title: Automatic analysis and characterization of the hummingbird wings motion using dense optical flow features.
abstract: A new method for automatic analysis and characterization of recorded hummingbird wing motion is proposed. The method starts by computing a multiscale dense optical flow field, which is used to segment the wings, i.e., pixels with larger velocities. Then, the kinematic and deformation of the wings were characterized as a temporal set of global and local measures: a global angular acceleration as a time function of each wing and a local acceleration profile that approximates the dynamics of the different wing segments. Additionally, the variance of the apparent velocity orientation estimates those wing foci with larger deformation. Finally a local measure of the orientation highlights those regions with maximal deformation. The approach was evaluated in a total of 91 flight cycles, captured using three different setups. The proposed measures follow the yaw turn hummingbird flight dynamics, with a strong correlation of all computed paths, reporting a standard deviation of [Formula: see text] and [Formula: see text] for the global angular acceleration and the global wing deformation respectively.
authors.affiliation: Computer Imaging and Medical Applications Laboratory-CIM@LAB, Universidad Nacional de Colombia, Colombia.
authors.forename: Fabio
authors.initials: F
authors.lastname: Martínez
authors.forename: Antoine
authors.initials: A
authors.lastname: Manzanera
authors.forename: Eduardo
authors.initials: E
authors.lastname: Romero
mesh_terms: D000818:Animals; D001717:Birds / Q000033:anatomy & histology / Q000502:physiology*; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology; D005426:Flight, Animal / Q000502:physiology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008954:Models, Biological; D009068:Movement / Q000502:physiology; D010781:Photography / Q000379:methods*; D012212:Rheology / Q000379:methods; D033081:Shear Strength / Q000502:physiology; D013314:Stress, Mechanical; D014741:Video Recording / Q000379:methods*; D014921:Wings, Animal / Q000033:anatomy & histology / Q000502:physiology*