Dual Loop Master Controller

The Xcite System Master Controller provides all dual loop functions needed for accurate closed loop control and display of the static and dynamic test variables, while producing the highest electro-hydraulic frequency response. At the heart of each Xcite System is the Master Controller, a compact electronic control package which provides all of the controls and displays necessary to operate a controlled force or torque exciter system. The Xcite Master Controller is unique in that it provides electro-hydraulic excitation over a broad frequency range, unprecedented by any previous electro-hydraulic excitation system. It achieves its great frequency range through the use of sophisticated circuitry, high voltage inputs to the servovalve and compression control of the dynamic feedback variable in addition to the conventional servo control of the static loop. Static parameters such as force or displacement may be matched with dynamic control variables such as force, displacement, velocity, acceleration or strain for maximum test flexibility.

The dual control loop design of the Xcite Master Controller affords three major advantages to the structural dynamist. First, the compression control of the dynamic loop changes the amplitude of the system drive signal dynamically to adjust the displacement output of the exciter to maintain a constant sine force even as the compliance of the structure changes during frequency sweeps.

This allows the study of non-linear structures by developing a family of data curves with varying levels of constant static and dynamic forces.

Second, the dual loop philosophy allows the mixture of feedback signals such as static displacement and dynamic force when testing compliant structures such as an automotive suspension or engine mounting subsystem. The static control may be force or displacement, while the dynamic control may be force, displacement, velocity or acceleration.

Third, a user selectable power amplifier input allows the dynamist to use either an external digital shaker control system or FFT analyzer DAC to drive the system with random, shaped random, white noise, chirp, pulse or user-generated waveforms. Master Controllers are rack-mountable and may be located hundreds of feet from the exciter head and power supply.