Method and device for influencing the driving position of a motor vehicle

Abstract

Method for influencing the driving position of a motor vehicle by means of at least one active component (3, 4) for compensating roll moments, wherein the component (3, 4) can be deactivated automatically or manually, wherein the motor vehicle has an off-road mode, wherein the off-road mode can be set automatically or manually, wherein in the off-road mode the active component (3, 4) is deactivated, and wherein in the deactivated state of the active component (3, 4) the active component (3, 4) is manually activated and set.

Description

[0001] The invention relates to a method and a device for influencing the driving position of a motor vehicle by means of at least one active component for compensating for roll moments.

[0002] Various devices are known for influencing the driving position or chassis of a motor vehicle in order to stabilize the vehicle. The most well-known component is the stabilizer bar, which connects the two wheels of an axle to each other and to the body structure. Motor vehicles have at least one stabilizer bar on the front axle, and often one is also fitted to the rear axle. The stabilizer bar works as follows: When a motor vehicle travels through a right-hand curve, its body is pushed to the left by centrifugal force. The outer wheels compress their suspension, while the inner wheels extend. The motor vehicle begins to lean. The stabilizer bar prevents this lean by distributing the forces between the wheels so that they compress and extend as evenly as possible. This keeps the body roll under control.Active stabilizers are used particularly in larger vehicles and SUVs. These typically operate with a motor that adjusts the stabilizer bar's metal rod. This allows the stabilizer to be set to a softer setting for straight-line driving and a stiffer setting for cornering. On extremely uneven terrain, the uniform compression of both wheels is undesirable, as this can cause one tire to lift off the ground, resulting in a loss of traction. Therefore, in high-end vehicles with an off-road mode, the stabilizers can be deactivated. At the push of a button, a clutch opens, allowing the two halves of the metal rod to move independently.

[0003] Alternatively, active stabilizer links are known, in which the connection between a stabilizer bar and a control arm is controllable. These active stabilizer links also serve to compensate for roll moments.

[0004] Furthermore, an electro-hydraulic active suspension system based on steel springs is known, also under the brand name Active Body Control. In addition to its suspension and damping functions, this system compensates for the vehicle's pitch and roll movements. Because the hydraulic system levels the vehicle, such vehicles do not require conventional stabilizers. To perform these functions, each strut contains a vertically adjustable, single-acting hydraulic cylinder that continuously regulates the respective spring preload.

[0005] From EP 1 466 763 B1, a method for operating a level control system of a motor vehicle is known, comprising a control device, sensors for directly or indirectly determining the distance between the vehicle body and the axles of the vehicle wheels, and actuators for adjusting the distance between the vehicle body and these wheel axles. Based on the measured values, the control device performs a target-actual comparison to check whether the distances between the vehicle body and the wheel axles exceed predetermined limits. If there is a deviation from these limits, one or more of the actuators are activated to achieve leveling by aligning the vehicle body horizontally. The control device disables the automatic leveling control if the vehicle is in a tilted or uneven position that is unacceptable for vehicle safety.Furthermore, the control unit is designed to allow manual activation of the actuators on the wheel axles after the automatic leveling procedure has ended. Preferably, the control unit recommends to the driver, via a display or voice output, which of the affected actuators should be activated and how, according to the control unit's assessment, in order to bring the vehicle body into a more comfortable and / or safer position despite the detected impermissible slope and tilt. This control process can also be carried out automatically, with or without prior authorization by the driver, axle by axle or wheel by wheel (manually or automatically triggered slope stabilization).

[0006] DE 10 2005 009 002 A1 discloses a method for operating active stabilizers on motor vehicles. It comprises an on-road mode in which a stabilizer is activated and deactivated depending on operating parameters of the motor vehicle, in particular the vehicle speed and / or lateral acceleration and / or a level sensor. In the activated state, roll movements of the vehicle are reduced by introducing counteracting torques into the stabilizer(s). The method also includes an off-road mode in which the stabilizer is deactivated up to a defined vehicle speed, or, in the case of alternating compression of the suspension, the stabilizer is activated by increasing the contact force of the extending wheel. Furthermore, the method proposes incorporating wheel slip into the control of the stabilizers. A suitably configured motor vehicle is also claimed.

[0007] The invention is based on the technical problem of creating a method and a device for influencing the driving position of a motor vehicle, by means of which improved driving behavior can be achieved.

[0008] The solution to the technical problem is achieved by the objects having the features of claims 1 and 5. Further advantageous embodiments of the invention are set forth in the dependent claims.

[0009] For this purpose, the driving position or chassis of a motor vehicle is influenced by means of at least one active component to compensate for roll moments, wherein the component can be deactivated automatically or manually, wherein the motor vehicle has an off-road mode, wherein the off-road mode The active component is automatically or manually adjustable, with the active component being deactivated in off-road mode and manually activated and adjusted in the deactivated state. This is based on the understanding that situations can arise when the active component is deactivated, where the chassis's position can be improved by temporarily activating and adjusting the active component. For example, if the active component is deactivated and the right front wheel experiences significant compression, the left rear wheel may lift off the ground, potentially leading to a loss of traction. According to the invention, the active component can now be manually activated and adjusted. If the active component is, for example, an active stabilizer, the wheel load can be changed axle by axle.In the example shown, the wheel load on the right front wheel is increased, causing the front of the body to lift. This causes the left rear wheel to lower and regain traction.

[0010] The advantage of active components for compensating roll moments compared to level control systems is that they are effective within seconds or faster, whereas level control systems are considerably slower. A suitable human-machine interface is required for manual activation and adjustment of the active component. It should be noted that manual activation and adjustment can also be performed via voice command. Furthermore, it can be provided that manual activation is automatically deactivated after a few seconds. It is also possible to provide the driver with adjustment recommendations.

[0011] The automatic setting of the off-road mode can be based, for example, on data from various sensors. Manual setting is preferably achieved via a control element, such as a push-button switch. This manual control element can also be used to manually activate the active component, for example, by temporarily deactivating the off-road mode. However, it is preferable that the controls are implemented separately to improve clarity.

[0012] In one embodiment, the active component is designed as an active stabilizer, preferably with one active stabilizer assigned to each wheel axle. In an alternative embodiment, the active component is designed as an active connecting rod, which is also preferably present on both axles. In a further alternative embodiment, the active component is designed as an electro-hydraulic active vehicle system based on a steel spring suspension.

[0013] In another embodiment, the motor vehicle additionally has a level control system, wherein the level control system can also be manually activated and adjusted in order to better adapt the vehicle position to the situation.

[0014] In another embodiment, the manual adjustment of the active component and / or the level control system is limited on the vehicle side to prevent vehicle stability from no longer being guaranteed.

[0015] The invention is explained in more detail below with reference to a preferred embodiment. The single figure shows a schematic block diagram of a device for influencing the vehicle position of a motor vehicle.

[0016] The device 1 comprises a central control unit 2, a first active component 3, and a second active component 4 for compensating roll moments. The first active component 3 includes an electric motor 3a and two stabilizer bars 3b, 3c. The first stabilizer bar 3b is located between the left front wheel LV and the electric motor 3a. Similarly, the second stabilizer bar 3c is located between the right front wheel RV and the electric motor 3a. The left front wheel LV and the right front wheel RV are connected to each other via a front axle VA. Similarly, a left rear wheel LH ​​and a right rear wheel RH are connected to each other via a rear axle HA. The active component 4 also includes an electric motor 4a and two stabilizer bars 4b, 4c. Furthermore, the device 1 includes a level control system, which, for example, comprises four air springs 5a-5d.Finally, the device 1 also has a human-machine interface 6, which is designed as an input and output unit. The human-machine interface 6 has an off-road button 7, an activation button 8, and an input element 9.

[0017] In normal conditions on level roads, the active components 3, 4 and the air springs 5a-5d are active and are controlled by the control unit 2 depending on sensor signals.

[0018] If the driver wishes to drive off-road, he confirms the off-road button 7. In response, the control unit 2 deactivates the active components 3, 4 and the level control system, whereby, for example, a specific level is set and fixed using the air springs 5a-5d.

[0019] In certain situations, the driver can now manually activate the active components in off-road mode using activation button 8 and adjust them manually using input element 9. Possible inputs include, for example, the stabilizer torques of active components 3 and 4 to change the wheel load on each axle. This allows the vehicle's attitude to be changed situationally, as a change in wheel load alters the compression and rebound of the suspension. A change on one axle due to compression or rebound also affects the attitude of the other axle. Since active components 3 and 4 may be more of a hindrance after positively influencing the vehicle's attitude, they are deactivated again after a predetermined time. Alternatively, the driver must deactivate active components 3 and 4 manually.

Claims

[1] Method for influencing the driving position of a motor vehicle by means of at least one active component (3, 4) for compensating roll moments, wherein the component (3, 4) can be deactivated automatically or manually, wherein the motor vehicle has an off-road mode, wherein the off-road mode can be set automatically or manually, wherein in the off-road mode the active component (3, 4) is deactivated, and wherein in the deactivated state of the active component (3, 4) the active component (3, 4) is manually activated and set. [2] Method according to claim 1, characterized by e that the active component (3, 4) is designed as an active stabilizer or as an active connecting rod or as an electro-hydraulic active suspension system based on a steel spring. [3] Method according to any of the preceding claims, characterized by, that the vehicle additionally has a level control system, whereby the level control system is also manually activated and adjusted. [4] Method according to any of the preceding claims, characterized by , that the manual adjustment of the active components (3, 4) and / or the level control system is limited on the vehicle side. [5] Device (1) for influencing the driving position of a motor vehicle, comprising at least one active component (3, 4) for compensating roll moments, wherein the component (3, 4) can be deactivated automatically or manually, wherein the motor vehicle has an off-road mode, wherein the off-road mode can be set automatically or manually, wherein in the off-road mode the active component (3, 4) is deactivated, wherein in the deactivated state of the active component (3, 4) the active component (3, 4) can be activated and set manually. [6] Device according to claim 5, characterized by, that the active component (3, 4) is designed as an active stabilizer or as an active connecting rod or as an electro-hydraulic active suspension system based on a steel spring. [7] Device according to one of claims 5 or 6, characterized by that the vehicle additionally has a level control system which can also be manually activated and adjusted. [8] Device according to any one of claims 5 to 7, characterized by , that the manual adjustment of the active component (3, 4) and / or the level control system is limited on the vehicle side.

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