Modeling and Characterization of Tensegrity Structures Integrating Dielectric Elastomer Actuators

Tensegrity structures, architectures that consist of elastic cables and rigid rods, have attracted attention as a building block of robots because of their compliance, lightweight properties, and mechanical robustness. This article describes a method to create electroactive tensegrity structures that employs a dielectric elastomer actuator (DEA) as the actuation principle. Two different types of DEA-tensegrities are considered herein: a membrane type and a cable type. In these devices, DEAs are made of an acrylic elastomer (3 m, VHB 4905) and a stretchable conductive film (Adhesives Research, ARcare 90336) used as dielectric and electrode layers, respectively. An analytical model of DEA-tensegrities is built that guides the fabrication of experimental devices. The fabricated DEA-tensegrities are characterized by the actuation strain in the height direction. As a result, voltage-controlled actuation strains of 7.5% and 2.0% are observed at 10 kV for membrane type and cable type DEA-tensegrity, respectively, while the model prediction captures the actuation characteristics.