Meeting Abstract
Insect flapping flight is inherently pitch unstable and therefore demands feedback control for effective maneuverability. This feedback control is primarily governed by actuation from the wings as well as airframe deformations which drive complex flight trajectories and compensatory responses to perturbations. Such airframe deformations in flying animals assist in flight control by changing the center of mass with respect to the center of lift. However, the dependence on redirecting inertia raises an important question about the consequences of body size in motor strategies for flight control. Furthermore, these motor strategies may limit the frequencies at which airframe deformations are effective methods for flight control. To address this question of body size implications to airframe flight control mechanisms, we rely on an Euler-Lagrange formulation for multibody dynamics for a simulated moth tracking a vertically oscillating flower. The simulation was inspired by methods from model predictive control. The model was tasked with tracking a signal composed of multiple sine waves of prime number frequencies. System identification reveals the model tracks lower frequencies with greater accuracy than higher frequencies. We then explored the underlying frequency characteristics of flower tracking for more than one order of magnitude body size range. We show that smaller size scales yield the lowest error in tracking this vertically oscillating stimulus. Therefore, the moth behaves as a low-pass filter with a size dependent cut-off frequency. These results suggest a benefit to movement control for multi-body systems of this scale. Such analyses of size scale may inspire new control mechanisms for aerial robots in general.
