Translational damping on flapping cicada wings

Abstract

We measured the dynamic damping of a pair of flapping cicada wings mounted on a robotic insect thorax mechanism capable of high frequency flapping. The damping coefficients were derived based on the measurements of the wing-thorax mechanism translating along its body principal axes. The robotic mechanism has a 10cm wingtip-to-wingtip span, flaps up to 65Hz, and weigh 2.86 gram including the motor and wings. To measure the flapping induced damping during translation, we developed a pendulum system mounted with encoder, and attached the flapper at the end and in different orientations such that its motion is along its principle axes. The damping of the flapper is then calculated from the decaying rate of the magnitude of the oscillating pendulum. The damping coefficients calculated from the experiments are very close to those estimated based on our mathematic models using Blade-Element Theory (BET) and quasi-steady aerodynamic models. As expected, the damping linearly increases with the flapping frequency and is most prominent along forward/backward direction.

A multibody approach for 6-DOF flight dynamics and stability analysis of the hawkmothManduca sexta

“…The aerodynamic model used in this study was based on a quasisteady blade element approach and the wake interaction was not considered; therefore, the up/down results may not coincide with the experimental results. In this study, the x sp -directional (forward/backward) translation exhibited the highest damping (t half,u = 7.10) while the y sp -directional (sideslip) translation was the least damped DOF (t half,v = 17.95), which had a trend qualitatively similar to the experimental study (Parks et al 2011). In conclusion, for the translational movements, there was a passive damping in all the DOFs.…”

“…The x sp -directional (forward/backward) translation and the z sp -directional (up/down) translation showed similar damping characteristics, except for the descending dynamics of the up/down translation. As Parks et al (2011) pointed out in their experimental study with translational damping of Cicada wings, the up/down translation is more complicated because wing-wake interaction is presented in this case. The aerodynamic model used in this study was based on a quasisteady blade element approach and the wake interaction was not considered; therefore, the up/down results may not coincide with the experimental results.…”

Large-Area Piezoelectric PVDF Fibers Fabricated by Near-Field Electrospinning with Multi-Spinneret Structures

“…In the experiment, we used the wing of Formosan Bear Cicada (scientific name: Cryptotympana holsti ) to test if it is possible to apply PVDF fibers on insect sensing. It is reasonable to estimate that the flapping frequency of cicada is between 10–50 Hz [ 27 ]. We coated silver gel as electrodes in the bigger skeleton of a cicada’s wing.…”