Multicopter Dynamics in Small Uninhabited Aerial Systems

Abstract

Quadcopters and other multicopters were one of the first considered vertical take-off and landing vehicle configurations for heavier than air transport in the early 20th century. After the success of Oehmichen’s No. 2 Quadcopter and de Bothezat Quadcopter in the 1920s, multicopter designs slowly faded until a reemergence into the small unmanned aerial systems realm as toys. With the beginning of the 21st century, quadcopters have become a mainstream object with many commercial vehicles available for personal or professional usage. However, since the reemergence, the academic work on these small multirotor UAS as remained largely separated from the academic work on larger manned vertical take off and landing systems. This thesis works to review fundamental theory from basic dynamics and rudimentary aerodynamics of helicopter flight before analyzing the current state of small multicopter modeling and control to identify weaknesses in current approaches. This work also uses flow visualization and ground effect testing to help illuminate some multicopter aeromechanic and vehicle dynamics couplings that are not currently being observed from current quadcopter models. These observations can be used in the development of future robust controllers for these multirotor platforms.