METHOD AND ADJUSTMENT SYSTEM FOR KEEPING A VEHICLE ON COURSE DURING ROLL MOVEMENTS OF A VEHICLE BODY

Abstract

A method for keeping a vehicle on course by determining a lateral acceleration of the vehicle; establishing a desired lateral inclination of the vehicle depending on the lateral acceleration determined in step a); adjustment of at least one actuator of an active chassis device of the vehicle, so the vehicle takes on the desired lateral inclination determined in step b); and c) carrying out a compensatory engagement by adjustment of at least one actuator of an active chassis device of the vehicle, so the vehicle takes on the desired lateral inclination determined in step b), wherein, in step d), at least one additional compensatory engagement is carried out by an additional active chassis device for the at least partial compensation of a yaw movement of the vehicle caused by the adjustment of the at least one actuator of the active chassis device.

Claims

1. A method for keeping a vehicle on course comprising the following steps: a) determining a lateral acceleration of the vehicle: b) establishing a desired lateral inclination of the vehicle depending on the lateral acceleration determined in step a); c) carrying out a compensatory engagement by adjustment of at least one actuator of an active chassis device of the vehicle, so that the vehicle takes on the desired lateral inclination determined in step b), wherein in that, d), at least one additional compensatory engagement is carried out by means of an additional active chassis device for at least partial compensation of a yaw movement of the vehicle caused by the adjustment of the at least one actuator of the active chassis device.

2. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out synchronously in time with carrying out step c).

3. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out based on an adjustment between a yaw rate measured using at least one sensor and a yaw rate that is specified by a driver of the vehicle and is defined by the drive trajectory.

4. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver of an active superimposed steering system or by way of a steering maneuver of an active superimposed steering system and simultaneous steering operation at a rack of an electrical power steering (EPS).

5. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rack of an electrical power steering (EPS).

6. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver and/or a camber change at a twin tandem wheel bearing.

7. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rear-axle steering or by means of a differential torque at the superimposed differential of a rear axle and/or front axle of the vehicle.

8. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out by way of a differential torque with torque vectoring function or braking torque vectoring function at an electric motor of a rear axle and/or front axle of the vehicle and simultaneous increase in a drive force.

9. The method according to claim 1, wherein in that the at least one additional compensatory engagement is carried out through a tensioning between a front and a rear axle of the vehicle due to shifting a roll movement distribution of an active roll stabilization or of an eABC system.

10. An adjustment system for carrying out a method according to claim 1, comprising: a measuring device for determination of the lateral acceleration and an actuator for carrying out a compensatory engagement of an active chassis device of a vehicle, wherein in that the adjustment system comprises at least one additional active chassis component, which is designed for at least partial compensation of a yaw movement caused by the adjustment of the at least one actuator of the active chassis device.

11. The adjustment system according to claim 10, wherein in that the at least one additional active chassis component is designed as an active front-axle steering, a rear-axle steering, a twin tandem wheel bearing, a superimposed differential, or an electric torque device, or a combination thereof.

12. The method according to claim 2, wherein in that the at least one additional compensatory engagement is carried out based on an adjustment between a yaw rate measured using at least one sensor and a yaw rate that is specified by a driver of the vehicle and is defined by the drive trajectory.

13. The method according to claim 2, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver of an active superimposed steering system or by way of a steering maneuver of an active superimposed steering system and simultaneous steering operation at a rack of an electrical power steering (EPS).

14. The method according to claim 3, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver of an active superimposed steering system or by way of a steering maneuver of an active superimposed steering system and simultaneous steering operation at a rack of an electrical power steering (EPS).

15. The method according to claim 2, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rack of an electrical power steering (EPS).

16. The method according to claim 3, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rack of an electrical power steering (EPS).

17. The method according to claim 2, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver and/or a camber change at a twin tandem wheel bearing.

18. The method according to claim 3, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver and/or a camber change at a twin tandem wheel bearing.

19. The method according to claim 2, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rear-axle steering or by means of a differential torque at the superimposed differential of a rear axle and/or front axle of the vehicle.

20. The method according to claim 3, wherein in that the at least one additional compensatory engagement is carried out by way of a steering maneuver at a rear-axle steering or by means of a differential torque at the superimposed differential of a rear axle and/or front axle of the vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0031] The method and the adjustment system for keeping a vehicle on course during a roll movement of a vehicle body will be illustrated schematically on the basis of implementation embodiments and will be described schematically and in detail with reference to the drawing.

[0032] FIG. 1 shows a schematic flowchart for carrying out the method for keeping a vehicle on course during a roll movement of a vehicle body.

DETAILED DESCRIPTION

[0033] FIG. 1 shows a schematic flow chart for carrying out the method according to the invention for keeping a vehicle on course during a roll movement of a vehicle body.

[0034] In a first step a), a lateral acceleration of the vehicle is determined in this case, with this determination preferably being performed by a measuring devicenot shown in FIG. 1so that a currently prevailing lateral acceleration is determined.

[0035] In a second step b), a lateral inclination of the vehicle is established depending on the lateral acceleration established in step a). Such a lateral acceleration occurs during a lateral inclination of a vehicle. The lateral inclination is understood, in particular, to mean a rotation of the vehicle around its roll axis. Such rotational movements occur, in particular, during cornering of the vehicle, when lateral accelerations bring about a rotation or an inclination of the vehicle on account of the centrifugal force. The desired lateral inclination established in step b) is adjusted in such a way that, during a rotation of the vehicle and its roll axis, a drive feel that is as comfortable as possible and mostly undisturbeding results for the occupants of the vehicle.

[0036] In a third step c), a compensatory engagement is carried out through the adjustment of at least one actuator of an active chassis device of the vehicle, so that the vehicle carries out the desired lateral inclination determined in step b). The actuators used in step c) are preferably electrohydraulic setting devices, which engage at the individual wheels of the vehicle and control the vertical position thereof. The active chassis device can be an active suspension system, such as, for example, an active body control system, and/or a system with active roll stabilizers, such as, for example, an eARS. The individual actuators of the respective wheels can be controlled, in particular, in such a way that only specific wheels are raised or lowered, so that the specified desired lateral inclination of the vehicle is adjusted. The actively induced roll of the vehicle contributes to an improvement in the driving comfort feel of the vehicle occupants, as a result of which a necessary counter steering movement on the part of the driver can be reduced.

[0037] In accordance with the invention, in a step d) at least one additional compensatory engagement is carried out by means of a another active chassis device for at least partial compensation of a yaw movement of the vehicle caused by adjustment of the at least one actuator of the active chassis device. Carrying out step d) makes possible a tracking precision of the vehicle itself in the case of a roll movement during cornering. In this way, an undesired yaw response and slide-slip response of the vehicle, which, under certain circumstances, the driver would have to compensate with an uncomfortable steering maneuver, is counteracted. Accordingly, by way of the additional compensatory engagement, the drive feel of the vehicle occupants is improved, because the effects of any roll movement of the vehicle that are felt are further reduced. In this way, the driving comfort is increased and the driving behavior is more secure and more agile. In this case, the at least one additional compensatory engagement is based on a compensation between a yaw rate that is measured using at least one sensor and a yaw rate that is specified by a driver of the vehicle and is defined by the drive trajectory. Step d) in accordance with the invention takes place preferably synchronously in time with step c).

[0038] The compensatory engagement is preferably carried out by means of at least one additional active chassis component, which is preferably designed as an active front-axle steering, a rear-axle steering, a twin-tandem wheel bearing, a superimposed differential, or an electric torque device, or as a combination thereof.