Apparatus and method for parameter estimation of a brake system of a vehicle equipped with a motorized piston cylinder device

Abstract

The invention relates to a device (10) and a method for parameter estimation of a brake system of a vehicle equipped with a motorized piston cylinder device (12) by the following means: operating an electric motor (14) of the motorized piston cylinder device (12) such that at least one piston of the motorized piston cylinder device (12) movable by means of the operated electric motor (14) is moved from its respective starting position; determining or estimating a brake liquid volume displaced by means of the at least one movable piston of the motorized piston cylinder device (12) between the motorized piston cylinder device (12) and at least one part of the brake system adjoining the motorized piston cylinder device (12); determining or estimating a pressure change occurring at least in the part of the brake system adjoining the motorized piston cylinder device (12) as a result of the displaced brake liquid volume; and determining a resilience (E) of the brake system and / or a stiffness (∑) of the brake system at least taking into account the determined or estimated displaced brake liquid volume and the determined or estimated pressure change.

Description

Technical Field

[0001] This invention relates to an apparatus for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device, and to a braking system for a vehicle. Similarly, this invention relates to a method for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device. Furthermore, this invention also relates to a method for operating a braking system of a vehicle equipped with a motorized piston-cylinder device. Background Technology

[0002] It is known from the prior art, such as DE 10 2017 212 360 A1, that a braking system is equipped with a motorized piston cylinder device, which may also be called a motorized plunger device, and that the braking system is equipped with a device or control device for operating an electric motor for operating the motorized piston cylinder device. Summary of the Invention

[0003] The present invention provides an apparatus for estimating parameters of a braking system of a vehicle equipped with a automatonized piston cylinder device, having the features of claim 1; a braking system for a vehicle, having the features of claim 8; a method for estimating parameters of a braking system of a vehicle equipped with a automatonized piston cylinder device, having the features of claim 9; and a method for operating a braking system of a vehicle equipped with a automatonized piston cylinder device, having the features of claim 10.

[0004] Advantages of the invention

[0005] This invention presents advantageous possibilities for determining at least one elasticity or stiffness as a necessary parameter in the inverse system model of a braking system of a vehicle equipped with a motorized piston-cylinder device. In particular, this invention proposes "robust" possibilities for determining the elasticity and / or stiffness of the corresponding braking system, in which variables that impair elasticity and / or stiffness can also be considered. Thus, even under extreme boundary conditions, this invention ensures the reliable determination of the elasticity and / or stiffness of the corresponding braking system. Specifically, the elasticity and / or stiffness of the corresponding braking system can be adapted to production-related factors, deviations from its standard braking system type, changes due to aging of the corresponding braking system, and / or to unpredictable environmental influences affecting the corresponding braking system. In all the cases listed herein, the elasticity and / or stiffness of the corresponding braking system can be reliably determined. Therefore, this invention also supports low-cost mass production of braking systems equipped with motorized piston-cylinder devices, because even if one braking system deviates from its typical product series, the elasticity and / or stiffness of that braking system can still be reliably determined using this invention.

[0006] An advantageous embodiment of the device includes a first low-pass filter and / or a second low-pass filter, wherein the computer device is designed and / or programmed to determine the elasticity and / or stiffness of the braking system, at least taking into account the unfiltered or filtered (by means of the first low-pass filter) displacement of the brake fluid volume and the unfiltered or filtered (by means of the second low-pass filter) pressure variation. The low-pass filtering performed by means of the first and / or second low-pass filters limits / reduces signal noise appearing on the respective filtered signals.

[0007] Preferably, the computer device is additionally designed and / or programmed to estimate the movement path of at least one piston of the motorized piston cylinder device, which is moved by means of a controlled electric motor, from its respective starting position, or to read the movement path from at least one movement path sensor signal provided to the computer device. The computer device is designed and / or programmed to estimate, based on the estimated or read movement path of at least one moved piston, the volume of brake fluid displaced by at least one movable piston between the motorized piston cylinder device and at least the adjacent portion of the braking system of the braking system. Since motorized piston cylinder devices are conventionally equipped with at least one movement path sensor, such as, for example, the angle sensor of its electric motor, a reliable estimate of the displaced brake fluid volume can be easily determined using the embodiment of the device described herein, thereby eliminating the need for additional sensing mechanisms for measuring the displaced brake fluid volume.

[0008] In another advantageous embodiment of the device, the computer device is additionally designed and / or programmed to estimate the storage volume temporarily stored in at least one reservoir of the braking system, or to read the storage volume from at least one reservoir sensor signal provided to the computer device. The computer device is also designed and / or programmed to determine the elasticity and / or stiffness of the braking system, at least taking into account the estimated or read-out displaced brake fluid volume, the estimated or read-out pressure change, and the storage volume temporarily stored in at least one reservoir. Thus, the embodiment of the device described herein enables more accurate and reliable determination of the elasticity and / or stiffness of the corresponding braking system.

[0009] Similarly, the motor control device can be additionally designed and / or programmed to operate the electric motor of the motorized brake pressure building device of the braking system, such that the motorized brake pressure building device can shift a volume difference into or out of at least the portion of the adjacent motorized piston cylinder device of the braking system, wherein the computer device is additionally designed and / or programmed to estimate the volume difference, or read the volume difference from at least one additional volume sensor signal provided to the computer device, and to determine the elasticity and / or stiffness of the braking system, at least taking into account the estimated or read-out shifted brake fluid volume, the estimated or read-out pressure change, and the volume difference shifted into or out of the portion of the adjacent motorized piston cylinder device of the braking system. In this way, the elasticity and / or stiffness of the corresponding braking system can also be determined more accurately and reliably.

[0010] Alternatively or supplementarily, the computer device may also be designed and / or programmed to: estimate the dead zone volume of the braking system, at least taking into account the estimated or read-out displacement of brake fluid and the estimated or read-out pressure change; and determine the elasticity and / or stiffness of the braking system, at least taking into account the estimated or read-out displacement of brake fluid, the estimated or read-out pressure change, and the estimated dead zone volume. Estimating and considering the dead zone volume of the braking system can also help improve the accuracy and reliability of the measured elasticity or stiffness of the corresponding braking system.

[0011] As an advantageous extension, the motor control device can be additionally designed and / or programmed to: determine at least one desired variable regarding the desired operating mode of the motor of the motorized piston-cylinder device, taking into account at least one preset variable concerning the vehicle speed and / or vehicle deceleration required by the vehicle's driver or speed automatic device, and additionally considering the elasticity and / or stiffness of the braking system as determined by a computer device; and, taking into account at least the determined desired variable, output at least one motor control signal to the motor. With the extension described herein, both enhanced braking force and autonomous braking of the corresponding vehicle can be achieved, wherein, by considering the determined elasticity and / or stiffness of the corresponding braking system, reliable compliance with the required vehicle speed and / or vehicle deceleration is ensured in both cases.

[0012] Even in braking systems for vehicles that have such devices for parameter estimation and motorized piston cylinder devices, the advantages described above are guaranteed, as the motorized piston cylinder devices have an electric motor that can be controlled by means of such devices.

[0013] The method for estimating the parameters of a braking system equipped with a automatonized piston-cylinder device in a vehicle also achieves the advantages described above. Based on the embodiment of the device described above, the method for parameter estimation can be extended.

[0014] Furthermore, the method of implementing a braking system equipped with a motorized piston cylinder device for operating a vehicle also achieves the advantages described above, wherein the method can be extended according to the embodiment of the device described above. Attached Figure Description

[0015] Subsequently, other features and advantages of the invention are described with reference to the accompanying drawings.

[0016] Figure 1 A flowchart illustrating an implementation of a method for estimating parameters of a braking system equipped with an automated piston-cylinder device in a vehicle is shown.

[0017] Figure 2 A flowchart illustrating an embodiment of a method for describing a braking system equipped with a motorized piston-cylinder device for operating a vehicle is shown; and

[0018] Figure 3a and 3b A schematic partial illustration of an implementation of the braking system and a coordinate system for illustrating its pressure-volume characteristic curves are shown. Detailed Implementation

[0019] Figure 1 A flowchart illustrating an implementation of a method for estimating parameters of a braking system equipped with a motorized piston-cylinder device in a vehicle is shown.

[0020] The method described below can be performed using (almost) any braking system equipped with at least a motorized piston-cylinder device, also referred to as a motorized plunger device. A motorized piston-cylinder device is to be understood as a device having at least one piston arranged within a cylinder-shaped volume, wherein at least one piston is linearly movable and / or moved by means of an electric motor of the motorized piston-cylinder device, such that brake fluid is displaceable between at least one cylinder-shaped volume of the motorized piston-cylinder device and the connected braking system volume. The feasibility of this method is also not limited to a specific vehicle type / motor vehicle equipped with the corresponding braking system.

[0021] In method step S1, the motor of the motorized piston cylinder device is operated such that at least one movable piston of the motorized piston cylinder device, by means of the operated motor, moves from its respective starting position. Additionally, when performing the method described herein, the brake fluid volume ΔV displaced by at least one movable piston of the motorized piston cylinder device between the motorized piston cylinder device and at least one adjacent portion of the braking system of the motorized piston cylinder device is estimated or determined.

[0022] For example, the movement path of at least one movable piston of the motorized piston cylinder device (by means of a controlled electric motor) from its respective starting position can be estimated, or the movement path can be read from at least one movement path sensor signal. Then, based on the estimated movement path of at least one volume, the brake fluid volume ΔV displaced by at least one movable piston between the motorized piston cylinder device and at least the adjacent portion of the braking system of the braking system can be estimated. For example, based on the control of the electric motor performed as method step S1, the movement path of at least one movable piston can be estimated with high accuracy and good reliability by, for example, correspondingly evaluating the current output to the electric motor for its control. Alternatively or supplementarily, the movement path of at least one movable piston can also be read from the signal of the angle sensor of the motor of the motorized piston cylinder device, which is evaluated as a movement path sensor signal. Alternatively, at least one specific sensor can be installed on the motorized piston cylinder device to determine the current position of at least one piston, and the signal of this sensor is then evaluated as a movement path sensor signal for reading the movement path of at least one piston. As long as at least one volume sensor designed to determine the brake fluid volume ΔV displaced by means of at least one movable piston is installed on the braking system, the displaced brake fluid volume ΔV can also be read from at least one volume sensor signal of at least one volume sensor.

[0023] By way of example only, in the method described herein, as method step S2, in order to determine the brake fluid volume ΔV displaced by at least one movable piston, the total brake fluid volume V(t) of the braking system is continuously estimated or determined. The estimation or determination of the total brake fluid volume V(t) of the braking system can be made by taking into account the corresponding movement path of at least one piston moved by a controlled electric motor, at least one movement path sensor signal and / or at least one volume sensor signal.

[0024] Furthermore, when performing the method described herein, the pressure change Δp that occurs at least in the adjacent motorized piston cylinder portion of the braking system due to the displaced brake fluid volume ΔV is determined or estimated. As the corresponding pressure change Δp, for example, a change in inlet pressure (Vordruck) can be estimated, or the change in inlet pressure can be measured using at least one inlet pressure sensor. Exemplarily, in the embodiment described herein, as method step S3, the dominant pressure p(t) in at least the adjacent motorized piston cylinder portion of the braking system is continuously determined or estimated. Preferably, when performing method steps S2 and S3, care is taken to ensure that there is no large time delay between the determined or estimated value for the total brake fluid volume V(t) and the pressure p(t).

[0025] exist Figure 1 In this implementation, immediately following in (optional) method step S4, the determined or estimated total brake fluid volume V(t) is filtered using a variable low-pass filter. Similarly, in (optional) method step S5, the determined or estimated pressure p(t) can be filtered using another variable low-pass filter. By using the low-pass filtering performed as method steps S4 and S5, signal noise can be limited to the volume value V(t) and pressure value p(t), or to the values ​​subsequently derived therefrom for the shifted brake fluid volume ΔV and pressure change Δp.

[0026] In method step S6, the displaced brake fluid volume ΔV is then determined according to equation (Gl.1), where

[0027]

[0028] Correspondingly, in method step S7, the pressure change Δp is determined according to equation (Gl.2), where

[0029]

[0030] In (optional) method step S8, in the embodiment described herein, the pressure change Δp determined in method step S7 will be compared with a pre-given minimum pressure change Δp. min Compare the results. If the pressure change Δp is greater than the minimum pressure change Δp... min Then, the method can be continued with (optional) method step S9. As method step S9, the displaced brake fluid volume ΔV determined in method step S6 can be compared with a pre-given minimum volume change ΔV. min A comparison is made. As long as the determined displaced brake fluid volume ΔV is greater than the minimum volume change ΔV... min Then, the method can be continued using method step S10.

[0031] In method step S10, the elasticity E and / or stiffness ∑ of the braking system are determined, at least considering the displaced brake fluid volume ΔV and pressure change Δp. Figure 1 In the implementation described here, the elasticity of the braking system, in particular, is determined according to equation (G1.3), where

[0032]

[0033] Therefore, equation (G1.3) can be used reliably, because step S8 ensures that the pressure change Δp is sufficiently large. (In the case where the pressure change Δp is almost zero, the elasticity E determined in this way may tend to infinity). Step S9 further ensures that the elasticity E determined according to equation (G1.3) is significantly different from zero.

[0034] Alternatively, or as a supplement, the stiffness ∑ of the braking system can also be determined according to equation (Gl.4), where

[0035]

[0036] As an advantageous extension, more complex equations can also be used in method step S10 to determine the elasticity E and / or stiffness ∑ of the braking system. For example, in at least one method step (not shown), the storage volume V temporarily stored in at least one storage compartment of the corresponding braking system can also be estimated or read from at least one storage compartment sensor signal. acc If necessary, then at least the displaced brake fluid volume ΔV, pressure change Δp, and storage volume V temporarily stored in at least one reservoir should be considered. acc In this case, the elasticity E and / or stiffness ∑ of the braking system can be measured. Furthermore, provided the braking system also has at least one additional motorized brake pressure building device, the volume difference V of at least the portion of the adjacent motorized piston cylinder device that shifts into or out of the braking system via the motorized brake pressure building device can also be estimated or determined. diff Accordingly, at least considering the displaced brake fluid volume ΔV, the pressure change Δp, and the volume difference V of at least the portion of the adjacent motorized piston cylinder device that is displaced into or out of the braking system. diffIn such cases, the elasticity E and / or stiffness ∑ of the corresponding braking system can be determined. Furthermore, in many braking systems, the so-called dead zone volume V0 must be exceeded only before pressure buildup in the corresponding braking system begins by operating at least a motorized piston-cylinder device. If this applies to the corresponding braking system, the elasticity E and / or stiffness ∑ of the braking system can also be determined, at least considering the displaced brake fluid volume ΔV, the pressure change Δp, and the estimated dead zone volume V0. Therefore, equations (Gl.5) and / or (Gl.6) can also be used to determine the elasticity E or stiffness ∑ of the braking system, where:

[0037]

[0038]

[0039] variable V + Optionally, it may include: a storage volume V temporarily stored in at least one storage room. acc The volume difference V for equipment displacement is established by using the braking pressure of motorization. diff And / or dead zone volume V0.

[0040] As a possible extension, even when determining the elasticity E and / or stiffness ∑ of the corresponding braking system, attention can also be paid to the damping D and / or inertia T of the corresponding braking system. This can be achieved using equations (Gl.7) and / or (Gl.8), where:

[0041]

[0042]

[0043] However, it should be noted that the use of the following six parameters is optional: elasticity E / stiffness ∑, storage volume V acc Volume difference V diff Dead zone volume V0, damping D, and inertia T. Instead of using equation (Gl.7) or the equation derived therefrom for elasticity E, which is complex and computationally intensive, often only equations (Gl.3) and (Gl.4) can be used to determine elasticity E and / or stiffness ∑. To ensure that the storage volume V of the corresponding braking system is... acc Volume difference V diff The dead zone volume V0, damping D, and inertia T do not play a relevant role in determining the elasticity E and / or stiffness ∑ of the corresponding braking system. Furthermore, the corresponding test boundary conditions can be followed when determining the parameters. Following these test boundary conditions can be ensured, for example, by signal filtering performed using method steps S4 and S5.

[0044] The method steps described below also ensure that the value E determined by equation (G1.3) is a reliable value of the elasticity E. To this end, in (optional) method step S11, the value E determined by equation (G1.3) is first compared with a pre-given maximum value E for the elasticity. max Compare the values. If the value E determined using equation (Gl.3) is less than the maximum value E... max The method then continues with (optional) method step S12, in which the value E determined by means of equation (Gl.3) is compared with a predetermined minimum value E for elasticity. min A comparison is made. Only when the value E determined by equation (Gl.3) is greater than the minimum value E... min Only then, in method step S13, is the value E determined as elasticity E.

[0045] If the pressure change Δp measured in step S7 is less than or equal to the minimum pressure change Δpm in In step S6 of the method, the displaced brake fluid volume ΔV is less than or equal to the minimum volume change ΔV. min Alternatively, the value E determined using equation (G1.3) is greater than or equal to the maximum value E. max In the implementation described here, method step S14 (optional) is performed. In method step S14, it is queried whether a previously valid value for elasticity E exists. If so, then as method step S15, the previously valid value is determined to be value E, and the method ends with method step S13. Otherwise, in method step S16, the maximum value E is determined. max The value is determined to be E, and the method ends with step S13.

[0046] Even if the value E measured by equation (G1.3) is less than or equal to the minimum value E min Then, method step S14 is executed. If a previously valid value for elasticity E exists, then method steps S13 and S15 are executed. Otherwise, as in method step S17, the minimum value E is determined. min The value is determined to be E, and the method ends with step S13.

[0047] Figure 2 A flowchart is shown illustrating an implementation of a method for describing a braking system equipped with a motorized piston cylinder device for operating a vehicle.

[0048] The method described herein can also be performed using (almost) any braking system equipped with at least a automatonized piston-cylinder device. Similarly, the feasibility of this method is not limited to any particular vehicle type / motor vehicle equipped with the corresponding braking system.

[0049] In the method described herein, the elasticity E and / or stiffness ∑ of the braking system are first determined. This can be done, for example, by performing at least some of the method steps S1 to S17 described above.

[0050] Later, as method step S18, considering at least one preset variable regarding the vehicle speed and / or vehicle deceleration requested by the vehicle's driver or speed automatic device, and additionally considering the measured elasticity E and / or stiffness ∑ of the braking system, at least one desired variable regarding the desired operating mode of the electric motor of the motorized piston cylinder device is determined. The speed automatic device can be understood as, for example, an adaptive cruise control system, an automatic device for autonomous driving of the vehicle, and / or an emergency braking system. In particular, the braking pressure p to be achieved in at least one wheel brake cylinder of the braking system can first be determined. target With the help of the braking pressure p target Typically, the required vehicle speed and / or vehicle deceleration can be achieved. Subsequently, the volumetric flow rate q to be achieved using a motorized piston-cylinder device can be determined as at least one desired variable according to equation (Gl.9), with which the desired braking pressure P can be established in at least one wheel brake cylinder. target ,in:

[0051]

[0052] In another method step S19, taking into account at least the measured desired variable, the motor is operated by outputting at least one motor control signal to the motor of the motorized piston cylinder device. For example, as the at least one motor control signal, a current signal is output to the motor such that the energized motor triggers the desired volumetric flow rate q by means of the movement of at least one piston of the motorized piston cylinder device.

[0053] Figure 3a and 3b A schematic partial illustration of an implementation of the braking system and a coordinate system for illustrating the pressure-volume characteristic curves of the braking system are shown.

[0054] exist Figure 3a The braking system, schematically reproduced in the diagram, has at least one device 10 for parameter estimation and a motorized piston cylinder device 12, which has an electric motor 14 operable by means of the device 10. At least one piston of the motorized piston cylinder device 12 is linearly movable by means of the operation of its electric motor 14, such that the brake fluid is displaceable between the motorized piston cylinder device 12 and the remaining volume of the braking system.

[0055] exist Figure 3aThe diagram also shows, as exemplary components of the braking system: a master brake cylinder 16 with an upstream brake pedal 18, a brake fluid reservoir 20, a first disconnect valve 22a for connecting or disconnecting the first chamber of the master brake cylinder 16 from a (not sketched) first brake circuit of the braking system, a second disconnect valve 22b for connecting or disconnecting the second chamber of the master brake cylinder 16 from a (not shown) second brake circuit of the braking system, a third disconnect valve 24a for connecting or disconnecting the motorized piston cylinder device 12 from the first brake circuit, a fourth disconnect valve 24b for connecting or disconnecting the motorized piston cylinder device 12 from the second brake circuit, a fifth disconnect valve 26 for connecting the motorized piston cylinder device 12 to the brake fluid reservoir 20, and a simulator disconnect valve 28 for connecting or disconnecting the simulator 30 from the first chamber of the master brake cylinder 16. Each of the two brake circuits of the braking system includes at least one wheel brake cylinder. For example, each of the two brake circuits may have two wheel brake cylinders. Alternatively, at least one of the two braking circuits may also be configured to have at least one wheel intake valve, at least one wheel exhaust valve, and at least one reservoir and / or circulation pump disposed downstream of the wheel exhaust valve. However, omitting the... Figure 3a The diagram shows a graphical representation of the various components of the two braking circuits. It is further clarified that the components of the braking system described in this paragraph are to be interpreted as exemplary only. The applicability of the device 10 described below is not limited to such a braking system, or to a specific vehicle type / motor vehicle equipped with such a braking system.

[0056] The device 10 includes a motor control unit 32 designed and / or programmed to operate an electric motor 14 of a motorized piston cylinder device 12 by means of at least one motor control signal 34, such that at least one movable piston of the motorized piston cylinder device 12 is movable from its respective starting position by means of the controlled electric motor 14. Additionally, the device 10 includes a computer device 36 designed and / or programmed to estimate the brake fluid volume displaced by at least one movable piston between the motorized piston cylinder device 12 and at least one adjacent portion of the braking system of the motorized piston cylinder device 12, or to read the brake fluid volume from at least one volume sensor signal provided to the computer device 36, and to estimate the pressure change resulting from the displaced brake fluid volume at least in the adjacent portion of the braking system of the motorized piston cylinder device 12, or to read the pressure change from at least one pressure sensor signal 38 provided to the computer device 36. For example, at least one pressure sensor signal 38 can be output to the computer device 36 from an inlet pressure sensor 40. In the embodiment described herein, the computer device 36 is further designed and / or programmed to read from at least one movement path sensor signal 42 provided to the computer device 36 the movement path of at least one piston of the motorized piston cylinder device 12, moved by means of a controlled electric motor 14, from its respective starting position, and then, based on the estimated or read movement path of the at least one moved piston, to estimate the volume of brake fluid displaced by means of at least one movable piston between the motorized piston cylinder device 12 and at least the portion of the braking system adjacent to the motorized piston cylinder device 12. In particular, at least one movement path sensor signal 42 can be output to the computer device 36 from the angle sensor 44 of the electric motor 14.

[0057] The computer device 36 is additionally designed and / or programmed to determine the elasticity E and / or stiffness ∑ of the braking system, at least taking into account the estimated or read-out displaced brake fluid volume and the estimated or read-out pressure change. This can be done, in particular, by means of at least one of the equations described above. Even if the braking system has "unusual" elasticity E or stiffness ∑ due to its mass production, aging, or changes caused by environmental conditions, the corresponding values ​​can be reliably determined by means of the device 10. Figure 3b In the coordinate system, an example of the characteristic curve k of the elasticity E of the braking system, which can be measured by computer device 36, is plotted. The horizontal axis of the coordinate system displays the pressure p in the braking system, while the vertical axis displays the total brake fluid volume V of the braking system. Furthermore, in Figure 3b The dead zone volume V0 of the braking system is also reproduced in the coordinate system.

[0058] As an extension of non-graphical reproduction, device 10 may also have a first low-pass filter and / or a second low-pass filter, and computer device 36 may be designed and / or programmed to determine the elasticity E and / or stiffness ∑ of the braking system, at least considering the unfiltered or filtered by the first low-pass filter of the displaced brake fluid volume and the unfiltered or filtered by the second low-pass filter of the pressure change. Similarly, computer device 36 may also be designed and / or programmed to estimate the storage volume temporarily stored in at least one (undrawn) reservoir of the braking system, or to read the storage volume from at least one reservoir sensor signal provided to the computer device, and / or to estimate the dead zone volume V0 of the braking system. In this case, computer device 36 is preferably also designed and / or programmed to determine the elasticity E and / or stiffness ∑ of the braking system, also considering the storage volume temporarily stored in at least one reservoir and / or the estimated dead zone volume V0. As long as the motor control device 32 operates the electric motor of the motorized brake pressure building device (not shown) of the braking system so that the volume difference can be shifted into or away from at least the portion of the adjacent motorized piston cylinder device of the braking system by means of the motorized brake pressure building device, the computer device 36 can additionally design and / or program to estimate the volume difference, or read the volume difference from at least one additional volume sensor signal provided to the computer device, and, in addition to taking into account the volume difference of the portion of the adjacent motorized piston cylinder device shifted into or away from the braking system, determine the elasticity E and / or the stiffness ∑ of the braking system.

[0059] As an advantageous extension, in the embodiment of device 10 described herein, the motor control device 32 is also designed and / or programmed to determine at least one desired variable regarding the desired operating mode of the motor 14 of the motorized piston cylinder device, taking into account at least one preset variable 46 concerning the vehicle speed and / or vehicle deceleration requested by the vehicle's driver or speed automatic device, and additionally considering the elasticity E and / or stiffness ∑ of the braking system as determined by the computer device 36. For example, at least one preset variable 46 can also be provided to the motor control device 32 by a rod displacement sensor 48 and / or a differential displacement sensor. Then, taking into account at least the determined desired variable, the motor control device 32 outputs at least one motor control signal 34 to the motor 14. Therefore, device 10 can also be used for active or autonomous pressure modulation.

Claims

1. A device (10) for estimating parameters of a braking system of a vehicle equipped with an automated piston-cylinder device (12), comprising: A motor control device (32) is designed and / or programmed to operate an electric motor (14) of the motorized piston cylinder device (12) such that, by means of the operated electric motor (14), at least one movable piston of the motorized piston cylinder device (12) can be moved from a corresponding starting position; and A computer device (36) is designed and / or programmed to estimate, by means of the at least one movable piston, the brake fluid volume (ΔV) displaced between the motorized piston cylinder device (12) and at least one portion of the braking system adjacent to the motorized piston cylinder device (12), or to read the brake fluid volume (ΔV) from at least one volume sensor signal provided to the computer device (36), and to estimate, due to the displaced brake fluid volume (ΔV), at least in the portion of the braking system adjacent to the motorized piston cylinder device (12), the pressure change (Δp) is read from at least one pressure sensor signal (38) provided to the computer device (36); Its features are, The computer device (36) is additionally designed and / or programmed to determine the elasticity (E) of the braking system, at least taking into account the estimated or read-out displaced brake fluid volume (ΔV) and the estimated or read-out pressure change (Δp). The motor control device (32) is additionally designed and / or programmed to: determine at least one desired variable regarding the desired operating mode of the motor (14) of the motorized piston cylinder device (12), taking into account at least one preset variable (46) regarding the vehicle speed and / or vehicle deceleration required by the driver or speed automatic device of the vehicle, and additionally taking into account the elasticity (E) of the braking system as determined by the computer device (36); and output at least one motor control signal (34) to the motor (14) taking into account at least the determined desired variable.

2. The apparatus (10) for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device (12) according to claim 1, wherein, The device (10) has a first low-pass filter and / or a second low-pass filter, and the computer device (36) is designed and / or programmed to determine the elasticity (E) and / or stiffness (Σ) of the braking system, at least taking into account the unfiltered or filtered by the first low-pass filter displacement of the brake fluid volume (ΔV) and the unfiltered or filtered by the second low-pass filter pressure change (Δp).

3. The apparatus (10) for estimating parameters of a braking system of a vehicle equipped with a motorized piston cylinder device (12) according to claim 1, wherein, The computer device (36) is additionally designed and / or programmed to estimate the movement path of at least one piston of the motorized piston cylinder device (12) moved by means of the controlled electric motor (14) from its respective starting position, or to read the movement path from at least one movement path sensor signal (42) provided to the computer device (36); and wherein the computer device (36) is designed and / or programmed to estimate, based on the estimated or read movement path of at least one moved piston, the brake fluid volume (ΔV) displaced by means of the at least one movable piston between the motorized piston cylinder device (12) and at least the portion of the braking system adjacent to the motorized piston cylinder device (12).

4. The apparatus (10) according to any one of claims 1-3 for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device (12), wherein, The computer device (36) is additionally designed and / or programmed to estimate the storage volume (V) temporarily stored in at least one storage compartment of the braking system. acc ), or read the storage volume (V) from at least one storage compartment sensor signal provided to the computer device (36). acc ); and wherein the computer device (36) is designed and / or programmed to, at least when considering the estimated or read-out displaced brake fluid volume (ΔV), the estimated or read-out pressure change (Δp), and the storage volume (V) temporarily stored in the at least one storage chamber. acc In the case of ), the elasticity (E) and / or stiffness (Σ) of the braking system are measured.

5. The apparatus (10) for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device (12) according to any one of claims 1-3, wherein, The motor control device (32) is additionally designed and / or programmed to operate the electric motor of the motorized brake pressure building device of the braking system, so that the motorized brake pressure building device can, by means of the volume difference (V) diff The portion of the piston cylinder device (12) adjacent to the motorized piston cylinder device (12) is shifted into or out of the braking system; and wherein the computer device (36) is additionally designed and / or programmed to estimate the volume difference (V). diff ), or read the volume difference (V) from at least one other volume sensor signal provided to the computer device (36). diff Moreover, at least considering the estimated or read-out displacement of brake fluid volume (ΔV), the estimated or read-out pressure change (Δp), and the volume difference (Vp) of the displacement into or out of the braking system at least the portion adjacent to the motorized piston cylinder device (12). diff In the case of ), the elasticity (E) and / or stiffness (Σ) of the braking system are measured.

6. The apparatus (10) for estimating parameters of a braking system of a vehicle equipped with a motorized piston-cylinder device (12) according to any one of claims 1-3, wherein, The computer device (36) is additionally designed and / or programmed to estimate the dead zone volume (V0) of the braking system, at least taking into account the estimated or read-out displaced brake fluid volume (ΔV) and the estimated or read-out pressure change (Δp), and to determine the elasticity (E) and / or the stiffness (Σ) of the braking system, at least taking into account the estimated or read-out displaced brake fluid volume (ΔV), the estimated or read-out pressure change (Δp), and the estimated dead zone volume (V0).

7. A braking system for a vehicle, comprising: The apparatus (10) for estimating parameters of a braking system of a vehicle equipped with a motorized piston cylinder device (12) according to any one of claims 1-6; and A motorized piston cylinder device (12) having an electric motor (14) operable by means of the device (10).

8. A method for estimating parameters of a braking system of a vehicle equipped with an automated piston-cylinder device (12), comprising the steps of: An electric motor (14) controls the motorized piston cylinder device (12) so that at least one piston of the motorized piston cylinder device (12) moves from its respective starting position by means of the operating electric motor (14). Determine or estimate (S2, S6) the brake fluid volume (ΔV) displaced by at least one movable piston of the motorized piston cylinder device (12) between the motorized piston cylinder device (12) and at least one portion of the braking system adjacent to the motorized piston cylinder device (12); and Determine or estimate (S3, S7) the pressure change (Δp) that occurs at least in the portion of the braking system adjacent to the motorized piston cylinder device (12) due to the displaced brake fluid volume (ΔV). Its features The following steps are required: The elasticity (E) of the braking system is determined (S10) at least taking into account the determined or estimated displaced brake fluid volume (ΔV) and the determined or estimated pressure change (Δp). Taking into account at least one preset variable (46) regarding the vehicle speed and / or vehicle deceleration required by the vehicle's driver or speed automatic device, and additionally considering the elasticity (E) of the braking system measured by the computer device (36), at least one desired variable regarding the desired operating mode of the electric motor (14) of the motorized piston cylinder device (12) is determined, and Taking into account at least the measured expected variables, at least one motor control signal (34) is output to the motor (14).

9. A method for a braking system for operating a vehicle equipped with an automated piston cylinder device (12), comprising the steps of: The elasticity (E) of the braking system is determined according to the method for parameter estimation of a braking system equipped with an automated piston-cylinder device (12) for a vehicle as described in claim 8; and Taking into account at least one preset variable regarding the vehicle speed and / or vehicle deceleration required by the driver or speed automatic device of the vehicle, and additionally considering the measured elasticity (E) of the braking system, at least one desired variable regarding the desired operating mode of the electric motor (14) of the motorized piston cylinder device (12) is determined (S18); and Taking into account at least the measured expected variables, the motor (14) is operated (S19) by outputting at least one motor control signal (34) to the motor (14) of the motorized piston cylinder device (12).

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