Electromagnetic Damping and Vibration Isolation of Space Structures

摘要

Structures used in the vacuum, zero gravity environment of space are quite different form earth-bound system. Vibrations induced in a space structure by the operation of equipment internal to the structure should, to the greatest extent possible, be dissipated through heat generation so that this vibrational energy is not simply redistributed throughout the structure. The usual restricted fluid flow dashpot damping system has several serious drawbacks when operating within a space environment. Phase I proposed the quantitative assessment of electromagnetic damping that results when conducting but non-magnetic body moves through a region of localized magnetic field. It was shown theoretically in the Phase I proposal that this damping should depend quadratically upon both the velocity and the magnetic field seen by the moving conducting body. From this, it follows that electromagnetic damping (ED) has the potential for both large energy and power dissipation. Although our initial approximate theoretical estimate predicted strong damping under ideal circumstances, the appropriate partial differential equations (PDE) had not been solved at the onset of Phase I. Consequently, one could not calculate the damping magnitude that might be realized under practical conditions.