Domain controller concept gains traction

September 02, 2015 // By Christoph Hammerschmidt
Automotive supplier ZF TRW has won two business contracts for the second generation of its Safety Domain ECUs. The orders come from a European and a North American OEM, respectively. Is this a hint that the domain controller will prevail?

The Safety Domain ECU with the type designation SDE2 acts as a central integration hub that brings together multiple data sources from environmental sensors of the vehicle’s state and its surroundings. Interfacing with steering, powertrain and braking systems, the controller can enable a host of functions. At the same time, it reduces the number of disparate control units across the vehicle and thus simplifies the vehicle’s electronic architecture.

The concept of a domain controller that replaces multiple dedicated ECUs can be regarded as alternative to the widespread approach of adding a dedicated ECU for each and every new feature and task within the car. This approach leads to a widely uncontrolled proliferation of ECUs and thus to an increased complexity of the electronics landscape under the hood. Experts such as consulting company Roland Berger have already warned that this complexity is reaching a tipping point and may render unforeseeable difficulties. However, designers from throughout the industry, in particular from carmaker BMW, are advocating a concept that potentially can greatly reduce the complexity by combining the functionality of multiple ECUs within one powerful domain controller. Such concepts are possible since over the past couple of years more powerful processors have become available that can handle multiple tasks. Basically, the concept shifts the processing level from the hardware to software. Here, techniques such as virtualisation enable the safe and secure separation of computing tasks –even if one virtual controller crashes, the other controllers work on unaffectedly.

This approach has also been implemented in TRW’s Safety Domain Controller. Hans-Gerd Krekels, director of Active Safety Engineering and Automated Driving at ZF TRW comments: “Data processing is at the core of automated driving and as vehicles feature more automated functions, increasing amounts of information about the vehicle’s surroundings need to be evaluated within fractions of a second. This requires a high performance control unit.”

The SDE2 fulfills the highest Automotive Safety Integrity Level – (ASIL D) requirements which actively monitor braking and steering systems and actuate selected functions when necessary. Compared to the previous generation, the unit can also integrate more data from vehicle dynamics arbitration systems and sensors – including radar and camera – to help enable 360° environmental sensing.