The winner of the iCan 2011 competition, which revolves around the topic of microsystems technology, was the team from Saarland University with a sophisticated control strategy for quadrocopters. Quadrocopters and model helicopters are not easy to fly - especially for beginners. Operating errors can quickly destroy these expensive devices. The assistance system developed by the students takes over the height control (distance control), intervenes in critical situations and ensures the necessary safety distance to obstacles (anti-collision). The students use ultrasound-based distance measurements in their concept. The algorithms (PD anti-collision controller; PID for altitude) were implemented in a microcontroller that also supports automatic take-off and landing procedures.