DE102017131160A1 - Method for determining a center of gravity height of a motor vehicle - Google Patents

Abstract

A method for determining a center of gravity height of a motor vehicle comprising the following method steps: A) determining a reference body height z of the vehicle and at least one altitude sensor Z, Z, Z, B) determining a body height change δeines a wheel of the wheel associated reference body height z of the vehicle and at least one height sensor height Z) determining a longitudinal acceleration of the vehicle; C2) determining a pitch angle θ; C3) determining a pitch angular velocity θ / t; C4) determining a pitch angular acceleration θ / t; and / orD1) determining a lateral acceleration of the vehicle D2) determining a roll angle θD3) determining a roll angular velocity θ / tD4) determining a roll angular acceleration θ / t; and E) calculating a centroid hunter using the determined parameters A, B, C1, C2, C3, C4 and / or A, B, D1, D2, D3, D4.

Description

The invention relates to methods for determining a center of gravity height of a motor vehicle according to the independent claim.

The invention relates to the technical field of methods for operating a vehicle, in which the mode of vehicle operation is changed taking into account the center of gravity. In this case, for example, due to the transport of objects on the vehicle roof, such as a ski box or a roof box, the vehicle center of gravity can change such that an adjustment of the settings of a vehicle dynamics controller, for example. ESP (Electronic Stability Program) becomes necessary because the controller does not work reliably with the original values for the vehicle's center of gravity.

It is from the DE 10 2006 002 973 A1 A method is known in which a center of gravity increase of the vehicle, due to a roof load on the vehicle, is detected, and the information obtained in an adjustment of the driving behavior of the vehicle with a view to avoiding tipping over of the vehicle are taken into account. The determination of the roof load is started with the beginning of the loading of the roof load on the vehicle. Depending on the information collected, a change in settings of an electronic vehicle dynamics control system of the vehicle is activated. For this purpose, a switch is actuated when installing a roof rack. If the manual operation is not triggered by a poor installation or if no proper roof rack is used, which causes the triggering of the switch, the vehicle retains the original settings even with increased roof load (or changed focus), especially with regard to the function of the ESP , which relies on the vehicle's center of gravity, is disadvantageous.

Furthermore, from the prior art with the DE 10 247 993 B4 a method for determining a center of gravity height of a motor vehicle, in which during a predefined "quasi-static" driving situation, the center of gravity is determined based on the rolling motion. For this purpose, the center of gravity height of the motor vehicle is determined from a variable representing the roll motion and a variable representing the lateral acceleration. The problem with this method is that the reliable determination of the center of gravity can only take place in certain driving states. If no or very little rolling motion occurs, a change in the center of gravity may not be recognized, for example, when no winding road is traveled.

It is the object of the present invention to provide a method for determining a center of gravity height of a motor vehicle, which overcomes the disadvantages known from the prior art, and in particular reliably and accurately functions regardless of the driving situation or at least in a variety of driving situations.

This object is achieved by a method for determining a center of gravity height of a motor vehicle according to the independent claim. Advantageous aspects form the subject of the respective subclaims.

• A) Ermitteln einer Referenzaufbauhöhe z_ref des Fahrzeugs und mindestens einer Höhenstandsensorhöhe Z_FL, Z_FR, Z_RL, Z_RR;
• B) Ermitteln einer Aufbauhöhenänderung δ_rad eines Rades von einer dem Rad zugeordneten Referenzaufbauhöhe z_ref des Fahrzeugs und mindestens einer Höhenstandssensorhöhe Z_FL, Z_FR, Z_RL, Z_RR;
• C1) Ermitteln einer Längsbeschleunigung a_x des Fahrzeugs;
• C2) Ermitteln eines Nickwinkels θ_y;
• C3) Ermitteln einer Nickwinkelgeschwindigkeit θ_y/t;
• C4) Ermitteln einer Nickwinkelbeschleunigung θ_y/t²; (und/)oder
• D1) Ermitteln einer Querbeschleunigung a_y des Fahrzeugs;
• D2) Ermitteln eines Wankwinkels θ_x
• D3) Ermitteln einer Wankwinkelgeschwindigkeit θ_x/t
• D4) Ermitteln einer Wankwinkelbeschleunigung θ_x/t²; und
• E) Berechnen einer Schwerpunktshöhe h_sp unter Verwendung der ermittelten Parameter A, B, C1, C2, C3, C4 (und/)oder A, B, D1, D2, D3, D4.

The invention comprises a method for determining a center of gravity height h _{sp of} a motor vehicle with the following method steps:

• A) determining a reference body height z _{ref of} the vehicle and at least one height sensor height Z _FL , Z _FR , Z _RL , Z _RR ;
• B) determining a body height change δ _{rad of} a wheel from a reference elevation height z _{ref of} the vehicle associated with the wheel and at least one altitude sensor elevation Z _FL , Z _FR , Z _RL , Z _RR ;
• C1) determining a longitudinal acceleration a _{x of} the vehicle;
• C2) determining a pitch angle θ _y ;
• C3) determining a pitch angular velocity θ _y / t;
• C4) determining a pitch angular acceleration θ _y / t ² ; (and or
• D1) determining a lateral acceleration a _{y of} the vehicle;
• D2) determining a roll angle θ _x
• D3) determining a roll angular velocity θ _x / t
• D4) determining a roll angular acceleration θ _x / t ² ; and
• E) calculating a centroid height h _sp using the determined parameters A . B . C1 . C2 . C3 . C4 (and or A . B . D1 . D2 . D3 . D4 ,

In this way, a method of determining a center of gravity height becomes h _sp of a motor vehicle, which determines the center of gravity height of the motor vehicle both using a variable representing the roll motion and a quantity representing the lateral acceleration, as well as using a size representing the pitching motion and a quantity representing the longitudinal acceleration. Thus, a method for determining the height of the center of gravity is provided that in a Variety of driving situations reliable and accurate.

für die Längsrichtung mit C1, C2, C3, C4;
(und/)oder $$\frac{K_{ef{f}_{rad}}{b}_{fzg}}{m_{Fzg}}{\delta }_{rad}=a_y{h}_{sp}+fehler\left(\frac{\mathrm{\theta }x}{t^2},\frac{\mathrm{\theta }x}{\text{t}},\mathrm{\theta }\text{x}\text{,}{\dot{h}}_{sp}\right)$$

für die Querrichtung mit C1, C2, C3, C4;
wobei

• K_{eff rad} = Effektiv Federrate für die jeweilige Feder [N/m],
• L_fzg = Radstand [m],
• m_Fzg = Fahrzeugmasse [Kg],
• b_fzg = Fahrzeugspurweite [m],
• a_x = Fahrzeuglängsbeschleunigungssensorwert [ms^-2] und
• a_y = Fahrzeugquerbeschleunigungssensorwert [ms^-2] ist.

According to a preferred aspect, the center of gravity height h _sp using the following equations (where the vehicle longitudinal acceleration and vehicle lateral acceleration are calculated in the inertial coordinate system): $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_x{H}_{sp}+feHler\left(\frac{\mathrm{<figure-callout\; id="2"\; label="\theta \; y\; t"\; filenames="DE102017131160A1\_0022.png"\; state="\{\{state\}\}">\theta \; </figure-callout>}y}{t^{}}.\frac{\mathrm{\theta }y}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right)$$

for the longitudinal direction with C1 . C2 . C3 . C4 ;
(and or $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_y{H}_{sp}+feHler\left(\frac{\mathrm{\theta }x}{{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="DE102017131160A1\_0022.png"\; state="\{\{state\}\}">t</figure-callout>}}^2}.\frac{\mathrm{\theta }x}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

for the transverse direction with C1 . C2 . C3 . C4 ;
in which

• K _{eff wheel} = Effective spring rate for the respective spring [N / m],
• L _fzg = wheelbase [m],
• m _Fzg = vehicle mass [Kg],
• b _fzg = vehicle _gauge [m],
• a _x = vehicle longitudinal acceleration sensor ^value [ms ^-2 ] and
• a _y = vehicle lateral ^acceleration sensor ^value [ms ^-2 ].

This calculation allows a determination of the center of gravity height h _sp taking into account an error term that represents the current driving state or the rolling motion and / or the pitching motion.

Preferably, the method further comprises the method step F1 ) Determining a vehicle longitudinal speed V _x and / or vehicle longitudinal acceleration v̇ _x , wherein the center of gravity h _sp calculated using the following equation (non-inertial coordinate system, eg with GPS data): $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}={\dot{v}}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{y}}{t^2}.\frac{\mathrm{\theta }\text{y}}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right),$$

With this determination of the center of gravity height, the error term can be taken into account and thus the calculation variant can be compared with other calculation variants and a faulty calculation variant can be identified and selected.

Another technically preferred aspect provides that the method further comprises the method step F2 ) Determining a vehicle lateral velocity V _y and / or vehicle lateral acceleration v̇ _y (non-inertial coordinate system). In this way, the center of gravity can be determined analogously to the longitudinal direction.

It is also preferred that the method further comprises the method step G ) Determining a vehicle vertical acceleration a _z . Thus, the determined value for the center of gravity height can be corrected or determined more precisely.

Another advantageous aspect is the method steps H1 ), with determining a yaw rate ω _z and H2 ) determine a centrifugal acceleration ω _z v _x, where the center of gravity h _sp is calculated from the following equation (vehicle lateral acceleration / centrifugal acceleration from non-inertial coordinate system) $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}={\omega }_z{v}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{<figure-callout id="2" label="x t" filenames="DE102017131160A1\_0022.png" state="{{state}}">x </figure-callout>}}{t^{}}.\frac{\mathrm{\theta }\text{x}}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

Here, too, results in a further error term, which is compared with the Fehlerterm other calculation methods to advantageously determine the vehicle's center of gravity as accurately and reliably.

Another particularly preferred aspect provides that the method further comprises the method step "I) determining a damper energization VL . VR . HL . MR "Includes. The damper energization allows additional correction.

Another advantageous aspect provides method step "J) determining a door status T". Thus, the method may be triggered at a time when the doors are locked and the center of gravity does not change due to passengers getting in and out during vehicle movement.

It is particularly advantageous if the method further comprises method step K) determining a road surface roughness degree F. Thus, the procedure can be suspended if the vehicle is traveling on bumpy roads and the detection of the vehicle's center of gravity is inaccurate.

• 1. Bereitstellen eines Steuergeräts in dem Fahrzeug;
• 2. Bereitstellen von mindestens einem mit dem Steuergerät verbundenen Sensor zur Ermittlung eines Fahrzeugparameters;
• 3. Starten des Steuergeräts und initiales ermitteln, ob eine Schwerpunktshöhe h_sp gespeichert vorliegt;
• 4. Entscheidung, ob
• 4a) Gewichtsbestimmung;
• 4b) Federratenbestimmung;
• 4c) Gewichtsbestimmung und Federratenbestimmung vorliegt und für den Fall: JA: erfolgt eine Berechnung verschiedener Parameter, wie „Masse“ und „Federrate“
• Bei: 4a) $$m_{Fzg}^{k+1}=m_{Fzg}^k+\mathrm{\Delta }{m}_{Fzg}$$
  
• Bei: 4b) $$K_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
  
• Bei 4c) $$m_{Fzg}^{k+1}=m_{Fzg}^k+\mathrm{\Delta }{m}_{Fzg}\text{\&\& }{K}_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
  

It is particularly advantageous if the above-described method further comprises the following method steps:

• 1. providing a control device in the vehicle;
• 2. providing at least one sensor connected to the control unit for determining a vehicle parameter;
• 3. Start the controller and initially determine if a center of gravity height h _sp stored exists;
• 4. Decide if
• 4a) weight determination;
• 4b) spring rate determination;
• 4c) weight determination and spring rate determination is present and in the case: YES: a calculation of various parameters, such as "mass" and "spring rate" is carried out
• At: 4a) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}$$
  
• At: 4b) $$K_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
  
• At 4c) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}\text{\&\&}{K}_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
  

No: the height of the center of gravity is calculated h _sp as described above.

Thus, the advantages in determining the center of gravity height, in particular on a control device already present in the vehicle, can be realized in the form of a method for operating a motor vehicle.

Particularly advantageous is the center of gravity h _sp compared with a default value for the center of gravity height h ₀ . For example, from a certain change, a load, such as a roof load, can be detected. It can also be determined whether a change in the setting of a vehicle dynamics control system must be made when a predetermined threshold is exceeded.

According to another aspect, the center of gravity becomes h _sp is compared with a previously stored center of gravity height h to determine an increase or decrease in the center of gravity height Δh _sp . Thus, a dynamic at the height of the center of gravity can be determined in order to carry out changes in the setting of a driving dynamics control system.

At least one vehicle dynamics control system ABS / ESP / Quattro-Sport / EFP is particularly preferred on the basis of the ascertained center of gravity height h _sp set.

• 1 ein Blockdiagramm zum Ablauf des Verfahrens zur Ermittlung einer Schwerpunktshöhe eines Kraftfahrzeugs; und
• 2 ein Kraftfahrzeug zum Betrieb unter Verwendung eines Verfahrens wie im Zusammenhang mit 1 beschrieben.

In the following the invention will be explained in more detail with reference to FIGS. Showing:

• 1 a block diagram of the process of determining a center of gravity height of a motor vehicle; and
• 2 a motor vehicle for operation using a method as associated with 1 described.

• A) Ermitteln einer Referenzaufbauhöhe z_ref des Fahrzeugs und mindestens einer Höhenstandssensorhöhe Z_FL, Z_FR, Z_RL, Z_RR. In diesem Verfahrensschritt kann die Höhenstandssensorhöhe Z_FL, Z_FR, Z_RL, Z_RR von (mindestens) einem Rad oder von (mindestens) einer Achse ermittelt werden. Zum Beispiel kann die Referenzaufbauhöhe mit einem (auf die Fahrbahn gerichteten) Abstandssensor ermittelt werden.
• B) Ermitteln einer Aufbauhöhenänderung δ_rad eines Rades von einer dem Rad zugeordneten Referenzaufbauhöhe z_ref des Fahrzeugs und mindestens einer Höhenstandssensorhöhe Z_FL, Z_FR, Z_RL, Z_RR. Im Anschluss können je nach Auftreten einer Nickbewegung oder eine Wankbewegung bzw. je nach Stärke dieser Bewegungen die folgenden Verfahrensschritte durchgeführt werden:
  • C1) Ermitteln einer Längsbeschleunigung a_x des Fahrzeugs;
  • C2) Ermitteln eines Nickwinkels θ_y;
  • C3) Ermitteln einer Nickwinkelgeschwindigkeit θ_y/t;
  • C4) Ermitteln einer Nickwinkelbeschleunigung θ_y/t²; (und/)oder
  • D1) Ermitteln einer Querbeschleunigung a_y des Fahrzeugs;
  • D2) Ermitteln eines Wankwinkels θ_x
  • D3) Ermitteln einer Wankwinkelgeschwindigkeit θ_x/t
  • D4) Ermitteln einer Wankwinkelbeschleunigung θ_x/t²; und
• E) Berechnen einer Schwerpunktshöhe h_sp unter Verwendung der ermittelten Parameter A, B, C1, C2, C3, C4 und/oder A, B, D1, D2, D3, D4.

The 1 shows a block diagram illustrating the sequence of the following method steps:

• A) Determining a reference _installation height z _{ref of} the vehicle and at least one height sensor height Z _FL , Z _FR , Z _RL , Z _RR . In this method step, the height sensor height Z _FL , Z _FR , Z _RL , Z _{RR can be determined} by (at least) one wheel or by (at least) one axis. For example, the reference pitch can be determined with a distance sensor (directed to the roadway).
• B) determining a body height change δ _{rad of} a wheel from a wheel assigned to the reference reference height z _{ref of} the vehicle and at least one height sensor height Z _FL , Z _FR , Z _RL , Z _RR . Depending on the occurrence of a pitching motion or a rolling movement or depending on the strength of these movements, the following method steps can subsequently be carried out:
  • C1 ) Determining a longitudinal acceleration a _{x of} the vehicle;
  • C2 ) Determining a pitch angle θ _y ;
  • C3 ) Determining a pitch angular velocity θ _y / t;
  • C4 ) Determining a pitch angular acceleration θ _y / t ² ; (and or
  • D1 ) Determining a lateral acceleration a _{y of} the vehicle;
  • D2 ) Determining a roll angle θ _x
  • D3 ) Determining a roll angular velocity θ _x / t
  • D4 ) Determining a roll angular acceleration θ _x / t ² ; and
• E) Calculate a center of gravity height h _sp using the determined parameters A . B . C1 . C2 . C3 . C4 and or A . B . D1 . D2 . D3 . D4 ,

für die Längsrichtung mit C1, C2, C3, C4;
(und/)oder $$\frac{K_{ef{f}_{rad}}{b}_{fzg}}{m_{Fzg}}{\delta }_{rad}=a_y{h}_{sp}+fehler\left(\frac{\mathrm{\theta }\text{x}}{t^2},\frac{\mathrm{\theta }\text{x}}{\text{t}},\mathrm{\theta }\text{x}\text{,}{\dot{h}}_{sp}\right)$$

für die Querrichtung mit D1, D2, D3, D4;
wobei

• K_{eff rad} = Effektiv Federrate für die jeweilige Feder [N/m]
• L_fzg = Radstand [m]
• m_Fzg = Fahrzeugmasse [Kg] ist
• b_fzg = Fahrzeugspurweite [m]
• a_x = Fahrzeuglängsbeschleunigungssensorwert [ms^-2]
• a_y = Fahrzeugquerbeschleunigungssensorwert [ms^-2].

In the process step e becomes the center of gravity h _sp calculated using the following equations (inertial coordinate system): $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{y}}{{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="DE102017131160A1\_0022.png"\; state="\{\{state\}\}">t</figure-callout>}}^2}.\frac{\mathrm{\theta }\text{y}}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right)$$

for the longitudinal direction with C1 . C2 . C3 . C4 ;
(and or $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_y{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{<figure-callout id="2" label="x t" filenames="DE102017131160A1\_0022.png" state="{{state}}">x </figure-callout>}}{t^{}}.\frac{\mathrm{\theta }\text{x}}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

for the transverse direction with D1 . D2 . D3 . D4 ;
in which

• K _{eff wheel} = Effective spring rate for each spring [N / m]
• L _fzg = wheelbase [m]
• m _Fzg = vehicle mass [Kg]
• b _fzg = vehicle _gauge [m]
• a _x = vehicle longitudinal acceleration sensor ^value [ms ^-2 ]
• a _y = vehicle lateral ^acceleration sensor ^value [ms ^-2 ].

The selection of the calculation method takes place taking into account the error term, which in turn takes into account the driving situation. So can on winding roads D1 .1 can be preferred and on straight stretches C1.1 be more specific.

Furthermore, the method in the box with the dashed lines as optionally characterized additionally comprises the method step F1 ) Determining a vehicle longitudinal speed V _x and / or vehicle longitudinal acceleration v̇ _x , wherein the center of gravity h _sp is calculated using the following equation (non-inertial coordinate system) $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}={\dot{v}}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{y}}{{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="DE102017131160A1\_0022.png"\; state="\{\{state\}\}">t</figure-callout>}}^2}.\frac{\mathrm{\theta }\text{y}}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right)$$

Alternatively (or additively), the method may further include the method step F2 ) Determining a vehicle lateral velocity V _y and / or vehicle lateral acceleration v̇ _y (non-inertial coordinate system) include.

All process steps shown in the dashed box are optional and in the order not necessarily execute as shown. Thus, optionally, the method may include the method step G) determining a vehicle vertical acceleration a _z include.

The method further comprises the method step H1 ) Determining a yaw rate ω _z and H2 ) Determining a centrifugal acceleration ω _Z v _x, where the center of gravity h _sp calculated using the following equation (non-inertial coordinate system): $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}={\omega }_z{v}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{<figure-callout id="2" label="x t" filenames="DE102017131160A1\_0022.png" state="{{state}}">x </figure-callout>}}{t^{}}.\frac{\mathrm{\theta }\text{x}}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

This calculation method can be performed on the basis of the adjustment, in particular the size (absolute value) of the error term.

Optionally, the method further comprises the method step I) determining a damper energization VL . VR . HL . MR to correct the error.

Optionally, the method further comprises the method step J) determining a door status T.

Optionally, the method further comprises the method step K) determining a road surface unevenness F.

Optionally, the method further comprises method step L) testing the error term of equations C1.1, C1.2 and D1.1 and D1.2 and either using the equation with the lower absolute value in the error term or following from that equation vehicle center or a predetermined driving situation criterion.

In 2 is a vehicle 1 represented with a roof rack. The vehicle 1 includes control unit 2 , several with the control unit 2 connected sensors 3 (for example, only one is drawn) for determining a vehicle parameter.

• Starten des Steuergeräts 2 und initiales Ermitteln, ob eine Schwerpunktshöhe h_sp gespeichert vorliegt;
• Danach erfolgt die Entscheidung, ob
  1. a) Gewichtsbestimmung;
  2. b) Federratenbestimmung
  3. c) Gewichtsbestimmung und Federratenbestimmung
  vorliegt und für den Fall:
  • JA: erfolgt eine Berechnung verschiedener Parameter, wie „Masse“ und „Federrate“
  • Bei: a) $$m_{Fzg}^{k+1}=m_{Fzg}^k+\mathrm{\Delta }{m}_{Fzg}$$
    
  • Bei: b) $$K_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
    
  • Bei: c) $$m_{Fzg}^{k+1}=m_{Fzg}^k+\mathrm{\Delta }{m}_{Fzg}\text{\&\& }{K}_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
    
  für den Fall Nein: erfolgt die Berechnung der Schwerpunktshöhe h_sp wie im Zusammenhang mit 1 beschrieben.

It is explicitly based on the procedure associated with 1 is described, reference is made. This procedure can be performed on the controller as follows:

• Start the controller 2 and initially determining if a center of gravity height h _sp stored exists;
• After that, the decision is made whether
  1. a) weight determination;
  2. b) Spring rate determination
  3. c) Weight determination and spring rate determination
  exists and in case:
  • YES: a calculation of various parameters, such as "mass" and "spring rate"
  • At a) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}$$
    
  • In case of: b) $$K_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
    
  • At: c) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}\text{\&\&}{K}_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$
    
  in the case no: the calculation of the center of gravity height h _sp takes place as in connection with 1 described.

Optionally, the method includes that the center of gravity height h _sp is compared with a standard value for the center of gravity height h ₀ .

Optionally, the method includes that the center of gravity height h _sp is compared with a previously stored center of gravity height h ₀ to determine an increase or decrease of the center of gravity height Δh _sp .

Optionally, the method comprises at least one vehicle dynamics control system ABS / ESP / Quattro-Sport / EFP on the basis of the ascertained center of gravity height h _sp is set.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006002973 A1 [0003]
• DE 10247993 B4 [0004]

Claims (14)

Method for determining a center of gravity height h _{sp of} a motor vehicle, comprising the following method steps: A) determining a reference body height z _{ref of} the vehicle and at least one height sensor height Z _FL , Z _FR , Z _RL , Z _RR ; B) determining a body height change δ _{rad of} a wheel from a reference elevation height z _{ref of} the vehicle associated with the wheel and at least one altitude sensor elevation Z _FL , Z _FR , Z _RL , Z _RR ; C1) determining a longitudinal acceleration a _{x of} the vehicle; C2) determining a pitch angle θ _y ; C3) determining a pitch angular velocity θ _y / t; C4) determining a pitch angular acceleration θ _y / t ² ; and / or D1) determining a lateral acceleration a _{y of} the vehicle; D2) determining a roll angle θ _x D3) determining a roll angular velocity θ _x / t D4) determining a roll angular acceleration θ _x / t ² ; and E) calculating a centroid height hsp using the determined parameters A, B, C1, C2, C3, C4 and / or A, B, D1, D2, D3, D4. Method according to Claim 1 , where the center of gravity height _{hsp is} calculated using the following equations: $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{y}}{t^2}.\frac{\mathrm{\theta }\text{y}}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right)$$

for the longitudinal direction with C1, C2, C3, C4; and or $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}=a_y{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{x}}{t^2}.\frac{\mathrm{\theta }\text{x}}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

for the transverse direction with D1, D2, D3, D4; where K _{eff wheel} = Effective spring rate for the respective spring [N / m] L _fzg = Wheelbase [m] m _Fzg = Vehicle mass [Kg] b _fzg = Vehicle _gauge [m] a _x = Vehicle _{longitudinal acceleration sensor value} [ms ^-2 ] a _y = Vehicle _{lateral acceleration sensor value} [ms ^-2 ] is. Method according to Claim 1 or 2 , further comprising the method step F1) determining a vehicle longitudinal speed V _x and / or vehicle longitudinal acceleration v̇ _x , wherein the center of gravity height h _{sp is} calculated using the following equation: $$\frac{K_{ef{f}_{rad}}{L}_{fzG}}{m_{FzG}}{\delta }_{rad}={\dot{v}}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{y}}{t^2}.\frac{\mathrm{\theta }\text{y}}{\text{t}}.\mathrm{\theta }\text{y}\text{.}{\dot{H}}_{sp}\right)$$

Method according to Claim 1 or 2 , further comprising the method step F2) determining a vehicle lateral velocity V _y and / or vehicle lateral acceleration v̇ _y . Method according to one of the preceding claims, further comprising the method step G) determining a vehicle vertical acceleration a _z . Method according to one of the preceding claims, further comprising the method step H1) determining a yaw rate ω _z , and H2) determining a centrifugal acceleration ω _Z v _x , wherein the center of gravity height hsp is calculated using the following equation: $$\frac{K_{ef{f}_{rad}}{b}_{fzG}}{m_{FzG}}{\delta }_{rad}={\omega }_z{v}_x{H}_{sp}+feHler\left(\frac{\mathrm{\theta }\text{x}}{t^2}.\frac{\mathrm{\theta }\text{x}}{\text{t}}.\mathrm{\theta }\text{x}\text{.}{\dot{H}}_{sp}\right)$$

Method according to one of the preceding claims, further comprising the method step I) determining a damper current VL, VR, HL, HR. Method according to one of the preceding claims, further comprising the method step J) determining a door status T. Method according to one of the preceding claims, further comprising the method step K) determining a road surface unevenness F. Method according to one of the preceding claims, further comprising the step L) either checking the error term of the equations C1.1, C1.2, D1.1 and D1.2 and using the equation with the lower absolute value in the error term or in a predetermined driving situation. Method according to one of the preceding claims, further comprising the method steps: 1. providing a control device (2) in the vehicle (1); 2. providing at least one sensor (3) connected to the control unit (2) for determining a vehicle parameter according to one of the preceding claims; 3. starting the control unit (2) and initially determining whether a center of gravity height h _{sp is} stored; 4. Decision whether 4a) weight determination; 4b) spring rate determination; 4c) weight determination and spring rate determination is present and in the case: YES: a calculation of various parameters, such as "mass" and "spring rate" takes place in the case of: 4a) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}$$

At: 4b) $$K_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$

At 4c) $$m_{FzG}^{k+1}=m_{FzG}^k+\mathrm{\Delta }{m}_{FzG}\text{\&\&}{K}_{ef{f}_{rad}}^{k+1}=K_{ef{f}_{rad}}^k+\mathrm{\Delta }{K}_{ef{f}_{rad}}$$

for the case no: the calculation of the center of gravity height h _sp according to one of the preceding claims. Method according to one of the preceding claims, wherein the center of gravity height h _{sp is} compared with a standard value for the center of gravity height h ₀ . Method according to one of the preceding claims, wherein the center of gravity height h _{sp is} compared with a previously stored center of gravity height h to determine an increase or decrease of the center of gravity height Δh _sp . Method according to one of the preceding claims, wherein at least one vehicle-dynamics control system ABS / ESP / Quattro-Sport / EFP is set on the basis of the ascertained center of gravity height _hsp .

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