Method for reducing steering torque in a steering system of a vehicle

Abstract

A method for reducing the steering torque in a steering system of a vehicle. A method including the steps of monitoring a driver's torque as applied by a driver of the vehicle; providing a plurality of torques that can be imposed on the steering system; and reducing the torques that can be imposed on the steering system by a central reduction factor if monitoring of the steering system reveals a violation of a safety criterion.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Not Applicable.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention relates to vehicle steering systems and, more specifically, to a method for controlling or reducing steering torque in a steering system of a vehicle.[0004]2. Description of Related Art[0005]Modern steering systems include assistance systems that enable the imposition of steering torque in order to provide driver comfort. Moreover, such assistance systems operate to reduce disturbing torque influences caused by the vehicle or the surface of the highway.[0006]The steering wheel is the haptic interface to the driver and any imposed torque must be configured whereby it can be controlled by the driver. For example, in the event of a fault, such as an unintentional imposed torque, the driver's reaction remains an important non-negligible part of the overall system.[0007]Consideration of the impact of unfavorable torque impositions on the overall steeri...

AI Technical Summary

Benefits of technology

The patent is about a method to reduce the torque applied to a system or a vehicle. The method uses a reduction factor that prevents oscillations in the torque during changes or continuous flow of the method. The reduction factor can be applied individually to each torque or combined torches can be reduced using the factor. This allows for optimal adaptation to different situations or vehicles. The technical effect of the method is to provide a more efficient and flexible way to control the torque applied to a system or vehicle.

Problems solved by technology

Normally, the steering torque superimposed on the driver's torque by such assistance systems is limited in amplitude and dynamics.

This means that the potential performance of additional functions or torque impositions cannot always demand torque useful or necessary for the respective situation.

This means that all limiting additional functions for providing the additional torque in the control loop have to calculate / determine the corresponding driver's torque.

The calculation of the driver's torque is complex on the one hand and can frequently only be carried out roughly because of the complexity of the control loop.

This can lead to loss of quality of the respective functions.

A combined limitation of the output torque and of the driver's torque is in general not possible, because both torques are not necessarily linearly dependent.

This means that it will only be limited if the imposed torque leads to a corresponding critical vehicle reaction in the driver / vehicle / situation composite.

This is complex depending on the complexity of the steering control loop and can cause delays and inaccuracies.

The quality of the additional steering functions can degrade because of this.

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