DE102022201560A1 - Method for determining a rigidity of a chassis - Google Patents

Abstract

Method for determining the rigidity of a chassis (2) of a vehicle (1) which, in addition to the chassis (2), has a vehicle drive (5) and a vehicle body (3), the vehicle drive (5) acting on the vehicle (1) a driving force (F) is exerted, by means of which the vehicle (1) is accelerated, at least one force signal (Sf) characterizing the driving force (F) is determined by measurement, at least one of the acceleration of the vehicle (1 ) characterizing acceleration signal (Sa) is determined by measurement, from the acceleration signal (Sa) and the force signal (Sf) a mass signal (Smd) characterizing the current mass of the vehicle (1) is generated, when the vehicle (1) is at least one the height (h) of the vehicle (1) characterizing height signal (Sh) is determined by measurement and from the height signal (Sh) and the mass signal (Smd) at least one current stiffness of the chassis (2) characterizing value (c) is formed.

Description

The invention relates to a method for determining a rigidity of a chassis of a vehicle and a vehicle with a device for determining a rigidity of a chassis of the vehicle.

If the mass of a vehicle body is increased by loading, the vehicle deflects further than when it is empty. A level sensor can thus be used to make a statement about the loading of a vehicle. However, wear and tear or a reduction in the rigidity of the chassis (rubber bearings, spring constant) increases the deflection of the vehicle over time with the same load.

Proceeding from this, the object of the invention is in particular to be able to determine a current value for the rigidity of the chassis.

According to the invention, this object is achieved with a method according to claim 1 . Preferred developments of the invention are given in the dependent claims and in the following description.

• - mittels des Fahrzeugantriebs auf das Fahrzeug eine Antriebskraft ausgeübt wird, mittels welcher das Fahrzeug beschleunigt wird,
• - wenigstens ein die Antriebskraft charakterisierendes Kraftsignal durch Messung ermittelt wird,
• - wenigstens ein die durch die Antriebskraft bewirkte Beschleunigung des Fahrzeugs charakterisierendes Beschleunigungssignal durch Messung ermittelt wird,
• - aus dem Beschleunigungssignal und dem Kraftsignal ein die aktuelle Masse des Fahrzeugs charakterisierendes Massesignal erzeugt wird,
• - in einem, insbesondere nachfolgenden, Stillstand des Fahrzeugs wenigstens ein den Höhenstand des Fahrzeugs charakterisierendes Höhenstandsignal durch Messung ermittelt wird und
• - aus dem Höhenstandsignal und dem Massesignal wenigstens ein eine aktuelle Steifigkeit des Fahrwerks charakterisierender Wert gebildet wird.

According to the invention, a method for determining a rigidity of a chassis of a vehicle is created which, in addition to the chassis, has a vehicle drive and a vehicle body, wherein

• - a driving force is exerted on the vehicle by means of the vehicle drive, by means of which the vehicle is accelerated,
• - at least one force signal characterizing the driving force is determined by measurement,
• - at least one acceleration signal characterizing the acceleration of the vehicle caused by the driving force is determined by measurement,
• - a mass signal characterizing the current mass of the vehicle is generated from the acceleration signal and the force signal,
• - When the vehicle is at a standstill, in particular a subsequent standstill, at least one ride height signal characterizing the ride height of the vehicle is determined by measurement and
• - At least one value characterizing a current rigidity of the chassis is formed from the level signal and the mass signal.

The method according to the invention is suitable for being able to repeatedly form values that characterize the current rigidity of the chassis during the service life of the vehicle.

Preferably, the aforementioned, in particular subsequent, standstill of the vehicle occurs after the vehicle has accelerated and/or after the mass signal has been generated and/or without a change in the mass and/or the load of the vehicle. The at least one value characterizing the current stiffness of the chassis is or includes a value tuple, for example. For example, this tuple is one or at least one 1-tuple, a 2-tuple or a 3-tuple. The chassis carries in particular the vehicle body and/or the vehicle drive. The expression "at least one" includes in particular the meaning of "one" or "exactly one". The same applies to the expression “at least one”.

The vehicle and/or the chassis preferably includes a plurality of, in particular four, vehicle wheels. The vehicle and/or the running gear preferably comprises a plurality of, in particular two, vehicle axles. Each vehicle axle advantageously includes two vehicle wheels or two of the vehicle wheels. The vehicle and/or the chassis preferably includes an axle suspension for each vehicle axle and/or a wheel suspension for each vehicle wheel. The axle suspensions and/or the wheel suspensions preferably comprise wheel carriers and/or chassis links and/or joints and/or vehicle springs and/or dampers and/or stabilizers and/or tie rods. One of the wheel carriers is preferably assigned to each vehicle wheel. The vehicle has in particular a vehicle transmission, which is preferably connected to the vehicle drive. The chassis advantageously carries the vehicle transmission.

A base is preferably provided on which the vehicle, in particular with its chassis and/or with its vehicle wheels, stands and/or drives. The subsoil is e.g. a roadway or street. In particular, the subsoil is inclined or flat. An example of an inclined surface is e.g. a decline or a slope or an incline or a mountain.

A vehicle longitudinal direction and/or a vehicle transverse direction and/or a vehicle vertical direction is preferably assigned to the vehicle. The vertical direction of the vehicle preferably runs transversely to the longitudinal direction of the vehicle. The transverse direction of the vehicle advantageously runs transversely to the longitudinal direction of the vehicle and transversely to the vertical direction of the vehicle. The vehicle axles are arranged at a distance from one another, in particular in the longitudinal direction of the vehicle. The vehicle wheels of each vehicle axle are advantageous haft arranged in the vehicle transverse direction at a distance from each other. The vehicle is preferably assigned a vehicle longitudinal axis and/or a vehicle transverse axis and/or a vehicle vertical axis. The vehicle longitudinal axis and the vehicle vertical axis preferably run through a vehicle center of the vehicle. Advantageously, the transverse axis of the vehicle runs through the wheel centers of the vehicle wheels of one, for example the front, of the vehicle axles. The longitudinal axis of the vehicle preferably runs in the longitudinal direction of the vehicle. The vertical axis of the vehicle preferably runs in the vertical direction of the vehicle. The vehicle transverse axis advantageously runs in the vehicle transverse direction.

In an unloaded state, the vehicle has, in particular, an unladen mass. The unladen mass or mass of the vehicle is preferably known and/or specified. The mass of the vehicle, in particular when it is loaded, preferably corresponds to the sum of the unladen mass of the vehicle and the mass of the or a load of the vehicle. The or a load on the vehicle is also referred to as a load, for example.

The mass of the vehicle preferably corresponds to the sum of an unsprung vehicle mass and a sprung vehicle mass. The sprung vehicle mass preferably includes the mass of the vehicle body and/or the mass of the vehicle drive and/or the mass of the vehicle transmission or transmission and/or the mass of the vehicle load or loads. Advantageously, the sprung vehicle mass also includes part of the mass of each wheel suspension and/or each axle suspension. The sprung vehicle mass is dependent in particular on the loading or loading of the vehicle. The sprung vehicle mass of the unloaded vehicle is advantageously known and/or specified. The unsprung vehicle mass preferably includes the mass of the vehicle wheels. Advantageously, the unsprung vehicle mass also includes one, in particular another, part of the mass of each wheel suspension and/or each axle suspension. The unsprung vehicle mass is, in particular, independent of the loading or loading of the vehicle. The unsprung mass of the vehicle is advantageously known and/or predetermined.

The sprung vehicle mass is preferably supported, in particular resiliently, on the unsprung vehicle mass, preferably in such a way that the spring stiffness of this resilient support corresponds or at least approximately corresponds to the stiffness of the chassis. For example, the unsprung vehicle mass can be taken into account when determining the value that characterizes the current stiffness of the chassis.

The vehicle preferably has a drive train, which preferably includes the vehicle drive and/or the vehicle transmission. In order to determine the force signal that characterizes the driving force, a torque and/or a speed in the drive train of the vehicle are measured in particular. For example, to determine the force signal characterizing the driving force, a torque and/or a speed of the vehicle drive is measured. In addition or as an alternative, a torque and/or a speed of the vehicle transmission, for example, is measured to determine the force signal that characterizes the driving force. In addition or as an alternative, a shift state and/or a transmission ratio of the vehicle transmission, for example, is recorded in order to determine the force signal that characterizes the driving force. In addition or as an alternative, a speed of the vehicle, for example, is recorded in order to determine the force signal that characterizes the driving force. The or each torque is determined, for example, by means of at least one torque sensor. The or each speed is determined, for example, by means of at least one speed sensor. The shifting state and/or the transmission ratio of the vehicle transmission is determined, for example, by means of a shifting state sensor and/or by means of a transmission control unit. The speed of the vehicle is determined, for example, using a speed sensor. The force signal characterizing the driving force is preferably determined, in particular at least, by means of at least one torque sensor and/or by means of at least one speed sensor, for example on the vehicle drive and/or on the vehicle transmission and/or in the drive train of the vehicle.

The force signal characterizing the driving force is preferably determined by means of a driving force detection unit. The driving force detection unit comprises, for example, at least one torque sensor and/or at least one rotational speed sensor and/or shift state sensor and/or speed sensor.

The acceleration signal characterizing the acceleration of the vehicle is preferably determined by means of at least one acceleration sensor. The at least one acceleration sensor is provided in the chassis, for example. The at least one acceleration sensor is preferably arranged in the center of gravity of the vehicle.

The vehicle preferably has a dynamic weighing unit. Preferably, by means of the dynamic weighing unit from the acceleration signal and the force signal, the current Mass of the vehicle characterizing mass signal generated. The generation of the mass signal characterizing the current mass of the vehicle is based, for example, on Newton's second law, according to which the force accelerating a mass results from the product of acceleration and mass.

The ride height signal characterizing the ride height of the vehicle and/or the vehicle body is determined in particular by at least one ride height sensor. The ride height is preferably measured and/or determined as a deviation of a height of a defined location of the vehicle body from a reference height of this location, which results, for example, in a design position of the unladen vehicle. In particular, a position in the vertical direction of the vehicle, preferably in relation to the ground and/or the chassis, is referred to as an altitude.

The vehicle preferably has an evaluation unit. In particular, the evaluation unit is connected to the dynamic weighing unit. The at least one value characterizing the current rigidity of the chassis is preferably formed by means of the evaluation unit. The at least one value that characterizes the current stiffness of the chassis is referred to, for example, as the current stiffness value or as the current stiffness value tuple. For example, the at least one value that characterizes the current rigidity of the chassis can be determined on the basis of Hooke's law. Additionally or alternatively, a table is stored and/or stored, for example, in which one or more stiffness values or stiffness value tuples are or will be stored and/or stored and/or one or more ride height values are or will be related to one or more mass values .

The vehicle preferably has a memory unit. The evaluation unit is preferably connected to the memory unit. In particular, the evaluation unit has access to the storage unit. The value characterizing the current rigidity of the chassis is preferably stored and/or stored in the memory unit. For example, the table is stored and/or stored in the memory unit.

The vehicle preferably has a stationary weighing unit. The stationary weighing unit is preferably connected to the storage unit. In particular, the stationary weighing unit has access to the memory unit. For example, the storage unit can be assigned to the stationary weighing unit.

According to one embodiment, another mass signal characterizing the current mass of the vehicle is generated, in particular by means of the stationary weighing unit, from the ride height signal and from at least one stored value characterizing a stiffness of the chassis. The stored value characterizing the stiffness of the chassis is preferably updated and/or replaced with or by the value characterizing the current stiffness of the chassis, in particular before the generation of the other mass signal. The at least one stored value characterizing the rigidity of the chassis is and/or is stored and/or stored in particular in the storage unit.

According to one embodiment, at least one position signal characterizing the current position of the chassis and/or the vehicle, in particular relative to the center of the earth, is determined by measurement, preferably by means of at least one inertial sensor. For example, the position signal is taken into account when generating the other ground signal. The at least one inertial sensor is preferably connected to the stationary weighing unit. The at least one inertial sensor is implemented, for example, in the form of a microsystem (MEMS).

The current position of the chassis and/or the vehicle in relation to the center of the earth provides information, for example, as to whether the ground on which the vehicle is standing and/or driving is inclined or flat. The influence of an inclined subsoil can thus be eliminated when generating the other mass signal.

Furthermore, the acceleration signal characterizing the acceleration of the vehicle can be determined by means of the at least one inertial sensor. An additional and/or separate acceleration sensor for determining the acceleration signal can thus be omitted. The inertial sensor preferably comprises a plurality of acceleration sensors, three of which in particular are aligned perpendicular to one another.

According to one development, a local ride height signal characterizing a local ride height of the vehicle and/or the vehicle body is determined and/or measured at at least three, preferably four, different locations of the vehicle, preferably using a plurality of local ride height sensors. In particular, a center of gravity signal characterizing a current center of gravity of the vehicle and/or the vehicle body is generated from the local level signals, preferably by means of the stationary weighing unit or a center of gravity determination unit. The position signal is used, for example, when generating the center of gravity signal taken into account. The number of local ride height sensors is advantageously at least three or four. The at least one ride height sensor includes in particular the local ride height sensors. The stationary weighing unit forms, for example, the or a center of gravity determination unit.

The vehicle preferably has a display unit which is connected in particular to the stationary weighing unit and/or the center of gravity determination unit. The current center of gravity of the vehicle is advantageously visualized, preferably by means of the or a display unit.

According to a further development, a current mass of the load of the vehicle is determined, taking into account the or a predefined empty mass of the vehicle, in particular by means of the dynamic weighing unit and/or by means of the stationary weighing unit.

According to a development, a state value characterizing wear of the chassis is formed or determined from or from the current value.

A value characterizing the current rigidity of the chassis is preferably formed by the invention by means of a dynamic determination of the vehicle mass and a measurement of the ride height when the vehicle is stationary. This value is used in particular to update a stored value that characterizes the rigidity of the chassis and is used when the vehicle mass is determined in a stationary manner. A stationary determination of the vehicle mass offers the advantage that the vehicle mass can be determined at a standstill, i.e. before the start of a journey.

The dynamic determination of the vehicle mass takes place in particular by means of the dynamic weighing unit. The stationary determination of the vehicle mass takes place in particular by means of the stationary weighing unit.

• - mittels des Fahrzeugantriebs auf das Fahrzeug eine Antriebskraft ausübbar ist, mittels welcher das Fahrzeug beschleunigbar ist,
• - wenigstens ein die Antriebskraft charakterisierendes Kraftsignal durch eine Antriebskraft-Erfassungseinheit ermittelbar ist,
• - wenigstens ein die durch die Antriebskraft bewirkte Beschleunigung des Fahrzeugs charakterisierendes Beschleunigungssignal durch wenigstens einen Beschleunigungssensors ermittelbar ist,
• - mittels einer dynamischen Wiegeeinheit aus dem Beschleunigungssignal und dem Kraftsignal ein die aktuelle Masse des Fahrzeugs charakterisierendes Massesignal erzeugbar ist,
• - in einem, insbesondere nachfolgenden, Stillstand des Fahrzeugs wenigstens ein den Höhenstand des Fahrzeugs charakterisierendes Höhenstandsignal durch wenigstens einen Höhenstandsensors ermittelbar ist und
• - mittels einer Auswerteeinheit aus dem Höhenstandsignal und dem Massesignal wenigstens ein die aktuelle Steifigkeit des Fahrwerks charakterisierender Wert bildbar ist.

The invention also relates in particular to a vehicle with a chassis, a vehicle drive and a vehicle body, wherein

• - a driving force can be exerted on the vehicle by means of the vehicle drive, by means of which the vehicle can be accelerated,
• - at least one force signal characterizing the driving force can be determined by a driving force detection unit,
• - at least one acceleration signal characterizing the acceleration of the vehicle caused by the driving force can be determined by at least one acceleration sensor,
• - a mass signal characterizing the current mass of the vehicle can be generated by means of a dynamic weighing unit from the acceleration signal and the force signal,
• - When the vehicle is at a standstill, in particular a subsequent standstill, at least one ride height signal characterizing the ride height of the vehicle can be determined by at least one ride height sensor and
• - At least one value characterizing the current rigidity of the chassis can be formed by means of an evaluation unit from the ride height signal and the mass signal.

The vehicle according to the invention is intended in particular for carrying out the method according to the invention. Preferably, the method according to the invention can be carried out or is carried out with the vehicle according to the invention. The vehicle mentioned in connection with the method is preferably the vehicle according to the invention. The vehicle is in particular a motor vehicle.

The vehicle according to the invention can be further developed according to all of the configurations explained in connection with the method according to the invention. Furthermore, the method according to the invention can be further developed according to all the configurations explained in connection with the vehicle according to the invention. Expressions of activity used in connection with the method, such as "produce", can be distinguished in particular by their associated derivatives with the suffix "bar", such as e.g. B. "generable" or by corresponding expressions.

According to one embodiment, another mass signal characterizing the current mass of the vehicle can be generated by means of a stationary weighing unit from the ride height signal and from at least one value characterizing a stiffness of the chassis and stored in a storage unit. Preferably, the value characterizing the rigidity of the chassis and stored in the storage unit can be updated and/or replaced with or by the value characterizing the current rigidity of the chassis, in particular before the generation of the other mass signal.

According to a development, at least one position signal characterizing the current position of the chassis relative to the center of the earth can be determined by at least one inertial sensor. The position signal can preferably be taken into account when generating the other ground signal.

According to one embodiment, a local ride height signal characterizing a local ride height of the vehicle can be measured by means of local ride height sensors at at least three different locations on the vehicle. A center of gravity signal characterizing a current center of gravity of the vehicle can preferably be generated from the local level signals by means of the stationary weighing unit. The at least one ride height sensor includes in particular the local ride height sensors.

The position signal can preferably be taken into account when generating the center of gravity signal. The current center of gravity of the vehicle can advantageously be visualized using a display unit.

The vehicle preferably has a device which is in particular a device for determining a rigidity of the chassis or chassis of the vehicle. The device preferably comprises the dynamic weighing unit and/or the evaluation unit and/or the stationary weighing unit. The device is referred to in particular as a weighing device.

• 1 eine schematische Ansicht eines Fahrzeugs,
• 2 eine schematische Ansicht einer Wiegevorrichtung zur Durchführung des erfindungsgemäßen Verfahrens gemäß einer Ausführungsform und
• 3 eine optionale Weiterbildung einer stationären Wiegeeinheit der Wiegevorrichtung.

The invention is described below using a preferred embodiment with reference to the drawing. Show in the drawing:

• 1 a schematic view of a vehicle,
• 2 a schematic view of a weighing device for carrying out the method according to the invention according to one embodiment and
• 3 an optional development of a stationary weighing unit of the weighing device.

Out of 1 a vehicle 1 can be seen, which has a chassis 2 and a vehicle body 3 carried by the chassis 2 and loaded with a load 4, which is also referred to as a load. Furthermore, the vehicle 1 has a vehicle drive 5 and optionally a vehicle transmission 6 . The chassis 2 includes vehicle wheels 7, by means of which the vehicle 1 stands up on a base 8. The number of vehicle wheels 7 is four, in particular. The vehicle drive 5, the optional vehicle transmission 6 and preferably also the vehicle wheels 7 are part of a drive train 9 of the vehicle 1. The vehicle drive 5 can be used to move the vehicle 1 in a direction of travel 10, which here corresponds in particular to a normal forward direction of travel of the vehicle 1.

1 also shows a vehicle longitudinal direction x and a vehicle vertical direction z, with the direction of travel 10 running in the vehicle longitudinal direction x. A height h of the vehicle 1 running in the vertical direction z of the vehicle is also shown, which results, for example, from a deviation of a current height z1 of a defined location of the vehicle body 3 from a reference height z0 of this location.

Out of 2 a weighing device 11 of the vehicle 1 can be seen, which has a dynamic weighing unit 12, a stationary weighing unit 13, an evaluation unit 14 and a memory unit 15, which is connected both to the evaluation unit 14 and to the stationary weighing unit 13. The storage unit 15 can in particular be assigned to the stationary weighing unit 13 .

The vehicle 1 is accelerated by the vehicle drive 5 in the direction of travel 10 , with an acceleration signal Sa characterizing this acceleration being determined by means of an acceleration sensor 16 and fed to the dynamic weighing unit 12 . The acceleration of the vehicle 1 can be assigned a driving force F which acts on the vehicle 1 and which is to be applied by the vehicle drive 5 . At least one force signal Sf characterizing this driving force F is determined by measurement, preferably by means of a driving force detection unit 22 , and fed to the dynamic weighing unit 12 .

To determine the at least one force signal Sf, in particular at least one torque in the drive train 9 is determined by means of at least one torque sensor 17 which generates a torque signal St characterizing the torque and feeds it to the dynamic weighing unit 12 . The force signal Sf includes, for example, the torque signal St. In particular, the torque signal St forms the force signal Sf. In addition, for example, at least one speed in the drive train 9 is determined by means of at least one speed sensor 18, which generates a speed signal Sr characterizing the speed and feeds it to the dynamic weighing unit 12. For example, the at least one force signal Sf includes the torque signal St and the speed signal Sr. The at least one torque is or includes, for example, a torque of the vehicle drive 5 and/or a torque of the vehicle transmission 6. The at least one speed is or includes, for example, a speed of the vehicle drive 5 and/or a speed of the vehicle transmission 6. The driving force detection unit 22 thus preferably comprises the torque sensor 17 and/or the speed sensor 18.

A mass signal Smd characterizing the current mass of the vehicle 1 is now generated from the force signal Sf and the acceleration signal Sa by means of the dynamic weighing unit 12 and fed to the evaluation unit 14 .

When vehicle 1 comes to a standstill, in particular subsequently, e.g. at a red traffic light or when parking, at least one ride height signal Sh characterizing the current ride height h of the vehicle is determined by measurement using at least one ride height sensor 19 and fed to evaluation unit 14.

From the mass signal Sm and the ride height signal Sh, the evaluation unit 14 forms at least one value {c} characterizing the current rigidity of the running gear 2 and stores this value in the memory unit 15 as a value {cs}. A value {cs} previously stored in the memory unit 15 for the current height h is updated and/or replaced in particular with and/or by the value {c}.

To determine the current mass of the vehicle 1 by means of the stationary weighing unit 13 when the vehicle 1 is stationary, the height signal Sh characterizing the current height h of the vehicle 1 is fed to the stationary weighing unit 13, which from the memory unit 19 at least one characterizes the rigidity of the chassis 2, reads out the stored value {cs} that matches the current altitude h. The stored value {cs} is read out in particular after the aforementioned update. This value {cs} is therefore preferably the value previously updated with the value {c}, in particular if the loading of the vehicle 1 has not changed since the update and/or the formation of the value {c}. Using the stationary weighing unit 13, another mass signal Sms characterizing the current mass of the vehicle 1 is now generated and output on the basis of the at least one stored value {cs}.

Optionally, at least one position signal So characterizing the current position of the chassis 2 relative to the center of the earth is determined by means of an inertial sensor 20 and taken into account when generating the mass signal Sms. It is thus possible to detect an inclination of the subsoil 8 and to calculate its influence when generating the other mass signal Sms characterizing the current mass. The inertial sensor 20 can also be used to determine the acceleration signal Sa, so that the acceleration sensor 16 can be omitted as a separate component.

The at least one ride height sensor 19 includes, in particular, four local ride height sensors 19a, 19b, 19c and 19d, by means of which a local ride height signal Sha, Shb, Shc and Shd characterizing a local ride height of the vehicle body 3 is measured at different locations on the vehicle 1. In this case, in particular one of the local level sensors 19a, 19b, 19c, 19d is provided in the area of each vehicle wheel 7.

A center of gravity signal Ssp characterizing a current center of gravity of the vehicle 1 and/or the vehicle body 3 is generated and output from the local ride height signals Sha, Shb, Shc and Shd by means of the stationary weighing unit 13 . An inclination of the ground 8 is detected by means of the inertial sensor 20 so that its influence is factored out when determining the center of gravity signal Ssp. The stationary weighing unit 13 thus in particular also forms a center of gravity determination unit. The center of gravity signal Ssp is preferably fed to a display unit 21, by means of which the current center of gravity of the vehicle is visualized.

Reference List

1

vehicle

2

landing gear

3

vehicle body

4

load / loading

5

vehicle propulsion

6

Vehicle transmission (optional)

7

vehicle wheel

8th

underground

9

powertrain

10

driving direction

11

weighing device

12

dynamic weighing unit

13

stationary weighing unit

14

evaluation unit

15

storage unit

16

accelerometer

17

torque sensor

18

speed sensor

19

level sensor

20

inertial sensor

21

display unit

22

driving force detection unit

H

altitude

sat

acceleration signal

sf

power signal

sh

altitude signal

smd

Mass signal (generated by the dynamic weighing unit)

SMS

other mass signal (generated by the stationary weighing unit)

So

position signal

sir

speed signal

st

torque signal

x

vehicle longitudinal direction

e.g

vehicle elevation

Claims (10)

Method for determining a rigidity of a chassis (2) of a vehicle (1), which in addition to the chassis (2) has a vehicle drive (5) and a vehicle body (3), wherein - a driving force (F) is exerted on the vehicle (1) by means of the vehicle drive (5), by means of which the vehicle (1) is accelerated, - at least one force signal (Sf) characterizing the driving force (F) is determined by measurement, - at least one acceleration signal (Sa) characterizing the acceleration of the vehicle (1) caused by the driving force (F) is determined by measurement, - A mass signal (Smd) characterizing the current mass of the vehicle (1) is generated from the acceleration signal (Sa) and the force signal (Sf), - When the vehicle (1) is stationary, at least one ride height signal (Sh) characterizing the ride height (h) of the vehicle (1) is determined by measurement and - At least one value (c) characterizing a current rigidity of the chassis (2) is formed from the ride height signal (Sh) and the mass signal (Smd). procedure after claim 1 , characterized in that another mass signal (Sms) characterizing the current mass of the vehicle (1) is generated from the ride height signal (Sh) and at least one stored value (cs) characterizing a stiffness of the chassis (2), the stiffness The stored value (cs) characterizing the running gear (2) is updated with the value (c) characterizing the current rigidity of the running gear (2). procedure after claim 1 or 2 , characterized in that at least one position signal (So) characterizing the current position of the running gear (2) relative to the center of the earth is determined by measurement and taken into account when generating the other ground signal (Sms). Method according to one of the preceding claims, characterized in that a local height signal characterizing a local height level of the vehicle is measured at at least three different locations of the vehicle, a center of gravity signal (Ssp) characterizing a current center of gravity of the vehicle (1) being derived from the local level signals. is produced. Procedure according to claims 3 and 4 , characterized in that the position signal is taken into account when generating the center of gravity signal. Vehicle with a chassis (2), a vehicle drive (5) and a vehicle body (3), wherein - a driving force (F) can be exerted on the vehicle (1) by means of the vehicle drive (5), by means of which the vehicle (1) can be accelerated, - at least one force signal (Sf) characterizing the driving force (F) can be determined by a driving force detection unit (22), - at least one acceleration signal (Sa) characterizing the acceleration of the vehicle (1) caused by the driving force (F) can be determined by at least one acceleration sensor (16), - a mass signal (Smd) characterizing the current mass of the vehicle (1) can be generated by means of a dynamic weighing unit (12) from the acceleration signal (Sa) and the force signal (Sf), - When the vehicle (1) is stationary, at least one ride height signal (Sh) characterizing the ride height (h) of the vehicle (1) can be determined by at least one ride height sensor (19) and - At least one value (c) characterizing a current rigidity of the running gear (2) can be formed by means of an evaluation unit from the ride height signal (Sh) and the mass signal (Smd). vehicle after claim 6 , characterized in that the current mass of the vehicle (1st ) characterizing another mass signal (Sms) can be generated, wherein the stiffness of the chassis (2) characterizing and the value (cs) stored in the memory unit (19) can be updated with the value (c) characterizing the current rigidity of the chassis (2). vehicle after claim 6 or 7 , characterized in that at least one position signal (So) characterizing the current position of the chassis (2) relative to the center of the earth can be determined by at least one inertial sensor (20) and can be taken into account when generating the other mass signal (Sms). vehicle after one of Claims 6 until 8th , characterized in that a local height signal (Sha, Shb, Shc) characterizing a local height of the vehicle can be measured by means of local height sensors (19a, 19b, 19c) at at least three different locations on the vehicle, with the stationary weighing unit (13) a center of gravity signal (Ssp) characterizing a current center of gravity of the vehicle (1) can be generated from the local level signals (Sha, Shb, Shc). vehicle after the claims 8 and 9 , characterized in that the position signal (So) can be taken into account when generating the center of gravity signal (Ssp).

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