Touchless Charge Control of Neighboring Spacecraft in Geostationary and Cislunar Space
Abstract
This research project studies the open- and closed-loop charge control of a neighboring space object in the geosynchronous and cislunar orbit regimes. Spacecraft can naturally charge to multiple kilovolt levels in these regions depending on the local space weather conditions. If the spacecraft are flying in close proximity, only multiple craft radii apart, this can cause significant disturbance forces and torques as shown in prior research. Controlling this charging will facilitate docking operations by being able to equalize the relative potentials and avoid large arcing events that could damage spacecraft components and electronics. Further, the use of electrostatic forces has been studied for controlling close-proximity (dozens of meters) relative orbits and relative attitudes. This is beneficial for novel rendezvous and docking concepts, as well as creating an electrostatic tractor (ET) to either pull tumbling space debris to a disposal orbit, or modulate the ET to detumble the space object prior to docking. Prior work looked at active spacecraft charging with electron emission using basic single-Maxwellian plasma conditions assuming the space objects are isolated spheres. This research will consider complex multi-Maxwellian plasma conditions where multiple charge equilibriums can occur, consider the space weather conditions from geosynchronous to cislunar regions, consider non-spherical shapes, and in particular include method to touchless sense the target objects potential for novel closed-loop charging solutions. The cislunar region in particular is a complex space weather environment where both the Moon and the spacecraft can cast plasma wakes that do not occur in GEO orbit regimes. Thrust 1 will focus on touchless charge sensing that does not impact the overall target potential using pulsed electron beam strategies. This foundational work will support the closed-loop charge control. Thrust 2 develops charging models for the complex cislunar regions with wake considerations. These models are used to investigate open-loop charge equalizing strategies. Finally, thrust 3 combines the sensing and complex charge modeling capabilities to research closed-loop charging strategies to control both non-zero and near-zero potentials. The work is performed using laboratory experiments in conjunction with numerical and analytical modeling and analysis.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2024
- Source ID
- FA95502310570
Entities
People
- Hanspeter Schaub
Organizations
- Air Force Office of Scientific Research
- Regents of the University of Colorado
- United States Air Force