Compliant polymeric actuation technologies such as dielectric elastomers (DEs) enable a new generation of fully soft mobile robots to be developed that can operate in complex, constricted environments. These technologies have the potential to greatly improve performance in application domains such as minimally-invasive surgery and machine inspection since soft robots can actively and/or passively deform to reduce stresses in surrounding structures. However, this compliance adds significant complexity to the challenge of predicting their behaviour. In this work a hyperelastic electro-mechanical model is developed for a soft inchworm robot that incorporates pneumatically coupled DE membranes. The non-linear model has been validated against experimental data of inchworm segments with VHB 4905 DE actuators and demonstrates good correlation across a range of drive parameters. The model can also illustrate and characterize the complex non-linear relationship between drive voltage, pneumatic pressure and active stroke, which fundamentally underpins locomotion performance of the soft inchworm robot. Finally, the model is used to predict future performance limits of a two-segment soft robot, which has experimentally demonstrated a locomotion speed of 2.5 body lengths per minute.
|Title of host publication||Proceedings of Fourth international conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles|
|Publication status||Published - 11 Jun 2014|