Design and Development of a Micro Air Vehicle (μav) Concept: Project Bidule

This paper presents an analysis of the concept of Miniature Air Vehicles and Micro Air Vehicles (respectively mAV and μAV) mainly carried out through the development of a mAV prototype called "Bidule", which was first successfully flown in 1998. The final objective of the project is to reduce the size of this miniature demonstrator to a micro sized vehicle. This paper presents the initial work done to achieve this goal with a particular interest in the aerodynamics of the present vehicle. In keeping with the context of a vehicle’s size reduction, a preliminary quantitative approach of the concept shows that the tiny size of mAVs and μAVs creates a strong coupling between the different design fields and requires a high degree of integration. Therefore, reducing the size of an aerial vehicle has major consequences on the performance, especially in terms of endurance. Conserving the operational capabilities of the "Bidule" then requires considering the interactions between the different design parameters, with a particular attention being paid to the wing loading and a high maximum lift. The wind tunnel testing of a propelled model of the "Bidule" prototype shows that the basic design benefits from the prop-wash effect in terms of increased lift. In the context of size reduction to the present vehicle, the results suggest keeping the idea of a wing body immersed in a propeller slipstream, providing that the destabilising effects due to the power system and the prop-wash can be kept to an acceptable level.