Aerospace (ISSN 2226-4310) open access journal of aeronautics and astronautics published quarterly online by MDPI.
Multirotor is the umbrella term for the family of unmanned aircraft, which include the quadrotor, hexarotor and other vertical takeoff and landing (VTOL) aircraft that employ multiple main rotors for lift and control. Development and testing of novel multirotor designs has been aided by the proliferation of 3D printing and inexpensive flight controllers and components. Different multirotor configurations exhibit specific strengths, while presenting unique challenges with regards to design and control. This article highlights the primary differences between three multirotor platforms: a quadrotor; a fully-actuated hexarotor; and an octorotor. Each platform is modelled and then controlled using non-linear dynamic inversion. The differences in dynamics, control and performance are then discussed.