Pedestrians and cyclists are particularly vulnerable in traffic accidents. Statistics from the past ten years show that they account for 75 to 85 percent of all seriously and fatally injured individuals in Germany—even though they are only involved in about one in ten accidents. While the absolute number of fatalities continues to decline slightly—partly thanks to stricter requirements for vehicle structure design and driver assistance systems—the safety of vulnerable road users (VRUs) remains a critical challenge.

From brake assistance to advanced driving maneuvers

Existing driver assistance systems prevent or mitigate accidents or their consequences through braking maneuvers. In the VIRTUS project, the Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut (EMI), TU Berlin, and TU Chemnitz are investigating the extent to which injuries can be minimized by executing additional, targeted steering maneuvers—specifically in situations where a collision is unavoidable.

VIRTUS builds on findings from the predecessor project “ATTENTION”, funded by the Federal Ministry for Economic Affairs and Climate Action. Using cyclists and pedestrians as examples, the researchers demonstrated in a virtual test environment that injury risks can be reduced with targeted steering and braking interventions. Over the next three years, the project partners will verify whether this also works reliably under realistic conditions.

At the core is an algorithm that, based on sensor data, vehicle movement, and the predicted movement of the VRU, calculates a driving strategy in a very short time that minimizes injury risk.

Realistic testing in a virtual environment

For the tests, the project partners will use a highly integrated test bench consisting of four interconnected systems. In the “Vehicle-in-the-Loop” (ViL) system, a real vehicle drives on a test bench while the environment—such as approaching people—is simulated virtually and fed back to the vehicle in real time. The “Pedestrian-in-the-Loop” (PiL) test bench allows individuals to walk interactively through the same virtual traffic scene and perceive it from a pedestrian's perspective. The “Driver-in-the-Loop” (DiL) integrates a real driver into the system, so human reaction behavior at the steering wheel can also be considered. By coupling all three components, accident scenarios and the interaction of road users can be realistically recreated and studied — safely for everyone involved and in compliance with strict ethical guidelines. 

“In this test environment, we can investigate how an injury risk-minimizing vehicle control system behaves in interaction with real people and realistic hardware for the first time—without real risks for any of the people involved. This is an important step toward deployment-ready safety technology“, project leader Dr. Thomas Soot explains. Beyond testing the specific driving function, VIRTUS pursues another goal: the developed test methods and ethical guidelines should also be usable for other automated driving systems in the future. In this way, the project supports the safe development and testing of automated vehicle technology in Germany.