Dual-purpose Resonate Actuators for Electromagnetic Formation Flight and Wireless Power Transfer

Abstract

This paper describes the development and demonstration of a single set of hardware to perform both electromagnetic formation flight (EMFF) maneuvers and wireless power transfer (WPT). The hardware uses resonant coils to generate electromagnetic fields, which in one mode interact to provide for control of a spacecraft cluster without expending propellant, and in another mode couple to inductively transfer power. Developed under the project name RINGS, standing for Resonant Inductive Near-field Generation System, the hardware attaches to the formation flight test facility on-board the International Space Station, called SPHERES (Synchronized Position Hold, Engage, Reorient, Experimental Satellites). It is the first system to utilize dual-purpose hardware to achieve both EMFF and WPT, and this is the first time that such a capability has been demonstrated in a micro-gravity, six-degree of freedom environment. The RINGS system serves primarily as a testbed for EMFF control algorithm development, and operation onboard the ISS allows for more complicated and realistic algorithms to be tested compared to the restrictive dynamic environment of flat floor facilities on the ground, or the limited duration reduced gravity flights. Design and development of the support hardware and electronics, as well as test results from ground testing, a parabolic flight campaign, and the preliminary results from the International Space Station hardware checkout are presented.