Why do I need a control system for my shaker?
The control system is the portion of the overall system whose function is to maintain the prescribed input into the test article under test.
It is the computer control system that receives input signals from the transducers mounted on the test article and provides the output signal to drive the shaker system.
Accurate control requires compensation for the dynamic characteristics of the shaker, fixture and test article. It is further complicated by non-linear behavior due to hydraulic actuators or varying structural dynamics as the excitation level changes.
If the test was a swept sine test as shown below :
and the non-linear response of the product fixture were
The controller’s output would have to be as below to reproduce the required test.