Date of Award

Spring 1-1-2013

Document Type

Thesis

Degree Name

Master of Science in Aerospace Engineering (MSAeroE)

Department

Aerospace Engineering Sciences

First Advisor

Scott Palo

Second Advisor

Eliot F. Young

Third Advisor

Zoltan Sternovsky

Abstract

High altitude balloons are emerging as low-cost alternatives to orbital satellites in the field of telescopic observation. The near-space environment of balloons allows optics to perform near their diffraction limit. In practice, this implies that a telescope similar to the Hubble Space Telescope could be fl own for a cost of tens of millions as opposed to billions.

While highly feasible, the design of a balloon telescope to rival Hubble is limited by funding. Until a prototype is proven and more support for balloon science is gained, projects remain limited in both hardware costs and man hours. Thus, to effectively create and support balloon payloads, engineering designs must be effcient, modular, and if possible reusable. This thesis focuses specifically on a modular power system design for the BRRISON comet-observing balloon telescope. Time- and cost-saving techniques are developed that can be used for future missions.

In this thesis, a modular design process is achieved through the development of individual circuit elements that span a wide range of capabilities. Circuits for power conversion, switching and sensing are designed to be combined in any configuration. These include DC-DC regulators, MOSFET drivers for switching, isolated switches, current sensors and voltage sensing ADCs. Emphasis is also placed on commercially available hardware. Pre-fabricated DC-DC converters and an Arduino microcontroller simplify the design process and offer proven, cost-effective performance.

The design of the BRRISON power system is developed from these low-level circuits. A board for main power distribution supports the majority of flight electronics, and is extensible to additional hardware in future applications. An ATX computer power supply is developed, allowing the use of a commercial ATX motherboard as the fl ight computer. The addition of new capabilities is explored in the form of a heater control board. Finally, the power system as a whole is described, and its overall performance analyzed. The success of the BRRISON power system during testing and fl ight proves its utility, both for BRRISON and for future balloon telescopes.