Material Coefficient of Thermal Expansion Investigation for Use in Additive Manufacturing Fused Deposition Modeling for Composite Tooling

Polymer matrix composites are being used to manufacture light weight, high stiffness aircraft structures. These structures are often manufactured from carbon fiber reinforced epoxy. When these structures are damaged, they must be repaired to restore strength to the component to avoid the cost and logistics of having replacements parts. Occasionally, these repairs require tooling in order to make a quality repair, however, tooling generally has a long lead time. Additive manufacturing could be used to manufacture rapid tooling to create tooling for composite repairs. The issue is that polymer printed tooling has a much higher coefficient of thermal expansion (CTE) than the composites that are being cured on them. This research investigates the addition of negative CTE fillers in polymers to reduce CTE to more closely match composites to reduce CTE mismatch and part distortion during elevated temperature cure

Assessment of fouling in native and surface-modified water purification membranes

textFouling is a major obstacle to the implementation of membranes in water purification applications. Hydrophilization of the membrane surface tends to mitigate fouling because hydrophobic interactions between foulants and the membrane are reduced. Polydopamine was deposited onto membranes to render their surfaces hydrophilic. The chemical structure of polydopamine, which was previously ambiguous, was investigated by many spectroscopic techniques. While previously thought to consist of covalently-linked monomers, polydopamine was found to be an aggregate of partly-oxidized dopamine units linked by strong, non-covalent secondary interactions. Polydopamine was also used as a platform for the molecular conjugation of other anti-fouling materials, such as poly(ethylene glycol), to the membrane surface. Membrane fouling was assessed by constant permeate flux crossflow filtration with an oil/water emulsion feed. The threshold flux--the flux at which the rate of fouling significantly increases--was determined by a well-established flux stepping technique. Membrane resistance evolution during fouling was compared for constant flux and constant transmembrane pressure operation using unmodified membranes. Below the threshold flux (slow fouling), good agreement in resistance evolution was found between the two operational modes; above the threshold flux, significant deviation was observed. The effect of polydopamine and polydopamine-g-poly(ethylene glycol) surface modifications was studied under constant flux crossflow fouling conditions. The surface modifications were found to increase the membrane resistance, resulting in higher transmembrane pressures in the modified membranes than in the unmodified membranes at fluxes below the threshold flux. Modified membranes were also compared to unmodified membranes with the same pure water permeance (same initial resistance). In this case, the modified membranes had lower transmembrane pressures during fouling than the unmodified membranes, suggesting that a preferred method of membrane surface modification is to begin with a membrane of higher permeance than required, and then surface-modify it to achieve the desired permeance. The efficacy of polydopamine and polydopamine-g-poly(ethylene glycol) surface modifications in reducing biofouling was also evaluated. Modified membranes showed reduced protein and bacterial adhesion in short-term tests, which are commonly used to assess biofouling propensity. However, long-term operation under hydrodynamic conditions mimicking those of an industrial module showed no benefit of the hydrophilic coatings in limiting biofouling.Chemical Engineerin

Education Through Visualization: Designing a Year 12 Chemistry Educational Program

In conjunction with the Commonwealth Scientific and Industrial Research Organisation (CSIRO), the team delivered a set of recommendations for the development of a new 3D biomolecule education program targeted towards year 12 chemistry students. To generate these recommendations, the team conducted interviews and surveys of local VCE teachers, reviewed previous VCE Exams, and investigated Visual Molecular Dynamics and its various features. We determined the specific topics of biomolecules that students struggled with and how animations would be able to help. Ultimately, our recommendations will help develop a program that will make complex concepts of biochemistry more accessible to students and educators alike

Waterborne Autonomous Vehicle

This project designed and realized the Waterborne Autonomous VEhicle (WAVE), a submersible modular robotic platform to enable research on underwater technologies at WPI at minimal cost. WAVEÂ’s primary design objectives were modularity and expandability while adhering to the regulations for the international competition held by the Association for Underwater Vehicle Systems International. WAVEÂ’s core features include a six degree-of-freedom chassis, a modular electronic infrastructure, and an easily configurable software framework

Waterborne Autonomous VEhicle

This project designed and realized the Waterborne Autonomous VEhicle (WAVE), a submersible modular robotic platform to enable research on underwater technologies at WPI at minimal cost. WAVEÂ’s primary design objectives were modularity and expandability while adhering to the regulations for the international competition held by the Association for Unmanned Vehicle Systems International. WAVEÂ’s core features include a six degree-of-freedom chassis, a modular electronic infrastructure, and an easily configurable software framework

Dyno-Mite Redesign

The Cal Poly Mechanical Control Systems Laboratory currently employs an outdated device, known as the Motomatic, to teach students about various motor characteristics and control methods. These include open-loop vs. closed-loop control, speed vs. position control, and DC motor response curves. The current device does not function properly and produces unreliable data due to overwhelming non-linear effects such as stiction and shaft misalignment. Our team was tasked with designing a replacement device that retains many of the same educational goals as the original lab procedure, while also adding new educational goals pertaining to the device system dynamics. The new apparatus, dubbed the Dyno-Mite is a one tenth scale tire testing machine, incorporating two DC brushed motors, adjustable mechanisms, and load cell measuring devices. The design will also pay special attention to modularity so that future adjustments and modifications can be made to the lab apparatus, allowing for instructors to tailor the machine to meet their specific educational goals

Grist: Grid-based Data Mining for Astronomy

The Grist project is developing a grid-technology based system as a research environment for astronomy with massive and complex datasets. This knowledge extraction system will consist of a library of distributed grid services controlled by a work ow system, compliant with standards emerging from the grid computing, web services, and virtual observatory communities. This new technology is being used to find high redshift quasars, study peculiar variable objects, search for transients in real time, and fit SDSS QSO spectra to measure black hole masses. Grist services are also a component of the "hyperatlas" project to serve high-resolution multi-wavelength imagery over the Internet. In support of these science and outreach objectives, the Grist framework will provide the enabling fabric to tie together distributed grid services in the areas of data access, federation, mining, subsetting, source extraction, image mosaicking, statistics, and visualization