Method and device for determining the dynamic tire circumference of a vehicle

Abstract

The invention relates to a method and a device for determining the dynamic tire circumference of a vehicle. The method comprises the following steps: receiving a first signal (S1) representing the yaw rate of the vehicle, a second signal (S2) representing the wheel speed of the wheel of the vehicle, a third signal (S3) representing the steering angle of the vehicle, and a fourth signal (S4) representing the dynamic wheel width of the vehicle; determining a first output signal (A1) of the first Kalman filter (K1) representing the dynamic tire circumference of the wheel by using the first signal (S1), the second signal (S2), the third signal (S3) and the fourth signal (S4) as input signals for the first Kalman filter (K1); and using the first output signal (A1) in a control device of the vehicle.

Description

Technical Field

[0001] The present invention relates to a method and a device for determining the dynamic tire circumference of a vehicle, and in particular to determining the dynamic tire circumference based on a Kalman filter. Background Art

[0002] Vehicles are known from the prior art, which have assistance systems for automatically and / or semi-automatically performing driving maneuvers. Such assistance systems may be, for example, parking assistance systems, which are configured to automatically and / or semi-automatically maneuver the vehicle into a parking space based on environmental sensors and suitable environment recognition algorithms. In order to calculate a parking trajectory suitable for the vehicle, in addition to information about the vehicle geometry, information about the tire circumference of the corresponding wheels of the vehicle and the wheelbase of the vehicle is also required. The use of predefined values ​​for the corresponding tire circumference and the corresponding wheelbase of the vehicle may be too inaccurate due to the dynamic influence on these two variables, so that parking processes and maneuvers different therefrom cannot be performed with the desired and / or required predefined accuracy based on this. For this reason, the following methods and devices are known from the prior art, which determine the respective current dynamic tire circumference, based on which subsequent driving maneuvers can be performed with correspondingly higher accuracy.

[0003] Furthermore, so-called Kalman filters are known from the prior art, which are able to estimate the state of a system based on measured variables and in particular on measured variables that are contaminated by noise.

[0004] DE 10 2016 103 632 A1 describes a parking aid that takes into account a changing tire radius and wheelbase. Here, the tire radius is estimated using a plurality of parameters, such as the wheel speed of the vehicle, GPS speed, steering angle and yaw rate.

[0005] DE 10 2013 021 826 A1 discloses a method for determining a steering angle of a motor vehicle by means of a driver assistance device, wherein the wheel base is taken into account in addition to the wheel circumference.

[0006] DE 10 2012 208 298 A1 describes a method for determining the tire circumference in conjunction with the use of the yaw angle and deriving therefrom a method for controlling a parking maneuver.

[0007] DE 10 2010 000 867 A1 relates to a method for ascertaining an updated wheel circumference, in which an initially assumed wheel circumference is corrected in a reactive manner using measured acceleration data.

[0008] DE 10 2012 000 213 A1 discloses a method for ascertaining the current wheel circumference of at least one wheel of a motor vehicle based on two vehicle positions determined by satellite navigation.

[0009] DE 10 2006 058 567 A1 describes a method for ascertaining an updated wheel circumference, in which method various data sources are used, including GPS data.

[0010] DE 10 2010 007 650 A1 discloses a method for ascertaining the current wheel circumference, in which a distance value from a distance measurement using a distance sensor and the number of wheel pulses are used as the basis. Summary of the invention

[0011] According to a first aspect of the present invention, a method for determining the dynamic tire circumference of a vehicle is provided. The vehicle may be, for example, a road wheel (eg, a motorcycle, a car, a transport aircraft, a truck, a coach) or a rail vehicle or an aircraft or a ship.

[0012] In a first step of the method according to the invention, a first signal representing the yaw rate of the vehicle, a second signal representing the wheel speed of the wheels of the vehicle, a third signal representing the steering angle of the vehicle, and a fourth signal representing the dynamic wheel width of the vehicle are received by the device according to the invention in the vehicle. The dynamic tire circumference and the dynamic wheel width are advantageously usable variables compared to the technical tire circumference and the technical wheel width, since the dynamic tire circumference and the dynamic wheel width represent the dynamic wheel width of the vehicle during driving operation. The actual values ​​for the tire circumference and the wheelbase in the vehicle are to be understood as predefined values, which can be measured, for example, when the vehicle is stationary and / or obtained from the technical specifications of the vehicle and / or the currently used tires. In contrast, the dynamic tire circumference and the dynamic wheelbase are to be understood as those values ​​that are present during the actual driving operation of the vehicle. These values ​​may differ from the predefined technical values, for example, due to tire slip, temperature-related and / or load-related pressure fluctuations in the wheels or pressure losses in the wheels or other influencing factors.

[0013] The device according to the invention may preferably include an evaluation unit having a data input and a data output. By means of the data input, the evaluation unit can be connected to a plurality of sensors and / or control devices of the vehicle, for example via the vehicle network, which can detect and / or provide the above-mentioned signals. In addition, the evaluation unit can be connected to internal and / or external storage units in terms of information technology, in which data received and / or calculated by the evaluation unit can be stored.

[0014] The yaw rate (or also called yaw angular velocity) indicates the rotational speed of the vehicle around its vertical axis (z-axis) and can be detected, for example, by means of a rotation rate sensor of the vehicle. The wheel speed of the wheels of the vehicle can be detected by means of a wheel speed sensor, wherein preferably each of the wheels of the vehicle can have such a wheel speed sensor, so that the corresponding wheel speed of all wheels of the vehicle can be detected and taken into account. The steering angle of the vehicle can be detected, for example, based on a steering angle sensor, which is preferably arranged in or on the steering column of the vehicle and is configured to detect the corresponding turning angle of the steering wheel. The variables mentioned here, which are transmitted to the evaluation unit by means of a first signal, a second signal and a third signal, can be directly received by the corresponding sensors for detecting these variables and / or by a control device of the vehicle, which is connected to the corresponding sensors in terms of information technology.

[0015] In this case, the dynamic wheelbase can be a predefined value or a calculated value. In the case where the dynamic wheelbase is applied in the form of a predefined value, the predefined value can preferably be stored in a storage unit connected to the evaluation unit and can be read out by the evaluation unit when necessary. The storage unit can include a permanent memory for this purpose, the content of which is retained even after a power failure of the storage unit. Alternatively or additionally, the storage unit can have a volatile memory, which can preferably be used to store data received and calculated by the evaluation unit. The predefined value representing the dynamic wheelbase of the vehicle can be determined, for example, based on a measurement of the wheelbase of the vehicle and stored in the storage unit. In the case where the dynamic wheelbase is applied in the form of a calculated value, the method according to the invention described further below for calculating the corresponding current value of the dynamic wheelbase of the vehicle can be applied. It should be noted that according to the method according to the invention, in particular, a combination of the use of a predefined value for the dynamic wheelbase and the use of a calculated value for the dynamic wheelbase can be provided. In other words, the calculation of the dynamic tire circumference can first be realized initially with the aid of a predefined value for the dynamic wheelbase. Based on the subsequently calculated value for the dynamic tire circumference, a calculation of the dynamic wheelbase can also be correspondingly carried out, which can be used from this point in time as an alternative to the predefined value for the dynamic wheelbase.

[0016] In the second step of the method according to the invention, a first output signal of the first Kalman filter representing the dynamic tire circumference of the wheel is determined using the first signal, the second signal, the third signal and the fourth signal as input signals for the first Kalman filter. To this end, the first Kalman filter can advantageously be a filter having a state space model for calculating the dynamic tire circumference, which is implemented, for example, in the form of a computer program implemented by an analysis unit. The first Kalman filter can in particular be an extended Kalman filter, hereinafter referred to as an EKF filter, and preferably an unscented Kalman filter, hereinafter referred to as a UKF filter. The latter is particularly suitable for mapping nonlinearities in the state space model that is mapped respectively by the Kalman filter, which is important in particular in the calculation of the dynamic tire circumference and the dynamic wheelbase. The calculation of the dynamic tire circumference or the calculation of the dynamic wheelbase is preferably implemented based on the following equation:

[0017]

[0018] as well as

[0019]

[0020] represents the yaw rate of the vehicle, ω idenotes the wheel speed of the corresponding wheel of the vehicle (wherein the index i stands for RR: right rear, RL: left rear, FR: right front and FL: left front), δ denotes the steering angle of the vehicle (wherein the index j stands for R: rear and F: front), C denotes the dynamic tire circumference and T denotes the dynamic wheel width. It should be pointed out here that the method according to the invention can also be carried out based on individual wheel speed information of an individual wheel of the vehicle (e.g. the left front wheel) and that multiple wheel speeds of multiple wheels of the vehicle do not necessarily have to flow into the calculation. If multiple wheel speeds are fed into the first Kalman filter, for example, one wheel speed of the wheel of the vehicle can be determined as a reference variable, while the respective other wheel speeds flow into the first Kalman filter as virtual variables, which virtual variables can each relate to the reference variable.

[0021] In the third step of the method according to the invention, a first output signal is used in the control device of the vehicle, which first output signal represents the dynamic tire circumference of the vehicle. For this purpose, the value of the dynamic tire circumference calculated by the analysis unit according to the invention can be output to the vehicle network of the vehicle via the data output of the analysis unit. The vehicle network of the vehicle or the sub-vehicle network used for this purpose can be realized in the form of a CAN bus, a MOST bus, a FlexRay bus, a LIN bus or an Ethernet connection, for example. The control device can be connected to the vehicle network of the vehicle or the sub-vehicle network used in information technology, just like the analysis unit itself, and thus receives the signal representing the dynamic tire circumference sent by the analysis unit. The control device can be, for example, a driver assistance system, such as a parking assistance system, which can be set to perform the desired parking maneuver with correspondingly high accuracy based on the respective current calculated values ​​for the dynamic tire circumference. In addition, other driver assistance systems and / or operating systems of the vehicle can also be receivers for the respective current calculated values ​​of the dynamic tire circumference. Alternatively or additionally, corresponding values ​​for the dynamic tire circumference can also be received by a system for fully automatic vehicle control of a vehicle and used in the system for vehicle control.

[0022] Preferred embodiments of the invention are described below.

[0023] As described above, the dynamic wheelbase can be used based on a predefined estimated value or based on a calculated value. In the case of using a calculated value, the dynamic wheelbase can preferably be calculated by means of a second Kalman filter, whose input signals include the first signal, the second signal, the third signal and the first output signal of the first Kalman filter. The second Kalman filter can be a filter with a state space model for calculating the dynamic wheelbase, in particular a UKF filter and preferably an EKF filter. If the first output signal of the first Kalman filter is not yet available at the time of calculating the dynamic wheelbase (because the first output signal itself may not have been calculated), the predefined estimated value for the dynamic tire circumference can be fed into the second Kalman filter instead of the first output signal. The predefined estimated value for the dynamic tire circumference can also be stored in a storage unit connected to the evaluation unit. As soon as the dynamic tire circumference is present as a calculated value in the form of the first output signal of the first Kalman filter, the calculated value can be used as an input signal for the second Kalman filter in response thereto. In the case that initially neither the calculated value for the dynamic tire circumference nor the calculated value for the dynamic wheelbase should be present in the system, corresponding predefined estimated values ​​can first be used for both values. Subsequent calculation of the dynamic wheelbase and the dynamic tire circumference based on the current output signal of the respective other Kalman filter can therefore lead to a gradual approach of the corresponding values ​​to the actual, existing values ​​for the current dynamic wheelbase and the current dynamic tire circumference of the vehicle.

[0024] In another advantageous embodiment of the present invention, a fifth signal representing the position information of a satellite-based positioning system of a vehicle is additionally fed into the first Kalman filter as an input signal and used in the determination of the dynamic tire circumference. The satellite-based positioning system can be, for example, a GPS positioning system, a Galileo positioning system, or another positioning system known from the prior art. A corresponding receiving unit for a satellite-based positioning system can be arranged, for example, in a navigation unit of an onboard computer of a vehicle. Alternatively or additionally, such a receiving unit can also be set in a control unit different from that of a vehicle. By means of an information technology connection between a control device, which includes a receiving unit for a satellite-based positioning system, and an onboard network of a vehicle, the current position information of the vehicle received in the vehicle can be transmitted to the analysis unit according to the present invention through the onboard network. The analysis unit can, for example, first store the received data in a volatile memory of a storage unit and then feed these data into the first Kalman filter in the form of a fifth signal. The accuracy in the calculation of the dynamic tire circumference and thus also the dynamic wheelbase can be improved by additionally utilizing the respective current position information of the vehicle. Alternatively or additionally, by utilizing the position information, it is possible to shorten the duration for which the respectively calculated values ​​for the dynamic tire circumference and the dynamic wheelbase approach the actual value. The consideration of the position information can preferably be realized by the following equation:

[0025]

[0026] In another advantageous embodiment of the invention, the first output signal of the first Kalman filter is updated or not updated according to a predefined criterion. This can be advantageous in particular in the case that the quality of the currently existing input signal for the first Kalman filter is below a predefined threshold value and / or one or more of the input signals are not currently present, either in a case-dependent manner or due to a technical defect. In such a case, the computer program implemented by the evaluation unit can output the last calculated valid value for the dynamic tire circumference unchanged at the output of the first Kalman filter (i.e., independently of the input signal currently applied at the first Kalman filter) until the corresponding predefined criterion for calculating the dynamic wheelbase is met again. In addition to the above-mentioned predefined criteria, for example, the current driving direction and / or speed of the vehicle, the activation state of other functions or control devices in the vehicle (e.g., activated driving dynamics control, etc.), the type of the currently traveled section (e.g., off-road driving), etc. can also lead to the last calculated valid value being maintained at the output of the first Kalman filter. In addition, a predefined minimum training duration for the first Kalman filter that has not yet expired can also represent such a predefined criterion. The above-mentioned points can also apply in an analogous manner to the second Kalman filter and its input variables and can be used in this second Kalman filter in a similar manner as in the first Kalman filter.

[0027] In another advantageous embodiment of the invention, a second output signal representing the quality of the first output signal of the first Kalman filter is output by the first Kalman filter. This signal can generally be used for the evaluation of the current value of the dynamic tire circumference and / or for the above-mentioned updating or non-updating of the first output signal in the form of a predefined criterion. Alternatively, the second output signal can be used, for example, in the case of insufficient quality of the first output signal, to output a predefined estimated value for the dynamic tire circumference at the output of the first Kalman filter instead of the value for the calculation of the dynamic tire circumference. It also applies here that the measures described for the first Kalman filter can be used in an analogous manner for the second Kalman filter.

[0028] In a further advantageous embodiment of the invention, the determination of the dynamic tire circumference and / or the dynamic wheelbase is carried out at a longitudinal speed of the vehicle of 1 km / h to 200 km / h, in particular 3 km / h to 150 km / h and preferably 5 km / h to 130 km / h. By adhering to one or more of the proposed value ranges for the longitudinal speed of the vehicle, it can be ensured that the quality or reliability of the values ​​determined for the dynamic tire circumference and the dynamic wheelbase is sufficient for downstream processing of the corresponding values.

[0029] It should be noted that the above method steps and their advantageous configurations can be combined, modified and deleted in different ways within the scope of protection of the present invention. In a specific implementation of the method according to the invention, different modes for calculating the dynamic tire circumference and / or the dynamic wheelbase can be set by means of the computer program according to the invention, for example, and these different modes can be selected in a suitable manner according to predefined criteria and / or the quality of the output signals of the first and / or second Kalman filter and / or the signals available in the corresponding means of transport.

[0030] According to a second aspect of the invention, a device for determining the dynamic tire circumference of a vehicle is provided. The device comprises an analysis unit with a data input and a data output, and can be a component of an existing control device or an independent control device of the vehicle. In addition, the analysis unit can be configured, for example, as an ASIC, an FPGA, a processor, a digital signal processor, a microcontroller, etc., and can be connected to an internal and / or external storage unit in terms of information technology, in which the data received and / or calculated by the analysis unit can be stored for subsequent processing. In addition, the analysis unit can be configured to implement the above-mentioned method steps according to the invention based on a computer program that implements the method steps. The analysis unit is also configured to receive, in conjunction with the data input, a first signal representing the yaw rate of the vehicle, a second signal representing the wheel speed of the wheels of the vehicle, a third signal representing the steering angle of the vehicle, and a fourth signal representing the dynamic wheelbase of the vehicle. This can preferably be achieved by connecting the data input of the analysis unit to the vehicle network in terms of information technology, through which the analysis unit can receive the above-mentioned signals from other control devices of the vehicle. Furthermore, the evaluation unit is configured to determine a first output signal of the first Kalman filter, which represents the dynamic tire circumference of the wheel, using the first signal, the second signal, the third signal and the fourth signal as input signals for the first Kalman filter. In conjunction with the data output, the evaluation unit is additionally configured to use the first output signal in a control device of the vehicle. For this purpose, the data output of the evaluation unit can also be connected to the vehicle electrical system of the vehicle in an information technology manner, so that the evaluation unit can transmit the first output signal calculated by means of the first Kalman filter via the vehicle electrical system to one or more suitable receivers of the first output signal in the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Embodiments of the present invention are described in detail below with reference to the accompanying drawings. It is shown here:

[0032] Figure 1 A flow chart is shown which illustrates the steps of one embodiment of the method according to the present invention;

[0033] Figure 2 A block diagram showing a first Kalman filter for calculating the dynamic tire circumference of a vehicle according to the present invention;

[0034] Figure 3 A block diagram showing a second Kalman filter for calculating a dynamic wheelbase of a vehicle according to the present invention; and

[0035] Figure 4 A schematic overview of components of an apparatus according to the invention in combination with a means of transport is shown. DETAILED DESCRIPTION

[0036] Figure 1 A flow chart is shown which shows the steps of an exemplary embodiment of a method according to the invention for determining the dynamic tire circumference of a vehicle, which is a passenger car in this case. In a first step 100, an evaluation unit according to the invention, which is coupled to the vehicle network of the vehicle in terms of information technology, receives a first signal representing the yaw rate of the vehicle, a second signal representing the wheel speed of the wheels of the vehicle, a third signal representing the steering angle of the vehicle, and a fourth signal representing the dynamic wheel width of the vehicle, and stores the data represented by the signals in a storage unit which is connected to the evaluation unit in terms of information technology. In step 200, the first output signal of the first Kalman filter representing the dynamic tire circumference of the wheels is determined by the evaluation unit using the first signal, the second signal, the third signal and the fourth signal as input signals for the first Kalman filter. The first Kalman filter is a UKF filter in this case. The determination of the first output signal is realized based on a computer program which is executed by the evaluation unit and which maps a state space model for calculating the dynamic tire circumference. In a third step 300 , a first output signal of the UKF filter is transmitted via the onboard electrical system of the vehicle to a parking assistance system of the vehicle, which performs a fully automatic parking maneuver based on the first output signal.

[0037] Figure 2The block diagram of the first Kalman filter K1 according to the invention for calculating the dynamic tire circumference of a vehicle is shown. For this purpose, a first signal S1 representing the yaw rate of the vehicle, a second signal S2 representing the wheel speed of the wheels of the vehicle, a third signal S3 representing the steering angle of the vehicle and a fourth signal S4 representing the dynamic wheel track of the vehicle are fed into the input of the first Kalman filter K1. The fourth signal S4 representing the dynamic wheel track of the vehicle corresponds to the actual calculated value for the dynamic wheel track instead of an estimated value. Based on the input signals S1, S2, S3, S4 and based on a suitable state space model, the first Kalman filter K1 is set up to calculate a first output signal A1, which represents the dynamic tire circumference of the vehicle. In addition, a second output signal A2 is generated by the first Kalman filter K1, which represents a measure of the quality of the first output signal A1.

[0038] Figure 3 The block diagram of the second Kalman filter K2 according to the invention for calculating the dynamic wheelbase of a vehicle is shown. For this purpose, a first signal S1 representing the yaw rate of the vehicle, a second signal S2 representing the wheel speed of the wheels of the vehicle, a third signal S3 representing the steering angle of the vehicle and a first output signal A1 of the first Kalman filter K1 representing the dynamic tire circumference of the vehicle are fed into the input of the second Kalman filter K2. The first output signal A1 representing the dynamic tire circumference of the vehicle corresponds to the actual calculated value for the dynamic tire circumference instead of an estimated value. Based on the input signals S1, S2, S3, A1 and based on a suitable state space model, the second Kalman filter K2 is set up to calculate a fourth output signal S4, which represents the dynamic wheelbase of the vehicle.

[0039] Figure 4A schematic overview of the components of the device according to the invention in combination with a vehicle 80 is shown. The device according to the invention comprises an evaluation unit 10, which is a microcontroller in this case and which has a data input 12 and a data output 14. In addition, an external storage unit 20 is connected to the evaluation unit 10 in terms of information technology, in which the evaluation unit 10 can store received and / or calculated data. The evaluation unit 10 is configured to implement the above-described method steps according to the invention based on a computer program. The rotation rate sensor 50 of the vehicle 80 is connected in terms of information technology to the data input 12 of the evaluation unit 10 via a CAN bus of the onboard electrical system of the vehicle 80. In addition, a plurality of wheel speed sensors 60 of the respective wheels 85 of the vehicle 80 are also connected to the data input 12 of the evaluation unit 10 via the CAN bus. In addition, the steering angle sensor 70 and the GPS receiver 40 of the vehicle 80 are also connected to the data input 12 of the evaluation unit 10 via the CAN bus. In this way, the evaluation unit 10 is configured to receive a first signal representing a yaw rate from a rotation rate sensor 50, a second signal representing a wheel speed from a plurality of wheel speed sensors 60, a third signal representing a steering angle from a steering angle sensor 70, and a fifth signal representing position information from a GPS receiver 40 of the vehicle 80. In addition, the evaluation unit 10 receives a predefined estimate for a dynamic wheel track of the vehicle 80 from the storage unit 20. All of the above-mentioned received signals and the predefined estimate for the dynamic wheel track of the vehicle 80 are fed as input signals to a first Kalman filter in the evaluation unit 10 in order to calculate the dynamic tire circumference of the vehicle 80 based on these input signals. The first Kalman filter is implemented by means of a computer program executed by the evaluation unit 10. The result of the calculation of the dynamic tire circumference is transmitted to the parking assistance system 30 of the vehicle 80 by means of a data output 14 of the evaluation unit 10 via the CAN bus. The parking assistance system 30 then uses the information about the dynamic tire circumference in the execution of a fully automatic parking process of the vehicle 80.

Claims

1. A method for obtaining a dynamic tire circumference of a vehicle (80), the method comprising the following steps: Receiving (100) a first signal (S1) representing a yaw rate of the vehicle (80), a second signal (S2) representing a wheel speed of a wheel (85) of the vehicle (80), a third signal (S3) representing a steering angle of the vehicle (80), and a fourth signal (S4) representing a dynamic wheelbase of the vehicle (80); determining (200) a first output signal (A1) of the first Kalman filter (K1) representing the dynamic tire circumference of the wheel (85) using the first signal (S1), the second signal (S2), the third signal (S3) and the fourth signal (S4) as input signals for a first Kalman filter (K1); and The first output signal (A1) is used (300) in a control device (30) of the transport vehicle (80), wherein the dynamic wheelbase of the transport vehicle (80) is calculated based on the first output signal (A1) of the first Kalman filter (K1) representing the dynamic tire circumference of the wheel (85), and wherein the fourth signal (S4) is calculated based on the first signal (S1), the second signal (S2), the third signal (S3) and the first output signal (A1).

2. The method according to claim 1, wherein: The first Kalman filter (K1) is a filter having a state space model for calculating the dynamic tire circumference.

3. The method according to claim 2, wherein: The first Kalman filter (K1) is an extended Kalman filter, hereinafter referred to as an EKF filter.

4. The method according to claim 2, wherein: The first Kalman filter (K1) is an unscented Kalman filter, hereinafter referred to as UKF filter.

5. The method according to any one of claims 1 to 4, wherein: The dynamic wheelbase is a predefined estimated value for the dynamic wheelbase or is calculated with the aid of a second Kalman filter (K2), the input signal of the second Kalman filter comprising the first signal (S1), the second signal (S2), the third signal (S3) and the first output signal (A1) of the first Kalman filter (K1).

6. The method according to claim 5, wherein: The second Kalman filter (K2) is a filter having a state space model for calculating the dynamic wheelbase.

7. The method according to claim 6, wherein: The second Kalman filter (K2) is a UKF filter.

8. The method according to claim 6, wherein: The second Kalman filter (K2) is an EKF filter.

9. The method according to any one of claims 1 to 4, wherein: In addition, a fifth signal (S5) representing position information of a satellite-based positioning system (40) of the vehicle (80) is fed as an input signal into the first Kalman filter (K1) and used in determining the dynamic tire circumference.

10. The method according to any one of claims 1 to 4, wherein: The first output signal (A1) of the first Kalman filter (K1) is updated or not updated according to a predefined criterion.

11. The method according to any one of claims 1 to 4, wherein: A second output signal (A2) representing the quality of the first output signal (A1) of the first Kalman filter (K1) is outputted by the first Kalman filter (K1).

12. The method according to any one of claims 1 to 4, wherein: The dynamic tire circumference and / or the dynamic wheelbase are determined (200) at a longitudinal speed of the vehicle (80) of 1 km / h to 200 km / h.

13. The method according to claim 12, wherein: The dynamic tire circumference and / or the dynamic wheelbase are determined (200) at a longitudinal speed of the vehicle (80) of 3 km / h to 150 km / h.

14. The method according to claim 13, wherein: The dynamic tire circumference and / or the dynamic wheelbase are determined (200) at a longitudinal speed of the vehicle (80) of 5 km / h to 130 km / h.

15. The method according to any one of claims 1 to 4, wherein: A first output signal (A1) of the first Kalman filter (K1) is used in a driver assistance system (30) of the vehicle (80).

16. The method according to claim 15, wherein: A first output signal (A1) of the first Kalman filter (K1) is used in a control system of the vehicle (80).

17. The method according to claim 15, wherein: A first output signal (A1) of the first Kalman filter (K1) is used in a parking assistance system of the vehicle (80).

18. The method according to any one of claims 1 to 4, wherein: A plurality of second signals (S2) representing a plurality of wheel speeds of a plurality of wheels (85) of the vehicle (80) flows into the first Kalman filter (K1).

19. A device for obtaining the dynamic tire circumference of a vehicle (80), the device comprising: An analysis and processing unit (10); Data input terminal (12); as well as Data output terminal (14); Wherein, the analysis and processing unit (10) is configured as follows: receiving, in conjunction with the data input terminal (12), a first signal (S1) representing a yaw rate of the vehicle (80), a second signal (S2) representing a wheel speed of a wheel (85) of the vehicle (80), a third signal (S3) representing a steering angle of the vehicle (80), and a fourth signal (S4) representing a dynamic wheelbase of the vehicle (80); determining a first output signal (A1) of the first Kalman filter (K1) representing the dynamic tire circumference of the wheel (85) by using the first signal (S1), the second signal (S2), the third signal (S3) and the fourth signal (S4) as input signals for a first Kalman filter (K1); and The first output signal (A1) is used in combination with the data output terminal (14) in the control device (30) of the vehicle (80), wherein the dynamic wheelbase of the vehicle (80) is calculated based on the first output signal (A1) of the first Kalman filter (K1) representing the dynamic tire circumference of the wheel (85), and wherein the fourth signal (S4) is calculated based on the first signal (S1), the second signal (S2), the third signal (S3) and the first output signal (A1).

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