Multi-layer circuit boards are expensive; each additional layer significantly increases their production cost, however multiple layers are commonly necessary to avoid routing conflicts. Due to the large number and high density of pins on some components, a design issue is determining the minimum number of layers required to resolve all routing conflicts. Some buses must be assigned to consecutive layers, which add further complexity to the routing problem. We propose an improvement to an algorithm based on branch-and-bound for designing an optimal layer assignment for printed circuit board (PCB) bus escape routing. We use concepts from vehicle routing and scheduling algorithms to efficiently traverse the branch-and-bound tree. Our algorithm is guaranteed to provide a feasible layer assignment for each bus with the minimum number of layers.

High powered rocketry has a problem. Many individuals looking to deliver large payloads into the atmosphere have restrictive budgets. This project’s solution is a cluster rocket. These are rockets which use a group of smaller motors to deliver the same thrust as a larger motor. However, these smaller motors cannot deliver thrust for the same amount of time as the larger motors, resulting in a lower maximum altitude. A logical solution is a cluster rocket off another cluster rocket. In this study, an eleven motor cluster-on-cluster rocket is being designed with this in mind. This means that the rocket first fires seven motors simultaneously. After these motors have spent their fuel, the section containing them drops away and a second set of cluster motors fires. This more than doubles the maximum altitude of a single stage rocket. Because a rocket like this has never been launched at UW before, several experimental parts were designed for it. These include a flight computer a sixth the size of a traditional one, an internal cluster motor mount, and a transition capable of reinforcing a body tube internally. In order to complete this project, we utilized a wide variety of materials and construction techniques, from wet-lay carbon fiber to Kevlar to Popsicle sticks. We also put together one of the largest teams devoted to a single rocket, with members in the ME, AA, EE, IE, HCDE, and physics departments. This prototype was launched in March at Black Rock, NV and saw a reasonable amount of success. All motors ignited coming off the pad and the rocket maintained structural integrity until the recovery system on the first stage failed and it crashed. The second stage was recovered with no damage and will continue to be used as an example in the construction of internal clusters.

Tension variations are caused principally by composition (and sometimes temperature) variations from point to point on the interface. Unbalanced tension in the interface propels it into motion directed from the region of low tension toward the region of higher tension. The variations in interface composition and/or temperature leading to the Marangoni effect may develop in two different ways: either through the self-amplification of small disturbances (instability) or from macroscopic asymmetry in the system. In the presence of a surfactant, the disturbances in the adjoining bulk phases are resisted. The resulting elastic-like behavior is referred to as “Gibbs elasticity.” The mass transfer of acetic acid was examined in isobutanol-water and toluene-water systems. Also, the macroscopic asymmetry in a propanol-water system was observed. Finally, different concentrations of sodium dodecyl sulfate were examined to maximize the observation of Gibbs elasticity. To observe this phenomenon the schlieren system was utilized. The schlieren method of observation takes advantages of the variations in refractive index accompanying mass transfer to render visible flow patterns. The systems under study were placed in a capillary slit and observed with the schlieren system. Marangoni convection occurred in the mass transfer of isobutanol and toluene to water. However, it was not observed in the mass transfer of acetic acid in water to toluene and isobutanol. At 35 vol% isopropanol in water, “wine tears” formed. The tears formed due to Marangoni convection in the macroscopic asymmetries of the system. However, at 95 vol% isopropanol in water, the Marangoni effect was not observed. This was due to the azeotropic behavior of isopropanol and water. At higher concentrations of isopropanol, water is more volatile. Due to its higher surface tension, Marangoni convection does not occur. Due to contamination, Gibbs elasticity was not observed with sodium dodecyl sulfate.

The purpose of this research is to formulate an accurate, reliable, and efficient procedure for calculating wind loads on rooftop mounted photovoltaic systems. Current standards do not have any code regarding solar panels because they are relatively new. We are currently performing an in-depth analysis of photovoltaic systems located on the rooftop of Hogue Hall at Central Washington University. Full scale wind tunnel testing will also be performed by the Institute for Business and Home Safety at their research center in Chapel Hill, South Carolina. Weak points of mounting systems are identified and presented. Reasons for past failure of solar panels were investigated using structural analysis. In order to give the greatest chance of destruction of racking systems, hurricane force wind speeds were assumed. This study is assumed to take place in worst-case scenarios. We hope to have our procedure included in ASCE 7-16.

To escape Earth's atmosphere, traditional high powered rockets require significant amounts of fuel. Rocket fuel is very expensive and often consumes a majority of the budget allotted for a rocket. In the 1950's James Van Allen used weather balloons to lift rockets to high altitudes and take early video of solar activity. This rocket-balloon system, nicknamed the Rockoon, is a potentially cost-efficient way of conducting high altitude sounding experiments and putting low mass payloads in low earth orbit. By launching from high up in the atmosphere, the rocket uses less fuel because the distance to the desired altitude is shorter and the atmosphere is less dense, meaning less drag on the rocket. While Van Allen and others, such as JP Aerospace, have had successful Rockoon launches, they have all been sounding rockets (i.e. the rocket does not enter orbit but comes down after reaching apogee). The long-term goal of our research project is to use our Rockoon system to deliver a payload into a shallow orbit around the Earth. The Rockoon system uses two weather balloons to lift a two-stage high powered rocket and electronics package to a significant height. The rocket is remotely fired from the ground and recovered using GPS and radio frequency transmitters. In March of 2014, the two-stage rocket prototype was launched from an altitude of 5,000ft at Black Rock, NV. The rocket had a maximum velocity of Mach 2.2 and reached an apogee of ~45,000ft. The next phase of our research is to do an untethered launch at 100,000ft using a thermally insulated sounding rocket. By improving upon future iterations of the Rockoon, we can develop a system and instrumentation that can be used by a variety of professionals and amateurs as an affordable and faster method for delivering payloads to space.

Cyanide-bridged transition metal complexes serve as model systems to study photoinduced charge transfer reactions. These complexes are important to understand because they play a major role in processes such as photosynthesis and the conversion of light to electronic energy in solar cells. Using RuCl₃•XH₂O salt, 2,2':6',2"-terpyridine (tpy), 2,2'-bipyridine (bpy) and KCN we synthesized [Ru(tpy)(bpy)CN]²⁺, [(tpy)(bpy)Ru-{CNRu(tpy)(bpy)]³⁺ and [(bpy)₂Ru-{CNRu(tpy)(bpy)]⁴⁺. These multistep syntheses were monitored using FTIR, UV-vis and ¹H NMR in order to verify that the compounds of interest were made. These compounds are interesting because of their metal-to-ligand charge transfer and metal-to-metal charge transfer processes when excited with visible light.  In the future these complexes will be studied using nonlinear spectroscopies in the visible and infrared regions of the spectrum in order to investigate their charge transfer capabilities.

Plasma, the fourth state of matter, makes up over 99% of the visible universe.  However, plasmas have so far found few applications, the most notable of which include fluorescent lights, fusion energy, and space propulsion.  Plasma researchers believe that the scarcity of plasma applications is due to the difficulty in controlling plasmas; therefore, obtaining a true control of high temperature, high density plasmas will likely spur on a plethora of new plasma applications.  At the University of Washington, the ZaP Flow Z-Pinch Experiment is one of many research labs studying high desnity plasmas in order to both create and aid the development of plasma applications.

This presentation will include both a discussion of the problems confronting the development of plasma applications and an overview of the presenter's work in developing spectroscopy analysis--the analysis of light spectra emitted by impurity ions in the ZaP experiment to determine the characteristics of controlled plasmas--as a primary tool towards obtaining an understanding of plasmas that promotes innovation.