Rishi Verma wrote:The tiny para above have too many factually incorrect statements, terminology etc. If discussing engineering it's important to use the right terminology and not throw in terms like "2nd harmonic" besides I think you are mistaking resonance with vibrations.
OK, kindly list at least some out of the 'too many', for knowledge sake. Also, if you know how the gun vibration looks like, please share it, since it would come useful.
ok, i will make a zimble list of what happens and one can find the incorrect premises in the para
0) hand held gun recoil is not the same as vibrations caused by gatling type of rapid fire gun, depending on how the gun is mounted, the barrel vibrations get transmitted to the support structure (here the LCA) http://www.varmintal.com/atune.htm
(in above link a single shot results in vibrations of the barrel at about 80Hz, the freq depends on the length of the barrel, speed of the bullet, etc and is well understood with many software models available for simulations)
even a single shot from any gun can cause vibrations
1) you estimated 60Hz basic freq. based on firing rate of 3600 rounds per min, lets assume its the dominant "natural frequency", typical gatling type of guns have a wide range from 2000 rounds per min to 6000 rounds per min
2) "2nd harmonic" is not caused by gun itself but is caused by gun + support (the whole system) and if 2nd harmonic is dominant then even harmonics are present so the "natural frequency " 60Hz is not present which is 1f
2f, 4f, 6f... Etc
If odd harnonics are caused by the system then
1f, 3f, 5f etc
(imagine a pendulum in free swing.. The natural frequency is 1 divided by the period of oscillation, but if someone taps the swinging pendulum at some frequency then harmonics will arise)
3) these frequency domain harmonics are not the be confused with fourier series approximations of signals where all harmonics extending to infinity are present to define any wave shape
4) if the pendulum (or gatling gun) are in resonance (pendulum being tapped with a hammer at same frequency or a frequency of any harmonic (odd or even) then the pendulum motion will reach "instability", and may cause destructive behaviour.