CARIAD, a unified software architecture for the entire Volkswagen Group
Today, car functions are controlled by dedicated ECUs, each in turn uses its own software. In the near future, however, they will all be managed through one central software, which will make updates easier and support functions for highly automated driving with machine learning and AI.
Today, cars are already computers on wheels: they assist drivers with steering, braking and keeping the right distance, they connect them to the Internet and, in the case of electric vehicles, can automatically process payments at charging stations.
In a traditional electronics architecture, all these functions are not controlled by a central computer, but rather managed by a large number of control units (over 100) located in various areas of the vehicle. All of these control units are connected to sensors and actuators - such as cameras, radar, lidar - and designed to perform specific tasks. In many cases a single function is linked to a single control unit which in turn uses it own software for this purpose; as a result, vehicles are becoming increasingly complex, and such an architecture is reaching its limits.
Innovative design
That’s why CARIAD is developing a unified architecture that will be used by the entire Volkswagen Group in the near future. It is a highly innovative project that will be the basis for all vehicles developed from software and will mark a turning point: the car will become a true digital device, a smart companion for its drivers.
"The standardized architecture is the key to unlocking new vehicle functions at lightning speed in the future with an over-the-air update, and to enabling highly automated driving at Level 4 with machine learning and artificial intelligence", explains Alf Pollex, who heads the development network for the Group-wide standardized software platform at CARIAD.

Traditional architecture: the ECUs
In a vehicle with a traditional electronics architecture, all control units and software communicate with each other to keep the infotainment system and driver assistance functions operating, settings such as seat position adjustment, and more. Tasks are clearly defined: each sensor or actuator is connected to its own "technology package," which includes hardware, software and electronic control unit, and is independently responsible for carrying out its functions. Information from the various sensors converges via a central gateway that serves as a communication node. From there they are then forwarded where needed, for example to the infotainment system. "A new function always brings with it a new control unit", Alf resumes.
From ECUs to the server
One of the main disadvantages of such a decentralized architecture is obvious: if one of the software functions has a problem or needs to be updated, taking action is very complicated, especially when a system uses several sensors, such as parking assistance that uses a front and a rear camera. In this case, the software update involves several ECUs, which is very time-consuming.
Based on this, CARIAD has already launched a new software platform already integrated on volume models, for example those in the Volkswagen ID. range, which centralizes a number of functions of the electronics architecture, enabling over-the-air updates. Thus, in addition to being able to correct any errors, the vehicle's software functions can be expanded; most sensors no longer have dedicated software, but are connected to a central application server. Only a few sensors in the vehicles are still directly linked to the processing of functions.

Unified platform
But this is only the first step: centralizing functions is key to managing complexities and carrying out over-the-air updates. So CARIAD is already working on the new unified architecture that will be available in Volkswagen Group vehicles from the middle of the decade. It will feature a unified software platform (VW.OS) and connect vehicles to the cloud (VW.AC), while at the hardware level, high-performance central computers will be used.
Sensors in the vehicle will be completely decoupled from the functions they perform; instead, a few zone controllers will take over the computation of simple tasks: these are small computers located in specific areas of the vehicle, such as the front and rear, placed close to the sensors to reduce cable lengths and capable of transmitting their data to the new high-performance computers via an Ethernet connection.
Easy updates
High-performance computers are at the core of the new unified architecture: they can control important sensors and also reliably perform very complex tasks. They will be critical to supporting Level 4 highly automated driving, which for example will allow cars to take control on highway routes, but needs algorithms that can learn themselves and act as artificial intelligence in the vehicle.
"The platform will be easy to update, something that will happen frequently and will require little customer interaction ", Alf resumes. This is because, in the future, the update will be for one software instead of many different ones each dedicated to one ECU. Thus developers will be able to send new features and error solutions at short intervals, and users will only need a few minutes to install them.
Modular and scalable
Since the new software platform will be integrated into millions of vehicles of all Volkswagen Group brands, its main features are modularity and scalability.
Depending on requirements, only one or several zone controllers may be used in the vehicles; the same applies to the high-performance computers. It will depend on the number of functions in the vehicle and their complexity. "With our unified architecture we’re scaling across all markets and segments covered by the Group, from volume vehicles to the premium class. The architecture is already looking to the future: because if chip performance increases, at some point everything will also be able to run via a single processor", Alf concludes.
Source: CARIAD
VGI | Responsible OU: VP | Creation date: article date | Class 9.1