Vectored-thrust system design for a tail-sitter micro-aerial-vehicle with belly/back takeoff ability

The tail-sitter configuration has the advantage of being capable of vertical takeoff and landing. However, it may confront takeoff and landing difficulties in an atmosphere environment with gusts, especially for the miniature design of micro-aerial-vehicles (MAVs). Typically, a tailer-sitter can takeoff from an erect posture, if it falls down accidentally, it is difficult to restore its original start-up posture without human involvement. To address this problem, a novel design method for a tail-sitter MAV has been introduced with unique takeoff and landing modes, which enable it to fly from any start-up attitude. The key design parameters are provided and tested using flight dynamics simulation modelling. It is found that, the takeoff distance is closely related to the moment arm, maximum deflection angle, and servo deflection rate of a vectored-thrust system, based on which the minimum value of altitude command can also be defined. A flight test of prototype has been conducted to verify the feasibility of the design method proposed in the current study.