Dielectric elastomer actuators (DEAs) are a promising technology for soft robotics. The use of DEAs has many advantages, including light weight, resilience, and fast response for its applications, such as grippers, artificial muscles, and heel strike generators. Grippers are commonly used as grasping devices. In this study, we focus on DEA applications and propose a technology to expand the applicability of a soft gripper. The advantages of gripper-based DEAs include light weight, fast response, and low cost. We fabricated soft grippers using multiple DEA layers. The grippers successfully held or gripped an object, and we investigated the response time of the grippers and their angle characteristics. We studied the relationship between the number of DEA layers and the performance of our grippers. Our experimental results show that the multi-layered DEAs have the potential to be strong grippers.

1. [1] A. Murphy, S. Muldoon, D. Baker, A. Lastowka, B. Bennett, M. Yang, and D. Bassett, “Structure, function, and control of the human musculoskeletal network,” PLoS Biol., Vol.16, e2002811, 2018.
2. [2] R. Parry, S. Soria, P. Pradat-Diehl, V. Marchand-Pauvert, N. Jarrasse, and A. Roby-Brami, “Effects of Hand Configuration on the Grasping, Holding, and Placement of an Instrumented Object in Patients with Hemiparesis,” Frontiers in Neurology, Vol.10, 240, 2019.
3. [3] F. Cannella, F. Chen, C. Canali, A. Eytan, A. Bottero, and D. Caldwell, “Design of an Industrial Robotic Gripper for Precise Twisting and Positioning in High-Speed Assembly,” Proc. of the IEEE/SICE Int. Symp. on System Integration, pp. 443-448, 2013.
4. [4] M. Tiboni, F. Aggogeri, R. Bussola, A. Borboni, C. A. Perani, and N. Pellegrini, “Low-Cost Design Solutions for Educational Robots,” J. Robot. Mechatron., Vol.30, No.5, pp. 827-834, 2018.
5. [5] W. Yuzhe, G. Ujjaval, P. Nachiket, and Z. Jian, “A soft gripper of fast speed and low energy consumption,” Science China Technological Sciences, Vol.62, pp. 31-38, 2018.
6. [6] F. Schmitt, O. Piccin, L. Barbé, and B. Bayle, “Soft Robots Manufacturing,” Frontiers in Robotics and AI, Vol.5, No.84, 2018.
7. [7] A. Seibel and L. Schiler, “Systematic engineering design helps creating new soft machines,” Robotics and Biomimetics, Vol.5, 5, 2018.
8. [8] W. Nianfeng, C. Chaoyu, G. Hao, C. Bicheng, and Z. Xianmin, “Advances in dielectric elastomer actuation technology,” Science China Technological Sciences, Vol.61, pp. 1512-1527, 2017.
9. [9] Z. Mao, T. Nagaoka, S. Yokota, and J. Kim, “Soft fiber-reinforced bending finger with three chambers actuated by ECF (Electro-conjugate Fluid) pumps,” Sensors and Actuators, Vol.310, 112034, 2020.
10. [10] M. Adami and A. Seibel, “On-Board Pneumatic Pressure Generation Methods for Soft Robotics Applications,” Actuators, Vol.8, pp. 2-34, 2018.
11. [11] Y. Seki, Y. Kuwajima, H. Shigemune, Y. Yamada, and S. Maeda, “Optimization of the Electrode Arrangement and Reliable Fabrication of Flexible EHD Pumps,” J. Robot. Mechatron., Vol.32, No.5, pp. 939-946, 2020.
12. [12] A. Minaminosono, H. Shigemune, Y. Okuno, T. Katsumata, N. Hosoya, and S. Maeda, “A Deformable Motor Driven by Dielectric Elastomer Actuators and Flexible Mechanisms,” Frontiers in Robotics and AI, Vol.6, No.1, pp. 1-12, 2019.
13. [13] H. Banerjee, M. Suhail, and H. Ren, “Hydrogel Actuators and Sensors for Biomedical Soft Robots: Brief Overview with Impending Challenges,” Biomimetics, Vol.3, No.3, 15, 2018.
14. [14] F. Carpi and D. De Rossi, “Electroactive polymer artificial muscles: an overview,” Design and Nature V, Vol.138, pp. 353-364, 2010.
15. [15] J. Youn, S. Jeong, G. Hwang, H. Kim, K. Hyeon, J. Park, and K. Kyung, “Dielectric Elastomer Actuator for Soft Robotics Applications and Challenges,” Applied Sciences, Vol.10, No.2, 640, 2020.
16. [16] A. Srivastava and S. Basu, “Modelling the performance of devices based on thin dielectric elastomer membranes,” Mechanics of Materials, Vol.137, 103136, 2019.
17. [17] A. Wiranata, Y. Ishii, H. Hosoya, and S. Maeda, “Simple and Reliable Fabrication Method for PDMS Dielectric Elastomer Actuators using Carbon Nanotube Powder Electrodes,” Advanced Engineering Materials, Vol.23, 2001181, 2021.
18. [18] M. Corbaci, W. Walter, and K. Lamkin-Kennard, “Implementation of Soft-Lithography Techniques for Fabrication of Bio-Inspired Multi-Layer Dielectric Elastomer Actuators with Interdigitated Mechanically Compliant Electrodes,” Actuators, Vol.7, 73, 2018.
19. [19] J. Shintake, S. Rosset, B. Schubert, D. Floreano, and H. Shea, “Versatile Soft Grippers with Intrinsic Electroadhesion Based on Multifunctional Polymer Actuators,” Advanced Materials, Vol.28, pp. 231-238, 2016.
20. [20] H. Shigemune, S. Suganoi, J. Nishitani, M. Yamauchi, N. Hosoya, S. Hashimoto, and S. Maeda, “Dielectric Elastomer Actuators with Carbon Nanotube Electrodes Painted with a Soft Brush,” Actuators, Vol.7, No.3, 51, 2018.
21. [21] N. Hashimoto, H. Shigemune, A. Minaminosono, S. Maeda, and H. Sawada, “Self-Assembled 3D Actuator Using the Resilience of an Elastomeric Material,” Frontiers in Robotics and AI, Vol.6, 152, 2020.
22. [22] I. Anderson, T. Gisby, T. McKay, B. O’Brien, and E. Calius, “Multi-functional dielectric elastomer artificial muscles for soft and smart machines,” J. of Applied Physics, Vol.112, 041101, 2012.
23. [23] G. Lau, T. La, E. Foong, and M. Shrestha, “Stronger multilayer acrylic dielectric elastomer actuators with silicone gel coatings,” Smart Materials and Structures, Vol.25, 125006, 2016.
24. [24] M. Mehnert and P. Steinmann, “On the influence of the compliant electrodes on the mechanical behavior of VHB 4905,” Computational Materials Science, Vol.160, pp. 287-294, 2019.
25. [25] S. Shian, K. Bertoldi, and D. Clarke, “Dielectric Elastomer Based “Grippers” for Soft Robotics,” Advanced Materials, Vol.27, pp. 6814-6819, 2015.