Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1996. / Includes bibliographical references (p. 103-106). / by James Wallace Duda. / M.S.

Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (page 31). / In this thesis, I tested methods of adhering factory-made drip emitters to the interior of short segments of piping. Different types of adhesive and pipe material combinations were tested, and I selected three combinations for further testing. Performance similar to factory-installed drip emitters was achieved at low pressure, but the necessary watertight seals repeatedly burst at higher water pressures. Alterations to the drip emitter and installation procedure are recommended to increase reliability and resilience of the installation. / by Eric Johnson. / S.B.

Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references. / Water leaks pose a major problem of efficiency and cost to municipalities and industries that cover significant area. While current commercial methods to address these problems do not provide convenient or low cost methods to detect leaks, a soft-body pipe leak detection robot has been developed to traverse small, 50mm diameter water pipe systems. This robot has proven to be effective in small diameter pipes, but its scalability for large diameter pipes is unknown. The focus of this thesis is to scale up the leak detection robot for 300mm diameter pipes and fabricate a robot prototype. In particular, the relationship between the shape of the robot and its maneuverability was explored, such that it was designed to passively travel through the pipe, driven by water flow. The robot was designed to successfully pass through changes in pipe diameter, pipe bends, and through partially clogged regions. To detect and distinguish pipe leaks from other debris in the pipe, two sensors were integrated in the robot. Experimental testing was conducted with the robot to verify functionality of its leak detection sensors. Supporting electronics were also implemented to wirelessly charge and communicate with the robot. / by Kyle Scott Saleeby. / S.B.

Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Thesis. 1972. Sc.D. / MICROFICHE COPY ALSO AVAILABLE IN BARKER ENGINEERING LIBRARY. / Vita. / Includes bibliographical references. / Sc.D.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008. / Includes bibliographical references (leaf 20). / Between the years of 1953 and 2005, there were 253 fatalities from rappel failure/error. Some of these deaths may have been prevented if a stopper knot was tied at the end of the rope. Current climbing habits do not reinforce the tying of a stopper knot. More people are learning to climb in the gym and do not know risk reducing habits when beginning to climb outside, such as tying a stopper knot. The Hedgehog is a silicon device that reinforces the risk reducing habit of tying a stopper knot by a combination of form and color. A specially designed form aids in correct knot tying and the color signals the climber their attention is needed. When the Hedgehog was given to climbers in a climbing gym and had a success rate of 70%. Climbers without the Hedgehog had a success rate of only 8%. Success was defined as having a stopper knot in the rope when the climber began to ascend the route. / by Shane M. Treadway. / S.B.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 50). / In many biological systems, small rigid parts are embedded in deformable tissues to perform different biological functions. This study examines the effects of adding rigid filler particles inside deformable material. More specifically, a series of experiments led to eventual understanding of the relationship between effective Young's Modulus of material and volume fraction of rigid particles. The deformable material used in this study is gelatin, a readily available consumer product. It was found that the higher the volume fraction, the higher the Young's Modulus value for the composite material. In addition, it was found that cyclic loading with high strain and high volume fraction may cause stress stiffening or stress softening, while cyclic loading with small strain and small volume fraction yields linear elastic behavior. Furthermore, the effect of strain rate on material behavior was examined. Unfortunately the sample size was too small to draw definite conclusion. Finally, the reusability of particles was explored, and the results suggested that particles in composites are reusable so long as the composite did not undergo high strain compression. / by Kamyin Cheng. / S.B.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (p. 215-233). / The focus of this research was to develop a process suitable for creating very high resolution conductive patterns on polymer substrates, in a way that can be scaled to high volume manufacturing. The original motivation for this work came from the problem of manufacturing electrodes on microfluidic devices (which in volume production are commonly formed from polymers), but the findings of this work also have applications in flexible electronics, optics, surface patterning, organic micromanufacturing, and photovoltaics. After an initial exploration of various micromanufacturing processes, microcontact printing (μCP) was chosen as the most promising technique for further study. By using μCP to directly pattern conductive inks, this work has demonstrated previously unachievable printing: feature sizes down to 5μm, using liquid inks on polymer substrates, with a process that can be scaled to high-volume production. An understanding of the mechanisms of direct liquid ink transfer was used to identify relevant process input and output factors, and then the process sensitivities of those factors were investigated with a careful design of experiments. From the empirical data, a process model was built with generalized variables. This model was then used to successfully predict behavior of other inks and other substrates, thus validating the model and showing that it is extendable for future work. By developing an empirically verified model of ink transfer at the micron scale, this work has enabled a process for low cost, high volume microfeature patterning over large areas on polymer substrates. / by Melinda Hale. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (leaves 92-94). / by Kristie Yu. / S.M.

Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 48-49). / Traditional sources of UVC light for absorption spectroscopy are bulky, inefficient, and output tens to hundreds of watts of heat. In this paper we present the relative merits and disadvantages of using AIN based UVC emitting LEDs for absorption detection in liquid chromatography systems compared to traditional sources. We present the optical design for a detector based on a modular LED architecture and employing a digital micromirror device to modulate the light used in detection. The expected capabilities of a detector employing the design are derived and then compared to existing UV absorption detectors for liquid chromatography. The strategy presented in this paper holds significant advantages over existing detectors, including increased resolution and dynamic capabilities / by Daniel P. Gillund. / M. Eng. in Manufacturing

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1996. / Includes bibliographical references (p. 132-137). / by Ka Shun Wong. / Ph.D.