Abstract: The dynamic analysis of launching and unfolding process of tandem-wing unmanned aerial vehicle is the key to the design of unmanned aerial vehicle and deployment mechanism. A multi-rigid body dynamic model of tandem-wing unmanned aerial vehicle is established based on Newton-Euler method, and the unsteady aerodynamic force in the process of wing unfolding is calculated based on the dynamic overset mesh method. The calculated unsteady aerodynamic parameters are compared with the steady aerodynamic parameters. The influences of wing unfolding speed and sequence on launching trajectory are analyzed on the basis of the aerodynamic changes in the wing unfolding process and the multi-rigid body dynamic model. The result shows that the excessively fast or slow speed of wing unfolding has a great disturbance to the launching trajectory. When the wing unfolding speed is too fast, the effect of inertia force plays a major role on disturbance. When the wing unfolding speed is low, the aerodynamic change shows a greater impact on disturbance. Meanwhile, the firstly unfolding of forward wings is not conducive to the stability of initial launching trajectory, but the firstly unfolding of backward wings has a beneficial effect on the stability of initial launching trajectory. The disturbance to the launch trajectory can be minimized when the forward and backward wings unfold together with the time of 0.20 s. Key

Key words: tandem-wingunmannedaerialvehicle, oversetdynamicmesh, multi-bodydynamics, launchdisturbanceanalysis, wingunfolding