Agile turnaround using post-stall maneuvers for tail-sitter VTOL UAVs

Miniature vertical take-off and landing unmanned aerial vehicles (VTOL UAVs) make various missions possible alone such as surveillance in partially-destroyed building and at broad hazard area where many obstacle exist. In such missions, agile turnaround using post-stall maneuvers is useful to avoid obstacles. This paper discusses agile turnaround strategies utilizing post-stall maneuvers for tail-sitter VTOL UAVs. Two agile turn strategies are studied in this paper: (1) minimum travel distance turn, and (2) minimum radius turn. The proposed strategies are formulated and optimization problems are solved. Through computer simulation, the proposed strategies are evaluated in terms of travel distance and turning radius comparing with conventional Immelmann turn strategy.