Electromagnetic launchers

Abstract

Recent advances in energy storage, switching and magnet technology make electromagnetic acceleration a viable alternative to chemical propulsion for certain tasks, and a means to perform other tasks not previously feasible. Applications include the acceleration of gram-size particles for hypervelocity research and the initiation of fusion by impact, a replacement for chemically propelled artillery, the transportation of cargo and personnel over inaccessible terrain (front line support, ship-to-shore, emergency evacuation, forest fire control, etc.), and the launching of space vehicles to supply massive space operations (construction of solar power satellites, lunar and asteroid mining operations, manufacturing and research facilities), and for the disposal of nuclear waste. The simplest launcher of interest is the railgun, in which a short-circuit slide or an arc is driven along two rails by direct current. The most sophisticated studied thus far is the mass driver, in which a superconducting shuttle bucket is accelerated by a line of pulse coils energized by capacitors at energy conversion efficiencies better than 90 percent. Other accelerators of interest include helical, brush-commutated motors, discrete coil arc commutated drivers, flux compression momentum transformers, and various hybrid electro-chemical devices. A facility to investigate the most promising accelerating mechanisms has been established at this laboratory.