The Terminator Tape Low-Cost Deorbiting System

Period of Performance: 02/17/2009 - 02/17/2010

$100K

Phase 1 SBIR

Recipient Firm

Tethers Unlimited, Inc.
11711 N. Creek Pkwy S., Suite D113 Array
Bothell, WA 98011
Principal Investigator

Abstract

TUI proposes to develop a Terminator Tape deorbit module that will utilize both aerodynamic drag enhancement and passive electrodynamic drag to enable spacecraft to comply with post-mission orbital lifetime restrictions while minimizing cost, mass, volume, and footprint impacts to the spacecraft. At the completion of the satellites mission, this module will deploy a several-hundred meter length of metalized mylar tape, utilizing gravity gradient forces to align it along the local vertical so as to maximize its aerodynamic drag area. Voltages induced by the conducting tapes motion through the Earths magnetic field will charge the top and bottom of the tape relative to the ambient environment, driving collection of electron and ion currents which will result in a small but significant flow of current along the length of the tape. This current will induce an electrodynamic drag force on the system, enhancing the orbital decay of the system, especially at mid-to-high-LEO altitudes where neutral drag is small. The proposed effort will develop a preliminary design and prototype for the hardware and its spacecraft interface, perform detailed analysis and simulation of the deorbit performance of the system, and develop a plan for maturation and validation of the hardware through ground and on-orbit testing. BENEFIT: The Terminator Tape deorbit module will provide a lightweight, low-cost, autonomous capability for ensuring that spacecraft and upper stages meet orbital lifetime requirements. It will enable DoD spacecraft lacking propulsion capabilities to operate at mid-to-high-LEO altitudes without violating debris mitigation requirements, and it will enable spacecraft with propulsion to be operated to their full delta-V and lifetime capability, maximizing return on the investment made in these systems. Additionally, it can provide a back-up means for stabilizing spacecraft that experience attitude control failures. The Terminator Tape will be equally applicable to DoD, NASA, and commercial spacecraft, and its potential market is every satellite, upper stage, interstage, and other object launched into LEO.