SUBJECT: M.S. Thesis Presentation
BY: Patrick Chang
TIME: Friday, June 10, 2011, 9:00 a.m.
PLACE: MARC Building, 201
TITLE: An Improved Size, Matching, and Scaling Method for the Design of Deterministic Mesoscale Truss Structures
COMMITTEE: Dr. David W. Rosen, Chair (ME)
Dr. Christiaan Paredis (ME)
Dr. Seung-Kyum Choi (ME)


Mesoscale truss structures (MSTS) are a type of cellular structure with support element sizes on the order of magnitude of centimeters. These types of structures are engineered for high performance and have applications in industries where both low weight and high strength are desired. However, due to the small size of their struts, MSTS can easily have thousands of individual struts. Current methods approach design of MSTS as an optimization problem, treating each strut diameter in the structure as a design variable. These optimizations are time-consuming and are generally the main bottleneck in the design of MSTS. In previous research, a highly efficient design method for MSTS was presented that eliminates the need for global size or topological optimization. This method, termed the Size, Matching and Scaling (SMS) method, used a unique combination of a solid-body finite element analysis and a library of pre-defined lattice configurations to generate lattice topologies. The results from this method were highly promising: design time was significantly reduced and structural performance results were comparable with results from optimization methods. However, the method developed was highly conceptual, lacking a true systematic methodology for generating topologies and suffering from some gaps in implementation. In this research, we present a modified SMS design method. Firstly, we introduce the modified methodology. This methodology particularly includes an optimization step for determining strut diameters that replaces the manual search used in the original method. Secondly, we expand and explore the unit-cell library in an attempt to improve the performance of lattices generated using the SMS method. In particular, we optimize several additional unit-cell configurations and compare their performance in the context of the SMS method. Finally, we test the updated SMS methodology and unit-cell library using various design examples.