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Electric power steering systems (EPS) are characterized by high inertia and therefore by a considerably damped transmission behaviour. While this is desirable for comfort-oriented designs, EPS do not provide enough feedback of the driving conditions, especially for drivers with a sporty driving style. The systematic actuation of the electric motor of an EPS makes it possible to specifically increment the intensity of the response. In this context, the road-sided induced forces of the tie rod and the steering rack force provide all the information for the steering system’s response. Former concepts differentiate between use and disturbance information by defining frequency ranges. Since these ranges overlap strongly, this differentiation does not segment distinctively. The presented article describes a method to identify useful information in the feedback path of the steering system depending on the driving situation.

A new approach to improve the driver's safety is to actively support the driving task and prevent possibly dangerous situations. This paper is about the family of driver assistance systems which will combine three steps of information processing: Automatic collection of data by scanning the environment of the vehicle; Automatic processing of data according to the need of the driver and his driving task; Appropriate presentation of valuable information to the driver. Electronic sensor systems will enlarge the driver's knowledge about what is actually going on around his vehicle. These systems expand the human sensor systems eye and ear for the special purpose "safe driving."

New technologies such as multi-core and Ethernet provide vastly improved computing and communications capabilities. This sets the foundation for the implementation of new digital megatrends in almost all areas: driver assistance, vehicle dynamics, electrification, safety, connectivity, autonomous driving. The new challenge: We must share these computing and communication capacities among all vehicle functions and their software. For this step, we need a good resource planning to minimize the probability of late resource bottlenecks (e.g. overload, lack of real-time capability, quality loss). In this article, we summarize the status quo in the field of resource management and provide an outlook on the challenges ahead.

Electromechanical steering systems (EPS) provide assisting steering force through an electric motor, often paired with a screw drive. The combination of an electric motor and a screw drive lead to high inertia and thus to a reduced feedback of tire force behavior at the steering wheel. This force behavior contains information about driving conditions and road surface. However, the electric motor can be used to actively enhance and manipulate steering feedback. This article describes the driver perception of modified steering feedback. The presented data is collected carrying out a driving simulator study with average drivers as test subjects. In this study the driver experiences a modified steering feedback at a change of road friction coefficient. Based on the test subjects ratings the perception, acceptance and controllability of the presented steering feedback modifications are assessed.

In steer-by-wire (SbW) vehicles, understanding the steering rack force is essential to replicate a realistic steering feel, allowing conclusions to be drawn about road surface conditions by the decoupled manual actuator. Since internal friction varies with each steering system manufactured and installed, these models differ greatly in accuracy. This paper presents a concept for continuously calculating fluctuating friction based on the internal steering variables to avoid additional and complex individual measurements. An SbW system offers the right approach by adjusting the driver’s desired steering angle and the required motor control. The underlying steering clearance and the Kalman filter are used to calculate the steering rack force. The validity of the proposed concept is shown in drive tests according to ISO 13674 and ISO 7401 to gauge high and low friction values in different speed ranges.