Comparison of heat sink and fan combinations and thermal electric coolers for use in the Mars Gravity Biosatellite

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references.An experiment was conducted to help compare possible cooling methods for the payload module of the Mars Gravity Biosatellite. The Satellite will be launched into space with 15 mice on board and rotated to create a 0.38g centrifugal acceleration, the acceleration due to gravity on Mars. The mission will last 5 weeks and take valuable data on mammal's responses to extended periods of time in reduced gravity. Because of a large heat shield needed for reentering the Earth's atmosphere, the payload module is nearly perfectly insulated. It is therefore necessary to actively transport heat out of the capsule and radiate it off into space. A thermal electric cooler and a heat sink and fan combination were compared in this experiment for that purpose, using a Styrofoam cooler as a model payload. It was found that the fan and heat sink combination was more efficient than the thermal electric cooler. The coefficient of performances of the respective cooling elements was found to be 5.89 for the fan and heat sink while only 1.67 for the thermal electric cooler. However, it was also observed that the thermal electric cooler, while less efficient, could transport much more heat than the fan and heat sink alone, 26.4 Watts compared to 9.73 Watts in the experimental set up. It has been recommended that a combination of a fan and heat sink be used in the payload module of the satellite.by Aaron J. Parness.S.B

Boulder Capture System Design Options for the Asteroid Robotic Redirect Mission Alternate Approach Trade Study

This paper presents a boulder acquisition and asteroid surface interaction electromechanical concept developed for the Asteroid Robotic Redirect Mission (ARRM) option to capture a free standing boulder on the surface of a 100 m or larger Near Earth Asteroid (NEA). It details the down select process and ranking of potential boulder capture methods, the evolution of a simple yet elegant articulating spaceframe, and ongoing risk reduction and concept refinement efforts. The capture system configuration leverages the spaceframe, heritage manipulators, and a new microspine technology to enable the ARRM boulder capture. While at the NEA it enables attenuation of terminal descent velocity, ascent to escape velocity, boulder collection and restraint. After departure from the NEA it enables, robotic inspection, sample caching, and crew Extra Vehicular Activities (EVA)

Stick shift

Thesis (S.B. in Creative Writing)--Massachusetts Institute of Technology, Dept. of Humanities, Program in Writing and Humanistic Studies, 2004.Stick Shift is a novel that has undergone several rounds of significant revision. Scott, the book's main character, is a sarcastic American who travels to England to move in with an ex-girlfriend. He experiences all of the obstacles involved in moving to a new country, leaving his home, and settling down with a woman in a comic sequence told in seven chapters.The introduction to this piece outlines my history as a writer, primarily focusing on my development at MIT. The thesis project is discussed and followed from its initial seed all the way through to its current state.by Aaron Parness.S.B.in Creative Writin