E/M launcher vibration and acceleration data analysis

Abstract

The main premise originally assumed as the cause for noise was the vibration caused by the barrel and projectile. This vibration was studied and removed. It is apparent that multiple sinusoidal vibrations are present. In a given object, a vibrational mode is induced with a frequency that depends on the object's physical dimensions and on the velocity of the propagating wave through the material or medium of that object. However, the rails could be considered as being positioned on a uniform and soft base which supports the rails from breech to muzzle. Any barrel fiber frequency mode would not be apparent in the accelerometer trace, nor would the rail effects. The projectile provides a filtering medium which would favor only the modes that it could uphold. The projectile has the greatest influence on this data, as was apparent in the frequency analysis. It is sufficient to run a low-pass filter on the data up to the fundamental mode of the projectile. >