Realistic Modeling of
Bird Flight Animations

Jia-chi Wu

Zoran Popović

raven taking off


In this paper we describe a physics-based method for synthesis of bird flight animations. Our method computes a realistic set of wingbeats that enables a bird to follow the specified trajectory. We model the bird as an articulated skeleton with elastically deformable feathers. The bird motion is created by applying joint torques and aerodynamic forces over time in a forward dynamics simulation. We solve for each wingbeat motion separately by optimizing for wingbeat parameters that create the most natural motion. The final animation is constructed by concatenating a series of optimal wingbeats. This detailed bird flight model enables us to produce flight motions of different birds performing a variety of maneuvers including taking off, cruising, rapidly descending, turning, and landing.

Full text


eagle turning

Video shown at SIGGRAPH 2003 presentation (QuickTime 39.2 MB) (DivX 33.1 MB)

raven landing

Raven landing (QuickTime 138 KB)

eagle turning

Eagle turning (QuickTime 173 KB)


July 2003