A Compliant Translational Mechanism Based on Dielectric Elastomer Actuators

2014 ◽  
Vol 136 (6) ◽  
Author(s):  
Chuc Huu Nguyen ◽  
Gursel Alici ◽  
Rahim Mutlu
Keyword(s):  
Position Control ◽  
Translational Motion ◽  
Minimum Energy ◽  
Dielectric Elastomer ◽  
Energy Structure ◽  
Driving Voltage ◽  
Experimental Frequency ◽  
Dielectric Elastomer Actuators ◽  
Proposed Model ◽  
Crank Mechanism

This paper reports on a linear actuation mechanism in the form of a parallel-crank mechanism (i.e., double-crank mechanism) articulated with two dielectric elastomer actuators working in parallel that are fabricated as a minimum energy structure. This structure is established by stretching a dielectric elastomer (DE) film (VHB4910) over a polyethylene terephthalate (PET) frame so that the energy released from the stretched DE film is stored in the frame as bending energy. The mechanism can output a translational motion under a driving voltage applied between two electrodes of the DE film. We have proposed visco-elastic models for the DE film and the frame of the actuator so that the mechanical properties of the actuator can more accurately be incorporated into the mechanism model. The proposed model accurately predicts the experimental frequency response of the mechanism at different voltages. In addition, an inversion-based feedforward controller was successfully implemented in order to further validate the proposed model for sensorless position control of the actuators and the parallel-crank mechanism articulated with these actuators.

Phenomena of nonlinear oscillation and special resonance of a dielectric elastomer minimum energy structure rotary joint

2015 ◽  
Vol 106 (13) ◽  
pp. 133504 ◽  
Author(s):  
Jianwen Zhao ◽  
Junyang Niu ◽  
David McCoul ◽  
Zhi Ren ◽  
Qibing Pei
Keyword(s):  
Nonlinear Oscillation ◽  
Minimum Energy ◽  
Dielectric Elastomer ◽  
Energy Structure ◽  
Rotary Joint

Modeling and Actuation Performance Analysis of Conically-Shaped Dielectric Electroactive Polymer Actuator

2014 ◽  
Vol 633-634 ◽  
pp. 250-256
Author(s):  
Yin Long Zhu ◽  
Hong Pin Zhou ◽  
Hua Ming Wang
Keyword(s):  
Dielectric Elastomer ◽  
Force Output ◽  
Energy Potential ◽  
Principal Stresses ◽  
Dielectric Elastomer Actuator ◽  
Design And Optimization ◽  
Dielectric Elastomer Actuators ◽  
Proposed Model ◽  
Polymer Actuator ◽  
Potential Applications

Dielectric elastomer actuators (DEAs) represent one class of electroactive polymers that have already demonstrated excellent performances and show potential applications in many fields. In this paper, we present a simplified conically-shaped dielectric elastomer actuator model to explore the effects of various preloads and actuation voltages on both the actuation displacement and force output of DEA. The strain energy potential of Yeoh is used and the viscoelasticity is also taken into account. Using the developed model, the numerical results of DEA including the actuation displacement, the distribution of the principal stretch ratios and principal stresses in the membrane and the force output can be obtained. With different preloads and actuation voltages, the actuation characteristic of conically-shaped dielectric elastomer actuator is explored experimentally and validates the results determined from the proposed model. The proposed model can be used for the design and optimization of conically-shaped dielectric elastomer actuator.

New Resonance Mode of Dielectric Elastomer Minimum Energy Structure

2016 ◽  
Vol 97 ◽  
pp. 48-56
Author(s):  
Jian Wen Zhao ◽  
Yong Ge ◽  
Shu Wang ◽  
Bo Huang
Keyword(s):  
Minimum Energy ◽  
Bending Moment ◽  
Input Voltage ◽  
Dielectric Elastomer ◽  
Resonance Mode ◽  
Vibrational Amplitude ◽  
Energy Structure ◽  
Rotary Joint ◽  
Nature Frequency ◽  
Voltage Frequency

The dielectric elastomer minimum energy structure (DEMES) can realize large angular deformations by a small voltage-induced strain of the dielectric elastomer, so it is a suitable candidate to make a rotary joint for a soft robot. Driven with an alternating electric field, the joint deformation vibrational frequency follows the input voltage frequency. However, the authors find that if the rotational angel over a negative angle during dynamic response, the resonance mode will be different from the traditional, the vibration with the largest amplitude does not occur while the voltage frequency is equal to natural response frequency of the joint. Rather, the vibrational amplitude will be quite large over a range of other frequencies, at which the voltage frequency is greater than one time of the nature frequency and smaller than two times. This phenomenon was analyzed by relationship between the bending angle, applied voltage and bending moment of the film to the frame on a timeline. This new resonance mode can be applied to some biomimetic soft robots that consist of DEMES rotary joint.

Improved Model for Conical Dielectric Elastomer Actuators With Fewer Electrical Connections

2020 ◽  
Vol 12 (3) ◽  
Author(s):  
Hector Medina ◽  
Carson W. Farmer
Keyword(s):  
Degrees Of Freedom ◽  
Experimental Tests ◽  
Dielectric Elastomer ◽  
Artificial Muscles ◽  
Multiple Degrees Of Freedom ◽  
Dielectric Elastomer Actuators ◽  
Proposed Model ◽  
Robotic Joints ◽  
Improved Model ◽  
Electrical Connections

Abstract Dielectric elastomers (DEs) exhibit remarkable properties that make them stand out among other electroactive polymers. Various types of actuators based on DEs have been used in applications that include artificial muscles, Braille displays, and robotic joints. In particular, conical dielectric elastomer actuators (CDEAs) are very attractive due to their multiple degrees of freedom (DOF) and easiness of construction. In this study, an energy method is used to derive an improved mathematical model for a double-cone dielectric elastomer actuator (DCDEA) capable of predicting horizontal and rotational displacements. To create the model, a new variable is introduced into the equations, the azimuth angle. In addition, a new pattern of electrodes is proposed as a method for achieving five DOF using only half of the electrode connections of traditional DCDEAs. Experimental tests are carried out and used to validate the proposed model. Results show very close agreement. A limiting aspect of the proposed model is that it relies on two experimental correction coefficients. Nonetheless, the model derived provides a means to more accurately implement automatic control to robotic systems that use DCDEAs (work in progress).

Robust Position Control of Dielectric Elastomer Actuators Based on LMI Optimization

2016 ◽  
Vol 24 (6) ◽  
pp. 1909-1921 ◽  
Author(s):  
Gianluca Rizzello ◽  
David Naso ◽  
Biagio Turchiano ◽  
Stefan Seelecke
Keyword(s):  
Position Control ◽  
Dielectric Elastomer ◽  
Lmi Optimization ◽  
Dielectric Elastomer Actuators
Sign in / Sign up

Export Citation Format

Share Document