Meeting Abstract
Accurately measuring the wing shape of flying animals is of great importance for accurate aerodynamic analysis. This is because the flow phenomena and resulting forces and moments are sensitive to subtle changes in shape. Historically, aerodynamic analysis of birds has mostly been reliant on approximate models of wing geometry or the use of animal cadavers placed in approximate flight configurations. Both of these approaches suffer the limitation that they are unlikely to accurately reproduce the in-flight geometry. Here, a new method for high resolution three-dimensional geometric measurement of free-flying birds is presented. A trained barn owl (Tyto alba) and peregrine falcon (Falco peregrinus) were flown outdoors past a set of eight synchronised DSLR cameras arranged in pairs above and below the bird’s flight path. The complete surface geometry of the bird in steady glide (approx. 1 million points) was measured using the new photogrammetric technique which is based on a phase correlation approach. The demonstrated accuracy of this new method is ± 2.5 mm for 95% of the points based on measurement of a life size model bird made under field conditions. The accuracy and resolution of the measurements far exceed anything so far achieved in bird flight research, and stands to significantly improve the accuracy of future analysis of bird aerodynamics and flight dynamics.
