Mechanics of hummingbird flight: upstroke vs downstroke performance
In flapping flight, a wingbeat is divided into two motions, an upstroke and a downstroke. The two motions are powered by separate muscles, and contribute different amounts of aerodynamic force to the total force. Hummingbirds are able to modulate the total aerodynamic force they produce to perform different flight behaviors. Previous work studying how hummingbirds modulate force examined only kinematic parameters that describe the entire wingbeat, but not parameters that describe the separate motions and contributions of the upstroke and downstroke. The goal of this study is to use a combination of direct force, kinematic, and muscle activity measurements to determine how the upstroke and downstroke are differentially controlled to modulate aerodynamic force production. The experiments will be repeated on multiple species with various wing morphologies to determine how wing morphology affects differential stroke usage and overall force production.
The fellow will be trained in husbandry of hummingbirds, muscle physiology techniques, biomechanical fieldwork, and phylogenetic analysis. Broader Impacts of the research include developing a new method for directly measuring whole body forces on a flying animal, and providing results that can help inform the programming of micro air vehicles. As part of the proposed work, the fellow will work with the Special Populations and Programs coordinator at the host university to develop workshops that help underrepresented students prepare for the graduate school application process. The fellow will also work with the local biodiversity museum to develop a public lecture and exhibit on flight.
