Decoupling Control of a Multiaxis Hydraulic Servo Shaking Table Based on Dynamic Model

Abstract

Hydraulic servo shaking table is an essential testing facility to simulate the actual vibration situation in real time. As a parallel mechanism, multiaxis hydraulic servo shaking table shows strong coupling characteristic among different degrees of freedom. When the multiaxis hydraulic shaking table moves to one direction, some unnecessary related motions will appear in other directions, which seriously affect the control performance. An effective approach to decouple motions in command direction and in unnecessary related directions is an urgent need for a higher precision control performance. In this work, the coupling phenomena and reasons of the multiaxis hydraulic servo table are analyzed based on dynamic model of a multiaxis hydraulic servo shaking table. In this regard, multiaxis hydraulic servo shaking table with strong coupling within the physical space is transformed into a set of single-input single-output systems that are independent of each other in the modal space. A decoupling control strategy is proposed in modal space to restrain the coupling motions. Simulation and experimental results show that the proposed control strategy can effectively improve the control performance and the decoupling effect.

Experiment Research on Complex Optimization Algorithm-Based Adaptive Iterative Learning Control for Electro-Hydraulic Shaking Tables

“…Guo [11] adopts the latest advances in deep learning to develop a physics-guided long short-term memory network for system identification of the shaking table. Huang [12] analyzed the coupling phenomena and reasons for the multiaxis hydraulic servo table based on a dynamic model of a multiaxis hydraulic servo shaking table. Li [13] analyzed the effects of the characteristics of the dual shaking tables-specimen interaction on the system performance.…”

“…Yang [11] proposed a combined controller with ultra-local model principle-based adaptive SMC to improve the sweptsine control precision of an electro-hydraulic shaking table considering the nonlinearities, uncertainties and unexpected disturbance. In [12], an adaptive dynamic surface control method with nonlinear disturbance observers was proposed to improve the tracking precision of an electro-hydraulic shaking table with unknown time-varying disturbances. To obtain a good acceleration replication effect for a hydraulic shaking table, a feed-forward inverse model controller based on the RELS algorithm was proposed by Shen [13].…”