Accession Number:

ADA551615

Title:

Modeling Interactions Between Flexible Flapping Wing Spars, Mechanisms, and Drive Motors

Descriptive Note:

Journal article

Corporate Author:

AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIR/CONTROL SCIENCES DIV/CONTROL DESIGN AND ANALYSIS BRANCH

Report Date:

2011-09-01

Pagination or Media Count:

29.0

Abstract:

A system of dynamical equations is presented that allow micro air vehicle MAV or- nithopter designers to match drive motors to loads produced by exible apping wing spars. The model can be used to examine the coupled system-level behavior of brushed DC motors, gear trains, and any number of linkages and exible wing spars. A Lagrangian approach is used to derive the governing di erential equations of motion for a class of or- nithopter drive systems. Methods used to determine parametric constants contributing to generalized force components, which cannot be derived from first principles, are described. An example is presented where simulation results are compared to experimental measure- ments. The results show that the di erential equations correctly predict major trends in observed motor speed and wing spar structural deformation over the course of each wingbeat. The results show that when pairing ight-weight motors and wings, signi cant variations in drive motor speed occur throughout each wingbeat. It is shown that cou- pling between motor speed, wing loads, and structural exibility cause the aerodynamic forces encountered by the wing spars to depart from those predicted by rigid-spar and constant-velocity-motor-based kinematic simulations.

Subject Categories:

  • Pilotless Aircraft
  • Numerical Mathematics
  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE