Electrostatic Behavior of Dielectric Elastomer Actuators with Discrete Electrodes

Over the past couple of years, the field of soft robotics has seen tremendous expansion. As humans are looking towards a more collaborative, symbiotic relationship robots, actuators that are compliant and that do not employ a rigid frame are essential. One type of actuator that is currently being proposed is the Dielectric Elastomer Actuator (DEA), which use Coulomb force of attraction between two electrodes to generate motion. DEAs are often referred to as artificial biological muscle because they share many of the properties of biological muscle (high energy density, compliance, natural damper). However, they do have some severe limitations that prevent their use in commercial applications, the most severe of limitations is that DEAs require very high voltages to operate (order of kilovolts). The possibility of lowering the actuation voltage seems to have been overlooked in the literature. In this research project, a solution to this problem is investigated, using multiple segments, instead of one continuous electrode. The major component being investigated is the geometry of the actuator as it relates to the behavior of the actuator and its actuation voltage. Two sets of actuators with different geometries were investigates, three identical versions of each actuator were manufactured, and all were tested below 7,000 volts. Video recordings were acquired between each voltage step, each were then processed and position data for the actuator was extracted for analysis. The main findings for this research showed that when the overall electro-active area was conserved, it was possible to manufacture multi-segmented dielectric elastomer actuators (MSDEAs) that performed better than its non-segmented counterpart. Segmented electrodes pave the way towards a new class of DEA. Those new actuators have the potential of being implantable inside of the human body, allowing for a new class of assistive prosthetics to be developed