Autonomous Flight Take-off in Flapping Wing Aerial Vehicles

This paper presents the design and dynamic simulation of a jumping mechanism for flight initiation in flapping wing aerial vehicles to enhance their autonomous mobility. It is inspired by avian flyers that start flight by jumping using their hind limbs. A 4-bar linkage that performs the prescribed take-off maneuvers has been geometrically designed using dimensional synthesis by motion generation. The kinematic dimensions obtained thereof have been ascertained analytically. A magnetic latching solenoid actuator and its corresponding transmission mechanism has been proposed for jumping actuation due to its compact structure, and low power consumption with no heat nor electrical noise generation. After take-off, the necessity to sustain the aerial vehicle airborne by providing adequate supportive forces at low air speeds has been demonstrated by the prospect of unsteady aerodynamics. Fluid-structure interaction has been analyzed by co-simulation between ADAMSⓇ and MATLABⓇ/Simulink. The designed legs give an inclined take-off of about 64° and an initial speed of almost 2m/s with an angular deflection of 110° between the leg segments. Flight performance indicates an increase in lift/drag ratios with in both flapping rate and forward velocity up to some limit. The results also compared favorably with those from wind tunnel tests and previous analysis of related work. They all exhibited an increase in wing efficiency with decreasing mean angles of attack as the air vehicle approaches stable flight.