AbstractsComputer Science

This dissertation investigates a new medical device design approach based on extensive simulations. A simulation-based design framework is developed to create a design workflow that integrates engineering software tools with an interactive user interface, called Design by Dragging (DBD) \cite{Coffey:2013ko}, to generate a large-scale design space and enable creative design exploration. Several design problems illustrate this design workflow are investigated via featured forward and inverse design manipulation strategies provided by DBD. A device-tissue interaction problem as part of a vacuum-assisted breast biopsy (VAB) cutting process is particularly highlighted. A tissue-cutting model is created for this problem to simulate the device-tissue contact, excessive tissue deformation and progressive tissue damage during the cutting process. This model is then applied to the design framework to generate extensive simulations that samples a large design space for interactive design exploration. This example represents an important milestone toward simulation-based engineering for medical device prototyping. The simulation-based design framework is implemented to integrate a computer aided design (CAD) software tool, a finite element analysis (FEA) software tool (SolidWorks and Abaqus are selected in this dissertation) and a high performance computing (HPC) cluster into a semi-automatic design workflow via customized communication interfaces. The design framework automates the process from generating and simulating design configurations to outputting the simulation results. The HPC cluster enables multiple simulation job executions and parallel computation to reduce the computation cost. The design framework is first tested using a simple bending needle example, which generates 460 simulations to sample a design space in DBD. The functionality of the creative inverse and forward design manipulation strategies are demonstrated. A tissue cutting model of a VAB device is developed as an advanced benchmark example for the design framework. The model simulates the breast lesion tissue being positioned in a needle cannula chamber and being cut by a hollow cutting tube with simultaneous rotation and translation. Different cutting conditions including cutting speeds and tissue properties are investigated. This VAB device design problem is then applied to the design framework. Critical design variables and performance attributes across three main components of the VAB device (the needle system, motor system and device handpiece) are identified. 900 design configurations are generated and simulated to sparsely populate a large-design space of $10^6$ possible solutions. The design space is explored via the creative design manipulation strategies and several uses cases are established. The bending needle example demonstrates the first success of the proposed simulation-based design framework. The 460 simulations are completed with minimal manual interventions. The functionality of DBD is also demonstrated. The inverse and forward…