FlexCAR: Vehicle platform for the mobility of the future

The requirements for future vehicles are increasingly shifting from pure hardware to flexible software instances. This makes it possible to react quickly and efficiently to changing demands on computing resources due to functional adaptations, updates or even hardware failures. One of the key criteria is the open development process with the aim of developing and implementing open interfaces for hardware and software. Flexibility in development plays just as important a role as the ability to make adjustments via updates after the vehicle has been rolled out. The continuous improvement of existing algorithms, the exchange with internal sensors and the integration of external sensors beyond the system's own limits place high demands on flexibility, which can be achieved through the use of an open development platform and a software-orientated architecture.

In order to meet these challenges, the Fraunhofer Institute for Industrial Engineering IAO and the Institute of Human Factors and Technology Management IAT at the University of Stuttgart researched the design of open, long-term interfaces and suitable network communication using the "Rolling Chassis" research platform. As part of the FlexCAR joint project, integrated yet flexible onboard and offboard communication via 5G was realized in the indoor ARENA2036 environment. The onboard network provides fast and secure communication. Standardized, service-oriented message protocols allow all network participants to integrate into the onboard communication. The offboard connectivity provides communication via the air interface. This allows over-the-air updates without the need for a visit to the workshop. Remote maintenance not only enables control functions to be carried out, but also allows all onboard data to be shared for visualizations or calculation capacities to be flexibly transferred to the cloud. At the same time, communication with external devices is a fundamental requirement for Vehicle-2-everything connectivity (V2X).

As part of the FlexCAR joint project, a purely electrically powered and fully X-by-wire controlled research vehicle, the Rolling Chassis, is being developed.

The FlexCAR vehicle platform is based on open interfaces and is highly modular in terms of drive systems, body variants and software components. This gives future vehicles enormous flexibility and adaptability, both in terms of hardware and software. As a result, the life cycle of a vehicle is considerably extended and at the same time kept at the cutting edge of technology. Adaptations to the needs of people and the environment can therefore be made at any time. Standardized interfaces make it easy to exchange software and hardware modules. The 5G interface makes it easy to carry out over-the-air updates or integrate external sensors. Data is exchanged within the FlexCAR via the DDS communication middleware, which was provided in this context by RTI Connext® from RTI. This enables a reliable, real-time capable and flexibly customizable exchange of information between all control units and communication participants in the internal Ethernet network of the rolling chassis. Thanks to a software-orientated architecture, zone-based domains can be operated, and an intelligent computing load distribution can be implemented. Thanks to the probabilistically developed architecture of the software and hardware, it is possible to upgrade the system at a later date without major customization costs. The provision of computing resources and the distribution of the computing load helps to compensate for any bottlenecks and ensure the robustness of the system. FlexCAR thus represents a pioneering pillar in vehicle development and has the potential to shape the mobility of the future. The combination of open interfaces, modularity and a software-orientated architecture brings with it a multitude of advantages. The platform offers a flexible basis for the development of new mobility concepts that can be updated and upgraded to meet the needs of people and the environment.