A Simple Six Degree-of-Freedom Aerial Vehicle Built on Quadcopters

Conventional multirotors have coupling between position and attitude control due to underactuation in dynamics, and thus can not track six degree-of-freedom (DoF) trajectories in space. Previous works proposed fully actuated multirotors with modifications to mechanical structure to provide varying orientations of thrust forces without changing the attitude, but usually introduced additional actuators and mechanisms so that the complexity for design and construction was increased. This paper proposes a novel multirotor platform with the capability of six DoF control, which can be easily constructed with commercial quadcopters and simple 3D printed connectors, and effortlessly scaled. An easily implemented controller is designed, and the six DoF control is verified through simulation and real world experiments.

I. Introduction

Unmanned Aerial Vehicles (UAVs) have obtained increasing attentions in recent years. Multirotor UAV, among all popular configurations, shows its advantages on mechanical simplicity and high agility. Heavy investigations have been conducted on its control and analysis [1] on a wide range of applications, including surveillance, delivery, inspection and mobile network construction, as stated in [2] and [3].