An investigation of 6-DOF insect flight dynamics with a flexible multibody dynamics approach

Abstract

In this study, we develop a flexible multibody model of the Hawkmoth <i>Manduca Sexta</i> and its six degrees of freedom (6- DOF) flight dynamic simulation environment. The wings of the Hawkmoth model are constructed as a flexible structure which has similar structural dynamic characteristics to the real Hawkmoth wings. The other body components: head, thorax, and abdomen are also modeled independently to consider each component’s mass and inertia properties. Based on this flexible multibody dynamics environment, a wing kinematics that enables a hovering flight of the Hawkmoth model is searched. This kinematics is compared with experimentally measured wing kinematics from literature, and the result shows that a slight modification to the measured wing kinematics is sufficient to reproduce the hovering flight of the Hawkmoth model. The 6-DOF flight dynamic states at the hovering condition are also computed and these state variables are compared with those of a rigid-winged Hawkmoth model to see the effect of the flexibility on the flight dynamics. Here, the rigid- and flexible-winged Hawkmoth models are the same except for the wing flexibility. A qualitative and comparative analysis is performed on the 6-DOF flight states during the hovering flight between the two Hawkmoth models, and the effect of wing flexibility on the flight dynamics is addressed.