METHOD, CONTROL DEVICE AND SYSTEM FOR STABILIZING A VEHICLE

Abstract

A method for stabilizing a vehicle (100) in which the vehicle (100) has a roll stabilizer (120), which is designed to stabilize a first axle (101) and a second axle (102) as a function of a roll torque distribution between the first axle (101) and the second axle (102). The method comprises a step of determining a sideslip angle index from a difference between a transverse acceleration calculated from a yaw rate of the vehicle (100) and a speed of the vehicle (100), and a detected transverse acceleration of the vehicle (100). The sideslip angle index is related to a sideslip angle of the vehicle (100). The method also comprises a step of generating a control signal (160) using the sideslip angle index. The control signal (160) is suitable for adjusting the roll torque distribution of the roll stabilizer (120) as a function of the determined sideslip angle index.

Claims

1-10. (canceled)

11. A method (300) for stabilizing a vehicle (100), wherein the vehicle (100) comprises a roll stabilizer (120) which is designed to stabilize a first axle (101) and a second axle (102) of the vehicle (100) as a function of a roll torque distribution between the first axle (101) and the second axle (102), and the method (300) comprising: a determination step (310) of determining a sideslip angle index (245) from a difference between a transverse acceleration, calculated from a yaw rate of the vehicle (100) and a speed of the vehicle (100), and a detected transverse acceleration of the vehicle (100), and the sideslip angle index (245) is related to a sideslip angle of the vehicle (100), and a generating step (320) of generating a control signal (160) using the sideslip angle index (245), and the control signal (160) being suitable for adjusting the roll torque distribution of the roll stabilizer (120) as a function of the determined sideslip angle index (245).

12. The method (300) according to claim 11, wherein the control signal (160), produced during the generating step (320), is suitable for adjusting a time variation of the roll torque distribution.

13. The method (300) according to claim 12, wherein the control signal (160), produced during the generating step (320), is suitable for adjusting the time variation of the roll torque distribution in such a manner that, starting from a default value, the time variation increases to a maximum value which is maintained for an adjustable period and then falls back to the default value.

14. The method (300) according to claim 11, wherein the sideslip angle index (245), which corresponds to the sideslip angle and/or to a time variation of the sideslip angle and/or to a variable derived from the sideslip angle, is determined during the determination step (310).

15. The method (300) according to claim 11, further comprising an output step (350) of providing the control signal (160) for output to an interface with the roll stabilizer (120) or to the roll stabilizer (120) and at least one further driving dynamics regulating device (130), and the at least one further driving dynamics regulating device (130) is an active damper device, an active suspension device, a steering device for the first axle and/or the second axle, an axle transverse lock, a dynamic all-wheel drive, a switchable coupling rod, an active ball joint and/or the like.

16. The method (300) according to claim 11, further comprising a calculation step (340) in which the transverse acceleration of the vehicle (100) is calculated as the product of a measured yaw rate of the vehicle (100) and a measured speed of the vehicle (100), in order to provide the calculated transverse acceleration, and the calculated transverse acceleration represents a reference transverse acceleration during a steady-state circular trajectory in which a transverse acceleration, without any sideslip angle, occurs.

17. The method (300) according to claim 11, further comprising a read-in step (330) of reading-in the transverse acceleration of the vehicle (100), from a detection device (108), in order to provide the detected transverse acceleration.

18. A control unit (140), which is designed to carry out and/or control the steps of the method (300), in corresponding units (241, 242, 244, 246, 248), according to claim 11.

19. A system (110) for stabilizing a vehicle (100), wherein the system (110) comprises a roll stabilizer (120) designed to stabilize a first axle (101) and a second axle (102) of the vehicle (100) as a function of a roll torque distribution between the first axle (101) and the second axle (102), and the control unit (140) according to claim 18, wherein the control unit (140) is, or can be, connected to the roll stabilizer (120) for signal transmission purposes.

20. The system (110) according to claim 19, further comprising at least one further driving dynamics regulating device (130), the control unit (140) is, or can be, connected to the at least one further driving dynamics regulating device (130), and the at least one further driving dynamics regulating device (130) is one of: an active damper device, an active suspension device, a steering device for the first axle and/or the second axle, an axle transverse lock, a dynamic all-wheel drive, a switchable coupling rod, an active ball joint and/or the like.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The invention will be explained in greater detail, as an example, with reference to the attached drawings, which show:

[0022] FIG. 1: A schematic representation of a vehicle with a system according to an example embodiment;

[0023] FIG. 2: A schematic representation of the control unit in FIG. 1; and

[0024] FIG. 3: A flow chart of a method for stabilizing, in accordance with an example embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] In the description of preferred example embodiments of the present invention that follows, elements in the various figures that act in similar ways are given the same or similar indexes, so there is no need for a repeated descriptions of those elements.

[0026] FIG. 1 shows a schematic representation of a vehicle 100 with a system 110 for stabilizing the vehicle 100 in accordance with an example embodiment. The vehicle 100 is a motor vehicle for conveying passengers and/or goods, in particular, a passenger car or a utility vehicle. In the vehicle 100, the representation in FIG. 1 shows part of a first axle 101, part of a second axle 102, a first measuring device 104 for measuring a yaw rate of the vehicle 100, a second measuring device 106 for measuring a speed of the vehicle 100 and a detection device 108 for detecting a transverse acceleration of the vehicle 100. The first axle 101 is, for example, a front axle of the vehicle 100. The second axle 102 is, for example, a rear axle of the vehicle 100.

[0027] The first measuring device 104 is designed to measure the yaw rate of the vehicle 100 and to generate a first measurement signal 105 that represents the measured yaw rate. The second measurement device 106 is designed to measure the speed of the vehicle 100 and to generate a second measurement signal 107 that represents the measured speed. The detection device 108 is designed to detect the transverse acceleration of the vehicle 100 and to generate a detection signal 109 that represents the detected transverse acceleration.

[0028] The vehicle 100 also contains the stabilizing system 110. The system 110 comprises a roll stabilizer 120 and a control unit 140. The roll stabilizer 120 is designed, as a function of a roll torque distribution between the first axle 101 and the second axle 102, to stabilize the first axle 101 and the second axle 102 or to bring about a stabilization of the vehicle 100 in respect of the first axle 101 and the second axle 102. In the example embodiment illustrated here, purely as an example, the roll stabilizer 120 comprises a central unit, an axle unit associated with the first axle 101 and an axle unit associated with the second axle 102.

[0029] The control unit 140 is connected with the roll stabilizer 120 for signal transmission purposes. The control unit 140 is designed to control the roll stabilizer 120. More precisely, the control unit 140 is designed, using the first measurement signal 105, the second measurement signal 107 and the detection signal 109, to generate a control signal 160 for controlling the roll stabilizer 120. In this case, the control signal 160 can be transmitted from the control unit 140 to the roll stabilizer 120 via an interface 150. The control signal 160 is appropriate for adjusting the roll torque distribution of the roll stabilizer 120. With reference to the later figures, more details will be given about the control unit 140. For example, the roll stabilizer 120 is designed, using the control signal 160, to adjust the value of the wheel contact forces acting on the wheels of the first axle 101 and the value of the wheel contact forces acting on the wheels of the second axle 102, or designed, using the control signal 160, to adjust a ratio between the wheel contact forces acting on the wheels of the first axle 101 and the wheel contact forces acting on the wheels of the second axle 102.

[0030] According to an example embodiment, the system 110 comprises at least one further drive dynamics regulating device 130. The control unit 140 is connected, for signal transmission, with the at least one further drive dynamics regulating device 130. The control signal 160 from the control unit 140 can also be transmitted to the at least one further drive dynamics regulating device 130, via the interface 150. In the representation in FIG. 1, for reasons of space and only as an example, only one further drive dynamics regulating device 130 is shown. The said at least one further drive dynamics regulating device 130 is, for example, in the form of an active damper device, an active suspension device, a steering device for the first axle 101 and/or for the second axle 102, an axle transverse lock, a dynamic all-wheel drive, a switchable coupling rod, an active ball joint and/or the like. The further drive dynamics, regulating device 130 is designed to use the control signal 160 for adjusting at least one operating parameter of the further drive dynamics regulating device 130. For example, the control signal 160 is used to adjust the damping behavior of a first damping device associated with the first axle 101 and the damping behavior of a second damping device associated with the second axle 102, and/or the spring behavior of a first suspension device associated with the first axle 101 and the spring behavior of a second suspension device associated with the second axle 102. In addition or alternatively, according to an example embodiment, the control signal 160 is used to adjust a drive distribution of an all-wheel drive of the vehicle 100 between the first axle 101 and the second axle 102. By virtue of such measures, the drive dynamics of the vehicle 100 can be additionally optimized.

[0031] In an example embodiment, the roll stabilizer 120, which is also referred to as the electric or electro-mechanical roll stabilizer (ERC), is designed to displace a roll torque dynamically between the first axle 101 and the second axle 102. Thereby, wheel contact forces, between the wheels of the first axle 101 and the second axle 102, are displaced in a defined manner, so that the yaw behavior of the vehicle 100 can be influenced. For this, the displacement of the wheel contact forces is carried out using the control signal 160.

[0032] According to an example embodiment, the transverse acceleration is calculated using the measured yaw rate and the speed of the vehicle for the stabilization of the vehicle 100. Here, the transverse acceleration is calculated as the product of the measured yaw rate and the measured speed. This relation is valid for a steady-state circular trajectory of the vehicle 100, without any sideslip angle. Thus, a discrepancy of the said relation describes the sideslip angle. The said discrepancy is determined by a deviation between the calculated transverse acceleration and the detected transverse acceleration, i.e., for example between a calculated signal described with reference to FIG. 2 and the detected signal 109, and serves as a sideslip angle index. Depending on the sideslip angle index, the roll torque distribution is displaces by a correspondingly generated control signal 160. To stabilize the vehicle 100 in a robust manner, according to an example embodiment, a variation of the control signal 160 follows a so-termed “peak-hold and ramp-down” function. This maintains a peak value for an appropriate period and then falls back to an original value. The peak value can be a fixed specified maximum value or an actually reached maximum value. The original value can be a default value specified for an operating mode of the vehicle 100.

[0033] According to an example embodiment, the control signal 160 can also be sent only to the at least one further drive dynamics regulating device 130. In that case, no roll torque distribution is carried out.

[0034] FIG. 2 shows a schematic representation of the control unit 140, in FIG. 1, according to an example embodiment. In particular, the control unit 140 is designed to carry out the method described with reference to FIG. 3 or a similar method. The control unit 140 has a determining device 244 and a generating device 246. According to the example embodiment illustrated here, the control unit 140 optionally also has a reading-in device 241, a calculating device 242 and an output device 248.

[0035] The reading-in device 241 is designed to read in the detection signal 109 that represents the transverse acceleration of the vehicle from the detection device. The reading-in device 241 is also designed to read in the first measurement signal 105 that represents the measured yaw rate of the vehicle and the second measurement signal 107 that represents the measured speed of the vehicle. In addition, the reading-in device 214 is designed to pass on the first measurement signal 105 and the second measurement signal 107 to the calculating device 242. Moreover, the reading-in device 214 is designed to pass on the detection signal 109 to the determining device 244.

[0036] The calculating device 242 is designed, using the first measurement signal 105 and the second measurement signal 107 and a calculation protocol, to generate a calculation signal 243 that represents the calculated transverse acceleration of the vehicle. Otherwise expressed, the calculating device 242 is designed to calculate the transverse acceleration of the vehicle as the product of the measured yaw rate of the vehicle and the measured speed of the vehicle, in order to obtain the calculated transverse acceleration represented by the calculated signal 243.

[0037] The calculated transverse acceleration represents a reference transverse acceleration during a steady-state circular trajectory without the occurrence of any sideslip angle. The calculating device 242 is also designed to pass the calculated signal 243 on to the determining device 244.

[0038] The determining device 244 is designed, using the detection signal 109 and the calculation signal 243 as well as a determination protocol, to determine a sideslip angle index 245. Otherwise expressed, the determining device 244 is designed to determine the sideslip angle index 245 from a difference between a transverse acceleration of the vehicle calculated from a deviation between a yaw rate of the vehicle and a speed of the vehicle, and a detected transverse acceleration of the vehicle. The sideslip angle index 245 stands in a relationship, in particular a known or defined relationship, with a sideslip angle of the vehicle. The determining device 244 is designed to send the sideslip angle index 245 to the generating device 246 or to prepare it for sending thereto.

[0039] The generating device 246 is designed, using the sideslip angle index 245, to generate the control signal 160. The control signal 160 is suitable for adjusting the roll torque distribution of the roll stabilizer as a function of the determined sideslip angle index 245. The generating device 246 is also designed to pass the control signal 160 onto the output device 248.

[0040] The output device 248 is designed to prepare the control signal 160 for output to the interface 150 with the roll stabilizer or with the at least one further driving dynamics regulating device. Thus, the control signal 160 can be used in the roll stabilizer to adjust the roll torque distribution to be brought about by the roll stabilizer. In addition or alternatively, the control signal can be used by the further driving dynamics regulating device to adjust at least one driving dynamics regulation parameter to be carried out by the further driving dynamics regulating device.

[0041] FIG. 3 shows a flow chart of a stabilizing method 300, according to an example embodiment. The method 300 can be carried out in order to stabilize a vehicle. In this case, the stabilization method 300 can be carried out in combination with a roll stabilizer designed to stabilize a first axle and a second axle of the vehicle as a function of a roll torque distribution between the said first and second axles. The stabilizing method 300 can be carried out using the control unit in one of the above-described figures or a similar control unit.

[0042] The stabilizing method 300 comprises a step 310 of determining a sideslip angle index from a deviation between a transverse acceleration of the vehicle, calculated from a yaw rate of the vehicle and a speed of the vehicle, and a detected transverse acceleration of the vehicle. In this, the sideslip angle index is related to a sideslip angle of the vehicle. According to an example embodiment, in the determination step 310, a sideslip angle index is determined, which corresponds to the sideslip angle index and/or which corresponds to a time variation of the sideslip angle and/or which is a variable derived from the sideslip angle.

[0043] The stabilizing method 300 also comprises a step 320 of generating a control signal, using the determined sideslip angle index from the determining step 310. The control signal is suitable for adjusting the roll torque distribution of the roll stabilizer as a function of the determined sideslip angle index. In an example embodiment, the control signal produced in the generating step 320 is suitable for adjusting a variation of the roll torque distribution in such a manner that, starting from a default value, the variation increases to a maximum value which is held for an adjustable period, and which then decreases back to the default value.

[0044] According to an example embodiment, the stabilizing method 300 also comprises a reading-in step 330 and/or a calculation step 340 and/or an output step 350. In this, the reading-in step 330 and the calculation step 340 can be carried out before the determination step 310. The output step 350 can be carried out after the generation step 320.

[0045] In the reading-in step 330, the transverse acceleration of the vehicle is read in from a detection device in order to provide the detected transverse acceleration. Optionally, in the reading-in step 330, a measured yaw rate of the vehicle and a measured speed of the vehicle are also read in from measurement devices in the vehicle.

[0046] In the calculation step 340, the transverse acceleration of the vehicle is calculated as the product of a measured yaw rate of the vehicle and a measured speed of the vehicle in order to obtain the calculated transverse acceleration. Here, the calculated transverse acceleration represents a reference transverse acceleration during a steady-state circular trajectory without the occurrence of a sideslip angle.

[0047] In the output step 350, the control signal produced in the generating step 320 is sent for output to an interface with the roll stabilizer and in addition or alternatively with at least one further driving dynamics regulating device. The at least one further driving dynamics regulating device is an active damper device, an active suspension device, a steering device for the first axle and/or the second axle, an axle transverse lock, a dynamic all-wheel drive, a switchable coupling rod, an active ball joint and/or the like.

[0048] In an optional step 360, the control signal is used for regulating the driving dynamics of the vehicle. According to an example embodiment, the control signal is used by the roll stabilizer to adjust the roll torque distribution. In addition or alternatively, the control signal is used by the at least one further driving dynamics regulating device to adjust at least one parameter of the at least one further driving dynamics regulating device.

[0049] When an example embodiment contains an “and/or” link between a first feature and a second feature, then this can be read to mean that the example embodiment in one form allows both the first and the second feature, and, in another form, allows either only the first feature or only the second feature.

INDEXES

[0050] 100 Vehicle [0051] 101 First axle [0052] 102 Second axle [0053] 104 First measuring device [0054] 105 First measurement signal [0055] 106 Second measuring device [0056] 107 Second measurement signal [0057] 108 Detection device [0058] 109 Detection signal [0059] 110 Stabilization system [0060] 120 Roll stabilizer [0061] 130 Further driving dynamics regulating device [0062] 140 Control unit [0063] 150 Interface [0064] 160 Control signal [0065] 241 Reading-in device [0066] 242 Calculation device [0067] 243 Calculation signal [0068] 244 Determination device [0069] 245 Sideslip angle index [0070] 246 Generating device [0071] 248 Output device [0072] 300 Stabilization method [0073] 310 Determination step [0074] 320 Generating step [0075] 330 Reading-in step [0076] 340 Calculation step [0077] 350 Output step [0078] 360 Application step