HIGH ALTITUDE BALLOON (HAB)SENIOR DESIGN PROJECT OderaEziolisa Dale Hardacre Kaneisha Wilson Advisors: Joseph C. Slater, PhD, PE J. Mitch Wolff, PhD Bruce Rahn Graduate Student Mentors: Emily Henry Nicholas Baine
Outline • Project Importance • Project Scope • Design and Experimental Process • Expected Results • What issues/Problems we are facing • Budget
Project Importance • During natural disasters, amateur radio is often the first form of communication. • Practical use of handheld radio equipment in VHF and above frequencies is limited to line of sight propagation. • The use of a repeater can greatly increase the communications range of an amateur radio operator.
Scope of Project • For the scope of this project, the team will focus on New Orleans, LA after Hurricane Katrina. • The diameter of the designated communication area was found to be 300 miles.
This Year’s Objective • Maintain communication with the balloon for 24 hours within the designated communication area
This Year’s Objective • Maintain communication with the balloon for 24 hours within the designated communication area • Deploy a repeater into near space • Stabilize altitude • Change altitudes if needed
Background Balloon • What is a High Altitude Balloon? • 60k-120k Feet • Typically filled with helium or hydrogen Parachute Reducing Ring Payload Box
Basic Schematic • Altitude Controlled through a Solar Balloon based on the concept of NASA’s Long-Life Stratospheric Balloon System
Expected Results • Based upon collected wind data, the balloon can stay within the necessary communications range without use of a propulsion system. • Using different altitudes the balloon will be able to find changing wind speeds and directions to control the balloon. • Practical winds speeds are available above 60,000 feet.
Maximum Allowable Speed • Favorable wind speeds can be observed during the months of February and March between 60,000 and 100,000 feet.
Drift Range • The diameter of the disaster area is 𝑑=300 miles • The radius 𝑟 is determined by the altitude, 𝑟=√(2∗ℎ,) where ℎ is the altitude in feet. • The drift is the allowable movement, in a straight line, of the communications circle while keeping the disaster circle within its limits 𝑑𝑟𝑖𝑓𝑡=2𝑟−300
Drift Range Repeater coverage versus disaster area with balloon at 100K feet.
Maximum Allowable Speed • These calculations assume the balloon travels at a constant speed in one direction.
Wind Data February 2012 • Altitudes between 70,000 and 90,000 feet have a significantly greater chance of success. • Only 4 out of 29 days (14%) had average wind speeds above the allowable maximum in all altitude ranges.
Other Challenges • Equipment must operate at extreme temperatures in vacuum. • Long duration testing is required due to length of flight • Create a mechanism to allow for emergency drop procedures if communication with balloon is lost. • Timed-drop mechanism that can be reset with handheld device
Other Challenges • Design package to keep all of the component temperature within their designed operating range. • To do this analysis we will have to know constants such like the heat transfer coefficient and the thermal conductivity of the material that makes up the wall of the control module.