A method of tuning viscoelastic creep in charge-controlled dielectric elastomer actuation

¹ State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University Xi'an, 710049, China
² School of Aerospace, Xi'an Jiaotong University - Xi'an, 710049, China
³ Department of Materials Science and Engineering, Henry Samueli School of Engineering and Applied Science, University of California - Los Angeles, CA 90095, USA
⁴ School of Mechanical Engineering, Xi'an Jiaotong University - Xi'an, 710049, China

^(a) hlchen@mail.xjtu.edu.cn (corresponding author)

Received: 24 September 2014
Accepted: 13 November 2014

Abstract

Deformation in charge-controlled dielectric elastomer actuation eliminates pull-in instability, but the performance is affected by dissipative characteristics, such as viscoelasticity and leakage current. This letter focuses on the modeling of the dissipative performance in charge-controlled dielectric elastomer actuation. The effects of the initial surface charge and the ratios between viscoelastic relaxation time and resistor-capacitor time constant are investigated. By spraying charge to compensate the leakage and adjusting the surface charge, the viscoelastic relaxation is dispelled and the invariable deformation is tuned. The rate of spraying charge to suppress viscoelastic creep is determined by the difference between the value of the leakage current and the rate of the change of the surface charge.