Development and Viability of an Inverted Descent Quadrotor for Precision Aerial Delivery

Abstract

The field of Precision Aerial Delivery strives for the highest standard of accuracy, with sights set on delivering payloads from high altitudes to mere feet from goal locations.Quadrotors, due to high maneuverability and precision, are a logical choice to achieve this objective, however current inefficiencies of descent prevent quadrotors from use in Precision Aerial Delivery.Described herein are the development, experimentation and implementation of a near passive, Inverted Descent Quadrotor system. The Inverted Descent Quadrotor allows for high altitude deployment of a quadrotor fitted with standard hardware with the ability to descend more rapidly and with less energy requirement than previously possible. The decreased energy requirement of the Inverted Descent Quadrotor enables quadrotors to be used in high altitude scenarios, for missions that have previously been reserved for guided parachute or parafoil systems. Quadrotor systems thrive in such missions after descent, iii as they accommodate the potential for complex, highly precise activities to be completed once reaching ground.The development process consisted of wind tunnel thrust testing, a proof of concept single axis prototype, a functional Inverted Descent Quadrotor build, real world performance testing and mission simulation. Each stage of development provided valuable insight into the governing dynamics of rapid descent environments and informed the subsequent phases of development.Wind tunnel thrust testing helped to identify a potentially optimal baseline throttle to apply when facing high speed descent to maintain control authority, as well as quantify potential power savings. The single axis prototype proved control potential in an artificial descent environment, further quantified power usage, characterized potential glide performance and suggested control gains for the rapid descent environment. A functional Inverted Descent Quadrotor was then built and tested to prove initial functionality, and verify the results from single axis testing. The system was then tested to quantify control, power and glide performance against various configurations of normal quadrotor descent, as well as current comparable Precision Aerial Delivery Systems. Finally, the Inverted Descent Quadrotor s performance results were extrapolated to simulation to display the increased performance of the Inverted Descent Quadrotor in a mission setting.The Inverted Descent Quadrotor proved to be successful in reducing descent energy, which endowed high precision quadrotor systems the capability for descents far iv higher than previously possible. With far less sensitivity to wind prediction, coupled with the potential for payload capacity, the Inverted Descent Quadrotor showed promise worthy of future development and research.