Document Type : Original Article


Department of Mechanical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran


Dielectric elastomer actuators are capable of creating multi degrees of freedom in a single joint. In this paper, a double-cone dielectric elastomer actuator is assumed as a planar joint with two degrees of freedom. Because of theoretical complexities, mathematical formulation of dynamic equations is too complicated. To obtain the dynamic equations of motion, at first, experimental charts are used. At this stage forms of relations between displacements, voltages, forces and moments are proposed, and coefficients are optimized to keep the difference between experimental and estimated charts in minimum. Then dynamic equations of motion are derived based on Newton-Euler method, and state-space form of equations of the joint are obtained. As a second objective, joint stabilization around working point is considered. To stabilize the joint against external loads, or initial dislocations, a regulator controller is designed. The joint is over actuated. So using constraint equations, control rule is extracted and simulated. Simulations show successful performance around the working point.


Main Subjects

[1]     Jung, K., Kim, K. J. and Choi, H. R., A Self-Sensing Dielectric Elastomer Actuator, Sensors and Actuators A: Physical, Vol. 143, No. 2, pp. 343-351.
[2]     Koo, J. C., Choi, H. R., Jung, M. Y., Jung, K. M., Nam, J. D. and Lee, Y. K., Design and Control of Three-DOF Dielectric Polymer Actuator, Key Engineering Materials, Vol. 297, 2005, pp. 665-670.
[3]     He, T., Zhao, X. and Suo, Z., Equilibrium and Stability of Dielectric Elastomer Membranes Undergoing Inhomogeneous Deformation, Journal of Applied Physics, Vol. 106, No. 8, 083522, pp. 1-28.
[4]     He, T., Cui, L., Chen, C. and Suo, Z., Nonlinear Deformation Analysis of a Dielectric Elastomer Membrane–Spring System, Smart Materials and Structures, Vol. 19, No. 8, 085017, pp. 1-7.
[5]     Luan, Y., Wang, H. and Zhu, Y., Design and Implementation of Cone Dielectric Elastomer Actuator with Double-Slider Mechanism, Journal of Bionic Engineering, Vol. 7, 2010, pp. S212-S217.
[6]     Conn, A. T., Rossiter, J., Antagonistic Dielectric Elastomer Actuator for Biologically-Inspired Robotics, SPIE Smart Structures and Materials+ Nondestructive Evaluation and Health Monitoring, Vol. 7976, 2011, pp. 79761Z1-79761Z10.
[7]     He, T., Miao, G. and Chen, C., The Effect of Pre Stretch on the Performance of a Dielectric Elastomer Membrane, Remote Sensing, Environment and Transportation Engineering (RSETE), Jun. 2011, pp. 6463-6467.
[8]     Conn, A. T., Rossiter, J., Towards Homonymic Electro-Elastomer Actuators with Six Degrees of Freedom, Smart Materials and Structures, Vol. 21, No. 3, 035012, pp. 1-9.
[9]     Branz, F., Sansone, F. and Francesconi, A., Design of an Innovative Dielectric Elastomer Actuator for Space Applications, SPIE Smart Structures and Materials+ Nondestructive Evaluation and Health Monitoring, Vol. 9056, 2014, pp. 90560Z1-90560Z10.
[10]  Branz, F., Antonello, A., Carron, A., Carli, R. and Francesconi, A., Kinematics and Control of Redundant Robotic Arm Based on Dielectric Elastomer Actuators, SPIE Smart Structures and Materials+ Nondestructive Evaluation and Health Monitoring, Vol. 9430, 2015, 943023, pp. 1-13.
[11]  Branz, F., Francesconi, A., Modelling and Control of Double-Cone Dielectric Elastomer Actuator, Smart Materials and Structures, Vol. 25, No. 9, pp. 095040.
[12]  Wang, P., Conn, A. T., Elastic Cube Actuator with Six degrees of Freedom Output, Actuators Vol. 4, No. 3, pp. 203-216.
[13]  Nguyen, C. T., Phung, H., Nguyen, T. D., Jung, H. and Choi, H. R., Multiple-Degrees-of- Freedom Dielectric Elastomer Actuators for Soft Printable Hexapod Robot, Sensors and Actuators A: Physical, Vol. 267, 2017, pp. 505-516.
[14] Hau, S., York, A. and Seelecke, S., Performanc Eprediction of Circular Dielectric Electro-Active Polymers Membrane Actuators with Various Geometries, Electroactive Polymer Actuators and Devices (EAPAD), Vol. 9430, 2015, pp. 94300C1- 94300C8.