Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Northeastern University, 2008. / Title from title page (viewed Aug. 4, 2009) Graduate School of Arts and Sciences, Dept. of Biology. Includes bibliographical references.

Thesis (M.S.)--Ohio State University, 1985. / Includes bibliographical references (leaves 101-103). Available online via OhioLINK's ETD Center

No description available.

Both bird and fish locomotion are thought to be more efficient than the equivalent man-made vehicles driven by propellers/impellers and jet engines. Through studies that decompose the different kinematic and shape effects of these biological systems, we can understand what leads to their high cruising performance and efficiency. Two major studies were conducted. The first was on the effect of different kinematic parameters of large soaring birds on flight performance and the second was on the effect of caudal fin shape on the performance of thunniform swimmers. For the first study on flight performance, flapping, folding, and twist were the wing motions of interest. The second study on swimming performance observed how caudal fin sweep angle affects propulsion while isolating the effect of this shape difference from aspect ratio and area effects. Low order models were primarily used to conduct the bird flight study, though experimental methods were investigated as well. The thunniform swimming study was conducted through experimentation on a biomimetic system. The flight study found that, under the right circumstances, both wing twist and wing folding have a positive effect on flight performance. However, the impact of wing twist is much larger. To incorporate this wing twist into a robotic system, a new reduced order model that partially accounts for 3D effects was developed and validated. In the future, this model can be used in conjunction with a flight controller to control wing twist. The swimming study found that caudal fin sweep had a significant impact on performance, moderately swept fins showing the greatest improvement. Using an overly large sweep angle led to diminished performance when compared to the moderately swept fins, but still demonstrated improved performance over a non-swept fin. The increased performance of the moderately swept fins was due to how it affected LEV formation and stability. / Ph. D.

published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

Posthatchling green (Chelonia mydas) and loggerhead (Caretta caretta) turtles overlap ecologically but differ morphologically. This study compared hydrodynamic stability between the two species during swimming to test for functional differences in body shape. Flipper movement paths, four stability measures (yaw, pitch, heave, and sideslip), and the relative positions of the centers of buoyancy and gravity were compared between species. Both centers of buoyancy and gravity lie in the anterior body; their positions relative to one another differed with species, but showed no functional consequences. Neither species demonstrated substantial yaw, sideslip, or pitch. Both experienced upward heave with the flippers' downstroke and downward heave with the upstroke; however phase relationships differed between these limb and body motions. No differences were found between the two species. Despite obvious morphological differences, loggerheads and green turtles were similarly stable during swimming, suggesting that the species use different mechanisms to achieve stability. / by Erin Dougherty. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

This thesis presents a method for determining range of body motion for a walking machine with feet fixed on the ground. The darkling beetle was selected as the sample subject in this study. A closed form inverse kinematic solution is used to determine if a point in space is within range of body motion. An algorithm for tracing workspace boundary is also presented. The software, developed in Microsoft QuickC, has three main parts: (1) a module for searching the workspace contours and recording the contour points, (2) a plotting program for presentation of the workspace on the screen, (3) a module to determine ranges of roll, pitch and yaw for specified foot positions. The plotting program shows four views of the workspace, including front, top, and side views, and user specified axonometric projection. Body range of motion for a representative set of foot positions is presented and analyzed. Results are presented for normal resting height (10mm) and for 8mm and 12mm heights. Body range of motion for feet positioned for the alternating tripod gait is also presented. Ranges of roll, pitch and yaw have been determined and are discussed. / Graduation date: 1991

Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy