Active vibration reduction by optimally placed sensors and actuators with application to stiffened plates by beams

2014 ◽  
Vol 23 (11) ◽  
pp. 115018 ◽  
Author(s):  
A H Daraji ◽  
J M Hale
Keyword(s):  
Vibration Reduction ◽  
Stiffened Plates ◽  
Sensors And Actuators ◽  
Active Vibration

Optimal Placement of Piezoelectric Sensors and Actuators for Controlled Flexible Linkage Mechanisms

2005 ◽  
Vol 128 (2) ◽  
pp. 256-260 ◽  
Author(s):  
Xianmin Zhang ◽  
Arthur G. Erdman
Keyword(s):  
Vibration Control ◽  
Simulation Analysis ◽  
Active Vibration Control ◽  
Optimal Placement ◽  
Control Effect ◽  
Sensors And Actuators ◽  
Piezoelectric Sensors And Actuators ◽  
Active Vibration ◽  
Flexible Mechanism ◽  
Flexible Linkage

The optimal placement of sensors and actuators in active vibration control of flexible linkage mechanisms is studied. First, the vibration control model of the flexible mechanism is introduced. Second, based on the concept of the controllability and the observability of the controlled subsystem and the residual subsystem, the optimal model is developed aiming at the maximization of the controllability and the observability of the controlled modes and minimization of those of the residual modes. Finally, a numerical example is presented, which shows that the proposed method is feasible. Simulation analysis shows that to achieve the same control effect, the control system is easier to realize if the sensors and actuators are located in the optimal positions.

scholarly journals Optimal switch timing for piezoelectric-based semi-active vibration reduction techniques

2017 ◽  
Vol 28 (16) ◽  
pp. 2275-2285 ◽  
Author(s):  
Christopher R Kelley ◽  
Jeffrey L Kauffman
Keyword(s):  
Vibration Reduction ◽  
Harmonic Excitation ◽  
Peak Displacement ◽  
Reduction Techniques ◽  
At Resonance ◽  
Near Resonance ◽  
Switch Time ◽  
Vibration Sensing ◽  
Dimensional Parameters ◽  
Active Vibration

Piezoelectric-based semi-active vibration reduction techniques typically rely on rapid changes in the electrical boundary conditions or corresponding stiffness state. Approaches such as state switching and synchronized switch damping on a resistor or an inductor require four switching events per vibration cycle, with switch timing associated with displacement extrema. Any deviation from this switch timing affects the performance of these techniques. Typical harmonic forcing analyses focus on the energy dissipation and only evaluate the performance at resonance. This study evaluates displacement reduction for harmonic excitation, both at resonance and for frequencies near resonance. Furthermore, it examines the effect of sub-optimal switch timings. Numerical simulations of a non-dimensional model are performed, and an analytical solution is derived for any switch time. This analysis shows that the optimal switch timing depends on the forcing frequency relative to the natural frequency of the structure. Thus, the classical switch time at peak displacement is only optimal when the excitation is exactly at resonance. Even when the optimal switch timing is known, uncertainties in vibration sensing cannot guarantee that switches will occur at the desired moment. Therefore, this work characterizes the degradation in vibration reduction performance when switching away from the optimal switch time based on global, non-dimensional parameters.

Self-powered active control of elastic and aeroelastic oscillations using piezoelectric material

2017 ◽  
Vol 28 (15) ◽  
pp. 2023-2035 ◽  
Author(s):  
Tarcísio Marinelli Pereira Silva ◽  
Carlos De Marqui
Keyword(s):  
Finite Element ◽  
Energy Harvesting ◽  
Vibration Control ◽  
The Self ◽  
Base Excitation ◽  
Sensors And Actuators ◽  
Multilayered Structures ◽  
Numerical Predictions ◽  
Active Vibration ◽  
Self Powered

Piezoelectric materials have been used as sensors and actuators in vibration control problems. Recently, the use of piezoelectric transduction in vibration-based energy harvesting has received great attention. In this article, the self-powered active vibration control of multilayered structures that contain both power generation and actuation capabilities with one piezoceramic layer for scavenging energy and sensing, another one for actuation, and a central substructure is investigated. The piezoaeroelastic finite element modeling is presented as a combination of an electromechanically coupled finite element model and an unsteady aerodynamic model. An electrical circuit that calculates the control signal based on the electrical output of the sensing piezoelectric layer and simultaneously energy harvesting capabilities is presented. The actuation energy is fully supplied by the harvested energy, which also powers active elements of the circuit. First, the numerical predictions for the self-powered active vibration attenuation of an electromechanically coupled beam under harmonic base excitation are experimentally verified. Then, the performance of the self-powered active controller is compared to the performance of a conventional active controller in another base excitation problem. Later, the self-powered active system is employed to damp flutter oscillations of a plate-like wing.

Effect of Switch Delays on Piezoelectric-Based Semi-Active Vibration Reduction Techniques

2015 ◽  
Author(s):  
Christopher R. Kelley ◽  
Jeffrey L. Kauffman
Keyword(s):  
Vibration Reduction ◽  
Local Strain ◽  
Electrical Energy ◽  
Peak Strain ◽  
Reduction Techniques ◽  
State Switching ◽  
Switch Time ◽  
Active Vibration ◽  
And Performance ◽  
The Ideal

Piezoelectric transducers have been used for semi-active vibration reduction in structures by altering the stiffness state and dissipating electrical energy. Common approaches include state switching, synchronized switch damping on a resistor (SSDS), and synchronized switch damping on an inductor (SSDI). Each of these methods requires four switches per vibration cycle, so any delay in the switch from the ideal moment could have a significant effect on the vibration reduction. An experimental investigation into the effect of switch delays on these techniques reveals that the abrupt change in piezoelectric voltage from the switch has the effect of a step input on the structure, which may excite higher order modes and increase the peak strain. This non-ideal switching of boundary conditions has implications towards the design and performance of these state switching techniques. Switching at the peak is classically considered the ideal switch time, but the influence of the switch on the local strain may actually result in a higher peak strain for the structure than with a delayed switch. This paper will examine switch times that lead and lag the ideal case for state switching, SSDS, and SSDI to quantify the level of vibration reduction achieved under non-ideal peak sensing.

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