Stretching the Boundary- Shell Finite Elements of Pneumatic Soft Actuators

Highlights

• We simulate the deformation behavior of 12 pneumatic soft actuators using two finite element simulation methods: using traditional volumetric elements, and using dimensionally reduced shell finite elements.
• We compare computational cost of each simulation and present a local accuracy metric for quantifying precision of shell simulations relative to volumetric simulations
• We find that simulations over shell finite elements execute ~7x faster, with acceptable loss in accuracy!

Two Simulation Options

We simulate pneumatic soft actuators like the bending actuator show at left using shell finite elements, as well as volumetric finite elements. We then measure the accuracy of shell simulations by computing the local L2 norm of the difference in position between corresponding points on the actuators’ outer surfaces.

A Variety of Designs

We simulate the behavior of actuators that exhibit bending, extension, twisting, and compound deformation modes.