Chung, Philip, Heller, J Alex, Etemadi, Mozziyar, Ottoson, Paige E, Liu, Jonathan A, Rand, Larry, and Roy, Shuvo
Journal of visualized experiments : JoVE, iss 88
Vagina, Humans, Silicone Elastomers, Equipment and Supplies, Computer-Aided Design, Female, Printing, Three-Dimensional, Bioengineering, Issue 88, liquid injection molding, reaction injection molding, molds, 3D printing, fused deposition modeling, rapid prototyping, medical devices, low cost, low volume, rapid turnaround time, Cognitive Sciences, Biochemistry and Cell Biology, and Psychology
Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.
Històries de vida, Discapacitat visual, Educació artística, Prototipatge ràpid, Ceguesa, Impressió tridimensional, Life history, Visual impairment, Art education, Rapid prototyping, Blindness, 3D printing, Historias de vida, Discapacidad visual, Educación artística, Prototipado rápido, Ceguera, and Impresión tridimensional
The construction of this thesis is developed from different conceptual interlacing axis that created a networking weave through which the field of investigation was debated and defined and a project of collaborative citizenship with the goal of providing an improvement in the social environment from which the visual impairment through art was built. Firstly, we speak about the context in which, in a dialogic way, the identity of Ph. D. Rosa Gratacós Masanella has grown and developed. With the help of the narrative research and the life story methods we make an approach to the life time experience of the main character of our investigation, in order to understand her social, political and educational context, how it relates to her personal life, her work as a professor and her artistic career, and how all these different perspectives have points in common. We also approach those people who met our protagonist, those who were her referents or were important in the evolution of her identity. We point Ph. D. Rosa Gratacós pioneer investigation in the field of visual impairment and we finally explain the multisensory project of The Senses Labyrinth, a project that was born from the idea of universal accessibility from the perspective of blind people. Sensory education, game and art become the source of teaching and learning for the researcher and they are applied together to art education and artistic perception from blindness, through service and learning methodologies
Chepelev, Leonid, Giannopoulos, Andreas, Tang, Anji, Mitsouras, Dimitrios, and Rybicki, Frank J
3D printing in medicine, vol 3, iss 1
3D printing, Additive manufacturing, Data integration, Freeform fabrication, Medicine, Rapid prototyping, Standards, and Terminology
Background:Medical 3D printing is expanding exponentially, with tremendous potential yet to be realized in nearly all facets of medicine. Unfortunately, multiple informal subdomain-specific isolated terminological 'silos' where disparate terminology is used for similar concepts are also arising as rapidly. It is imperative to formalize the foundational terminology at this early stage to facilitate future knowledge integration, collaborative research, and appropriate reimbursement. The purpose of this work is to develop objective, literature-based consensus-building methodology for the medical 3D printing domain to support expert consensus. Results:We first quantitatively survey the temporal, conceptual, and geographic diversity of all existing published applications within medical 3D printing literature and establish the existence of self-isolating research clusters. We then demonstrate an automated objective methodology to aid in establishing a terminological consensus for the field based on objective analysis of the existing literature. The resultant analysis provides a rich overview of the 3D printing literature, including publication statistics and trends globally, chronologically, technologically, and within each major medical discipline. The proposed methodology is used to objectively establish the dominance of the term "3D printing" to represent a collection of technologies that produce physical models in the medical setting. We demonstrate that specific domains do not use this term in line with objective consensus and call for its universal adoption. Conclusion:Our methodology can be applied to the entirety of medical 3D printing literature to obtain a complete, validated, and objective set of recommended and synonymous definitions to aid expert bodies in building ontological consensus.
Materials Science, Biomedical engineering, Chemical engineering, 3D Printing, Elastomer, Hydrogel, Mechanical Properties, Polyurethane, and Tissue Engineering
Understanding the physical and chemical properties of biomaterials in rapid 3D printing could pave a way for the construction of complex structures with specific functionalities. Both the material conditions and printing techniques play crucial roles in modulating these properties. This dissertation was dedicated to answering the basic questions about how to engineer and improve the mechanical performance of rapidly 3D printed structure from synthesis and printing process. Three distinct groups of materials, namely plastic, soft hydrogels, and elastomeric polymers were used as case studies to reveal their relationships. Additionally, the toughening mechanism of networks with different mechanical properties was discovered and tested. These results could help future studies in rapid prototyping of medical devices, as well as adapting 3D printing in tissue engineering as a new direction.
Mechanical engineering, 3D Printing, Control, Design, Fingerprint, Medical, and Soft Robotics
In this work, I explore two facets of manipulation of delicate objects. First I describe the development of a new closed system for differential pressure control of 3D printed soft fluidic actuators. I further explore the quantitative advancements it promises for soft robotics towards a robotics manipulator capable of safely and efficiently manipulating infant’s fingers. Secondly, we present the development of a biometrics system for vaccinations which requires manipulation and imaging of infants’ fingers. The fingerprinting process could highly benefit from automation solutions for infants’ fingerprint platen induced deformation due to contact. The next aspect of my thesis is the experimental approach for iterative testing in technology design. Starting with the volumetric control platform developed to enable accurate iterative testing in laboratory settings for experimental characterization of soft actuators with differential pressure control. In this work, I demonstrated a substantial improvement in achievable blocked force, and a significant increase in actuator workspace when using differential pressure actuation as compared to the use of only pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks towards manipulation of fragile objects. Furthermore, I demonstrate a self-healing capability of the combined system for improved soft robotics robustness. Then I follow with an approach for human-centered design with iterative prototyping where experiments can only be performed in situ with live infant subjects. This separation between the design and experiments yields a very challenging progress evaluation and required a unique design iteration methodology. With the resulted fingerprints images from the two leading devices, I demonstrated a higher reliability for high quality infants’ fingerprints using non-contact imaging over contact in the goal of developing a reliable biometrics identification system of infants for vaccination.
Engineering, Biomedical engineering, 3D printing, Automation, Bioengineering, Engineering, Instrumentation, and Sensor development
We demonstrate a simple and inexpensive sensor capable of weighing microgram- scale objects in fluid. When objects flow through a glass tube that is vibrating at its resonance frequency, the frequency changes by an amount that is inversely proportional to the object’s buoyant mass. By measuring this frequency change, microgram objects can be weighed in fluid with nanogram-scale resolution. These sensors are easily fabricated, require no labels or tags, and are versatile, making them a valuable instrument for both in situ and laboratory measurements. They are fully automated and can measure any appropriately sized object in a wide range of biological, physical, and chemical applications. Using resonating glass tubes, we demonstrate the mass change detected in zebrafish (D. rerio) embryos as they are exposed to various toxicants, the water uptake and germination of dry seeds as they are put in water, and degradation rates in biomaterials in different fluid media.Aside from the experimental data from two separate resonator geometries, we also present simulations on other geometries that can be explored for these sensors. We explore the advantages and disadvantages in each geometry and potential sources of measurement error associated with the resonators. The simulations allow us to predict the resolution and the quality factor of the resonator before a prototype is developed.We took advantage of various rapid prototyping techniques, including 3D printing for developing these sensors. In this process, we discovered that 3D printed parts produce a toxic effect in zebrafish embryos. This observation led to a separate project, in which we assessed the toxicity of printed parts from two main classes of commercial 3D printers, fused deposition modeling and stereolithography. We used zebrafish embryos, a widely used model organism in aquatic toxicology and monitored them for rates of survival, hatching, and developmental abnormalities. We found that parts from both types of printers were measurably toxic, with STL-printed parts significantly more toxic than FDM-printed parts. We also developed a simple post-printing treatment (exposure to ultraviolet light) that largely mitigates the toxicity of the STL-printed parts. Our results call attention to the need for strategies for the safe use and disposal of 3D-printed parts and printer waste materials.
Materials Science, Mechanical engineering, Biomedical engineering, 3D Printing, Bioassay, ELISA, Fused Deposition Modeling, Manufacturing, and Stereolithography
Fabrication of a microfluidic ELISA assay can be a very time-consuming method, due to the curing process required for molded parts. This thesis examines Fused Deposition Modeling and Stereolithography as candidates for rapid prototyping microfluidic devices. Individual components of the device were designed on SolidWorks, and underwent several generations of revisions to address problems of air and fluid leakage. We present an automated ELISA assay device created using a combination of Fused Deposition Modeling and Stereolithography as a comprehensive demonstration of additive manufacturing capabilities, as well as the methodology used to create such a device. A detailed explanation on how to troubleshoot the fabrication process and machines is also discussed.