Reversible helical electromagnetic launchers for time acceleration waveform replication

A 750 mm barrel length × 40 mm bore diameter hollow projectile, reversible helical electromagnetic launcher (RHEML) is evaluated for its ability to produce a negative acceleration (i.e., a “jerk”). The RHEML projectile and payload weighs approximately 750 grams and will travel with velocity up to 100 m/s. A 450 kJ multiple-module capacitive pulse forming network (PFN) with the ability to provide both positive and negative voltage and current is used to power the RHEML launcher. Special precautions must be taken when designing this type of PFN and RHEML. Theoretical and practical design guidelines for this type of PFN are presented and discussed. The results of the systematic experimental approach taken to generate and evaluate the transient current waveforms is presented and analyzed. Results show the reversible HEML is able to produce a negative jerk and travel in the opposite direction.