LARGE MOTION VISUALIZATION AND ESTIMATION FOR FLAPPING WING SYSTEMS

Studies of fluid-structure interactions associated with flexible structures such as flapping wings require the capture and quantification of large motions of bodies that may be opaque. Motion capture of a free flying insect is considered by using three synchronized high-speed cameras. A solid finite element representation is used as a reference body and successive snapshots in time of the displacement fields are reconstructed via an optimization procedure. An objective function is formulated, and various shape difference definitions are considered. The proposed methodology is first studied for a synthetic case of a flexible cantilever structure undergoing large deformations, and then applied to a Manduca Sexta (hawkmoth) in free flight. The three-dimensional motions of this flapping system are reconstructed from image date collected by using three cameras. The complete deformation geometry of this system is analyzed. Finally, a computational investigation is carried out to understand the flow physics and aerodynamic performance by prescribing the body and wing motions in a fluid-body code. This thesis work contains one of the first set of such motion visualization and deformation analyses carried out for a hawkmoth in free flight. The tools and procedures used in this work are widely applicable to the studies of other flying animals with flexible wings as well as synthetic systems with flexible body elements.

THE INTERPLAY PERFORMANCE PRACTICE: PLAY AND SOCIAL CHANGE IN LATE CAPITALISM

Practitioners of the performance form “InterPlay” utilize dance, storytelling and song to build community and generate social change. I elucidate how this community of practitioners conceptualizes “social change.” I argue that the InterPlay social movement organizes around the application of play to performances of self in everyday life. I explore how the InterPlay non-profit corporation, Body Wisdom Inc., employs this technique to address racial justice in its organizational practices. I also examine how practitioners understand their use of this performance play in places of work, concluding that—even in these endeavors—they see social change as a process immanent to both individual people and the systems they create, not as the intervention of an autonomous external power. Ultimately, I argue that, within late capitalism, play should no longer be conceptualized as an activity separate from everyday sociality but as an immanent process of change constitutive of a socioaesthetic domain.