Development of a reversible helical electromagnetic launcher

The first-ever reversible helical electromagnetic launcher (HEML) to both accelerate and decelerate a projectile is presented and discussed. The reversible HEML is a hollow-projectile geometry with a barrel length of 750 mm and a bore diameter of 40 mm. Power for the reversible HEML is provided by a 3-module capacitive pulse forming network (PFN) that has a total energy storage of 1 MJ. Projectile mass is approximately 700 grams. The largest measured acceleration is 8000 m/s² immediately followed by a deceleration pulse of 15,000 m/s². Pulse lengths for the acceleration and deceleration pulses varied from 5 ms to a maximum of 14.5 ms. An uncertainty analysis and repeatability study was also done with regard to the measured results. Opportunities for improvement in this new proven technology are also explored.