereitzustellen, mit Hilfe dessen ein Fährbetrieb des Kraftfahrzeugs besser über wachbar und eine Steuerung des Kraftfahrzeugs optimierbar ist. Die Aufgabe wird gelöst durch den Gegenstand der Patentansprüche 1 und 5. Weitere vorteilhafte Ausführungsformen sind den abhängigen Ansprüchen zu entnehmen. Threshold is. Based on the prior art, the present invention is based on the object of providing a method and a system for determining at least one tire characteristic, with the aid of which a driving operation of the motor vehicle can be better monitored and a control of the motor vehicle can be optimized. The object is achieved by the subject matter of claims 1 and 5. Further advantageous embodiments can be found in the dependent claims.
Nach einem erfindungsgemäßen Verfahren zur Ermittlung mindestens einer Reifen kennlinie für zumindest einen Reifen eines Kraftfahrzeugs werden durch eine Fahr zeugsensorik Zustandsdaten, die ihrerseits zur Charakterisierung zumindest einer von dem jeweiligen Reifen befahrenen Fahrbahn dienen, sowie ein maximaler Kraft- schlussbeiwert erfasst, wobei die Fahrzeugsensorik mit einer Auswert- und Steuer einheit zur Datenübertragung gekoppelt wird, wobei unter Berücksichtigung der er fassten Zustandsdaten eine entsprechende auf der Auswert- und Steuereinheit hin terlegte Basis-Reifenkennlinie ausgewählt wird, wobei die Basis-Reifenkennlinie im Fall einer Abweichung zwischen dem maximalen Kraftschlussbeiwert und einem in der Basis-Reifenkennlinie aufgeführten maximalen Basis-Kraftschlussbeiwert modifi ziert und von der Auswert- und Steuereinheit als modifizierte Reifenkennlinie gespei chert wird, um eine Steuerung des Kraftfahrzeugs zu optimieren. Mittels der Fahr zeugsensorik werden typische Daten über den Fahrzustand des Kraftfahrzeugs und der Umgebung des Kraftfahrzeugs, insbesondere der von den Reifen des Kraftfahr zeugs befahrenen Fahrbahn erfasst. According to a method according to the invention for determining at least one tire characteristic curve for at least one tire of a motor vehicle, state data, which in turn serve to characterize at least one roadway on which the respective tire is traveling, as well as a maximum adhesion coefficient are recorded by a vehicle sensor system Evaluation and control unit is coupled for data transmission, taking into account the status data recorded, a corresponding base tire characteristic stored on the evaluation and control unit is selected, the base tire characteristic curve in the event of a discrepancy between the maximum adhesion coefficient and one in the Base tire characteristic listed maximum base traction coefficient modifi ed and is stored by the evaluation and control unit as a modified tire characteristic in order to optimize control of the motor vehicle. Typical data on the driving state of the motor vehicle and the surroundings of the motor vehicle, in particular the roadway on which the tires of the motor vehicle travel, are recorded by means of the vehicle sensor system.
Unter der Berücksichtigung der erfassten Zustandsdaten ist zu verstehen, dass auf der Auswert- und Steuereinheit bestimmte Schwellwerte hinterlegt sind, um die Zu standsdaten in Zustandsbereiche einzuteilen, aus denen die Basis-Reifenkennlinie ausgewählt wird. Taking into account the acquired status data is to be understood as meaning that certain threshold values are stored on the evaluation and control unit in order to divide the status data into status ranges from which the basic tire characteristic curve is selected.
Bevorzugt umfassen die Zustandsdaten eine Fahrbahnbeschaffenheit, eine Oberflä chenfeuchtigkeit und/oder eine Rauigkeit der Fahrbahn. Anders gesagt erfasst die Fahrzeugsensorik durch geeignete Messsysteme die Daten über den Fahrbahnzu stand, welche für die Ermittlung einer Reifenkennlinie relevant sind. Dies können bei- spielsweise Informationen über einen Feuchtegrad oder einen Vereisungsgrad der Oberfläche der Fahrbahn sein. Auch weitere Zustandsdaten sind denkbar, anhand derer eine sinnvolle Basis-Reifenkennlinie auswählbar ist. Insbesondere sind Fahrsi tuationen des Kraftfahrzeugs relevant, bei denen eine vergleichsweise niedrige Rei bung bzw. ein vergleichsweise hoher Schlupf zwischen den Reifen des Kraftfahr zeugs und der Fahrbahn zu erwarten ist, beispielweise bei vereisten, schneebedeck ten oder sehr nassen Fahrbahnen. The status data preferably include a road surface condition, surface moisture and / or a roughness of the road surface. In other words, the vehicle sensor system uses suitable measurement systems to record the data on the condition of the roadway that is relevant for determining a tire characteristic. This can be for example information about a degree of moisture or a degree of icing of the surface of the road. Further status data are also conceivable, on the basis of which a meaningful basic tire characteristic can be selected. Driving situations of the motor vehicle are particularly relevant in which a comparatively low friction or a comparatively high slip between the tires of the motor vehicle and the road is to be expected, for example on icy, snow-covered or very wet roads.
Alternativ oder ergänzend umfassen die Zustandsdaten Informationen aus einem Antiblockiersystem (ABS) und/oder einem System zur Traktionskontrolle (ASR). Ein Antiblockiersystem wirkt beim Bremsen des Kraftfahrzeugs einem möglichen Blockie ren der Räder durch Reduzierung des Bremsdrucks entgegen, wohingegen eine ASR, auch Antriebsschlupfregelung genannt, dafür sorgt, dass die Räder beim An fahren des Wagens nicht durchdrehen und das Fahrzeug bei Kurvenfahrten nicht seitlich ausbrechen kann. Aus den genannten Systemen können Daten extrahiert werden, aus denen insbesondere maximale Kraftschlussbeiwerte bestimmbar sind, welche von der Auswert- und Steuereinheit zum Vergleich und zur Modifizierung der Basis-Reifenkennlinie genutzt werden. Dabei können vorteilhafterweise für jeden Fahrbahnzustand entsprechende maximale Kraftschlussbeiwerte ermittelt werden. Auch weitere Fahrassistenz-Systeme sind denkbar, die aussagekräftige Daten, ins besondere zum aktuellen maximalen Kraftschlussbeiwert liefern. As an alternative or in addition, the status data include information from an anti-lock braking system (ABS) and / or a traction control system (ASR). An anti-lock braking system counteracts possible locking of the wheels when the vehicle is braked by reducing the brake pressure, whereas ASR, also known as traction control, ensures that the wheels do not spin when the car starts and the vehicle cannot break sideways when cornering. From the systems mentioned, data can be extracted from which, in particular, maximum adhesion coefficients can be determined, which are used by the evaluation and control unit to compare and modify the basic tire characteristic. Corresponding maximum adhesion coefficients can advantageously be determined for each road condition. Other driver assistance systems are also conceivable that provide meaningful data, in particular on the current maximum coefficient of adhesion.
Ein angetriebener oder gebremster Reifen hat gegenüber der Fahrbahnoberfläche, auf der er abrollt, immer einen Schlupf, der je nach den zu übertragenen Tangential kräften höher oder niedriger ist. Der Koeffizient zwischen der Tangentialkraft und der Normalkraft wird als Kraftschlussbeiwert oder Reibbeiwert bezeichnet. Sein Maxi mum, also der maximale Kraftschlussbeiwert, gibt an, welche Kraft ein Reifen bei gegebener Normalkraft maximal übertragen kann. A driven or braked tire always has a slip in relation to the road surface on which it rolls, which is higher or lower depending on the tangential forces to be transmitted. The coefficient between the tangential force and the normal force is called the coefficient of adhesion or coefficient of friction. Its maximum, i.e. the maximum coefficient of adhesion, indicates the maximum force a tire can transmit with a given normal force.
Die erfassten Zustandsdaten werden der mit der Fahrzeugsensorik steuerungstech nisch verbundenen Auswert- und Steuereinheit bereitgestellt, welche die Informatio nen empfängt, weiterverarbeitet und mit auf der Auswert- und Steuereinheit hinterleg ten Datenbanken bzw. Basis-Reifenkennlinien abgleicht. Anders gesagt sind auf der Auswert- und Steuereinheit für jeden vorher definierten Fahrbahnzustand vorab eine oder mehrere Basis-Reifenkennlinien hinterlegt. Diese können vom jeweiligen Rei fenhersteller geliefert werden oder auf vorher durch Versuche ermittelten empiri schen Daten basieren. The recorded status data are made available to the evaluation and control unit, which is connected to the vehicle sensor system and which receives the information, processes it and compares it with databases or basic tire characteristics stored on the evaluation and control unit. In other words, are on the Evaluation and control unit for each previously defined road condition, one or more basic tire characteristics are stored in advance. These can be supplied by the respective tire manufacturer or based on empirical data previously determined through tests.
Zunächst entscheidet die Auswert- und Steuereinheit anhand der Zustandsdaten, insbesondere des Fahrbahnzustandes, welche Basis-Reifenkennlinie für ein Abglei chen mit den realen Zustandsdaten herangezogen wird. Diese Basis-Reifenkennlinie weist einen maximalen Basis-Kraftschlussbeiwert auf, der dem maximalen Kraft- schlussbeiwert, der beispielsweise aus den Daten des Antiblockiersystems und/oder des Systems zur Traktionskontrolle gewonnen wird, gegenübergestellt wird. Sind der maximale Basis-Kraftschlussbeiwert und der erfasste, also aktuelle maximale Kraft- schlussbeiwert identisch, erfolgt keine Modifizierung der Basis-Reifenkennlinie. Un terscheiden sich die Kraftschlussbeiwerte jedoch, erfolgt mittels auf der Auswert- und Steuereinheit hinterlegten Funktionen oder Rechenmodellen eine Modifizierung des maximalen Kraftschlussbeiwertes und darauf aufbauend der Reifenkennlinie. Mithin liegen dann eine modifizierte Reifenkennlinie und ein modifizierter maximaler Kraft- schlussbeiwert auf der Auswert- und Steuereinheit vor. Der Verlauf der Reifenkennli nie wird ausgehend vom erfassten bzw. modifizierten maximalen Kraftschlussbeiwert in Kombination mit den bereits auf der Auswert- und Steuereinheit hinterlegten Funk tion oder Rechenmodellen erzeugt. First of all, the evaluation and control unit decides on the basis of the status data, in particular the condition of the roadway, which basic tire characteristic curve is used for a comparison with the real status data. This basic tire characteristic curve has a maximum basic adhesion coefficient that is compared with the maximum adhesion coefficient that is obtained, for example, from the data of the anti-lock braking system and / or the traction control system. If the maximum basic adhesion coefficient and the recorded, ie current maximum adhesion coefficient, are identical, the basic tire characteristic curve is not modified. However, if the adhesion coefficients differ, the maximum adhesion coefficient and, based on this, the tire characteristic curve is modified by means of functions or arithmetic models stored on the evaluation and control unit. A modified tire characteristic curve and a modified maximum adhesion coefficient are then available on the evaluation and control unit. The course of the tire characteristic is generated on the basis of the recorded or modified maximum adhesion coefficient in combination with the function or arithmetic models already stored on the evaluation and control unit.
Wird eine modifizierte Reifenkennlinie mit modifiziertem maximalem Kraftschlussbei wert erzeugt und auf der Auswert- und Steuereinheit hinterlegt, kann diese die Basis- Reifenkennlinie ersetzen oder zusätzlich als weiterer Datensatz abgespeichert wer den. Im weiteren Betrieb des Kraftfahrzeugs wird dann bei einem wiederkehrenden Fahrbahnzustand diese (erste) modifizierte Reifenkennlinie mit dem (ersten) modifi zierten maximalen Kraftschlussbeiwert herangezogen und mit einem neuen erfassten maximalen Kraftschlussbeiwert abgeglichen, wobei analog zu der beschriebenen Art und Weise bei einem identischen maximalen Kraftschlussbeiwert keine Modifizierung der ersten modifizierten Reifenkennlinie erfolgt. Bei einem Abweichen der Kraft schlussbeiwerte erfolgt hingegen eine Modifizierung des ersten modifizierten maxi malen Kraftschlussbeiwertes und der ersten modifizierten Reifenkennlinie, die von der Auswert- und Steuereinheit als zweite modifizierte Reifenkennlinie gespeichert wird. Dadurch ist es möglich beispielsweise für die Fahrbahnzustände trocken, nass, vereist, etc. eine stetige Anpassung der Reifenkennlinie zu realisieren, wodurch ins besondere ein bereits erfolgter Verschleiß der Reifen berücksichtigt werden kann. Mithin ist ein Fahrverhalten des Kraftfahrzeugs besser überwachbar. If a modified tire characteristic curve with a modified maximum adhesion coefficient is generated and stored on the evaluation and control unit, it can replace the basic tire characteristic curve or also be saved as a further data record. In the further operation of the motor vehicle, this (first) modified tire characteristic curve with the (first) modified maximum adhesion coefficient is used in the event of a recurring roadway condition and compared with a new recorded maximum adhesion coefficient, whereby, analogously to the manner described, none with an identical maximum adhesion coefficient Modification of the first modified tire characteristic takes place. In contrast, if the adhesion coefficients differ, the first modified maximum adhesion coefficient and the first modified tire characteristic curve are modified from the evaluation and control unit is stored as a second modified tire characteristic. As a result, it is possible, for example, for the road conditions dry, wet, icy, etc. to implement a constant adaptation of the tire characteristic curve, whereby in particular any wear and tear on the tires that has already occurred can be taken into account. The driving behavior of the motor vehicle can therefore be better monitored.
Vorzugsweise erfolgt eine Ermittlung der modifizierten Reifenkennlinie kontinuierlich oder in definierten Zeitabständen. Insbesondere kann eine Ermittlung bei einem Wechsel eines Fahrbahnzustandes erfolgen, beispielsweise bei eintretendem Regen oder plötzlich vereister Fahrbahn. The modified tire characteristic curve is preferably determined continuously or at defined time intervals. In particular, a determination can take place when a road condition changes, for example when it rains or the road suddenly becomes icy.
Ein erfindungsgemäßes System zur Ermittlung mindestens einer Reifenkennlinie für zumindest einen Reifen eines Kraftfahrzeugs umfasst eine Fahrzeugsensorik, die zur Erfassung von Zustandsdaten, die ihrerseits zur Charakterisierung zumindest einer von dem jeweiligen Reifen befahrenen Fahrbahn dienen, sowie eines maximalen Kraftschlussbeiwertes ausgebildet ist, wobei die Fahrzeugsensorik mit einer Auswert- und Steuereinheit zur Datenübertragung gekoppelt ist, wobei unter Berücksichtigung der erfassten Zustandsdaten eine entsprechende auf der Auswert- und Steuereinheit hinterlegte Basis-Reifenkennlinie auswählbar ist, wobei die Basis-Reifenkennlinie im Fall einer Abweichung zwischen dem maximalen Kraftschlussbeiwert und einem in der Basis-Reifenkennlinie aufgeführten maximalen Basis-Kraftschlussbeiwert modifi zierbar und von der Auswert- und Steuereinheit als modifizierte Reifenkennlinie spei cherbar ist, um eine Steuerung des Kraftfahrzeugs zu optimieren. Es handelt sich somit um ein stetig lernendes System, welches Reifenkennlinien des zumindest ei nen Reifens bei wiederkehrenden Fahrbahnzuständen oder sonstigen Zustandsda ten oder Zustandsdatenänderungen überprüft und, wenn erforderlich, modifiziert, so- dass eine Überwachung, Vorhersage und Steuerung des Kraftfahrzeugs optimiert wird. A system according to the invention for determining at least one tire characteristic curve for at least one tire of a motor vehicle comprises a vehicle sensor system which is designed to acquire status data, which in turn serve to characterize at least one roadway on which the respective tire is traveling, as well as a maximum adhesion coefficient, the vehicle sensor system having a Evaluation and control unit is coupled for data transmission, with a corresponding base tire characteristic stored on the evaluation and control unit being selectable, taking into account the recorded status data, the base tire characteristic curve in the event of a discrepancy between the maximum adhesion coefficient and one in the base tire characteristic curve listed maximum basic adhesion coefficient modifi ed and can be saved by the evaluation and control unit as a modified tire characteristic in order to optimize control of the motor vehicle. It is therefore a continuously learning system which checks the tire characteristics of the at least one tire in the case of recurring road conditions or other status data or status data changes and, if necessary, modifies them so that monitoring, prediction and control of the motor vehicle is optimized.
Die Fahrzeugsensorik kann beispielsweise im Frontbereich des Kraftfahrzeugs, ins besondere im Bereich der Fronträder, aber auch an den Hinterrädern des Kraftfahr zeugs angeordnet sein, um die zur Auswahl der entsprechenden Basis- Reifenkennlinie erforderlichen Zustandsdaten bestimmen zu können. Ferner kann das System derart ausgebildet sein, dass für mehrere oder alle Reifen des Kraftfahr zeugs eine jeweilige Reifenkennlinie bestimmt wird, um eine Überwachung und Steuerung des Kraftfahrzeugs noch genauer zu gestalten. The vehicle sensor system can be arranged, for example, in the front area of the motor vehicle, in particular in the area of the front wheels, but also on the rear wheels of the motor vehicle, in order to be able to determine the status data required to select the corresponding basic tire characteristic. Furthermore can the system can be designed in such a way that a respective tire characteristic curve is determined for several or all tires of the motor vehicle in order to make monitoring and control of the motor vehicle even more precise.
Vorzugsweise umfasst die Fahrzeugsensorik ein Kamerasystem, ein Radarsystem und/oder ein Lidar-System. Kamerasysteme erfassen die Fahrbahnoberfläche op tisch, wobei Radarsysteme Erkennungs- und Ortungsverfahren und -gerate auf der Basis elektromagnetischer Wellen umfassen. Demgegenüber ermöglichen Lidar- Systeme eine optische Abstands- oder Geschwindigkeitsmessung mittels Laserstrah len. Mit derartigen Systemen ist es möglich, Fahrbahnzustände oder weitere Zu standsdaten, die für die Bestimmung bzw. Auswahl der Basis-Reifenkennlinie oder einer bereits modifizierten Reifenkennlinie erforderlich sind, insbesondere genau und sicher zu erfassen. The vehicle sensor system preferably comprises a camera system, a radar system and / or a lidar system. Camera systems capture the road surface optically, with radar systems including detection and location methods and devices based on electromagnetic waves. In contrast, lidar systems enable optical distance or speed measurement by means of laser beams. With such systems it is possible to precisely and reliably record roadway conditions or further status data that are required for the determination or selection of the basic tire characteristic curve or an already modified tire characteristic curve.
Bevorzugt umfasst die Fahrzeugsensorik zumindest einen Raddrehzahlsensor. Der Raddrehzahlsensor kann beispielsweise in dem genannten Antiblockiersystem oder dem System zur Traktionskontrolle angeordnet sein. Über den zumindest einen Rad drehzahlsensor ist es möglich, einen Schlupf des jeweiligen Reifens zu detektieren und daraus Rückschlüsse über den momentanen maximalen Kraftschlussbeiwert zu erhalten. The vehicle sensor system preferably comprises at least one wheel speed sensor. The wheel speed sensor can be arranged, for example, in the aforementioned anti-lock braking system or in the traction control system. Using the at least one wheel speed sensor, it is possible to detect slip of the respective tire and to draw conclusions about the current maximum coefficient of adhesion.
Das Verfahren gemäß der Erfindung kann insbesondere von einem Computer bezie hungsweise von der Auswert- und Steuereinheit ausgeführt werden. Somit kann das Verfahren in Software implementiert sein. Die entsprechende Software ist insofern ein eigenständig verkaufsfähiges Produkt. Daher bezieht sich die Erfindung auch auf ein Computerprogrammprodukt mit maschinenlesbaren Anweisungen, die, wenn sie auf einem Computer beziehungsweise auf einer Auswert- und Steuereinheit ausge führt werden, den Computer und/oder die Auswert- und Steuereinheit zu einer Steue rungslogik des Systems zur Ermittlung mindestens einer Reifenkennlinie aufwerten beziehungsweise dazu veranlassen, ein Verfahren gemäß der Erfindung auszufüh ren. Im Folgenden wird ein bevorzugtes Ausführungsbeispiel der Erfindung anhand der Figuren näher erläutert, wobei gleiche oder ähnliche Elemente mit dem gleichen Be zugszeichen versehen sind. Hierbei zeigt The method according to the invention can in particular be carried out by a computer or by the evaluation and control unit. The method can thus be implemented in software. In this respect, the corresponding software is an independently salable product. Therefore, the invention also relates to a computer program product with machine-readable instructions that, when they are executed on a computer or on an evaluation and control unit, the computer and / or the evaluation and control unit to a control logic of the system for determining at least upgrade a tire characteristic curve or cause a method according to the invention to be carried out. A preferred embodiment of the invention is explained in more detail below with reference to the figures, the same or similar elements being provided with the same reference numerals. Here shows
Fig. 1 eine stark vereinfachte schematische Ansicht eines Kraftfahrzeugs mit einem System zur Ermittlung von Reifenkennlinien für einen Reifen des Kraftfahrzeugs, 1 shows a greatly simplified schematic view of a motor vehicle with a system for determining tire characteristics for a tire of the motor vehicle,
Fig. 2 ein Kurvendiagramm mit mehreren Reifenkennlinien zwischen einem Fig. 2 is a graph with several tire characteristics between one
Schlupf eines Reifens des Kraftfahrzeugs gemäß Figur 1 und seinem Kraftschlussbeiwert, und Slip of a tire of the motor vehicle according to FIG. 1 and its coefficient of adhesion, and
Fig. 3 ein Kurvendiagramm mit den Reifenkennlinien gemäß Figur 2 sowie einer modifizierten Reifenkennlinie. FIG. 3 shows a curve diagram with the tire characteristics according to FIG. 2 and a modified tire characteristic.
Gemäß Fig. 1 weist ein Kraftfahrzeug 1 zwei Fahrzeugachsen, nämlich eine Vorder- und eine Hinterachse 9, 10 auf, wobei an der Vorder- und Hinterachse 9, 10 jeweils zwei Räder 6 mit einem jeweiligen auf einer Radfelge 1 1 angeordneten Reifen 2 be festigt sind. Vorliegend sind aus perspektivischen Gründen lediglich ein Rad 6 der Vorderachse 9 und ein Rad 6 der Hinterachse 10 dargestellt. Die jeweiligen nicht sichtbaren Räder sind analog dazu ausgebildet. According to Fig. 1, a motor vehicle 1 has two vehicle axles, namely a front and a rear axle 9, 10, wherein on the front and rear axles 9, 10 two wheels 6 each with a respective tire 2 arranged on a wheel rim 11 fastened are. In the present case, only one wheel 6 of the front axle 9 and one wheel 6 of the rear axle 10 are shown for perspective reasons. The respective non-visible wheels are designed analogously.
Das Kraftfahrzeug 1 weist ein erfindungsgemäßes System zur Ermittlung mindestens einer Reifenkennlinie für jeden Reifen 2 auf, das eine Fahrzeugsensorik 3 umfasst, welche zur Erfassung von Zustandsdaten, die zur Charakterisierung zumindest einer von dem jeweiligen Reifen 2 befahrenen Fahrbahn 4 dienen, sowie eines maximalen Kraftschlussbeiwertes ausgebildet ist. The motor vehicle 1 has a system according to the invention for determining at least one tire characteristic curve for each tire 2, which includes a vehicle sensor system 3, which is designed to acquire status data that are used to characterize at least one roadway 4 traveled by the respective tire 2, as well as a maximum coefficient of adhesion is.
Die Fahrzeugsensorik 3 umfasst eine im Frontbereich des Kraftfahrzeugs 1 angeord nete Kamera 7, die einen Fahrbahnzustand einer in Fahrtrichtung des Kraftfahr zeugs 1 vor dem jeweiligen Reifen 2 befahrenen Fahrbahn 4 ermittelt. Die Kamera 7 ist senkrecht zur Fahrtrichtung bzw. zur Fahrbahn 4 ausgerichtet. Im Folgenden wird der Fahrbahnzustand exemplarisch in vier unterschiedliche Zustände unterteilt, näm- lieh trocken, nass, verschneit und vereist. Mit anderen Worten wird von der Kamera 7 erfasst, ob die Fahrbahn trocken oder nass ist, oder ob sie mit einer Schnee- oder Eisfläche bedeckt ist. Auch weitere Untergliederungen der Fahrbahnzustände sind denkbar. The vehicle sensor system 3 comprises a camera 7 which is arranged in the front area of the motor vehicle 1 and which determines a roadway condition of a roadway 4 on which the vehicle 1 is traveling in the direction of travel in front of the respective tire 2. The camera 7 is oriented perpendicular to the direction of travel or to the roadway 4. In the following, the road condition is exemplarily divided into four different conditions, namely borrowed dry, wet, snowy and icy. In other words, the camera 7 detects whether the roadway is dry or wet, or whether it is covered with a snow or ice surface. Further subdivisions of the road conditions are also conceivable.
Ferner umfasst die Fahrzeugsensorik 3 mehrere Raddrehzahlsensoren 8, die jeweils an den Rädern 6 des Kraftfahrzeugs 1 angeordnet sind. Die Raddrehzahlsensoren 8 sind vorliegend in einem - nicht gezeigten - Antiblockiersystem des Kraftfahrzeugs 1 integriert, können aber auch separat vorgesehen werden. Mittels der Raddreh zahlsensoren 8 können Rückschlüsse über den Schlupf der Räder 6 des Kraftfahr zeugs 1 und damit über einen aktuellen maximalen Kraftschlussbeiwert gewonnen werden. Furthermore, the vehicle sensor system 3 comprises several wheel speed sensors 8, which are each arranged on the wheels 6 of the motor vehicle 1. The wheel speed sensors 8 are presently integrated in an anti-lock braking system (not shown) of the motor vehicle 1, but can also be provided separately. By means of the wheel speed sensors 8, conclusions can be drawn about the slip of the wheels 6 of the motor vehicle 1 and thus about a current maximum adhesion coefficient.
Im Kraftfahrzeug 1 ist eine Auswert- und Steuereinheit 5 angeordnet, die zur Daten übertragung mit der Fahrzeugsensorik 3 gekoppelt ist. Die Auswert- und Steuerein heit 5 erhält von der Kamera 7 genaue Informationen über den momentanen Zustand der Fahrbahn 4 und von den Raddrehzahlsensoren 8 weitere Daten zur Ermittlung des momentanen maximalen Kraftschlussbeiwertes. Mithin berechnet die Auswert - und Steuereinheit 5 aus den Daten der Raddrehzahlsensoren 8 den momentanen maximalen Kraftschlussbeiwert 18, der in Fig. 3 näher gezeigt ist. Diese Informatio nen werden hier als Zustandsdaten bezeichnet und umfassen insbesondere eine Fahrbahnbeschaffenheit, eine Oberflächenfeuchtigkeit und/oder eine Rauigkeit der Fahrbahn 4. An evaluation and control unit 5, which is coupled to the vehicle sensor system 3 for data transmission, is arranged in the motor vehicle 1. The evaluation and control unit 5 receives precise information from the camera 7 about the current state of the roadway 4 and from the wheel speed sensors 8 further data for determining the current maximum coefficient of adhesion. The evaluation and control unit 5 therefore uses the data from the wheel speed sensors 8 to calculate the instantaneous maximum coefficient of adhesion 18, which is shown in more detail in FIG. 3. This information is referred to here as status data and includes, in particular, a road surface condition, surface moisture and / or a roughness of the roadway 4.
Fig. 2 und Fig. 3 zeigen ein Diagramm mit mehreren Basis-Reifenkennlinien 12, 13, 14, 15 zwischen einem auf der Abszisse 16 aufgetragenen Schlupf und einem auf der Ordinate 17 aufgetragenen Kraftschlussbeiwert. FIGS. 2 and 3 show a diagram with several basic tire characteristic curves 12, 13, 14, 15 between a slip plotted on the abscissa 16 and a coefficient of adhesion plotted on the ordinate 17.
In dem vorliegenden Beispiel wird von der Auswert- und Steuereinheit 5 anhand der erfassten Zustandsdaten, insbesondere anhand der Fahrbahnbeschaffenheit zu nächst eine von vier auf der Auswert- und Steuereinheit 5 hinterlegten Basis- Reifenkennlinien 12, 13, 14, 15 ausgewählt. Die erste Reifenkennlinie 12 entspricht einem trockenen Fahrbahnzustand und die zweite Reifenkennlinie 13 entspricht ei- nem nassen Fahrbahnzustand. Die dritte Reifenkennlinie 14 entspricht einem schneebedeckten Fahrbahnzustand und die vierte Reifenkennlinie 15 entspricht ei nem vereisten Fahrbahnzustand. Beispielhaft wird von der Auswert- und Steuerein heit 5 erfasst, dass das Kraftfahrzeug 1 eine schneebedeckte Fahrbahn 4 befährt, weshalb die dritte Basis-Reifenkennlinie 14 ausgewählt wird. In the present example, the evaluation and control unit 5 initially selects one of four basic tire characteristics 12, 13, 14, 15 stored on the evaluation and control unit 5 based on the acquired status data, in particular based on the road surface. The first tire characteristic curve 12 corresponds to a dry road condition and the second tire characteristic curve 13 corresponds to a nem wet road condition. The third tire characteristic curve 14 corresponds to a snow-covered road condition and the fourth tire characteristic curve 15 corresponds to an icy road condition. For example, the evaluation and control unit 5 records that the motor vehicle 1 is driving on a snow-covered roadway 4, which is why the third basic tire characteristic curve 14 is selected.
Nach Fig. 3 wird ein für den jeweiligen momentanen Fahrbahnzustand, nämlich die schneebedeckte Fahrbahn 4, ermittelte maximale Kraftschlussbeiwert 18 mit einem in der dritten Basis-Reifenkennlinie 14 aufgeführten maximalen Basis- Kraftschlussbeiwert 19, wobei der momentane maximale Kraftschlussbeiwert 18 klei ner ist, als der in der dritten Basis-Reifenkennlinie 14 hinterlegte maximale Basis- Kraftschlussbeiwert 19. Mithin entspricht der reale maximale Kraftschlussbeiwert 18 nicht dem auf der Auswert- und Steuereinheit 5 hinterlegten Beiwert 19. Die Steue rung des Kraftfahrzeugs 1 erfolgt somit nicht optimal. Dies wird von der Auswert- und Steuereinheit 5 erkannt, wobei nachfolgend die dritte Basis-Reifenkennlinie 14 ange passt bzw. modifiziert wird und als modifizierte Reifen kenn linie 20 von der Auswert- und Steuereinheit 5 abgespeichert wird. Mithilfe der modifizierten Reifenkennlinie 20 wird eine Steuerung, Überwachung und Vorhersage des Fährbetriebs des Kraftfahr zeugs 1 optimiert. According to Fig. 3, a maximum adhesion coefficient 18 determined for the respective current roadway condition, namely the snow-covered roadway 4, with a maximum basic adhesion coefficient 19 listed in the third base tire characteristic curve 14, the current maximum adhesion coefficient 18 being smaller than that Maximum basic traction coefficient 19 stored in the third basic tire characteristic curve 14. The real maximum traction coefficient 18 therefore does not correspond to the coefficient 19 stored on the evaluation and control unit 5. The control of the motor vehicle 1 is therefore not optimal. This is recognized by the evaluation and control unit 5, the third basic tire characteristic curve 14 being subsequently adapted or modified and stored as a modified tire characteristic curve 20 by the evaluation and control unit 5. With the aid of the modified tire characteristic curve 20, control, monitoring and prediction of the ferry operation of the motor vehicle 1 is optimized.
Für den Fall, dass in einem späteren Fährbetrieb mittels der Fahrzeugsensorik 3 er neut eine schneebedeckte Fahrbahn 4 detektiert wird, würde die Auswert- und Steu ereinheit 5 nicht mehr auf die Basis-Reifenkennlinie 14, sondern auf die modifizierte Reifenkennlinie 20 zurückgreifen, um eine Gegenüberstellung zwischen dem modifi zierten maximalen Kraftschlussbeiwert 18 und einem neu ermittelten - hier nicht ge zeigten - maximalen Kraftschlussbeiwert durchzuführen. Anders gesagt erfolgt eine stetige Anpassung und Modifizierung aller in der Auswert- und Steuereinheit 5 hinter legten Reifenkennlinien unter Berücksichtigung der jeweiligen Zustandsdaten sowie des Verschleißes der Reifen 2, sodass eine Steuerung des Kraftfahrzeugs 1 opti miert wird. Die Ermittlung einer modifizierten Reifenkennlinie erfolgt vorzugsweise kontinuierlich. Bezuqszeichen Kraftfahrzeug In the event that a snow-covered roadway 4 is detected again in a later ferry operation by means of the vehicle sensor system 3, the evaluation and control unit 5 would no longer use the basic tire characteristic curve 14, but rather the modified tire characteristic curve 20 for a comparison between the modified maximum adhesion coefficient 18 and a newly determined - not shown here - maximum adhesion coefficient. In other words, there is a constant adaptation and modification of all tire characteristics stored in the evaluation and control unit 5, taking into account the respective status data and the wear of the tires 2, so that control of the motor vehicle 1 is optimized. A modified tire characteristic curve is preferably determined continuously. Reference motor vehicle
Reifen tires
Fahrzeugsensorik Vehicle sensors
Fahrbahn roadway
Auswert- und Steuereinheit Evaluation and control unit
Rad wheel
Kamera camera
Raddrehzahlsensor Wheel speed sensor
Vorderachse Front axle
Hinterachse Rear axle
Radfelge Wheel rim
Erste Reifenkennlinie First tire curve
Zweite Reifenkennlinie Second tire characteristic
Dritte Reifenkennlinie Third tire characteristic
Vierte Reifenkennlinie Fourth tire characteristic
Abszisse abscissa
Ordinate ordinate
Ermittelter maximaler Kraftschlussbeiwert Maximaler Basis-Kraftschlussbeiwert Modifizierte Reifenkennlinie Determined maximum adhesion coefficient Maximum basic adhesion coefficient Modified tire characteristic

Claims

Patentansprüche Claims
1. Verfahren zur Ermittlung mindestens einer Reifenkennlinie für zumindest einen Reifen (2) eines Kraftfahrzeugs (1 ), wobei durch eine Fahrzeugsensorik (3) Zu standsdaten, die ihrerseits zur Charakterisierung zumindest einer von dem jeweiligen Reifen (2) befahrenen Fahrbahn (4) dienen, sowie ein maximaler Kraftschlussbeiwert erfasst werden, wobei die Fahrzeugsensorik (3) mit einer Auswert- und Steuerein heit (5) zur Datenübertragung gekoppelt wird, wobei unter Berücksichtigung der er fassten Zustandsdaten eine entsprechende auf der Auswert- und Steuereinheit (5) hinterlegte Basis-Reifenkennlinie ausgewählt wird, wobei die Basis-Reifenkennlinie im Fall einer Abweichung zwischen dem maximalen Kraftschlussbeiwert und einem in der Basis-Reifenkennlinie aufgeführten maximalen Basis-Kraftschlussbeiwert mo difiziert und von der Auswert- und Steuereinheit (5) als modifizierte Reifenkennlinie gespeichert wird, um eine Steuerung des Kraftfahrzeugs (1 ) zu optimieren. 1. A method for determining at least one tire characteristic curve for at least one tire (2) of a motor vehicle (1), with a vehicle sensor system (3) providing status data which in turn serves to characterize at least one roadway (4) on which the respective tire (2) is traveling , as well as a maximum adhesion coefficient can be recorded, the vehicle sensor system (3) being coupled to an evaluation and control unit (5) for data transmission, with a corresponding base stored on the evaluation and control unit (5) taking into account the status data. Tire characteristic is selected, the basic tire characteristic in the event of a discrepancy between the maximum adhesion coefficient and a maximum base adhesion coefficient listed in the basic tire characteristic modified and stored by the evaluation and control unit (5) as a modified tire characteristic in order to control to optimize the motor vehicle (1).
2. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass eine Ermittlung der modifizierten Reifenkennlinie kontinuierlich oder in definierten Zeitabständen erfolgt. 2. The method according to claim 1, characterized in that the modified tire characteristic curve is determined continuously or at defined time intervals.
3. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Zustandsdaten eine Fahrbahnbeschaffenheit, eine Oberflächenfeuchtigkeit und/oder eine Rauigkeit der Fahrbahn (4) umfassen. 3. The method according to any one of the preceding claims, characterized in that the status data include a road surface condition, surface moisture and / or a roughness of the roadway (4).
4. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Zustandsdaten Informationen aus einem Antiblockiersystem und/oder einem System zur Traktionskontrolle umfassen. 4. The method according to any one of the preceding claims, characterized in that the status data comprise information from an anti-lock braking system and / or a system for traction control.
5. System zur Ermittlung mindestens einer Reifenkennlinie für zumindest einen Rei fen (2) eines Kraftfahrzeugs (1 ), umfassend eine Fahrzeugsensorik (3), die zur Er fassung von Zustandsdaten, die ihrerseits zur Charakterisierung zumindest einer von dem jeweiligen Reifen (2) befahrenen Fahrbahn (4) dienen, sowie eines maximalen Kraftschlussbeiwertes ausgebildet ist, wobei die Fahrzeugsensorik (3) mit einer Aus wert- und Steuereinheit (5) zur Datenübertragung gekoppelt ist, wobei unter Berück sichtigung der erfassten Zustandsdaten eine entsprechende auf der Auswert- und Steuereinheit (5) hinterlegte Basis-Reifenkennlinie auswählbar ist, wobei die Basis- Reifenkennlinie im Fall einer Abweichung zwischen dem maximalen Kraftschlussbei- wert und einem in der Basis-Reifenkennlinie aufgeführten maximalen Basis- Kraftschlussbeiwert modifizierbar und von der Auswert- und Steuereinheit (5) als modifizierte Reifenkennlinie speicherbar ist, um eine Steuerung des Kraftfahr zeugs (1 ) zu optimieren. 5. A system for determining at least one tire characteristic curve for at least one tire (2) of a motor vehicle (1), comprising a vehicle sensor system (3) which is used to record status data which in turn characterizes at least one of the respective tires (2) traveled on Roadway (4) serve, and a maximum adhesion coefficient is formed, wherein the vehicle sensor system (3) is coupled to an evaluation and control unit (5) for data transmission, taking into account the recorded status data, a corresponding on the evaluation and Control unit (5) stored basic tire characteristic can be selected, the basic tire characteristic in the event of a discrepancy between the maximum adhesion coefficient and a maximum basic adhesion coefficient listed in the basic tire characteristic and can be modified by the evaluation and control unit (5) as modified tire characteristic can be stored in order to optimize control of the motor vehicle (1).
6. System nach Anspruch 5, dadurch gekennzeichnet, dass die Fahrzeugsensorik (3) ein Kamerasystem, ein Radarsystem und/oder ein Lidar-System umfasst. 6. System according to claim 5, characterized in that the vehicle sensor system (3) comprises a camera system, a radar system and / or a lidar system.
7. System nach einem der Ansprüche 5 oder 6, dadurch gekennzeichnet, dass die Fahrzeugsensorik (3) zumindest einen Raddrehzahlsensor (8) umfasst. 7. System according to one of claims 5 or 6, characterized in that the vehicle sensor system (3) comprises at least one wheel speed sensor (8).
8. Computerprogrammprodukt, enthaltend maschinenlesbare Anweisungen, die, wenn sie auf einem Computer, und/oder auf einer Auswert- und Steuereinheit (5) ausgeführt werden, den Computer, und/oder die Auswert- und Steuereinheit (5), zu einer Steuerungslogik des Systems zur Ermittlung mindestens einer Reifenkennlinie nach den Ansprüchen 5 bis 7 aufwerten, und/oder dazu veranlassen, ein Verfahren nach einem der Ansprüche 1 bis 4 auszuführen. 8. Computer program product containing machine-readable instructions which, when executed on a computer and / or on an evaluation and control unit (5), convert the computer and / or the evaluation and control unit (5) to a control logic of the Upgrade the system for determining at least one tire characteristic curve according to claims 5 to 7 and / or cause a method according to one of claims 1 to 4 to be carried out.
PCT/EP2020/055324 2019-03-01 2020-02-28 Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle WO2020178188A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019202803.9A DE102019202803A1 (en) 2019-03-01 2019-03-01 Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle
DE102019202803.9 2019-03-01

Publications (1)

Publication Number Publication Date
WO2020178188A1 true WO2020178188A1 (en) 2020-09-10

Family

ID=69723954

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2020/055324 WO2020178188A1 (en) 2019-03-01 2020-02-28 Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle

Country Status (2)

Country Link
DE (1) DE102019202803A1 (en)
WO (1) WO2020178188A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102020213513A1 (en) * 2020-10-28 2022-04-28 Zf Friedrichshafen Ag Method for determining and monitoring the tire condition of a tire of a vehicle
CN113449436B (en) * 2021-07-22 2022-03-25 中铁二院工程集团有限责任公司 Method for acquiring locomotive traction characteristic curve in complex operation environment
CN116443022B (en) * 2023-06-19 2023-08-15 成都赛力斯科技有限公司 Method and device for adjusting vehicle based on road surface tire adhesion coefficient

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19855332A1 (en) * 1998-12-01 2000-06-08 Daimler Chrysler Ag Method and device for determining the adhesion and adhesion limit in vehicle tires
DE10010306A1 (en) * 2000-03-06 2001-09-13 Porsche Ag Traction potential determination method for vehicles, involves calculating corrected friction coefficient based on correction factor of various vehicle parameters
EP2335046A1 (en) * 2008-09-19 2011-06-22 Aalto University Foundation Friction estimation method
DE102016214065A1 (en) 2016-07-29 2018-02-01 Zf Friedrichshafen Ag Determination of a maximum traction limit

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3705983A1 (en) * 1986-03-04 1987-09-10 Volkswagen Ag Device for monitoring the utilisation factor of the coefficient of road friction prevailing in the braking and/or acceleration of a motor vehicle
DE4010507C1 (en) * 1990-04-02 1991-10-17 Volkswagen Ag, 3180 Wolfsburg, De
DE102016203545A1 (en) * 2016-03-03 2017-09-07 Continental Teves Ag & Co. Ohg Method of determining road grip classes

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19855332A1 (en) * 1998-12-01 2000-06-08 Daimler Chrysler Ag Method and device for determining the adhesion and adhesion limit in vehicle tires
DE10010306A1 (en) * 2000-03-06 2001-09-13 Porsche Ag Traction potential determination method for vehicles, involves calculating corrected friction coefficient based on correction factor of various vehicle parameters
EP2335046A1 (en) * 2008-09-19 2011-06-22 Aalto University Foundation Friction estimation method
DE102016214065A1 (en) 2016-07-29 2018-02-01 Zf Friedrichshafen Ag Determination of a maximum traction limit

Also Published As

Publication number Publication date
DE102019202803A1 (en) 2020-09-03

Similar Documents

Publication Publication Date Title
DE3878674T2 (en) SYSTEM IN A MOTOR VEHICLE TO DETERMINE ROAD ADHAESION IN A DYNAMIC WAY.
WO2020178188A1 (en) Method and system for determining at least one tire characteristic curve for at least one tire of a motor vehicle
EP2355990B1 (en) Method for determining the roadway condition of a road section driven upon by a motor vehicle
DE102009041566A1 (en) Method for determination of road friction coefficient, involves updating constant frictional coefficient characteristic during drive, which is determined as constant
EP1572489B1 (en) Method for controlling a shiftable clutch in the drive train of a 4-wheel drive motor vehicle
DE19615311B4 (en) Method and device for controlling a movement quantity representing the vehicle movement
WO2013026503A1 (en) Method and control device for carrying out open-loop or closed-loop control of a vehicle brake system
EP1303433B1 (en) Method and device for stabilizing a road vehicle
EP1359076B1 (en) Method and apparatus for controlling the brake application energy of electronic controlled braking systems of combinations of at least one tractor and one trailer
DE19855332A1 (en) Method and device for determining the adhesion and adhesion limit in vehicle tires
DE102006033446B4 (en) Temperature-dependent trigger control for a traction control system
DE102006053827A1 (en) Method for detecting the loading of a motor vehicle
EP1480855A1 (en) Method and device for recognising raised wheels of a vehicle
EP2029404B1 (en) Antilock braking system, particularly for off-road vehicles
DE102005060023A1 (en) Method and device for determining a maximum coefficient of friction on a wheel of a stationary vehicle
WO2004080783A1 (en) Steering device for vehicles comprising a pair of wheels which can be freely steered by means of lateral forces
EP0976629A2 (en) Procedure and device for brake performance adaptation at momentary wheel - road -adhesion conditions
EP1070623B1 (en) Method for anti-skid control
EP1575790A1 (en) Method for indirectly identifying the loss of pressure on a motor vehicle wheel
WO2009089972A1 (en) Method for distributing the drive torque to the wheels of a vehicle as a function of the status of the wheel
DE102018005614B4 (en) Method for controlling a powertrain, control arrangement for controlling a powertrain, powertrain, vehicle, computer program and computer-readable medium
DE19602170A1 (en) Procedure for determining route conditions
DE102020200760A1 (en) Vehicle guidance method and electronic vehicle guidance system
DE102023200587B3 (en) Method for determining a current friction value of a brake
DE102012204671A1 (en) Method for determining frictional relationship between road surface and wheel of motor car, involves determining adhesion frictional relationship between wheel and road surface based on predetermined allocation function

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20707639

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 20707639

Country of ref document: EP

Kind code of ref document: A1