Traditional vertical take-off and landing micro aerial vehicles (VTOL MAVs) are generally underactuated, i.e., equipped with fewer actuators than degrees-of-freedom (DOF). As a consequence, they possess a limited mobility because of the inherent underactuation (e.g., they can neither translate laterally with a zero attitude nor hover at a spot with a nonzero attitude). In this paper, we present the design of a novel MAV, the Omnicopter, with two central counter-rotating coaxial propellers for thrust and yaw control and three perimeter-mounted variable angle ducted fans to control roll and pitch and provide lateral forces. It can work under two configurations, a fixed 90° ducted fan angle configuration and a variable angle ducted fan configuration. The variable angle configuration provides full actuation to the Omnicopter position/attitude. After a brief introduction of the Omnicopter platform, we discuss the control design, allocation and implementation for the two configurations separately. Simulations and experimental results verify the performance of the Omnicopter.

This paper presents an original configuration of a micro aerial vehicle (MAV), the Omnicopter. Two central counter-rotating coaxial propellers provide a major part of lift force, and three perimeter-mounted tiltable ducted fans are used to supplement the lift force, provide lateral forces and adjust its attitude. Different from traditional underactuated MAVs, the presence of the tilt-rotor mechanism, composed of three ducted fans and three servo motors, on the Omnicopter makes it over-actuated. The characteristic of over-actuation enables the Omnicopter's position dynamics to be decoupled from its attitude dynamics. Based on a complete description of its dynamic model derived using the Newton-Euler motion equations, we propose attitude and position controllers and control allocation for the Omnicopter MAV. Simulation and experimental results are shown to demonstrate its performance.