Meeting Abstract
Birds are able to maneuver their wings into an impressive array of shapes to fly through a variety of environments and accommodate different flight modes. Their articulated wings have many similarities to human arms with corresponding elbow and wrist joints. These joints allow both flexion and extension as well as more subtle movements. This motion is caused by interaction of the humerus, radius, ulna and carpometacarpus and the smaller wrist bones with each other and the surrounding tendons and muscle tissue. We examine how the skeletal architecture causes these changes in wing shape by reconstructing the individual bone positions and joint axis of motions in a racing pigeon wing during several representative posture transitions. We show how the wrist and elbow joints compare to ideal pin and ball-and-socket joints by analyzing how the axes of each change during wing motion, as well as how these axes compare to the bone joint surfaces. We also examine coupling of different bone motions and how automating mechanisms, closed kinematic chains, and shared radioulnar motion effect the overall wing morphing mechanism.
