Dynamics simulation of a folding wing unmanned aerial vehicle with the parachute system assisted launching

This paper mainly focuses on a series of dynamic problems caused by a small folding wing Unmanned Aerial Vehicle (UAV) with a parachute system assisted launched from the high-altitude balloon platform. The simulation contents are the four-stage motion processes of the “parachute-UAV system” after separation from the balloon platform, including the straightening stage, the inflation process, the stable descend under the influence of the wing deployment action, and the trajectory leveling of the UAV. The “parachute-UAV system” is equivalent to a multi rigid body connection structure. We introduce the straightening length parameter and the wing deployment angles based on the Kane method to establish the dynamic model. And we choose the inflation time method to simulate the parachute deployment process and the flat plate high angle of attack model to describe the wing aerodynamic force. In the simulation, we compare six launching processes of different wing deployment time periods and obtain the separation state of each UAV when cut from the parachute. We adopt the Radau Pseudo-Spectral method to calculate the leveling trajectory of six UAVs. This paper is an engineering application research study and can provide a simulation reference for the launching test of the balloon-borne folding wing UAV system.