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Progress Toward Robust Polymer Hydrogels, Sina Naficy, Hugh Brown, Joselito Razal, Geoffrey Spinks, Philip Whitten
Progress Toward Robust Polymer Hydrogels, Sina Naficy, Hugh Brown, Joselito Razal, Geoffrey Spinks, Philip Whitten
Sina Naficy
In this review we highlight new developments in tough hydrogel materials in terms of their enhanced mechanical performance and their corresponding toughening mechanisms. These mechanically robust hydrogels have been developed over the past 10 years with many now showing mechanical properties comparable with those of natural tissues. By first reviewing the brittleness of conventional synthetic hydrogels, we introduce each new class of tough hydrogel: homogeneous gels, slip-link gels, double-network gels, nanocomposite gels and gels formed using poly-functional crosslinkers. In each case we provide a description of the fracture process that may be occurring. With the exception of double network gels …
Development Of A Dry Actuation Conducting Polymer Actuator For Micro-Optical Zoom Lenses, Baek-Chul Kim, Hyunseok Kim, Chuc Nguyen, M Cho, Yesung Lee, Jae-Do Nam, Hyouk Choi, Jachoon Koo, H-S Jeong
Development Of A Dry Actuation Conducting Polymer Actuator For Micro-Optical Zoom Lenses, Baek-Chul Kim, Hyunseok Kim, Chuc Nguyen, M Cho, Yesung Lee, Jae-Do Nam, Hyouk Choi, Jachoon Koo, H-S Jeong
Chuc Huu Nguyen
The objective of the present work is to demonstrate the efficiency and feasibility of NBR (Nitrile Butadiene Rubber) based conducting polymer actuator that is fabricated into a micro zoon lens driver. Unlike the traditional conducting polymer that normally operates in a liquid, the proposed actuator successfully provides fairly effective driving performance for the zoom lens system in a dry environment. And this paper is including the experiment results for an efficiency improvement. The result suggested by an experiment was efficient in micro optical zoom lens system. In addition, the developed design method of actuator was given consideration to design the …
Modelling Trilayer Conjugated Polymer Actuators For Their Sensorless Position Control, Chuc Nguyen, Gursel Alici, G Wallace
Modelling Trilayer Conjugated Polymer Actuators For Their Sensorless Position Control, Chuc Nguyen, Gursel Alici, G Wallace
Chuc Huu Nguyen
In this paper, we present a new model to describe the displacement response of a trilayer conjugated polymer actuator that can operate in dry environments. The proposed model based on the working principle of conjugated polymer actuators includes diffusion impedances combined with double layer capacitors and charge transfer resistors. The parameters of the model are estimated by using a nonlinear least square estimation method by comparing simulation and experimental results. The proposed model is very useful in predicting the impedance as well as the displacement response of the polymer actuators accurately. Based on the proposed model, an inversion-based controller not …
Adaptive Sliding Mode Control Of Tri-Layer Conjugated Polymer Actuators, Xiangjiang Wang, Gursel Alici, Chuc Nguyen
Adaptive Sliding Mode Control Of Tri-Layer Conjugated Polymer Actuators, Xiangjiang Wang, Gursel Alici, Chuc Nguyen
Chuc Huu Nguyen
This paper proposes an adaptive sliding mode control methodology to enhance the positioning ability of conducting polymer actuators typified by tri-layer conjugated polymer actuators. This is motivated by the search for an effective control strategy to command such actuators to a desired configuration in the presence of parametric uncertainties and unmodeled disturbances. After analyzing the stability of the adaptive sliding mode control system, experiments were conducted to demonstrate its satisfactory tracking ability, based on a series of experimental results. Implementation of the control law requires a valid model of the conducting polymer actuator and boundaries of the uncertainties and disturbances. …
Progress Toward Robust Polymer Hydrogels, Sina Naficy, Hugh Brown, Joselito Razal, Geoffrey Spinks, Philip Whitten
Progress Toward Robust Polymer Hydrogels, Sina Naficy, Hugh Brown, Joselito Razal, Geoffrey Spinks, Philip Whitten
Sina Naficy
In this review we highlight new developments in tough hydrogel materials in terms of their enhanced mechanical performance and their corresponding toughening mechanisms. These mechanically robust hydrogels have been developed over the past 10 years with many now showing mechanical properties comparable with those of natural tissues. By first reviewing the brittleness of conventional synthetic hydrogels, we introduce each new class of tough hydrogel: homogeneous gels, slip-link gels, double-network gels, nanocomposite gels and gels formed using poly-functional crosslinkers. In each case we provide a description of the fracture process that may be occurring. With the exception of double network gels …