Modeling and Attitude Control Analysis of a Spherical VTOL Aerial Vehicle

Abstract

The aim of this paper is to present a con guration for a multi-functional spherical robotic vehicle designed for search and rescue purposes, which combines the advantages of hover, level ight, and ground mobility. The spherical frame allows the vehicle to encounter an object without the risk of damaging the propeller and onboard components, and can land anywhere without the need of coordinated landing maneuverability. Called the Unmanned Flying and Rolling Orb (UFRO), the Japan Flying Sphere (JFS) developed by the Technical Research and Development Institute (TRDI) of Japan is used as the template for the preliminary design. The current prototype consists of a single propeller and eight control vanes enclosed in a reinforced spherical frame. A detailed dynamic model is established using the Newton-Euler formulation and linearized to estimate the attitude for hovering ight in trim conditions. Successful attitude stability during takeo and maintaining hover-mode ight is demonstrated using a COTS PID controller.