Poles and Zeros of system

[sgsawant]

I have a machine in my lab which is basically a spring-mass-damper system. I need to find the poles and zeros of the system. Is there a straight forward method for doing the same?

Basically I can given any number of inputs to the system (in the form of step force or impulse force) and can take equivalent outputs (using a displacement sensor). What I am intending to find is the transfer function.

Please help,

Regards,

-sgsawant