ILC based active vibration control of smart structures

Abstract

Vibration control of flexible structures is observed to be a good way to maintain structural integrity as well as to optimize performance for space structures currently. Taking the piezoelectric flexible structure as research object, this paper focuses on the methodology and implementation of a vibration suppression system. An efficient method to simulate and analyze the piezoelectric plate is presented with ANSYS applied, while an iterative learning control (ILC) algorithm is proposed as the control strategy. A finite element model of the flexible plate is constructed by an APDL (ANSYS Parameter Design Language) program. By transient analysis of piezoelectric flexible plate, the models of the control channel and the primary path are obtained. Finally, an ILC based controller, having good cancellation of the vibration of the flexible plate, is developed. The ANSYS experiments suggest that analyzing the piezoelectric flexible plate by ANSYS is a cost-effective method. The SIMULINK results show that the open-loop PID-type learning algorithm is effective for the active vibration control. Keywords-piezoelectric smart structures; active vibration control; iterative learning control; ANSYS; MATLAB;. As space structures, having large mechanical flexibilities, often are required to have stringent vibration suppression and pointing accuracies, vibration control of flexible structures such as large spacecraft or satellite, being observed to be a good way to maintain structural integrity as well as to optimize performance, currently is an active field of research[1].While unavoidable model uncertainties of the smart structures are generally difficult to manage with conventional control algorithms that should be designed based upon the mathematical model of the controlled plant, interactive learning control, a specialized feedforward control strategy for improving control accuracy by learning about the system from repeated trials, has found its application in this area as periodically disturbing and periodically driving generally involved in [2].Both ANSYS experiment and MATLAB simulations were performed to verify the effectiveness of the method and the control system. Based on an APDL program, system identification was done by MATLAB system identification toolbox. With the control channel and primary path model of the vibration control system obtained, an open-loop PID-type learning controller was designed and simulations by SIMULINK were done with a good performance achieved.

Research status and prospect of pulsating active control of hydraulic pipeline

“…The self-seeking optimal algorithm [18] is a control method that automatically searches for and keeps the output of the controlled system in the extreme state, without establishing a mathematical model of the controlled object, and constantly searching to find out the extreme point of the input-output characteristic of the controlled object representing the optimal operating state [17] . Figure 7 below is the structure diagram of the self-optimal algorithm, the collected pressure pulsation data is changed FFT to obtain the pulsation spectrum, and the amplitude A and phase ω parameters of the output signal…”