Fig. 1: Comparing drones’ and birds’ strategies to perform a turn maneuver.
From: Sharp turning maneuvers with avian-inspired wing and tail morphing
a During the roll phase, the aircraft produces a roll motion by generating a lift asymmetry between the two wing sides until they reach their desired bank angle. b During the bank phase, banking results in a vertical lift component, which counterbalances the weight force and an inward facing, horizontal lift component which leads to turning. c To roll, drones commonly use ailerons, flaps that are deflected in opposition to each other. d To increase lift when turning, drones deflect their elevator upward, which increases the angle of attack, and hence the lift force. e Birds apply two main strategies for rolling. They use folding by extending one wing side and folding the other, or use twisting by pronating one wing side and supinating the other. f When turning, birds increase the lift force by elevating their tail and extending both wing and tail.
