Electromagnetic Regolith Excavator

Abstract

Decades of research and development have been invested in various forms of railguns, coilguns and mass drivers. See http://settlement.arc.nasa.gov/75SummerStudy/Table_of Contents1.html Research at the Space Studies Institute in the 1980s refined the mass driver concept. See http://ssi.org/introduction-to-research/research-report/# mass-driver-iii The innovation of the Electromagnetic Regolith Excavator is to eliminate the use of a bucket or other container that is accelerated by the magnetic fields. Instead, magnetic particles in the regolith itself (nickel-iron grains and/or magnetite) are put into motion and they carry along with them a to-be-determined fraction (perhaps all) of the co-resident non-magnetic regolith particles. The Electromagnetic Regolith Excavator applies only attractive forces: no anchoring is required. This enables robotic and crewed spacecraft to safely collect surface material from asteroid targets that may be tumbling. Because no hard connection is required, no strong hazardous forces can be imparted to the collection apparatus aboard the spacecraft.

1 . A system of gathering and directing asteroid or planetary regolith containing sufficient ferromagnetic content via traveling waves of magnetism applied via a series of electromagnetic coils. 
     
     
         2 . A method of ( 1 ) where the material is gathered into a tube (or series of tubes), at least one of which has magnetic coils, so that the entrained material may be directed as desired. 
     
     
         3 . A method of ( 2 ) where the tube(s) are articulated such that they may be moved vertically and horizontally about the surface to increase the volume of regolith that may be gathered. 
     
     
         4 . A method of ( 2 ) where the tube(s) are flexible and the opening may be moved independently about the surface. 
     
     
         5 . A method of ( 1 ) where the magnetic content of the regolith is primarily nickel-iron grains and/or magnetite. 
     
     
         6 . A method of ( 1 ) where the regolith moves along the outside of the magnetic coils, rod, or tube, constrained only by momentum and/or magnetism. 
     
     
         7 . A regolith drill, wherein a tube (as in  2 ) or a rod (as in  6 ) is moved vertically to excavate the material from a single column of regolith. 
     
     
         8 . A regolith anchor, wherein a regolith drill (as in  7 ) is operated to set the tube or rod at depth, and then the magnetic fields are simultaneously activated to provide fraction and effectively hold an increased mass of material against the anchor. 
     
     
         9 . A method of ( 8 ) where electromagnetic coils are used to drill into the regolith and then permanent magnets (or permanently magnetizable coils) are used to maintain the anchor after power is removed.