We present an approach for evaluating the design of Dielectric Elastomer (DE) capacitive pressure sensors on robotic graspers. This approach has used the ANSYS software for Finite Element Method (FEM), along with a MatLab script for calculation of capacitance change. The model has been set up with an axisymmetric indenter and frictionless contact. This study has compared several structured dielectric elastomer (DE) pressure sensors with different sub-surface soft padding thicknesses. The results suggest that: -For padding that is too thin the contact area will be small with localized compression and sensor sensitivity will be compromised by this; -For padding that is very thick compared with the sensor thickness –deformation will be spread over a wider area and the signal sensitivity will be somewhat lower; for a given indenter radius of curvature; -This suggests that there will be an optimal padding thickness for a given contact geometry. The approach developed and presented in the paper will be helpful for sensor soft sensor design for different applications, such as robotics and bio-instrumentational systems, in particular, the design of graspers to identify and pick up different objects.

Date Published: 25 March 2019
PDF: 7 pages
Proc. SPIE 10966, Electroactive Polymer Actuators and Devices (EAPAD) XXI, 109662F (25 March 2019); doi: 10.1117/12.2515283

Published in SPIE Proceedings Vol. 10966:
Electroactive Polymer Actuators and Devices (EAPAD) XXI
Yoseph Bar-Cohen, Editor(s)