In the TREE-research field Efficient Mobility the scientists focus on efficient alternatives in transport, from the development of new approaches to flow measurement, from models for the expansion of charging infrastructure to the acceptance of electric bicycles as part of sustainable mobility. Not only the engine but also design and construction are decisive factors for the efficiency of a vehicle. Professor Alexander Asteroth and his research group focus on vehicles which deviate from classic and already known concepts. Velomobiles are special three-wheeled bikes, which are covered in a streamlined case. They can be driven by muscle power as well as in combination with an electric engine. With the help of specific software, Asteroth’s team is working to optimise the interaction of muscle power and engine as well as the steering. The scientists aim to analyse how vehicle bodies can be optimised to reduce aerodynamic drag and thus energy loss. Therefore, they don’t measure in a wind tunnel but during free driving under real conditions and using a hexacopter which flies autonomically and is equipped with a camera.