Feed-forward inverse control for transient waveform replication on electro-hydraulic shaking table

Abstract

In this paper, an improved feed-forward inverse control scheme is proposed for transient waveform replication (TWR) on an electro-hydraulic shaking table (EHST). TWR is to determine whether a test article can remain operational and retain its structural integrity when subjected to a specific shock and vibration environment. Feed-forward inverse transfer function compensation is a useful technique to improve the tracking accuracy of the TWR on the EHST system due to their inherent hydraulic dynamics. Whenever a feed-forward inverse transfer function is employed, it is critical to design the identification accuracy of the inverse transfer function. A combined control strategy, which combines a feed-forward inverse transfer function compensation approach with a simple internal model control (IMC) and a real-time feedback controller, is proposed to minimize the effect of the system uncertainty and modeling error, and further to improve the tracking accuracy of the TWR. Thus, the proposed control strategy combines the merits of feed-forward inverse transfer function compensation and IMC. The procedure of the proposed control strategy is programmed in MATLAB/Simulink, and then is compiled to a real-time PC with Microsoft Visual Studio.NET for implementation. Simulation and experimental results demonstrated the viability of the proposed combined control strategy.

Attitude synchronous tracking control of double shaking tables based on hybrid fuzzy logic cross-coupled controller and adaptive inverse controller

“…Assume that the position close-loop system is described as an autoregressive moving average model [9].…”

“…Electro-hydraulic shaking table is the important test equipment for replicating actual vibration situations in civil and architectural engineering, earthquakeresistance test and many other applications [8,15,18,20]. Nowadays, there many large span structures such as bridges, dams, railways and pipelines etc.…”

“…Many researches demonstrate that feedforward compensator control is an effective method for improvement of shaking table's tracking accuracy [2,9]. The AIC algorithm was originally developed by Windrow and was used in the tracking control as an alternative to the conventional feedforward control [2].…”

“…The AIC algorithm was originally developed by Windrow and was used in the tracking control as an alternative to the conventional feedforward control [2]. Shen [9] has applied the algorithm into shaking table's tracking control to improve tracking precision.…”

Optimal Design and Hybrid Control for the Electro-Hydraulic Dual-Shaking Table System

“…It is because the control precision directly determines the reality of earthquake replication and in turn influences the feasibility of the performance research of the specimen, which is explained in [7,8]. However, due to the eccentricity of the load mass, cross-coupled characteristic, system nonlinearity and disturbance, the control system has a poor tracking and synchronization precision [9,10].…”