Implementation and Control of a Rotary Manipulator Driven by Soft Dielectric Electroactive Polymer

Abstract:

Dielectric Electroactive Polymers (EAPs) are closest to natural muscles in terms of strain, energy density, efficiency and speed. A 2-DOF (Degree of Freedom) rotary manipulator driven by soft dielectric EAP is designed based on the biological agonist–antagonist configuration. Compact rolled actuators are chosen and implemented to drive the manipulator. To avoid the complicated solving of nonlinear differential equations, electromechanical characteristics of actuators are obtained by measuring their force behavior under different voltages and lengths. A CMAC (Cerebellar model articulation controller) neural network-based closed loop controller is developed to implement the position control of the manipulator and is evaluated by tracking a circle. According to the force analysis of the manipulator, forces of antagonistic actuators are determined by force decomposition to produce the desired force output, and then the voltages for actuators at certain lengths can be calculated through measured electromechanical characteristics. Experiment shows the measured force agrees well with the desired force. Due to the advantages of dielectric EAP, the manipulator has application prospects in areas of rehabilitation, force feedback or flexible manipulation without damage.

• Periodical: Applied Mechanics and Materials (Volume 461)
• Pages: 352-357
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.461.352
• Online since: November 2013
• Authors: Hua Ming Wang, Hua An Luo, Bin Yang
• Keywords: Control, Dielectric EAP Actuator, Manipulator

References

[1] G. Kofod, Dielectric Elastomer Actuators, Ph. D Thesis. Department of Chemistry, The Technical University of Denmark, (2001).

[2] R. Pelrine, R. Kornbluh, Q. Pei, J. Joseph, High-Speed Electrically Actuated Elastomers with Strain Greater Than 100%, SCIENCE 287 (2000) 836-839.

DOI: 10.1126/science.287.5454.836

[3] F. Carpi, D. De Rossi, R. Kornbluh, R. Pelrine, P. Sommer-Larsen, Dielectric Elastomers as Electromechanical Transducers Fundamentals, Materials, Devices, Models and Applications of an Emerging Electroactive Polymer Technology, Elsevier Press, Amsterdam, the Netherlands, (2008).

DOI: 10.1016/b978-0-08-047488-5.00033-2

[4] Y. Bar-Cohen, Electroactive Polymer (EAP) Actuators as Artificial Muscles - Reality, Potential, and Challenges, 2nd ed. SPIE, Bellingham, USA, (2004).

DOI: 10.1117/3.547465

[5] D. Trivedi, C.D. Rahn, W.M. Kier, I.D. Walker, Soft robotics: Biological inspiration, state of the art, and future research, Applied Bionics and Biomechanics 5 (2008) 99-117.

DOI: 10.1080/11762320802557865

[6] E. Biddiss, T. Chau, Dielectric elastomers as actuators for upper limb prosthetics: Challenges and opportunities, Medical Engineering & Physics 30 (2008) 403-18.

DOI: 10.1016/j.medengphy.2007.05.011

[7] I.M. Koo, K. Jung, J.C. Koo, J.D. Nam, Y.K. Lee, H.R. Choi, Development of Soft-Actuator-Based Wearable Tactile Display, IEEE TRANSACTIONS ON ROBOTICS 24 (2008) 549-558.

DOI: 10.1109/tro.2008.921561

[8] Q. Pei, R. Pelrine, M. Rosenthal, S. Stanford, H. Prahlad, R. Kornbluh, Recent progress on electroelastomer artificial muscles and their application for biomimetic robots, Proceedings of SPIE Smart Structures and Materials: Electroactive Polymer Actuators and Devices, San Diego, California, March 14-18, 2004, 5385 (2004).

DOI: 10.1117/12.540462

[9] J.S. Plante, K. Tadakuma, L.M. DeVita, D.F. Kacher, J.R. Roebuck, S.P. DiMaio, F.A. Jolesz, S. Dubowsky, An MRI-Compatible Needle Manipulator Concept Based on Elastically Averaged Dielectric Elastomer Actuators for Prostate Cancer Treatment: An Accuracy and MR-Compatibility Evaluation in Phantoms, Journal of Medical Devices 3 (2009).

DOI: 10.1115/1.3191729

[10] P. Lochmatter, G. Kovacs, Design and characterization of an actively deformable shell structure composed of interlinked active hinge segments driven by soft dielectric EAPs, Sensors and Actuators A 141 (2008) 588–597.

DOI: 10.1016/j.sna.2007.10.030

[11] G. Kovacs, P. Lochmatter, M. Wissler, An arm wrestling robot driven by dielectric elastomer actuators, SMART MATERIALS AND STRUCTURES 16 (2007) S306–S317.

DOI: 10.1088/0964-1726/16/2/s16

[12] M. Randazzo, M. Fumagalli, G. Metta, G. Sandini, Closed loop control of a rotational joint driven by two antagonistic dielectric elastomer actuators, Proceedings of SPIE Electroactive Polymer Actuators and Devices, San Diego, California, March 8-11, 2010, 7642 (2010).

DOI: 10.1117/12.847372

[13] Y.L. Zhu, H.M. Wang, D.B. Zhao, J. Zhao, Energy conversion analysis and performance research on a cone-type dielectric electroactive polymer generator, SMART MATERIALS AND STRUCTURES 20 (2011) 115022.

DOI: 10.1088/0964-1726/20/11/115022

[14] C.C. Lin, F.C. Chen, Improved CMAC neural network control scheme, Electronics Letters 35(2) (1999) 157-158.

DOI: 10.1049/el:19990083