The objective of the Explo-Drone project is to ultimately develop a compact micro air vehicle, capable of autonomously flying through highly confined environments such as collapsed building or prehistorical caves including narrow underground tunnels. The idea of the proposed research project is twofold. First, it aims at achieving a very efficient and compact micro air vehicle configuration combining endurance, compactness, a low aerodynamic signature and the capability to fly in the vicinity of walls without contact. The state-of- the-art in the field of compact micro air vehicle currently faces a downsizing problem related to the low- Reynolds number regime which dramatically degrades aerodynamic performances. In the present approach, the use of a new ducted coaxial rotor configuration is proposed in order to enhance the propulsive efficiency while minimizing the aerodynamic signature by a proper nozzle design. Second, the development of control laws and autonomous navigation in dimly lit unknown environment using a technique of vision and inertial sensor fusion is proposed. A nonlinear control design including the most advanced developments in the field of adaptive control will be addressed. The proposed project fosters the close involvement of two research partners concerned by an innovative concept of MAVs as applied to the field of Search & Rescue, Archeology and Environment.