Studies to Increase Barrel Exit Velocity for Four-Stage Coil-Gun

Abstract

The operating principle for electromagnetic launchers (EMLs) is based on electromagnetic theory. The process in EMLs involves the creation of a varying or moving strong electromagnetic field, and ensuring movement of the projectile planned for launch with this electromagnetic field. Conceptually, there is no limit to the movement velocity of an electromagnetic field so there is no velocity limit for the object to be launched. In classic gun and satellite launch systems, the barrel exit velocity of the projectile can only be set during the production process. One of the features that make EMLs interesting is that they are very open to development. In line with this, this article designed a “new electromagnetic coil-gun” providing velocity to a ferromagnetic projectile without any mechanical force with an instantaneously changing field created by four ranked stator coils. For velocity of the projectile, data from optical systems inserted at the beginning of the stator coils were read and processed with an FPGA project developed for trigger controls. This project designed on the LabVIEW FPGA module was run on a NI MyRIO-1900 with a Xilinx FPGA board. The developed coil-gun had the coil locations and coil trigger points changed to increase barrel exit velocity and thus optimize the system. This article was completed using an FPGA project run with parallel processing and differs from other studies in the literature in that all pieces affecting the barrel exit velocity of the coil-gun were movable. In the study, data obtained at the end of each launch procedure were recorded on a flash disk inserted in the MyRIO and observed in real-time on a monitor. Variables like the voltage values applied to the coils, coil length, trigger points, and distances between coils were researched for effects on the maximum barrel velocity that can be obtained from the launcher and discussed in detail in this article.