EP1948454A1 - Indirect tire pressure monitoring method - Google Patents

Indirect tire pressure monitoring method

Info

Publication number
EP1948454A1
EP1948454A1 EP06819461A EP06819461A EP1948454A1 EP 1948454 A1 EP1948454 A1 EP 1948454A1 EP 06819461 A EP06819461 A EP 06819461A EP 06819461 A EP06819461 A EP 06819461A EP 1948454 A1 EP1948454 A1 EP 1948454A1
Authority
EP
European Patent Office
Prior art keywords
temperature
tire
sub
pressure loss
compensation
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Withdrawn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
EP06819461A
Other languages
German (de)
French (fr)
Inventor
Markus Irth
Andreas Köbe
Christian Sussmann
Franko Blank
Vladimir Koukes
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 AG
Continental Teves AG and Co OHG
Original Assignee
Continental AG
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
Application filed by Continental AG, Continental Teves AG and Co OHG filed Critical Continental AG
Publication of EP1948454A1 publication Critical patent/EP1948454A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
    • B60C23/06—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle
    • B60C23/061—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle by monitoring wheel speed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
    • B60C23/06—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle
    • B60C23/061—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle by monitoring wheel speed
    • B60C23/062—Frequency spectrum analysis of wheel speed signals, e.g. using Fourier transformation

Definitions

  • the invention relates to a method according to the preamble of claim 1 and a computer program product.
  • Tire pressure monitoring systems protect vehicle occupants from vehicle damage due, for example, to abnormal tire air pressure.
  • an abnormal tire air pressure can increase tire wear and fuel consumption or lead to a tire defect ("tire burst")
  • Tire pressure monitoring systems are already known which operate either on the basis of directly measuring sensors or through evaluation of engine speed or torque Vibration characteristics of the vehicle wheels detect an abnormal tire pressure.
  • a so-called indirectly measuring tire pressure monitoring system (DDS: Deflation Detection System) is known, which detects a tire pressure loss by evaluating the wheel rotational movement.
  • DDS Deflation Detection System
  • a tire pressure determining apparatus is known which determines a pressure loss in a tire based on tire vibrations.
  • EP 0 895 880 A2 discloses an apparatus for estimating the air pressure of a tire comprising a temperature sensor which measures the outside air temperature. Based on the determined outside air temperature, effects of the temperature on the resonance frequency of the tire are corrected.
  • the object of the invention is to provide a tire pressure monitoring system for a motor vehicle based on the evaluation of the tire vibrations, in which the influence of the temperature is taken into account.
  • the invention is based on the idea of determining a compensation quantity for at least one pressure loss analysis quantity, which is obtained by analyzing the torsional natural vibration behavior of at least one tire.
  • this compensation quantity depends on a tire temperature calculated by means of a temperature model.
  • a quotient of change in the pressure loss analysis quantity to temperature change is used for the compensation quantity. This directly reflects the influence of temperature on the pressure loss analysis size. It is likewise preferred that a compensation variable is determined for each pressure loss analysis variable. Thus, an individual correction of any pressure loss analysis size is possible.
  • the pressure loss analysis variable is preferably a natural frequency or natural frequency shift determined during a natural frequency analysis.
  • the pressure loss analysis quantity is a quantity resulting from frequency shift and other spectrally describing quantities, or a spring constant describing the tire.
  • the temperature model used takes into account at least one of the following heat quantity changes to calculate the tire temperature:
  • the compensation variable (s) is / are taught in, the pressure loss analysis variable (s) being considered together with the calculated tire temperature (s) via one or more journeys for teaching the compensation variable (s). Learning over a longer period of time can provide sufficient statistical see the relevance of the result.
  • the tire temperature is determined by temporal integration of the at least one heat quantity change.
  • the tire temperature is determined by integration of all heat quantity changes.
  • outside temperature At least two of the following variables are preferably used: outside temperature
  • T En gine t brake temperature (T Br ake) t life of the vehicle, driving profile since switching on the ignition, in particular vehicle speed (v), yaw rate, lateral acceleration, drive torque and / or driven mileage, environment sensor information, in particular rain sensor and / or dew point sensor information.
  • An advantage of the method according to the invention is the reduced risk of false alarms or the risk of non-warning in the event of pressure loss.
  • the invention also relates to a computer program product which defines an algorithm according to the method described above.
  • Show it 1 is a schematic block diagram of a temperature compensation in a frequency analysis
  • FIG. 2 is a schematic block diagram of a tire temperature calculation.
  • the tire temperature has an influence on the pressure in the tire. From an increased tire temperature follows an increased tire pressure, thus increased tire stiffness and increased natural frequency. However, the stiffness of the tire material (rubber) is also affected by the temperature. An increased temperature results in a softer rubber, thus a lower stiffness and a lower natural frequency. It has been shown that the two effects do not compensate for their influence on the tire and thus preferably on the natural frequency, but that the effect is dependent on material, tire temperature and internal pressure. This leads to changes in the torsional vibration behavior of a tire when driving with high temperature fluctuations, which are in the wide range of changes in a pressure loss. This is associated with an increased risk of false alarms or non-alarms in case of pressure loss.
  • a pressure loss analysis size is determined for at least one tire, preferably for each tire.
  • the natural frequency shift f from the frequency analysis is used in the following description.
  • a pressure loss analysis variable which results from frequency shift and other spectrally describing variables, as described in greater detail in WO 2005/005174 A1, for example, or also with a spring constant of the tire, as for example in EP 0 895 880 A2 disclosed.
  • fvL / fvR / fm for each wheel there is a frequency shift fvL / fvR / fm, ff "(VR: front right, HR: right rear, VL: front left, HL: rear left).
  • Fig. 1 is a schematic block diagram of an exemplary method is shown, which solves the above-mentioned problem of Reifentemperatureinhnes.
  • the natural frequency f k (where the index k stands for VL, VR, HL or HR) of the tire is learned together with a calculated tire temperature T Rei f e n. From this ensemble a compensation quantity for the temperature influence is determined, which is applied to the determined natural frequencies f k .
  • an empirical mean value eg -0.5 Hz / 10 ° C.
  • a tire temperature T Rei n e is then calculated from various driving, driving condition, vehicle and environmental information X n , such as the outside temperature, service life, coolant temperature, driving speed, driving profile, etc. with the aid of a temperature model 1.
  • the natural frequencies of the wheels f VL , f VR , f HL , f HR are determined accordingly. If temperature / frequency values are present, a correction factor 2 is learned. This is used to get out of the Basic compensation 3 to determine a current temperature compensation value 4, with which the temperature-compensated natural frequencies f ' VL , f'vR / f% L, f' HR are determined.
  • the temperature model one used to calculate the tire temperature T Rei fen example according to the following information:
  • Outside temperature T outside available either via a temperature sensor in the control unit or via CAN messages, such as outside air temperature and intake air temperature,
  • Service life of the vehicle Estimation sometimes via the coolant temperature or engine temperature T Engine in combination with the outside temperature T Outside , if no service life is available,
  • Driving profile available from the speed signal v, yaw rate or lateral acceleration and drive torque.
  • calculated quantities such as e.g. Mileage since "Ignition-On", and
  • A radiating surface of the tire
  • CCs proportionality constant of radiant heat
  • ⁇ k constant of proportionality of convection
  • f proportionality constant of rolling resistance
  • T Rei fen tire temperature
  • the tire temperature T Tire can then be calculated by integrating the heat quantity changes according to:
  • FIG. 2 schematically illustrates an example method for calculating the tire temperature T tire according to the above equation. From outside temperature T outside , driving speed v, brake temperature T brake , engine temperature T engine and a starting value T st a r t for the tire temperature, the four heat

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Tires In General (AREA)
  • Measuring Fluid Pressure (AREA)

Abstract

The invention relates to an indirect tire pressure monitoring method during which an analysis of the natural oscillation behavior of at least one tire is carried out and at least one pressure drop analysis quantity (f<SUB>VL</SUB>, f<SUB>VR</SUB>, f<SUB>HL</SUB>, f<SUB>HR</SUB>), particularly a natural oscillation is determined. A temperature compensation (4) of the pressure drop analysis quantity (f<SUB>VL</SUB>, f<SUB>VR</SUB>, f<SUB>HL</SUB>, f<SUB>HR</SUB>) is carried out, and in order to determine a compensation quantity (2), particularly the quotient from changing the pressure drop analysis quantity and temperature change, a tire temperature (T<SUB>tire</SUB>) calculated by using a temperature model (1) is used.

Description

Verfahren zur indirekten ReifendrucküberwachungMethod for indirect tire pressure monitoring
Die Erfindung betrifft ein Verfahren gemäß Oberbegriff von Anspruch 1 sowie ein Computerprogrammprodukt.The invention relates to a method according to the preamble of claim 1 and a computer program product.
In modernen Kraftfahrzeugen finden vermehrt Systeme Anwendung, welche zu einem aktiven oder passiven Schutz der Insassen beitragen. Systeme zur Reifendrucküberwachung schützen die Fahrzeuginsassen vor Fahrzeugschäden, welche beispielsweise auf einen abnormalen Reifenluftdruck zurückzuführen sind. Durch einen abnormalen Reifenluftdruck können sich beispielsweise der Reifenverschleiß und der Kraftstoffverbrauch erhöhen oder es kann zu einem Reifendefekt („Rei- fenplatzer") kommen. Es sind bereits verschiedene Reifendrucküberwachungssysteme bekannt, welche entweder auf Basis direkt messender Sensoren arbeiten oder durch Auswertung von Drehzahl- oder Schwingungseigenschaften der Fahrzeugräder einen abnormalen Reifendruck erkennen.In modern motor vehicles systems are increasingly used, which contribute to an active or passive protection of the occupants. Tire pressure monitoring systems protect vehicle occupants from vehicle damage due, for example, to abnormal tire air pressure. For example, an abnormal tire air pressure can increase tire wear and fuel consumption or lead to a tire defect ("tire burst") Various tire pressure monitoring systems are already known which operate either on the basis of directly measuring sensors or through evaluation of engine speed or torque Vibration characteristics of the vehicle wheels detect an abnormal tire pressure.
Aus der DE 100 58 140 Al ist ein so genanntes indirekt messendes Reifendrucküberwachungssystem (DDS: Deflation Detec- tion System) bekannt, welches durch Auswertung der Raddrehbewegung einen Reifendruckverlust detektiert. 826 Bl ist ein Reifendruckbestimmungsvorrichtung bekannt, welcher auf Basis von Reifenschwingungen einen Druckverlust in einem Reifen ermittelt.From DE 100 58 140 Al a so-called indirectly measuring tire pressure monitoring system (DDS: Deflation Detection System) is known, which detects a tire pressure loss by evaluating the wheel rotational movement. 826 Bl, a tire pressure determining apparatus is known which determines a pressure loss in a tire based on tire vibrations.
In der EP 0 895 880 A2 wird eine Vorrichtung zum Abschätzen des Luftdruckes eines Reifens offenbart, welche einen Temperatursensor umfasst, welcher die Außenlufttemperatur misst. Anhand der bestimmten Außenlufttemperatur werden Effekte der Temperatur auf die Resonanzfrequenz des Reifens korrigiert.EP 0 895 880 A2 discloses an apparatus for estimating the air pressure of a tire comprising a temperature sensor which measures the outside air temperature. Based on the determined outside air temperature, effects of the temperature on the resonance frequency of the tire are corrected.
Aufgabe der Erfindung ist es, ein Reifendruckuberwachungs- system für ein Kraftfahrzeug basierend auf der Auswertung der Reifenschwingungen bereitzustellen, bei welchem der Ein- fluss der Temperatur berücksichtigt wird.The object of the invention is to provide a tire pressure monitoring system for a motor vehicle based on the evaluation of the tire vibrations, in which the influence of the temperature is taken into account.
Diese Aufgabe wird erfindungsgemaß durch das Verfahren nach Anspruch 1 gelost.This object is achieved according to the invention by the method according to claim 1.
Der Erfindung liegt der Gedanke zugrunde, eine Kompensationsgroße für mindestens eine Druckverlustanalysegroße, welche durch Analyse des Torsionseigenschwingverhaltens mindestens eines Reifens gewonnen wird, zu bestimmen. Dabei hangt diese Kompensationsgroße von einer mittels eines Temperaturmodells berechneten Reifentemperatur ab.The invention is based on the idea of determining a compensation quantity for at least one pressure loss analysis quantity, which is obtained by analyzing the torsional natural vibration behavior of at least one tire. In this case, this compensation quantity depends on a tire temperature calculated by means of a temperature model.
Bevorzugt wird für die Kompensationsgroße ein Quotient aus Änderung der Druckverlustanalysegroße zu Temperaturanderung verwendet. Dieser gibt direkt den Einfluss der Temperatur auf die Druckverlustanalysegroße wieder. Ebenso ist es bevorzugt, dass für jede Druckverlustanalysegröße eine Kompensationsgröße ermittelt wird. So ist eine individuelle Korrektur jeder Druckverlustanalysegröße möglich.Preferably, a quotient of change in the pressure loss analysis quantity to temperature change is used for the compensation quantity. This directly reflects the influence of temperature on the pressure loss analysis size. It is likewise preferred that a compensation variable is determined for each pressure loss analysis variable. Thus, an individual correction of any pressure loss analysis size is possible.
Bei der Druckverlustanalysegröße handelt es sich bevorzugt um eine bei einer Eigenfrequenzanalyse bestimmte Eigenfrequenz oder Eigenfrequenzverschiebung.The pressure loss analysis variable is preferably a natural frequency or natural frequency shift determined during a natural frequency analysis.
Es ist jedoch auch bevorzugt, dass es sich bei der Druckverlustanalysegröße um eine Größe, welche sich aus Frequenzverschiebung und weiteren spektrenbeschreibenden Größen ergibt, oder eine den Reifen beschreibende Federkonstante handelt.However, it is also preferable that the pressure loss analysis quantity is a quantity resulting from frequency shift and other spectrally describing quantities, or a spring constant describing the tire.
Gemäß einer bevorzugten Ausführungsform berücksichtigt das verwendete Temperaturmodell mindestens eine der folgenden Wärmemengenänderungen, um die Reifentemperatur zu berechnen:According to a preferred embodiment, the temperature model used takes into account at least one of the following heat quantity changes to calculate the tire temperature:
Wärmefluss durch Walkarbeit des Reifens (QWaik), WärmeflussHeat flow through flexing of the tire (Q Waik ), heat flow
durch Konvektion ( QCθnvection ) ι Wärmefluss durch Abstrahlungby convection (Q Cθnvect i on ) ι heat flow through radiation
des Reifens ( QRadχatχon ) / Wärmefluss durch Wärmeeintrag desof the tire (Q Rad χ at χ on ) / Heat flow due to heat input of the tire
Fahr z euge s ( QvehxcleCondxtiLon ) •Driving License (QvehxcleCondxtiLon) •
In einer Weiterbildung der Erfindung wird/werden die Kompensationsgröße (n) eingelernt, wobei zum Einlernen der Kompensationsgröße (n) die Druckverlustanalysegröße (n) zusammen mit der/den berechneten Reifentemperatur (en) über ein oder mehrere Fahrten betrachtet wird/werden. Durch das Einlernen ü- ber eine längere Zeitspanne kann eine ausreichende statisti- sehe Relevanz des Ergebnisses sichergestellt werden.In one development of the invention, the compensation variable (s) is / are taught in, the pressure loss analysis variable (s) being considered together with the calculated tire temperature (s) via one or more journeys for teaching the compensation variable (s). Learning over a longer period of time can provide sufficient statistical see the relevance of the result.
Bevorzugt wird die Reifentemperatur durch zeitliche Integration aus der mindestens einen Wärmemengenänderung bestimmt wird. Besonders bevorzugt wird die Reifentemperatur durch Integration aller Wärmemengenänderungen bestimmt.Preferably, the tire temperature is determined by temporal integration of the at least one heat quantity change. Particularly preferably, the tire temperature is determined by integration of all heat quantity changes.
Zur Berechnung der Reifentemperatur werden bevorzugt mindestens zwei der folgenden Größen herangezogen: AußentemperaturTo calculate the tire temperature, at least two of the following variables are preferably used: outside temperature
(TAussen) t Temperatur in einem Steuergerät, Motor- Ansauglufttemperatur, Kühlmitteltemperatur, Motortemperatur(T Outside ) t Temperature in one control unit, engine intake air temperature, coolant temperature, engine temperature
(TEngine) t Bremsentemperatur (TBrake) t Standzeit des Fahrzeugs, Fahrprofil seit Einschalten der Zündung, insbesondere Fahrzeuggeschwindigkeit (v) , Gierrate, Querbeschleunigung, Antriebsmoment und/oder gefahrene Kilometer, Umgebungssensorinformationen, insbesondere Regensensor- und/oder Taupunktsensorinformationen .(T En gine) t brake temperature (T Br ake) t life of the vehicle, driving profile since switching on the ignition, in particular vehicle speed (v), yaw rate, lateral acceleration, drive torque and / or driven mileage, environment sensor information, in particular rain sensor and / or dew point sensor information.
Ein Vorteil des erfindungsgemäßen Verfahrens ist die verringerte Fehlwarngefahr bzw. Nichtwarngefahr bei Druckverlust.An advantage of the method according to the invention is the reduced risk of false alarms or the risk of non-warning in the event of pressure loss.
Die Erfindung betrifft auch ein Computerprogrammprodukt, welches einen Algorithmus nach dem vorstehend beschriebenen Verfahren definiert.The invention also relates to a computer program product which defines an algorithm according to the method described above.
Weitere bevorzugte Ausführungsformen ergeben sich aus den Unteransprüchen und der nachfolgenden Beschreibung an Hand von Figuren.Further preferred embodiments will become apparent from the subclaims and the following description with reference to figures.
Es zeigen Fig. 1 ein schematisches Blockschaltbild zu einer Temperaturkompensation in einer Frequenzanalyse, undShow it 1 is a schematic block diagram of a temperature compensation in a frequency analysis, and
Fig. 2 ein schematisches Blockschaltbild zu einer Reifentemperaturberechnung .2 is a schematic block diagram of a tire temperature calculation.
Die Reifentemperatur hat einen Einfluss auf den Druck im Reifen. Aus einer erhöhte Reifentemperatur folgt ein erhöhter Reifendruck, damit eine erhöhte Reifensteifigkeit sowie eine erhöhte Eigenfrequenz. Allerdings wird die Steifigkeit des Reifenmaterials (Gummi) ebenso durch die Temperatur be- einflusst. Eine erhöhte Temperatur ergibt ein weicheres Gummi, damit eine geringere Steifigkeit und eine geringere Eigenfrequenz. Es hat sich gezeigt, dass sich die beiden Effekte in ihrem Einfluss auf den Reifen und damit bevorzugt auf die Eigenfrequenz nicht kompensieren, sondern dass der Effekt abhangig von Material, Reifentemperatur und Innendruck ist. Dies fuhrt bei Fahrten mit hohen Temperaturschwankungen zu Veränderungen des Torsionsschwingungsverhal- tens eines Reifens, welche im Großenbereich der Änderungen bei einem Druckverlust liegen. Damit geht eine erhöhte Fehlwarngefahr bzw. Nichtwarngefahr bei Druckverlust einher.The tire temperature has an influence on the pressure in the tire. From an increased tire temperature follows an increased tire pressure, thus increased tire stiffness and increased natural frequency. However, the stiffness of the tire material (rubber) is also affected by the temperature. An increased temperature results in a softer rubber, thus a lower stiffness and a lower natural frequency. It has been shown that the two effects do not compensate for their influence on the tire and thus preferably on the natural frequency, but that the effect is dependent on material, tire temperature and internal pressure. This leads to changes in the torsional vibration behavior of a tire when driving with high temperature fluctuations, which are in the wide range of changes in a pressure loss. This is associated with an increased risk of false alarms or non-alarms in case of pressure loss.
Das erfindungsgemaße Verfahren wird in einem System zur indirekten Reifendruckuberwachung eingesetzt, in welchem eine Analyse des Eigenschwingverhaltens eines oder mehrerer Reifen durchgeführt wird. Hierbei wird für mindestens einen Reifen, bevorzugt für jeden Reifen, eine Druckverlustanaly- segroße bestimmt. Als Beispiel für eine Druckverlustanalyse- größe wird in der folgenden Beschreibung die Eigenfrequenzverschiebung f aus der Frequenzanalyse verwendet. Ebenso ist dies jedoch mit einer Druckverlustanalysegröße, welche sich aus Frequenzverschiebung und weiteren spektrenbeschreibenden Größen ergibt, wie es z.B. in der WO 2005/005174 Al näher beschrieben wird, möglich oder auch mit einer Federkonstante des Reifens, wie z.B. in der EP 0 895 880 A2 offenbart. Beispielsgemäß liegt für jedes Rad eine Frequenzverschiebung fvL/ fvR/ fm, ff« (VR: vorne rechts, HR: hinten rechts, VL: vorne links, HL: hinten links) vor.The inventive method is used in a system for indirect tire pressure monitoring, in which an analysis of the natural vibration behavior of one or more tires is performed. In this case, a pressure loss analysis size is determined for at least one tire, preferably for each tire. As an example of a pressure loss analysis size, the natural frequency shift f from the frequency analysis is used in the following description. However, this is also possible with a pressure loss analysis variable, which results from frequency shift and other spectrally describing variables, as described in greater detail in WO 2005/005174 A1, for example, or also with a spring constant of the tire, as for example in EP 0 895 880 A2 disclosed. For example, for each wheel there is a frequency shift fvL / fvR / fm, ff "(VR: front right, HR: right rear, VL: front left, HL: rear left).
In Fig. 1 ist ein schematisches Blockschaltbild eines beispielsgemäßen Verfahrens dargestellt, welches das oben genannte Problem des Reifentemperatureinflusses löst. Beispielsgemäß wird die Eigenfrequenz fk (dabei kann der Index k stehen für VL, VR, HL oder HR) des Reifens zusammen mit einer berechneten Reifentemperatur TReifen eingelernt. Aus diesem Ensemble wird eine Kompensationsgröße für den Temperaturein- fluss ermittelt, der auf die ermittelten Eigenfrequenzen fk angewendet wird. Zu Beginn, bevor ein Kompensationswert vorliegt, wird zunächst ein empirischer Mittelwert (z.B. -0.5 Hz/10 °C) als Grundkompensation 3 angenommen. Während des Einlernens wird dann aus verschiedenen Fahr-, Fahrzustands-, Fahrzeug- und Umweltinformationen Xn, wie z.B. Außentemperatur, Standzeit, Kühlmitteltemperatur, Fahrgeschwindigkeit, Fahrprofil etc., mit Hilfe eines Temperaturmodells 1 eine Reifentemperatur TReifen berechnet. Außerdem werden entsprechend die Eigenfrequenzen der Räder fVL, fVR, fHL, fHR bestimmt. Bei Vorliegen von Temperatur/Frequenz-Werten wird ein Korrekturfaktor 2 eingelernt. Dieser wird verwendet, um aus der Grundkompensation 3 einen aktuellen Temperaturkompensationswert 4 zu bestimmen, mit welchem die temperaturkompensierten Eigenfrequenzen f'VL, f'vR/ f%L, f'HR bestimmt werden.In Fig. 1 is a schematic block diagram of an exemplary method is shown, which solves the above-mentioned problem of Reifentemperatureinflusses. By way of example, the natural frequency f k (where the index k stands for VL, VR, HL or HR) of the tire is learned together with a calculated tire temperature T Rei f e n. From this ensemble a compensation quantity for the temperature influence is determined, which is applied to the determined natural frequencies f k . At the beginning, before a compensation value is present, an empirical mean value (eg -0.5 Hz / 10 ° C.) is assumed as basic compensation 3. During the learning, a tire temperature T Rei n e is then calculated from various driving, driving condition, vehicle and environmental information X n , such as the outside temperature, service life, coolant temperature, driving speed, driving profile, etc. with the aid of a temperature model 1. In addition, the natural frequencies of the wheels f VL , f VR , f HL , f HR are determined accordingly. If temperature / frequency values are present, a correction factor 2 is learned. This is used to get out of the Basic compensation 3 to determine a current temperature compensation value 4, with which the temperature-compensated natural frequencies f ' VL , f'vR / f% L, f' HR are determined.
Beim Einlernen des Korrekturfaktors 2 wird eine Bewertung der Streubreite der Temperatur TReifen durchgeführt. Der Korrekturfaktor 2 wird erst dann akzeptiert, wenn die Streubreite des gelernten Temperatur/Frequenz-Ensembles in Bezug auf die Temperatur TReifen (z.B. niedrigste Temperatur zur höchsten Temperatur und ausreichende Anzahl von Wertepaaren über diesem Bereich) groß genug ist.When learning the correction factor 2, an evaluation of the spread of the temperature T Rei f e n is performed. The correction factor 2 is only accepted if the spread of the learned temperature / frequency ensemble with respect to the temperature T Rei f e n (eg lowest temperature to highest temperature and sufficient number of value pairs above this range) is large enough.
Das Temperaturmodell 1 verwendet zur Berechnung der Reifentemperatur TReifen beispielsgemäß die folgenden Informationen:The temperature model one used to calculate the tire temperature T Rei fen example according to the following information:
• Außentemperatur TAussen, erhältlich entweder über einen Temperatursensor im Steuergerät oder aber über CAN Botschaften, wie z.B. Kombiaußentemperatur und Ansauglufttemperatur,• Outside temperature T outside , available either via a temperature sensor in the control unit or via CAN messages, such as outside air temperature and intake air temperature,
• Standzeit des Fahrzeugs: Abschätzung mitunter über die Kühlmitteltemperatur oder Motortemperatur TEngine in Kombination mit der Außentemperatur TAussen, falls keine Standzeit zur Verfügung steht,• Service life of the vehicle: Estimation sometimes via the coolant temperature or engine temperature T Engine in combination with the outside temperature T Outside , if no service life is available,
• Fahrprofil, erhältlich aus dem Geschwindigkeitssignal v, Gierrate bzw. Querbeschleunigung sowie Antriebsmoment. Darüber hinaus berechnete Größen wie z.B. gefahrene Kilometer seit „Zündung-An", und• Driving profile, available from the speed signal v, yaw rate or lateral acceleration and drive torque. In addition, calculated quantities such as e.g. Mileage since "Ignition-On", and
• Regensensor- bzw. Taupunktsensorinformationen, um auf die Nässe der Straße rückschließen zu können. Diese Informationen werden mit Hilfe eines Temperaturmodells 1 verknüpft, welches in einem ersten Ausführungsbeispiel den• Rain sensor or dew point sensor information to help you understand the wetness of the road. This information is linked by means of a temperature model 1, which in a first embodiment the
• • •• • •
Wärmefluss Q durch Walkarbeit QWaik' Konvektion QCθnvection undHeat flow Q through flexing Q Wa i k 'convection Q Cθnvect i on un d
Strahlungswärme QRaciiation bilanziert, und daraus eine Reifen-Radiation heat Q Rac ii at i on account, and from this a tire
temperatur berechnet. In einem weiteren Term Qvehiciecondition fur Umweltbedingungen werden Einflüsse des Fahrzeugs, wie z.B. Bremsentemperatur und Motortemperatur, berücksichtigt.temperature calculated. In another term Qv eh i c i e i t i c ond f ur on environmental conditions influences the vehicle, such as brake temperature and engine temperature, taken into account.
Mögliche Berechnungsgleichungen sind: Strahlung/Strahlungswärme : n _ A.(T4 _„4 \_ (T4 _„4 \Possible calculation equations are: Radiation / radiant heat: n _ A. ( T 4 _ "4 \ _ ( T 4 _" 4 \
^Radiation t u .-- \-i-Aus seri Reifen / us V-1AuS sen -"-Reifen /^ Radiation t u - - \ - i - From seri Tires / u s V- 1 Au S sen - "- Tires /
Konvektion :Convection:
Q Convection = αk ■ Vv ■ ( ΥConvection Q = α k ■ ■ Vv (Υ
'r 1T Aussen Reifen,' r 1 T Outside Tires,
Walkarbeit :Flexing work:
QWalk =f-m-g-v = f-Fz-vQ Walk = fmgv = fF z -v
Fahrzeugbedingungen/Fahrzeugwärmeeintrag :Vehicle conditions / vehicle heat input:
O = f CT T 1IO = f CT T 1 I
VehicleCondition ^ v xBrake ' Angine ' 'VehicleCondition ^ vx Brake 'Angine''
MitWith
8: Emissionsgrad,8: emissivity,
G: Stefan-Boltzmann-Konstante,G: Stefan Boltzmann constant,
A: strahlende Oberfläche des Reifens, CCs : Proportionalitätskonstante der Strahlungswärme, αk: Proportionalitätskonstante der Konvektion, f: Proportionalitätskonstante des Rollwiderstandes,A: radiating surface of the tire, CCs: proportionality constant of radiant heat, α k : constant of proportionality of convection, f: proportionality constant of rolling resistance,
Fz: Radlast, v: Geschwindigkeit,F z : wheel load, v: speed,
TAussen: Außentemperatur,T outside : outside temperature,
TReifen: Reifentemperatur, und f (TBrake, TEngine, ...) : Funktion der Bremsentemperatur TBrake, derT Rei fen: tire temperature, and f (t ake Br, T Engine, ...): a function of brake temperature T Br ake, the
Motortemperatur TEngine und weiterer Größen. Engine temperature T engine and other sizes.
Die Reifentemperatur TReifen kann dann durch Integration der Wärmemengenänderungen berechnet werden gemäß :The tire temperature T Tire can then be calculated by integrating the heat quantity changes according to:
-'-Reifen ~ -^ ' ^Reifen ' J IV Qconvection "■" Ü'Radiation """ Q'walk """ Q'vehideCondition U P- 1 + -Lgtart-'- Tires ~ - ^ '^ Tire ' J IV Qconvection "■" Ü ' Radiation " "" Q ' walk " "" Q ' vehideCondition U P- 1 + -Lgtart
Mit CReifen: Wärmekapazität des Reifen und Tstart: Startwert.With CReifen: heat capacity of the tires and T st art: starting value.
In Fig. 2 ist ein beispielsgemäßes Verfahren zur Berechnung der Reifentemperatur TReifen nach obiger Gleichung schematisch dargestellt. Aus Außentemperatur TAussen, Fahrgeschwindigkeit v, Bremsentemperatur TBrake, Motortemperatur TEngine und einem Startwert Tstart für die Reifentemperatur werden die vier Wär-FIG. 2 schematically illustrates an example method for calculating the tire temperature T tire according to the above equation. From outside temperature T outside , driving speed v, brake temperature T brake , engine temperature T engine and a starting value T st a r t for the tire temperature, the four heat
• • • • meflussbeitrage QWaik' Qconvection r QRadiation und Qvehiciecondition be¬ rechnet, in Block 5 aufaddiert, in Block 6 durch die Wärme¬ kapazität CReifen geteilt und in Block 7 über die Zeit t integ¬ riert. Die resultierende Reifentemperatur TReifen wird zur Be-• • • • Flow contribution Q Wa ik 'Qconvection r QRadiation and Qvehiciecondition be ¬ rechnet, added up in block 5, divided in block 6 by the heat ¬ capacity C R e f e n e and integ ¬ in block 7 over the time t. The resulting tire temperature T Tire is used to
rechnung neuer Wärmeflussbeiträge Qconvection r QRadiation verwen- det .calculation of new heat flow contributions Qc onvect on Q Rad i at i on use det.
In einem besonders einfachen Ausführungsbeispiel wird derIn a particularly simple embodiment of the
Strahlungsanteil QRadiat;LOri vernachlässigt . Als Ausgleich für die damit fehlende Temperaturabnahme wird eine minimale Geschwindigkeit v als Eingang für die Konvektionsgleichung angenommen .Radiation fraction Q Radiat; LOri neglected. To compensate for the lack of temperature decrease, a minimum velocity v is assumed to be the input for the convection equation.
Zur Bestimmung eines Startwertes Tstart müssen Plausibilisie- rungswerte aus der Standzeit herangezogen werden. St to determine a start value T art feasibility check must approximate values are drawn from the life.

Claims

Patentansprüche claims
1. Verfahren zur indirekten Reifendrucküberwachung, in welchem eine Analyse des Eigenschwingverhaltens mindestens eines Reifens durchgeführt wird und mindestens eine Druckverlustanalysegröße (fVL, fvR, fm, fm) t insbesondere eine Eigenfrequenz, bestimmt wird, wobei eine Temperaturkompensation (4) der Druckverlustanalysegröße (fVL, fVR, fHL/ £HR) durchgeführt wird, dadurch gekennzeichnet, dass zur Bestimmung einer Kompensationsgröße (2), insbesondere des Quotienten aus Änderung der Druckverlustanalysegröße und Temperaturänderung, eine mittels eines Temperaturmodells (1) berechnete Reifentemperatur (TReifen) verwendet wird.1. A method for indirect tire pressure monitoring, in which an analysis of the natural vibration behavior of at least one tire is performed and at least one pressure loss analysis variable (f V L, fvR, fm, fm) t, in particular a natural frequency, is determined, wherein a temperature compensation (4) of the pressure loss analysis variable ( f V L, f V R, fHL / HR HR), characterized in that for determining a compensation quantity (2), in particular the quotient of change in the pressure loss analysis variable and temperature change, a tire temperature (T tire calculated by means of a temperature model (1) ) is used.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass das Temperaturmodell (1) mindestens eine der folgenden Wärmemengenänderungen berücksichtigt: Wärmefluss durch2. The method according to claim 1, characterized in that the temperature model (1) takes into account at least one of the following heat quantity changes: heat flow through
• Walkarbeit des Reifens (QWaik), Wärmefluss durch Konvek-• flexing of the tire (Q Waik ), heat flow through convection
tion ( Qconvection ) ι Wärmefluss durch Abstrahlung des Rei-tion (Qc onvect i on ) ι heat flow through radiation of the rice
fens ( QRadiation ) r Wärmefluss durch Wärmeeintrag des Fahr-fens (Q Rad i at i on ) r heat flow through heat input of the vehicle
Z euge s ( QvehideCondition ) •Z euge s (QvehideCondition) •
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass zum Einlernen der Kompensationsgröße die Druckverlustanalysegröße (fVL, fvR, fm, fHR) r insbesondere Eigenfrequenz, zusammen mit der berechneten Reifentempe- ratur (TReifen) über ein oder mehrere Fahrten betrachtet wird.3. The method according to claim 1 or 2, characterized in that for learning the compensation value, the pressure loss analysis variable (f V L, fvR, fm, fHR) r, in particular natural frequency, together with the calculated Tempe- (T Tire ) over one or more journeys.
4. Verfahren nach mindestens einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass die Reifentemperatur (TReifen) durch zeitliche Integration aus der mindestens einen4. The method according to at least one of claims 1 to 3, characterized in that the tire temperature (T tire ) by temporal integration of the at least one
• • •• • •
Wärmemengenänderung ( QWalk , Qconvection , QnacuatiLon ,Change in heat quantity (Q Walk , Qc on v ect i on , Qn ac u at i Lon ,
••
Qvehiciecondition)/ insbesondere aus allen Wärmemengenänderun¬ gen, bestimmt wird.Qv eh i c i e c ond i t i on ) / in particular from all Wärmemengenänderun ¬ conditions, is determined.
5. Verfahren nach mindestens einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass die Reifentemperatur (TReifen) unter Berücksichtigung mindestens zweier der folgenden Größen berechnet wird: Außentemperatur (TAussen) , Tempera¬ tur in einem Steuergerät, Motor-Ansaugluft-temperatur, Kühlmitteltemperatur, Motortemperatur (TEngine) , Bremsentemperatur (TBrake) , Standzeit des Fahrzeugs, Fahrprofil seit Einschalten der Zündung, insbesondere Fahrzeuggeschwindigkeit (v) , Gierrate, Querbeschleunigung, Antriebsmoment und/oder gefahrene Kilometer, Umgebungssensorinformationen, insbesondere Regensensor- und/oder TaupunktsensorInformationen .5. The method according to at least one of claims 1 to 4, characterized in that the tire temperature (T tire ) is calculated taking into account at least two of the following variables: outside temperature (T outside ), tempera ¬ tur in a control unit, engine intake air temperature , Coolant temperature, engine temperature (T Engine ), brake temperature (T Br ake), service life of the vehicle, driving profile since the ignition is switched on, in particular vehicle speed (v), yaw rate, lateral acceleration, drive torque and / or driven kilometers, environment sensor information, in particular rain sensor and / or dew point sensor information.
6. Computerprogrammprodukt, dadurch gekennzeichnet, dass dieses einen Algorithmus definiert, welcher ein Verfahren gemäß mindestens einem der Ansprüche 1 bis 5 um- fasst . 6. Computer program product, characterized in that it defines an algorithm which comprises a method according to any one of claims 1 to 5.
EP06819461A 2005-11-14 2006-11-14 Indirect tire pressure monitoring method Withdrawn EP1948454A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102005054556 2005-11-14
DE102006053825A DE102006053825A1 (en) 2005-11-14 2006-11-14 Method for indirect tire pressure monitoring
PCT/EP2006/068442 WO2007054586A1 (en) 2005-11-14 2006-11-14 Indirect tire pressure monitoring method

Publications (1)

Publication Number Publication Date
EP1948454A1 true EP1948454A1 (en) 2008-07-30

Family

ID=38022988

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06819461A Withdrawn EP1948454A1 (en) 2005-11-14 2006-11-14 Indirect tire pressure monitoring method

Country Status (4)

Country Link
US (1) US20080223124A1 (en)
EP (1) EP1948454A1 (en)
DE (1) DE102006053825A1 (en)
WO (1) WO2007054586A1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006032212A1 (en) * 2005-08-18 2007-03-08 Continental Teves Ag & Co. Ohg Method for automatically initializing an indirectly measuring tire pressure monitoring system
DE102007007672B4 (en) 2006-02-15 2023-05-11 Continental Aktiengesellschaft Method for indirect tire pressure monitoring
DE102007029870A1 (en) * 2007-06-28 2009-01-02 Continental Teves Ag & Co. Ohg Tire condition monitoring method and apparatus
DE102008052282A1 (en) * 2008-10-18 2010-04-29 Bayerische Motoren Werke Aktiengesellschaft Vehicle e.g. passenger car, controlling method, involves determining temperature-dependent characteristics of tires, and controlling and/or regulating vehicle based on determined temperature-dependent characteristics
US8573045B2 (en) * 2011-10-28 2013-11-05 Infineon Technologies Ag Indirect tire pressure monitoring systems and methods

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4574267A (en) * 1982-05-06 1986-03-04 Trw Inc. Tire pressure warning system
US5553491A (en) * 1991-11-11 1996-09-10 Nippondenso Co., Ltd. Tire air pressure detecting device
JP3300601B2 (en) * 1996-05-23 2002-07-08 トヨタ自動車株式会社 Tire pressure detector
EP0895880B1 (en) * 1997-08-08 2004-06-09 Denso Corporation Apparatus for estimating tire air pressure
DE10331585A1 (en) * 2003-07-08 2005-03-31 Continental Teves Ag & Co. Ohg Method for determining the internal pressure of a vehicle tire
US20050150183A1 (en) * 2004-01-09 2005-07-14 Hettler Neil R. Insulation system with variable position vapor retarder

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2007054586A1 *

Also Published As

Publication number Publication date
WO2007054586A1 (en) 2007-05-18
US20080223124A1 (en) 2008-09-18
DE102006053825A1 (en) 2007-06-06

Similar Documents

Publication Publication Date Title
EP1948453B1 (en) Method for indirectly monitoring a tire pressure
EP2170631B1 (en) Method and device for monitoring the state of tyres
DE10036580B4 (en) Method and device for vehicle control and / or driver information in tire pressure loss
DE102005004910A1 (en) Indirect monitoring of a vehicle tire pressures, with a learning stage to establish test values, uses natural torsion frequencies and oscillation behavior to give an early warning of tire pressure changes
DE102012218426B4 (en) Method, control unit and system for determining a, a state of at least one component of a motor vehicle characterizing parameter
WO2019102036A1 (en) Method, control device, and system for determining a profile depth of a profile of a tire
DE60113282T2 (en) DEVICE FOR PREDICTING A TIRE PLATTER
DE102017207620B4 (en) Method and device for determining wheel loads on wheels of a vehicle
WO2005063511A1 (en) Method for monitoring the pressure of motor vehicle tyres
DE102018117680A1 (en) Determining the state of health of the damper by means of indirect measurements
DE102008047750A1 (en) Driver assistance system for vehicle, has module for analysis of torsional vibration of wheel of vehicle and for generating estimated value of coefficient of friction on basis of analysis
DE102013220882B4 (en) Method, control unit and system for determining a tread depth of a profile of at least one tire
EP1948454A1 (en) Indirect tire pressure monitoring method
DE102016112930A1 (en) Apparatus and method for controlling a tire pressure taking into account a low pressure situation
DE102017201519A1 (en) A method and system for determining a wear condition of at least one tire
DE102005014099A1 (en) Method for determining of absolute rolling circumference of wheels of motor vehicle entails determining absolute vehicle speed and absolute rolling circumference of four wheels by using time difference between vibrations
DE102016112809A1 (en) Apparatus and method for controlling tire pressure using a mass of a vehicle
WO2001060644A1 (en) System for detecting the optimum tyre inflation pressure
DE102020104928A1 (en) Method and device for determining the condition of a vehicle tire
WO2004054824A1 (en) Method for indirectly identifying the loss of pressure on a motor vehicle wheel
DE102005048534A1 (en) Mechanical component e.g. brake, monitoring method for e.g. commercial vehicle, involves identifying imminent malfunction of brake based on value, controlling brake or other device such that instantaneous load of brake is reduced or limited
DE102022111116A1 (en) Methods, devices and computer program products for determining the severity of deflation in a tire
EP2805861A2 (en) Method for monitoring vehicles using mass measurements
DE102016211361A1 (en) Apparatus and method for controlling a tire pressure according to a tire shop
EP1893460A1 (en) Method and device for the detection of a roadway having a low coefficient of friction

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20080415

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR

DAX Request for extension of the european patent (deleted)
RBV Designated contracting states (corrected)

Designated state(s): DE FR

17Q First examination report despatched

Effective date: 20111108

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20160916