Modeling and vibration decoupling control of multi-axial shaking table

Abstract

Traditional control strategy study of the multi-axial electro-hydraulic shaking table(MAEHST) is based on linear model, ignoring the coupling and nonlinearity factors, which results in the waveform distortion and the control precision. To overcome these limitations, a model considering the hydraulic system nonlinearity and mechanical coupling using the software Simulink/SimMechanics is built. A vibration decoupling control strategy based on multiple input multiple output (MIMO) system identification is proposed to improve the waveform replication precision. The proposed control method applies the MIMO H 1 estimator to identify frequency response function matrix (FRFM) of the system, not only considering the diagonal element, but the off-diagonal element to acquire the coupling characteristics of six degrees of freedom (DOFs) of MAEHST. And then the inverse frequency response function matrix (IFRFM) is calculated using the singular value decomposition technique to obtain the drive signal combined with the reference signal. Simulation experiments are carried out, and the results indicate that the MIMO vibration decoupling control strategy successfully minimizes the coupling and improve the waveform replication precision of the shaking table.

Kinematic analysis and bearing capacity optimization of fully decoupled two-rotation mechanisms

“…Many scholars and vehicle companies have carried out studies on vehicle durability test benches. The British Salvo company developed four-channel and sixchannel road simulation systems which are mainly used to test the bodies and chassis of vehicles (Zhang et al, 2015). Instron developed a road simulation test system for light or heavy vehicles (Mohajer et al, 2015) that was used for vehicle fatigue durability tests, comfort tests, NVH (noise, vibration, and harshness), and other common vehicle tests.…”