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Abstract A study was conducted on three models of the medieval siege engine, the trebuchet. The three models analyzed were the "see-saw", the hinged, and the floating arm trebuchet. Of these models, the mathematical model of each was determined. With his model, the most efficient model was determined to be

Abstract A study was conducted on three models of the medieval siege engine, the trebuchet. The three models analyzed were the "see-saw", the hinged, and the floating arm trebuchet. Of these models, the mathematical model of each was determined. With his model, the most efficient model was determined to be the floating arm trebuchet, with a range efficiency of 0.8275 and an energy efficiency of 0.8526. The hinged trebuchet achieved efficiencies of 0.8065 for both range and energy efficiency and the "see-saw" with efficiencies of only 0.567 and 0.570, respectively. Then, the floating arm trebuchet's arm length ratio and sling length were then optimized. It was determined that the optimal arm length ratio was approximately 1:2, where the short arm is 1.7 feet and the long arm is 3.3 feet. The optimized sling length was 4.45 feet. Finally, the mathematical models were compared to full scale models. These ranges of the full scale models were surprisingly accurate with what was predicted. The hinged trebuchet model had the largest percentage error at 8.4%.
ContributorsEstes, Stephen Louis (Co-author) / Estes, Nathan (Co-author) / Liao, Yabin (Thesis director) / Trimble, Steven (Committee member) / Bucholz, Leonard (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2013-05
Description
The study of the mechanical behavior of nanocrystalline metals using microelectromechanical systems (MEMS) devices lies at the intersection of nanotechnology, mechanical engineering and material science. The extremely small grains that make up nanocrystalline metals lead to higher strength but lower ductility as compared to bulk metals. Effects of strain-rate dependence

The study of the mechanical behavior of nanocrystalline metals using microelectromechanical systems (MEMS) devices lies at the intersection of nanotechnology, mechanical engineering and material science. The extremely small grains that make up nanocrystalline metals lead to higher strength but lower ductility as compared to bulk metals. Effects of strain-rate dependence on the mechanical behavior of nanocrystalline metals are explored. Knowing the strain rate dependence of mechanical properties would enable optimization of material selection for different applications and lead to lighter structural components and enhanced sustainability.
ContributorsHall, Andrea Paulette (Author) / Rajagopalan, Jagannathan (Thesis director) / Liao, Yabin (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05