ONE-DIMENSIONAL TESTBED FOR COULOMB CONTROLLED SPACECRAFT

This paper discusses the preliminary results of a novel testbed developed to examine relative motion of craft using electrostatic or Coulomb forces. The Coulomb Formation Flight (CFF) concept uses active charge emission to control the naturally occurring spacecraft potential in space to maintain desired separation distances. These forces are on the order of milli-Newtons and can strongly influence relative motion of geostationary satellites dozens of meters apart. Simulating such charged relative motion in a terrestrial environment is very challenging. The testbed consists of a non-conducting one-dimensional hover track which can levitate a charged craft. With a secondary charged object and the ability to change the potential it is possible to actuate the suspended craft and study the relative motion due to charge. The challenges of developing this first generation electrostatic actuation testbed are outlined, including the mechanics of constructing the hover track, sensing the position of the cart, limiting the airflow supply as well as designing and implementing the cart which carries an electrostatic charge. Gravity disturbances are characterized and presented with test run data as well as preliminary results demonstrating that the Coulomb testbed successfully achieves electrostatic relative motion actuation.