Meeting Abstract
In jumping take-off birds are known to generate forces up to eight times their own weight. While the wings do help out, the bulk of this effort comes from the legs. Given the opportunity birds will often choose to avoid this exertion by diving from the edge of a perch, exploiting gravity for acceleration. But in many instances this is not an option, and birds must take-off from the ground and climb. To explore these ground-based take-offs a theoretical model has been developed that captures the dynamics of the legs and the wings. This model extends previous flight performance models by accounting for the energetic cost of becoming airborne from rest. A sensitivity analysis is applied to the model to examine which kinematic, aerodynamic and inertial parameters dominate the overall take-off performance. The findings help to identify the most relevant variables that should be recorded in future experiments on avian jumping. The model is also used to examine the trade-off between jumping capability and cruise performance, showing how strong, powerful legs make for an easier departure, but carrying this extra baggage can be costly when up in the air.
