Identification of avian flapping motion from non-volant winged dinosaurs based on modal effective mass analysis
Fig 1
Seven-rigid-body system of Caudipteryx.
The simplified rigid body system illustrates the mechanism of moving parts, main body, wings, legs, neck and head, and the tail of the Caudipteryx. The masses of all parts are represented by lumped mass points and the muscles at the joints are replaced with springs (As damping coefficient does not significantly affect the natural frequency, we simplified the joints which are composed of tendons, muscles, ligaments and soft tissues as purely elastic springs with no damping). Different effective masses of these seven primary modes of the simplified Caudipteryx show different possibilities to be excited.