Date of Award

Spring 2014

Degree Type


Degree Name

Master of Science (MS)


Mechanical Engineering

First Advisor

James F. Doyle

Committee Member 1

Jun Chen

Committee Member 2

Marisol Koslowski


Impact among soft structures is often difficult to model because of the geometrical non-linearity involved. There are a number of previous studies of the contact dynamics of rigid bodies, but few has focused on soft structures so far.

This thesis models impact between soft structures without any restraint on their geometries. The goal is to simulate the dynamics involved among soft structures during an impact process. This has been done through designing and implementing an contact algorithm that uses the finite element method along with a three-dimensional solid element to solve the fundamental time integration problem. Modeling of the contact force is the core part and major challenge for the design of the algorithm. In general, the contact algorithm has been implemented in a clear and easy-to-understand style and the program features a comprehensive list of output and its compatibility with other service programs within the same simulation environment

Three test systems have been designed to check the robustness of the algorithm. Although these testing systems can not represent all kinds of structures in the real world, the design of them ensures that they're able to represent a number of generic cases where soft structures come into contact. The results have shown that the algorithm designed works very well in terms of handling these impact systems.

The algorithm developed here has been validated under some generic cases, but it's just a start and there are still much work remained to be done for the perfection of it. Details of some improvements are discussed at the end of this thesis.