Lift calculations based on accepted wake models for animal flight are inconsistent and sensitive to vortex dynamics

@article{Gutirrez2016LiftCB,
  title={Lift calculations based on accepted wake models for animal flight are inconsistent and sensitive to vortex dynamics},
  author={Eric B. Guti{\'e}rrez and Daniel B. Quinn and Diana D. Chin and David Lentink},
  journal={Bioinspiration \& Biomimetics},
  year={2016},
  volume={12}
}
There are three common methods for calculating the lift generated by a flying animal based on the measured airflow in the wake. However, these methods might not be accurate according to computational and robot-based studies of flapping wings. Here we test this hypothesis for the first time for a slowly flying Pacific parrotlet in still air using stereo particle image velocimetry recorded at 1000 Hz. The bird was trained to fly between two perches through a laser sheet wearing laser safety… 

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