A classic servo steering system uses a continuously driven pump. It provides constant pressure, regardless of whether the steering wheel is being turned or not. This principle has proven itself over decades and provides direct feedback to the driver. Electrohydraulic steering goes one step further. Here, an electric unit controls the hydraulic pump as needed. 
 

Energy consumption is reduced for several reasons:

1. because the system only supplies (electrical) power when a steering movement occurs.
2. because no additional steering valves are required, which have a constant power consumption of their own and thus reduce the efficiency of the overall system.

If you're wondering how electrohydraulic steering works, the answer lies in the combination of electronic control and hydraulic power transmission. The system combines precise signal processing with robust hydraulic technology.
 

2. Steering system design and technical integration

The steering system comprises a steering unit, valve technology, hydraulic cylinders, lines, and sensors. At its heart is the control valve. It distributes the volume flow depending on the steering angle and generates the necessary pressure difference in the working cylinder. In complex vehicles, simple front-axle steering is not sufficient. 
 

Steering systems for modern mobility, special vehicles, or construction machinery integrate additional axles, electronic monitoring, and safety-related functions. The topic of steer-by-wire systems is also gaining importance here. A steer-by-wire steering system does not require a continuous mechanical connection between the steering wheel and the axle. Instead, an electronic unit transmits the steering commands. Hydraulic actuators convert these signals and continue to ensure high forces.

Road vehicles have different requirements than off-road machines. Stability is important at high speeds. Off-road, maneuverability is the priority. Hydraulic steering systems can be adapted to both scenarios. In heavy-duty machines, hydraulic steering provides reliable control even under extreme conditions. An electro-hydraulic system is superior to mechanical solutions, particularly in the case of varying loads, vibrations and/or dusty environments. For mobile applications with variable axle configurations, WEBER-HYDRAULIK develops modular solutions that can be integrated into different vehicle concepts. The demand for precise hydraulic support is also growing in the field of modern steer-by-wire vehicles. Electronic control units calculate the optimum steering angle, while hydraulic actuators provide the necessary force. The result is a system that combines dynamics and control. 
 

4 Cyber Security (CySec) and Functional Safety (FuSa) in modern steering systems

With the increasing electrification and connectivity of modern vehicles, the safety requirements for steering systems are also rising. In addition to classic functional safety, cyber security is becoming particularly important. Both areas are crucial to ensuring that safety-critical functions such as vehicle steering work reliably and are protected against unauthorized access at the same time.
 

4.1 Functional safety in steering systems

Functional safety describes the ability of a system to ensure a safe state even in the event of errors. In the automotive industry, the international standard ISO 26262 is authoritative in this regard. It defines processes, methods, and requirements for the development of safety-related electrical and electronic systems.
 

4.2 Cyber Security in Networked Vehicle Architectures

In addition to functional malfunctions, modern steering systems must also be protected against cyber attacks. Networked vehicle architectures, over-the-air updates, and interfaces to driver assistance systems create new potential points of attack.