High performances signal generator implemented on two axes hydraulic pulsator

In this paper is presented a specific realization of 2-axe hydraulic vibration exciter, i.e. hydraulic pulsator (vibrator), with the driving system based on hydraulic servo drive and high performances signal generator. This mechanical system presents a part of testing laboratory for vibration influence on a human body researching, with ride comfort point of view. Signal generator is based on Direct Digital Synthesis method (DDS), with possibility of choosing different excitation types (sine wave, triangular wave or stochastic signal) and frequency and amplitude fine tuning. Different signal generation, with frequency range (0.1-31.5) Hz and amplitude range (0-50) mm, is detailed presented. Experimental results of hydraulic platform displacement (oscilloscopic waveforms and spectrum in frequency domain) over both axes and real mass load for different excitation types from signal generator are presented too.