This book is a result of the European framework project muFly, aiming at the design and realization of an autonomous micro helicopter comparable to a small bird in size and mass. It introduces two prototype designs for the muFly helicopter: a modular one for fast sensor and actuator exchange and easy configuration testing, and a highly integrated design to reduce the total mass and integrate the complete sensor set for autonomous flight. Furthermore, a theoretical foundation for coaxial micro helicopter design is laid. In particular focus are passive stabilization and steering principles of...