Meeting Abstract
Flying animals must perceive and avoid obstacles, often in environments deprived of sensory cues. In particular, nocturnal mosquitoes must divert away from surfaces or land gently when visual cues are unavailable, indicating a short-range, non-visual collision avoidance mechanism. We hypothesised that this is mediated by mechanosensory feedback, with mosquitoes detecting and reacting to modulations of their own induced aerodynamic and acoustic fields as they enter ground- or wall-effect. We investigated the sensory information available for these two putative mechanisms for sensing obstacles through computational fluid dynamics and aeroacoustic simulations of low-altitude and near-wall mosquito flight. Our simulations are based on detailed wing kinematics extracted from high-speed recordings of free 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 a new computational aeroacoustic simulator, we also calculated the acoustic pressure distribution around the mosquito in the near and far fields. The simulations suggest a strong directionality in the magnitude and dominant frequencies of the acoustic signature that could be encoded to detect surface proximity and directional vectors, or for intraspecific communication. Using these insights we built and flew an aerial robotic prototype carrying the bioinspired sensor.
