Session: MESA-06 / MESA-11 / MESA-15

Paper Number: 114020

114020 - An Experimental Study of Drag Coefficients of a Quadrotor Airframe 

This paper investigates the aerodynamic drag coefficients of
a standard cross-geometry quadrotor airframe at varying pitch
and yaw angles, using a wind tunnel. The quadrotor airframe
was mounted in the wind tunnel at fixed pitch and yaw angles,
and subjected to a range of wind flow speeds. Drag forces created
by the mounting systems used were measured and removed
from subsequent drag force measurements. The drag force on
the airframe at these speeds and attitudes was measured, and
used to identify lumped drag-area coefficients. The variability of
these coefficients was observed both with and without unpowered
propellers mounted on the airframe. It was found that these parameters
increased with increasing angle, and were larger with
propellers mounted on the airframe. Measurements were also
taken at mixed pitch/yaw orientations to determine whether a relationship
exists between these drag-area coefficients and ones
taken at individual pitch and yaw angles. Validation was performed
using computer vision estimates of projected areas and
comparison with drag coefficients of geometric shapes. Fourier
series models were fit to the drag-area coefficient trends to create
estimator functions. The pitch axis estimator functions had
adjusted 𝑅2 coefficients of 0.976 and 0.932, while the adjusted
𝑅2 coefficients for the yaw axis were 0.733 and 0.508 (without
and with propellers respectively). The measured drag-area parameter
values and fitted estimator functions provide reference
values for quadrotor airframe design, simulation and controller
development for model-based controllers.

Presenting Author: Daniel Morris University of Canterbury

Presenting Author Biography: Daniel Morris (BEng, Hons) is a current PhD candidate whose research focus is creating adaptive flight controllers for autonomous unmanned aerial vehicles. Based at the University of Canterbury, New Zealand, Daniel has extensive experience with mechatronics systems, embedded controls applications and engineering education.

Authors:

Daniel Morris University of Canterbury
Chris Pretty University of Canterbury