Dielectric elastomer bender actuator applied to modular robotics

This paper addresses the miniaturization of the modules of a modular robot - a major challenge in the field. State of the art modules typically use electromagnetic motors for mobility and self-reconfiguration. However, electromagnetic motor performance reduces upon downscaling to the mesoscale. The smallest self-contained module uses shape memory alloy which is inherently inefficient, slow, and difficult to position control. This work surveys available actuation technologies with respect to appropriate figures of merit. It concludes that dielectric elastomer actuation is promising. We present the design and experimental analysis of an agonist-antagonist dielectric elastomer actuator configuration 7 times smaller than previously demonstrated. Demonstrations with two modules show module bending up to 15° in various modular robot morphologies. In addition, we demonstrate parallel actuation: a pair of modules acting in parallel can lift twice the load a single module can.