Design of attitude solution algorithm for tail-sitter VTOL UAV

Abstract

The tail-sitter Vertical Takeoff and Landing (VTOL) Unmanned Aerial Vehicle(UAV), flying in a fixed-wing model, overcomes many shortcomings of traditional fixed-wing UAVs, and inherits the advantage of high overall efficiency, which means it has great development potential and very broad application prospects. The attitude of tail-sitter VTOL UAV shows a wide change range in its takeoff and landing stages, and when the attitude sensor changes more than 90 degrees in pitch direction, the Euler angles converted by the Quaternions will have singular points, which means gimbal deadlock appears. From the solution algorithm, this paper provides a method of changing the order of rotation to avoid the appearance of singular points. The results show that this method can be well applied to the attitude solution of the VTOL UAV.

Keywords

• aircraft control
• tail-sitter VTOL UAV
• attitude measuring
• quaternion
• Euler angle
• gimbal deadlock