Engineering Commons^™

Characterization And Quality Assessment Of Smart Polymer Systems Fabricated By Using 3d Printing Technique, Carlos Alejandro Garcia Rosales

Open Access Theses & Dissertations

Shape memory polymers (SMPs) are classified as smart materials due to their inherent stimulus-induced response. SMP is capable of recovering its original shape from a high degree of deformation by applying an external stimulus such as thermal energy. Other stimuli are electricity, light, chemical, and magnetic field. Shape memory polymers (SMPs) and its fabrication process has recently attracted much attention as a result of their potential application as soft active materials. Demonstration of SMP systems fabricated via 3D printing technologies has been one of the most popular attempts. This Dissertation presents an integration of two commercial SMP materials (DiAPLEX and …

Master's In Electrical Engineering, Ricardo Xavier Rodriguez

Open Access Theses & Dissertations

This project is a focus on characterizing the process for actualizing three dimensional structures out of a carbon nanostructure composite via a direct print additive manufacturing process. Manufacturing parts additively enables for realization of geometrically complex shapes that often times cannot be manufactured any other way. The specificity of a material's properties have to be such, that the processing method can precisely place and bond material to itself in a highly repeatable manner. Commercial materials for additive manufacturing are have been optimized with these goals in mind and, therefore, often times lack the rigor and robustness for many applications.

The …

Manufacturing Nerve Guidance Conduits By Stereolithography For Use In Peripheral Nerve Regeneration, Mireya Aidee Perez

Open Access Theses & Dissertations

Nerve regeneration techniques have been studied in great depth in recent years. Peripheral nerve injuries, in particular, can be caused by accidents, falls, athletic injuries, etc. Current methods of repair include direct suturing of the 2 injured nerve ends or the use of autografts, when a nerve section is taken from another area of the body. Both methods have a series of limitations which have led researchers to study alternative methods of repair. Nerve guidance conduits may provide a viable solution because they can be modified and adapted to the patient's needs. Some conduits already exist on the market and …

3d Printing For The Rapid Prototyping Of Structural Electronics, Rodolfo Salas

Open Access Theses & Dissertations

In business, the time required to shepherd a new product through the phases of concept, design, prototypes, through manufacture and finally making the product available for sale (together known as: Time to Market) is critical to the success and profitability of the next generation of products. The use of relatively new technologies, known as 3D Printing, which allow the fabrication of complex tridimensional shapes within hours of a completed CAD design without the need for tooling or molds, has significantly reduced the time required for a designer to physically hold a part designed only hours before and to perform form …

Three-Dimensional Structural Electronic Integration For Small Satellite Fabrication, Cassie Gutierrez

Open Access Theses & Dissertations

The ability to realize truly three-dimensional electronic circuits is complicated if not impossible using traditional fabrication techniques. Such techniques are limited to the use of two dimensional printed circuit boards (PCBs), and require various dissonant processes which exhaust time, volume and cost. Due to the nature of Additive Manufacturing (AM) such problems are diminished and in some ways completely overcome. Additive Manufacturing allows for a higher range of design freedom along conformal surfaces, as well as unit level customization; it is the threshold for embedded electronics, allowing for three-dimensional circuitry in ways traditional fabrication is unfeasible. In such ways, additive …

Conformal Electronics Packaging Through Additive Manufacturing And Micro-Dispensing, Richard I. Olivas

Open Access Theses & Dissertations

Realizing electronic systems that are conformal with curved or complex surfaces is difficult if not impossible with conventional fabrication techniques, which require rigid, two dimensional, printed circuit boards (PCB). Flexible copper based fabrication is widely available commercially providing conformance, but not simultaneously stiffness. As a result, these systems are susceptible to reliability problems if repeatedly bent or stretched. The integration of Additive Manufacturing (AM) combined with Direct Print (DP) micro-dispensing can produce shapes of arbitrary and complex form that also allows for 1) miniature cavities for insetting electronic components and 2) conductive traces for electrical interconnect between components. The fabrication …

Automated Fluid Handling And Leveling System For Multiple Material Stereolithography, Yinko I. Grajeda

Open Access Theses & Dissertations

This work addresses the development of an automated multiple material fluid handling and leveling system for its implementation into a Multiple-Material Stereolithography (MMSL) apparatus. A patent filed by Wicker et al. (US Patent 7,556,490) disclosing a MMSL apparatus served as the basis for the development of this work. The system is designed to operate in a variety of MMSL apparatus configurations. Fluid vats are designed to meet the enclosure constraints, facilitate the interface to the pump and sensor, and support the handling of the fluids. Due to its fluid isolation and bi-directional flow capabilities, a digital drive peristaltic pump is …

Synthesis And Manufacture Of Photocrosslinkable Poly(Caprolactone)-Based 3d Scaffolds For Tissue Engineering Applications, Nathan Jonathan Castro

Open Access Theses & Dissertations

It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however, generally cause more trouble since the body is incapable of repairing them. Bone defects can occur as a result of congenital abnormalities, trauma, or disease. Traditional methods for addressing these defects have involved the use of acellular cadaverous bone or autologous bone. Both contain innate problems associated with them; the former method can result in disease transmission, as well as very low integration with the host …

Retrofitting A Stereolithography System Within A Laminar Flow Hood, Mahesh Pandurang Tonde

Open Access Theses & Dissertations

This research focused on retrofitting the stereolithography (SL), a rapid prototyping technology, inside a laminar flow hood to provide an aseptic, particulate-free environment for scaffold fabrication. Two of the important objectives of this project were to retrofit the commercial SLA 250/30 inside a laminar flow hood to demonstrate that the manufacturability of the Bio-SL system was comparable to original SLA 250 system and to conduct the sterility test on fabricated scaffolds to show that the laminar flow hood was able to provide an aseptic, particulate-free environment for the fabrication.

Exploring Poly(Ethylene Glycol) As A Suitable Material For Peripheral Nerve Regeneration Scaffolds Manufactured By Stereolithography, Nubia Zuverza

Open Access Theses & Dissertations

One of the challenges in tissue engineering is to have spatial and temporal control over the biological elements within a scaffold used to guide regeneration for example of transected nerves. Some of the physical and chemical characteristics to regulate include incorporation of bioactive domains and release of chemical signals. This study presents the use of stereolithography (SL) to incorporate localized domains for cell adhesion in addition to include releasable nerve growth factor (NGF) in the process of building poly(ethylene glycol)diacrylate (PEGda) hydrogel scaffolds. Besides providing sites for cell attachment, an ideal nerve guidance conduit (NGC) should be able to release …

Stereolithography Of Poly(Ethylene Glycol) Hydrogels With Application In Tissue Engineering As Peripheral Nerve Regeneration Scaffolds, Karina Arcaute

Open Access Theses & Dissertations

In recent years, rapid prototyping (RP) technologies initially developed to create prototypes prior to production for the automotive, aerospace, and other industries, have found applications in tissue engineering (TE). Several different RP technologies are being used to fabricate biocompatible 3D structures with controlled micro- and macro-scale characteristics. The focus of this research was to explore the capabilities of the RP technology, stereolithography (SL), for creating complex, 3D scaffolds with applications in TE using a photocrosslinkable biopolymer, poly(ethylene glycol) (PEG). The primary objective was to create an implantable multi-lumen nerve guidance conduit (NGC) for the regeneration of peripheral nerves.

Studies of …