This calculator is for the theoretical shock response to a base input.  It has pre-coded options for
1/2 sine, triangular, rectangular and saw-tooth pulses where peak amplitude in g's and time pulse
in seconds are input.  It also has an option for a user input spectrum with up to 20 time points. The
suspended system includes the suspended weight on a linear spring (k) and viscous damper (c).  
A gravitational constant is also needed.  Any consistent set of units with seconds and cycles per
second (Hz)are required.

Output includes a chart of the input shock and shock response versus time. The un-damped natural
frequency, critical damping ratio and peak response-to-peak input are also output.

Some baseline cases where the analytical solution is known.

1) if a rectangular shock pulse is applied to an undamped system with a natural period of 2 times
the pulse time the response is 2 times the input shock level.
2) if a 1/2 sine shock pulse is applied to an un-damped system with a natural period of
approximately 1.7 times the pulse time the response is approximately 1.7 times the input level.