The Avian Wing Morphing project measures dynamic morphing in bird wings using modern computer vision approaches to develop dynamic three-dimensional surfaces.
Using these models, we are exploring relationships between kinematics and force generation, identifying mechanisms of gust rejection and recovery, and modelling computational fluid dynamics to understand how forces are produced and distributed. These results will shed new insight into the interplay between passive/active wing morphing and aerodynamic force generation and may lead to a new generation of bird-sized aircraft.
The experiments are led by Dr Jorn Cheney of the Bomphrey lab and collaborator Dr Jonathan Stevenson of the University of Bristol's Bio-Inspired Flight Lab headed by Dr Shane Windsor. We are working with Lloyd and Rose Buck and their flock of birds.
We are measuring the three-dimensional surface of the wings, tail, body, and head of gliding birds as they fly down a specially-built flight corridor. We perturb the birds during their glides by providing either a static or dynamic change to their aerodynamic forces. We can then identify how they passively or actively respond or recover from these perturbations.
We calculate the three-dimensional surfaces of the birds using multi-camera high-speed videography combined with disparity map calculations of the surfaces (photogrammetry). By placing the our cameras in a careful array we can get views of the birds from several different angles at the same moment in flight, allowing accurate reconstruction. We have developed in-house code to segment the surfaces into regions and then use various methods to calculate both rigid-body rotations and surface deformations.
Dr Jialei Song has recently joined the group to run computational fluid dynamics on the deformable mesh models.
These experiments are part of a larger international project headed by Professor Dan Inman, in collaboration with a team of engineers and biologists: Professor David Lentink, Professor Yong Chen, Professor Darren Hartl, Professor Douglas Altshuler, Professor Fu-Kuo Chang, and Professor Henry Sodano.
Check back in the new year for new results!
We thank the European Office of Aerospace Research and Development for funding this project.