Kinematic modeling and analysis of transmission mechanism with joint clearance for flapping wing micro aerial vehicle

A theoretical model is built to reveal the effect of the joint clearance on the kinematic performance of the transmission mechanism of a flapping wing micro aerial vehicle (FWMAV). Massless link approach is used to model the joint clearance and the reciprocal screw is introduced to solve the kinematic model. Finite element method simulations are also performed to validate the model. The kinematic model reveals that the inertia force of the transmission mechanism contributes little to the flapping motion whereas the sign of the resultant moment of aerodynamic drag and wing inertia force plays decisive role. Besides, the joint clearance can either increase or decrease the flapping angle of the wing during a flapping period and it will significantly affect the flapping amplitude while involves little in the mean flapping angle. The effects of the positions of the joint with clearance and its magnitude on the flapping motion are also revealed.