This project aims to use a variety of techniques to create a high performance system for relatively low cost, on a short build schedule. Taking inspiration from several different sounding rocket configurations, the Super Dart aims to achieve an altitude of 32 km, and a maximum velocity of 900 m/s. Early design inspiration primarily comes from the Loki Super Dart. Designed in the early 1960’s, the Loki sounding rocket consists of a 4.5 in diameter booster, which burns out at 5000 ft, moving at Mach 5, after which an unpowered 2 in dart separates and coasts to 340,000 ft due to low drag, high inertia and extreme velocity. Applying the techniques that streamlined the Loki, the Super Dart is a multistage powered dart. Using two boost stages takes advantage of the exponentially decreasing atmosphere to improve output from the motors, and avoids the difficulty and cost of larger engines. Powering the dart adds more thrust and inertia. To decrease cost from individual components and ensure reliable performance, we use off-the-shelf motors and components. Despite using pre-made components, a significant portion of constructions was left, from fabricating carbon-fiber and Kevlar enforced fins, to integrating motors and building custom electronics. The boost portion of the rocket will deliver 22 kN-s of impulse to the rocket, and boost it to 8500 m and 600 m/s, where the dart will separate. After separation and a brief coast, the dart motor will ignite, providing a final 1000 N-s of impulse, coasting to apogee 60 s after final burn-out, and 90 s after lift-off. To control the flight events, a custom flight computer was designed and implemented. Additional functions acquiring and relaying flight and GPS data in real-time. The Super Dart aims to be the highest and fastest rocket ever launched by the UW, and will be tested at Black Rock, NV. in March 2015.

Traditional manufacturing processes for high altitude rockets are time consuming and vulnerable to a high degree of human error. Currently, in Professor Robert Winglee's Rockets and Instrumentations lab, a rocket and its scientific payload can be built in ten weeks but without a guarantee that the system will have a successful flight. Additive manufacturing is the process of joining materials to create a 3D model (i.e. 3D Printing). With the rise of 3D printing in the public conscience, and the variety of new printer filaments coming on to market, incorporating additive manufacturing processes into our build cycles could benefit high altitude rocketry research. With 3D printing, we are able to build multiple rocket frames and internal components in a fraction of the time as traditional processes and with fewer labor hours. For this research project, we tested the viability of Polyactic Acid (PLA) filament printed rocket airframes for transonic flights. We used Kilo print, a large format 3D printer built by the WOOf 3D printing club on the University of Washington campus. The airframe has embedded sensors to record data on stress, strain, flex, and temperature. This data, combined with a flight post-mortem has helped us determine if PLA printed rocket components are viable for future flights. The rocket, nicknamed Ctrl+P, was launched in late April from the Black Rock Desert in Nevada. 

Hypoxemia, abnormal heart rate, and high capillary refill time are all signs of poor health. There is currently no single device that can evaluate all three key vital signs. We developed algorithms and explored the potential to measure these signs with conventional pulse oximetry finger clips consisting of two LEDs on one side (red and infrared) and a light sensor on the other side. We took a retired pulse oximetry finger clip, fit it with our hardware, and used an Arduino microcontroller and MATLAB software on a computer to process the data via a serial connection. The ratio of red to infrared light transmitted through the pulsatile blood was used to calculate the concentration of hemoglobin in the arteries, following modern pulse oximetry methods. The heart rate was analyzed with our custom spatial and frequency domain signal processing. The capillary refill time was measured by pressing and releasing the finger, and measuring the time it took for the transmitted light to return to pre-pressure levels. The system was able to resolve blood pulsatile changes in the red and infrared wavelengths. Initial testing on healthy controls revealed reasonable accuracy for pulse oximetry, high accuracy and precision for pulse rate, and high fidelity for the novel measurement of capillary refill time. Additional work is necessary for calibrating the device for pulse oximetry measurements. Likewise, further testing is required to fully characterize system performance. We constructed a prototype device and demonstrated initial feasibility for measurement of blood oxygenation, heart rate, and refill time. Because of the low cost of the materials involved and the improved accuracy of the sensor, this device could be a useful tool for hospitals in diverse locations.