scholarly journals A Versatile Flexible Polymer Actuator System for Pumps, Valves, and Injectors Enabling Fully Disposable Active Microfluidics

2020 ◽  
Vol 6 (1) ◽  
pp. 2000769
Author(s):  
Yong Zhong ◽  
Daniel Filippini ◽  
Edwin W. H. Jager
Author(s):  
Gianluca Rizzello ◽  
Micah Hodgins ◽  
David Naso ◽  
Alexander York ◽  
Stefan Seelecke

This paper presents a dynamic electromechanical model for an actuator system based on a Dielectric Electro-Active Polymer (DEAP) membrane biased with a linear spring. The motion is generated by the deformation of the membrane caused by the electrostatic compressive force between two compliant electrodes applied on the surface of the polymer. A mass and a linear spring are used to pre-load the membrane, allowing stroke in the out-of-plane direction. The development of mathematical models which accurately describe the nonlinear system dynamics is a fundamental step in order to design model-based, high-precision position control algorithms. In particular, knowledge of the nonlinear electrical dynamics of the actuator driving circuit can be exploited during the control system design in order to achieve desirable features, such as self-sensing or control energy minimization. This work proposes an electromechanical physical model of the DEAP actuator system. By means of numerous experiments, it is shown that the model can be used to predict the current by measuring deformation and voltage (electrical dynamics), as well as predicting deformation and current by measuring the voltage (electromechanical dynamics).


Kobunshi ◽  
1999 ◽  
Vol 48 (3) ◽  
pp. 142-142
Author(s):  
Shingo SEWA

1993 ◽  
Vol 58 (10) ◽  
pp. 2290-2304 ◽  
Author(s):  
Zuzana Limpouchová ◽  
Karel Procházka

Monte Carlo simulations of chain conformations in a restricted spherical volume at relatively high densities of segments were performed for various numbers of chains, N, and chain lengths (number of segments), L, on a tetrahedral lattice. All chains are randomly end-tethered to the surface of the sphere. A relatively uniform surface density of the tethered ends is guaranteed in our simulations. A simultaneous self-avoiding walk of all chains creates starting conformations for a subsequent equilibration. A modified algorithm similar to that of Siepmann and Frenkel is used for the equilibration of the chain conformations. In this paper, only a geometrical excluded volume effect of segments is considered. Various structural and conformational characteristics, e.g. segment densities gS(r), free end densities gF(r) as functions of the position in the sphere (a distance from the center), distributions of the tethered-to-free end distances, ρTF(rTF), etc. are calculated and their physical meaning is discussed. The model is suitable for studies of chain conformations is swollen cores of multimolecular block copolymer micelles and for interpretation of non-radiative excitation energy migration in polymeric micellar systems.


Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1011
Author(s):  
Dimitre Z. Dimitrov ◽  
Zih Fan Chen ◽  
Vera Marinova ◽  
Dimitrina Petrova ◽  
Chih Yao Ho ◽  
...  

In this work, highly conductive Al-doped ZnO (AZO) films are deposited on transparent and flexible muscovite mica substrates by using the atomic layer deposition (ALD) technique. AZO-mica structures possess high optical transmittance at visible and near-infrared spectral range and retain low electric resistivity, even after continuous bending of up to 800 cycles. Structure performances after bending tests have been supported by atomic force microscopy (AFM) analysis. Based on performed optical and electrical characterizations AZO films on mica are implemented as transparent conductive electrodes in flexible polymer dispersed liquid crystal (PDLC) devices. The measured electro-optical characteristics and response time of the proposed devices reveal the higher potential of AZO-mica for future ITO-free flexible optoelectronic applications.


2021 ◽  
Vol 6 (2) ◽  
pp. 2775-2782
Author(s):  
Sen Wang ◽  
Hongxin Huang ◽  
Hailin Huang ◽  
Bing Li ◽  
Ke Huang
Keyword(s):  

Actuators ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 154
Author(s):  
Bin Wang ◽  
Pengda Ren ◽  
Xinhao Huang

A piston piezoelectric (PZT) pump has many advantages for the use of light actuators. How to deal with the contradiction between the intermittent oil supplying and position control precision is essential when designing the controller. In order to accurately control the output of the actuator, a backstepping sliding-mode control method based on the Lyapunov function is introduced, and the controller is designed on the basis of establishing the mathematical model of the system. The simulation results show that, compared with fuzzy PID and ordinary sliding-mode control, backstepping sliding-mode control has a stronger anti-jamming ability and tracking performance, and improves the control accuracy and stability of the piezoelectric pump-controlled actuator system.


2021 ◽  
Vol 18 (1) ◽  
pp. 172988142199399
Author(s):  
Xiaoguang Li ◽  
Bi Zhang ◽  
Daohui Zhang ◽  
Xingang Zhao ◽  
Jianda Han

Shape memory alloy (SMA) has been utilized as the material of smart actuators due to the miniaturization and lightweight. However, the nonlinearity and hysteresis of SMA material seriously affect the precise control. In this article, a novel disturbance compensation-based adaptive control scheme is developed to improve the control performance of SMA actuator system. Firstly, the nominal model is constructed based on the physical process. Next, an estimator is developed to online update not only the unmeasured system states but also the total disturbance. Then, the novel adaptive controller, which is composed of the nominal control law and the compensation control law, is designed. Finally, the proposed scheme is evaluated in the SMA experimental setup. The comparison results have demonstrated that the proposed control method can track reference trajectory accurately, reject load variations and stochastic disturbances timely, and exhibit satisfactory robust stability. The proposed control scheme is system independent and has some potential in other types of SMA-actuated systems.


Sign in / Sign up

Export Citation Format

Share Document