A New X-Actuator Design for Controlling Wing Bending and Twisting Modes

1999 ◽  
Author(s):  
R. Ye ◽  
J. H. Ding ◽  
H. S. Tzou

Abstract Recent development of smart structures and structronic systems has demonstrated the technology in many engineering applications. Active structural control of aircraft wings or helicopter blades (e.g., shapes, flaps, leading and/or trailing edges) can significantly enhance the aerodynamic efficiency and flight maneuverability of high-performance airplanes and helicopters. This paper in to evaluate the dual bending and torsion vibration control effects of an X-actuator configuration reconfigured from a parallel configuration. Finite element (FE) formation of a new FE using the layerwise constant shear angle theory is reviewed and the derived governing equations are discussed. Bending and torsion control effects of plates are studied using the FE method and also demonstrated via laboratory experiments. FE and experimental results both suggest the X-actuator is effective to both bending and torsion control of plates.

Author(s):  
H. S. Tzou ◽  
Y. Bao ◽  
C. S. Chou

Abstract Adaptive shape control is essential in many high-performance engineering systems, such as nozzles, airplane wings, helicopter blades, etc. Recent development of smart structures and structronic systems offers new alternatives to shape control with inherent and embedded actuator components. Imposed shape control often involves large deformations implying that the conventional linear theory is no longer applicable. This study is to explore a new structural control concept based on nonlinear theories. Nonlinear piezoelectric shell equations are derived based on von Karman geometric nonlinearity. Physical significance and application are discussed. As to compare the linear and nonlinear theories, a zero-curvature shell–plate is investigated. Analytical results suggest that the linear theory is indeed invalid when large deformation shape control is considered. Differences between the two theories are presented. Control effects of the plate with polymeric and ceramic piezoelectric actuators are compared.


2020 ◽  
Vol 15 (3) ◽  
pp. 37-48
Author(s):  
Zubair Rashid Wani ◽  
Manzoor Ahmad Tantray

The present research work is a part of a project was a semi-active structural control technique using magneto-rheological damper has to be performed. Magneto-rheological dampers are an innovative class of semi-active devices that mesh well with the demands and constraints of seismic applications; this includes having very low power requirements and adaptability. A small stroke magneto-rheological damper was mathematically simulated and experimentally tested. The damper was subjected to periodic excitations of different amplitudes and frequencies at varying voltage. The damper was mathematically modeled using parametric Modified Bouc-Wen model of magneto-rheological damper in MATLAB/SIMULINK and the parameters of the model were set as per the prototype available. The variation of mechanical properties of magneto-rheological damper like damping coefficient and damping force with a change in amplitude, frequency and voltage were experimentally verified on INSTRON 8800 testing machine. It was observed that damping force produced by the damper depended on the frequency as well, in addition to the input voltage and amplitude of the excitation. While the damping coefficient (c) is independent of the frequency of excitation it varies with the amplitude of excitation and input voltage. The variation of the damping coefficient with amplitude and input voltage is linear and quadratic respectively. More ever the mathematical model simulated in MATLAB was in agreement with the experimental results obtained.


2003 ◽  
Vol 22 (2) ◽  
pp. 97-108 ◽  
Author(s):  
Yan Sheng ◽  
Chao Wang ◽  
Ying Pan ◽  
Xinhua Zhang

This paper presents a new active structural control design methodology comparing the conventional linear-quadratic-Gaussian synthesis with a loop-transfer-recovery (LQG/LTR) control approach for structures subjected to ground excitations. It results in an open-loop stable controller. Also the closed-loop stability can be guaranteed. More importantly, the value of the controller's gain required for a given degree of LTR is orders of magnitude less than what is required in the conventional LQG/LTR approach. Additionally, for the same value of gain, the proposed controller achieves a much better degree of recovery than the LQG/LTR-based controller. Once this controller is obtained, the problems of control force saturation are either eliminated or at least dampened, and the controller band-width is reduced and consequently the control signal to noise ratio at the input point of the dynamic system is increased. Finally, numerical examples illustrate the above advantages.


Actuators ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 62
Author(s):  
Ilia Uvarov ◽  
Pavel Shlepakov ◽  
Artem Melenev ◽  
Kechun Ma ◽  
Vitaly Svetovoy ◽  
...  

Microfluidic devices providing an accurate delivery of fluids at required rates are of considerable interest, especially for the biomedical field. The progress is limited by the lack of micropumps, which are compact, have high performance, and are compatible with standard microfabrication. This paper describes a micropump based on a new driving principle. The pump contains three membrane actuators operating peristaltically. The actuators are driven by nanobubbles of hydrogen and oxygen, which are generated in the chamber by a series of short voltage pulses of alternating polarity applied to the electrodes. This process guaranties the response time of the actuators to be much shorter than that of any other electrochemical device. The main part of the pump has a size of about 3 mm, which is an order of magnitude smaller in comparison with conventional micropumps. The pump is fabricated in glass and silicon wafers using standard cleanroom processes. The channels are formed in SU-8 photoresist and the membrane is made of SiNx. The channels are sealed by two processes of bonding between SU-8 and SiNx. Functionality of the channels and membranes is demonstrated. A defect of electrodes related to the lift-off fabrication procedure did not allow a demonstration of the pumping process although a flow rate of 1.5 µl/min and dosage accuracy of 0.25 nl are expected. The working characteristics of the pump make it attractive for the use in portable drug delivery systems, but the fabrication technology must be improved.


2016 ◽  
Vol 24 (6) ◽  
pp. 1051-1064 ◽  
Author(s):  
Mehdi Soleymani ◽  
Amir Hossein Abolmasoumi ◽  
Hasanali Bahrami ◽  
Arash Khalatbari-S ◽  
Elham Khoshbin ◽  
...  

Model uncertainties and actuator delays are two factors that degrade the performance of active structural control systems. A new robust control system is proposed for control of an active tuned mass damper (AMD) in a high-rise building. The controller comprises a two-loop sliding model controller in conjunction with a dynamic state predictor. The sliding model controller is responsible for model uncertainties and the state predictor compensates for the time delays due to actuator dynamics and process delay. A reduced model that is validated against experimental data was constructed and equipped with an electro-mechanical AMD system mounted on the top storey. The proposed controller was implemented in the test structure and its performance under seismic disturbances was simulated using a seismic shake table. Moreover, robustness of the proposed controller was examined via variation of the test structure parameters. The shake table test results reveal the effectiveness of the proposed controller at tackling the simulated disturbances in the presence of model uncertainties and input delay.


2004 ◽  
Vol 269 (1-2) ◽  
pp. 197-211 ◽  
Author(s):  
Jeffrey L. Dohner ◽  
James P. Lauffer ◽  
Terry D. Hinnerichs ◽  
Natarajan Shankar ◽  
Mark Regelbrugge ◽  
...  

1994 ◽  
Author(s):  
Stephen D. O'Regan ◽  
J. Miesner ◽  
R. Aiken ◽  
A. Packman ◽  
Erdal A. Unver ◽  
...  

1999 ◽  
Author(s):  
Sungsoo Na ◽  
Liviu Librescu

Abstract A study of the dynamical behavior of aircraft wings modeled as doubly-tapered thin-walled beams, made from advanced anisotropic composite materials, and incorporating a number of non-classical effects such as transverse shear, and warping inhibition is presented. The supplied numerical results illustrate the effects played by the taper ratio, anisotropy of constituent materials, transverse shear flexibility, and warping inhibition on free vibration and dynamic response to time-dependent external excitations. Although considered for aircraft wings, this analysis and results can be also applied to a large number of structures such as helicopter blades, robotic manipulator arms, space booms, tall cantilever chimneys, etc.


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