Abstract

I will present two recent examples of how fundamental bioscience research can teach us about animal ecology, and also offer solutions to engineering challenges.

Flying animals must perceive and avoid obstacles, often in environments deprived of visual sensory cues. In my first example, I will show how collision-avoidance in nocturnal mosquitoes can be mediated by mechanosensory feedback, based on modulations of their own induced aerodynamic and acoustic fields as they enter ground- or wall-effect. Our computational fluid dynamics and aeroacoustic simulations are derived from detailed wing kinematics extracted from high-speed recordings of freely flying Culex quinquefasciatus mosquitoes. Results reveal areas of relative pressure changes that are associated with close proximity to the ground and wall planes and that could provide useful information to the flight controller: a mechanism we term ‘aerodynamic imaging’. Using these insights we successfully built an aerial robotic prototype carrying a bio-inspired sensor package.

In my second example, I will present our work based on measuring the changing shape of birds in flight. I will show how they minimise drag in a different way from aeronautical design, and how they remain unperturbed by strong gusts. Our detailed three-dimensional reconstructions of surface geometries show how wing elevation around the shoulder joint acts as a suspension system that rejects gusts. The mechanism works most effectively when the aerodynamic centre of pressure is aligned with the mechanical centre of percussion, and therefore can be tuned either by changing wing shape or by the distribution of mass within the wing.

https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/fluid-mechanics-webinar-series