Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics

Abstract

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.

Carpenter ants use diverse antennae sampling strategies to track odor trails

“…7B). This is consistent with evidence from drosophila that show adaptation within days after amputation (Wosnitza, 2013;Isakov, 2016;Muijres, 2017), as well as recent studies on ants showing robust performance across a range of olfactory behaviors after unilateral antenna amputation (Waxman, 2017). This resulting behavioral change in antennae movement may partially explain how the single antenna ant is able to maintain a level of estimated odor information similar to what one antenna of a control ant receives despite greater deviation from the trail (Fig.…”

Simulated moult reduces flight performance but overlap with breeding does not affect breeding success in a long‐distance migrant

“…The escape manoeuvres that we measured in the plucked birds ( Figure 1c) were the result of a complex interaction between physical effects of wing gaps on flight performance in the form of a reduction in the distance travelled per wingbeat (Figure 3a), and a behavioural response in which the plucked birds overcompensate for the detrimental effects of moult on wing morphology (Figure 3f). The reduction in second moment of wing area as a result of our treatment, negatively affects the ability to produce aerodynamic forces (Muijres et al, 2016;Weis-Fogh, 1973), and the plucked birds with lowest S 2 respond to this by flying at the highest escape speed (Figure 3f). Because of this overcompensation to a reduction in S 2 , flight speed is not significantly different between the plucked and control group (Figure 3e).…”

“…For flapping flight at low flight speeds, such as the vertical flight manoeuvres in our experiments, the distal part of the beating wing moves faster than the proximal wing section, and therefore contribute more to aerodynamic lift production. For this reason, the aerodynamic forces produced by a beating wing at low flight speeds scale approximately linearly with the second moment of area S 2 of that wing (Muijres, Iwasaki, Elzinga, Melis, & Dickinson, ; Weis‐Fogh, ). And thus, to quantify the effect of wing morphology on flight performance, we determined the second moment of area for both wings of each bird, based on the videography images.…”

“…moves faster than the proximal wing section, and therefore contribute more to aerodynamic lift production. For this reason, the aerodynamic forces produced by a beating wing at low flight speeds scale approximately linearly with the second moment of area S 2 of that wing (Muijres, Iwasaki, Elzinga, Melis, & Dickinson, 2016;Weis-Fogh, 1973).…”

Coevolving advances in animal flight and aerial robotics

“…In contrast to robots, when flying insects suffer wing damage, they quickly adjust their wingbeat pattern and continue to fly [8]. Muijres et al [8] show that flies can continue flying even with half their wing removed, and that they achieve this using a sophisticated control system. Based on these findings, they derived a general damage control algorithm for flapping flight that can be particularly insightful for roboticists.…”