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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1171

The Winch-Bot : a cable-suspended, under-actuated robot utilizing parametric self-excitation / Cable-suspended, under-actuated robot utilizing parametric self-excitation

Cunningham, Daniel Philip January 2009 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009. / Includes bibliographical references (leaf 71). / A simple, compact, yet powerful robotic winch, called "Winch-Bot," is presented in this thesis. The Winch-Bot is an underactuated robot having only one controllable axis. Although hanging a load with merely one cable, it is capable of moving it in a large workspace by swinging the load dynamically based on parametric self-excitation. The generated trajectories can be used for a variety of tasks, from moving material to cyclic inspection of surfaces. The basic principle and design concept of the Winch-Bot are first described, followed by dynamic modeling and analysis. Two trajectory generation problems are solved. One is point-to-point transfer of a load, and the other is the tracking of a continuous path. It will be shown that the system can track a given geometric trajectory, although the tracking velocity cannot be determined arbitrarily due to the underactuated nature of dynamics. A prototype Winch-Bot is designed and built, and point-to-point, continuous path, and parametric excitation control are implemented. / by Daniel Philip Cunningham. / S.M.
1172

Harnessing waste heat and reducing wasted lighting : three mechanical structures for efficient energy systems

Stronger, Brad A January 2008 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 47-48). / This thesis presents three mechanical structures designed for efficient energy systems. In [3], Cooley presents a modification of a fluorescent lamp which allows it to detect nearby occupants and dim itself automatically. This modification presents marketability challenges, as a metal electrode must be suspended from the lamp, but one solution is to integrate an electrode holder into the bulb socket. We present one design for such an integrated electrode. Second, we discuss the creation of a homopolar motor to convert the low-voltage electrical power available from a thermoelectric wafer, which could be powered by waste heat. We are able to achieve brushes and bearings with electrical resistance as low as 70 m[Omega] and friction torque under 300 ,/N.m to demonstrate a proof-of-concept test setup. The demonstrated electromotive force constant is 82 V/rad/s using a 1 inch diameter, 5500 gauss magnet. Finally, we discuss the application of waste heat harvesting to household water heating, and discuss several designs for a water heater with integrated attachment points for waste heat producing devices. / by Brad A. Stronger. / S.B.
1173

Characterization of an oxygen suspension used for intravenous infusion

Peña, Kristen Helen January 2012 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 45). / Oxygenated fluid mixture can be used to treat critically ill patients suffering from asphyxia, lung injury, and cardiac arrest. This oxygenated fluid delivered intravenously re-oxygenates the bloodstream, allowing for more time to resuscitate a patient before they suffer brain and/or organ damage. The concentration of the mixture is crucial for treatment as it affects the viscosity of the fluid, which in turn affects how well the fluid mixes with blood and how long it takes for oxygen to diffuse out of it. Evaluating the quality of fluid delivered and characterizing oxygenated fluid mixture at different concentrations was paramount. Since the fluid is a non-Newtonian emulsion, delivering a specific flow rate is challenging due to the following effects: degradation, compressibility, and shear thinning. Therefore, a testing machine was developed to aid in understanding the fluid dynamic behavior of the oxygenated mixture. The quality of the fluid can be assessed through measurement of the volume percentage, particle size distribution, oxygen tension, and rheometry. The data collected from the experiments will serve to create a model for delivering a specific volumetric flow rate of the fluid at atmospheric pressure. / by Kristen Helen Peña. / S.B.
1174

Science fiction to science fact : the link between early science fiction and the space programs

White, Craig (Craig E.), 1971- January 1998 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1998. / Includes bibliographical references (p. 26-27). / by Craig White. / S.B.
1175

Improving operational efficiency of a semiconductor equipment manufacturing warehouse through strategic allocation of parts

Toor, Paramveer Singh January 2015 (has links)
Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (page 75). / The work addresses the operational inefficiency problem in a semiconductor equipment manufacturing warehouse of Applied Material's Varian Semiconductor Business Unit. At Varian, the target part delivery time from the warehouse to the production floor is 24 hours. However, during busy periods, parts are not delivered on time. Late part delivery from the warehouse to the production floor could delay the machine laydown date, which in turn could result in late or missed shipment of tools to the customers, which can be very costly. To improve the efficiency and the reliability of the warehouse, picking efficiency is to be improved. Parts from the warehouse are picked from three picking locations- Vertical Lift Modules (VLMs), GL, and RK. VLMs are automated machines, while GL and RK are manual picking zones. Picking an order from GL takes the most amount of time. The overall picking efficiency at the warehouse can be improved by partially shifting the workload from GL to the VLMs, and by further improving the picking efficiency at the VLMs. The workload from GL to the VLMs is shifted by transferring fast moving parts from GL to the VLMs. The picking efficiency of the VLMs is improved by balancing the workload of all five VLM pods, and by employing a more efficient 'pick-and-consolidate' picking strategy. The workload at GL is decreased by 25% and the workload at VLMs is increased by 13%. Despite the increase in workload at VLMs, 23% time savings could be achieved by balancing the utilization of all five VLM pods. Additional time savings of 20 minutes per order (8%) could be achieved by using 'pick-and-consolidate' picking strategy over 'pick-and-pass' picking strategy. / by Paramveer Singh Toor. / M. Eng. in Manufacturing
1176

Input/output linearization of uncertain systems with time delay control

Wu, Shang-Teh January 1993 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1993. / Includes bibliographical references (leaves 160-164). / by Shang-Teh Wu. / Ph.D.
1177

Aging of polyurethane foams

Ostrogorsky, Aleksandar G January 1986 (has links)
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1986. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Bibliography: leaves 151-153. / by Aleksandar G. Ostrogorsky. / Sc.D.
1178

HandWave : design and manufacture of a wearable wireless skin conductance sensor and housing / Wearable wireless skin conductance sensor and housing

Strauss, Marc D January 2005 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005. / Includes bibliographical references (p. 48-49). / This thesis report details the design and manufacture of HandWave, a wearable wireless Bluetooth skin conductance sensor, and dedicated housing. The HandWave collects Electrodermal Activity (EDA) data by measuring skin conductance over a pair of electrodes. The EDA data signal is used to infer the excitement level of the subject. The injection-molded housing is affixed to the wrist of the subject, and the electrodes are positioned on the fingers and/or palm. The HandWave amplification board utilizes a PIC to sample the EDA signal level with an analog-to-digital converter (ADC), control the gain of the amplification circuitry, and pass the data to a Bluetooth module. The Bluetooth module manages the wireless connection to a remote base-station and streams the EDA data over this link. Driver software on the base-station recomposes the EDA signal into standard units of conductance for display or further analysis. / by Marc D. Strauss. / S.B.
1179

2007 Formula SAE pedal box / Two thousand and seven Formula SAE pedal box

Schiller, Brad W January 2007 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007. / The purpose of this thesis is the design and implementation of the pedal box for the 2007 MIT Formula SAE car. Formula SAE is a collegiate competition in which groups of degree seeking students design and manufacture small formula style race cars to compete on design, cost, marketing, and performance. The pedal box is an integral part of the vehicle as the driver directly interacts with it making ergonomic considerations integral to the success of the design. The 2007 pedal box design emphasizes design for manufacture, adjustability, ergonomics and weight savings. An innovative design decreases the amount of space needed for the pedal box through the use of vertically mounted master cylinders while allowing for the d.river to adjust front to rear brake bias, brake pedal ratio, and location in the car. The design also causes a significant reduction in complexity and weight through a decrease in the number of components needed for manufacture. / by Brad W. Schiller. / S.B.
1180

Design, development, and validation of a remotely reconfigurable vehicle telemetry system for consumer and government applications

Siegel, Joshua Eric January 2011 (has links)
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011. / 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. 67-68). / This thesis explores the design and development of a cost-effective, easy-to-use system for remotely monitoring vehicle performance and drivers' habits, with the aim of collecting data for vehicle characterization and traffic shaping. Vehicular congestion and concerns over fuel reserves, pollution, and carbon emissions have recently emerged as prominent sociopolitical concerns. These problems are formidable, but could be addressed more fruitfully with better information about vehicles and drivers habits, leading to policies such as vehicle-specific congestion charging or an odometer-based road tax. Despite the proliferation of sensors in cars, data is often hidden due to the antiquated nature of the federally-required On-Board Diagnostics (OBD). Systems to log and process such data exist, but no well known reconfigurable systems augment OBD with additional sensor data and transmit it over a cellular network. This thesis proposes a system wherein vehicles become distributed sensors, each transmitting a rich supply of information. The standardization of OBD and decreasing cost of bandwidth make now an opportune time to develop a real-time logging system. Inexpensive processors make it possible to provide privacy through onboard calculation, obfuscating much personally-identifiable data. This document discusses the planning process, experimental configurations of hardware and software, results, and conclusions associated with the development of a cellular diagnostic system capable of supporting an "app" model for information feedback. I present a Bluetooth-OBD logger, a cellular logger, and a web interface capable of representing live and historical data from vehicles, including example applications for calculating congestion pricing. This project proves the feasibility of capturing data using a remotely reconfigurable controller area network (CAN) to general packet radio service (GPRS) interpreter, visualizing the information in real-time, and writing applications to make use of the incoming data. The hardware and software were proven successful in meeting the goals set for the project. The hardware proved robust, gathering data without issue for hundreds of miles. The sample data demonstrated low bandwidth use, identified network weaknesses, and pointed out issues with the currently-legislated OBD standard. This thesis closes by exploring future possibilities suggested by the development of this system, including wireless odometry and next-generation OBD. / by Joshua Eric Siegel. / S.B.

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