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Description of Driving Event:

The Gateway Tether Experiment (GATE) is a single tether satellite system that will develop and test control technology for a tethered system. Originally a free flying tethered system released from a gateway special canister on the orbiter, the system is now one experiment in the Tether Dynamics Explorer (TDE) series launched by a Delta II. The system consists of a Delta II second stage and subsatellite connected by a single tether. The subsatellite contains a motorized reel mechanism that will be the primary means of control actuation. A prototype reel mechanism has been constructed for use in the GATE system and ground tested. The reel mechanism consists of a spool and a level wind mechanism that are driven by independent stepping motors. The spool is designed to hold 1.8 km of 0.075 cm diameter tether.

A paper, "Ground-based Implementation and Verification of Control Laws for Tethered Satellites", by David A. Gwaltney (NASA Langley Research Center) and Michael E. Greene (Auburn University) was published in the Journal of Guidance, Control, and Dynamics in the edition of January-February, 1992 (pages 271-273). The paper contains system equations and discusses testing and testing results.