Mechanical Programming of Soft Actuators by Varying Fiber Angle

TLDR

The study investigates how fiber angle influences axial extension, radial expansion, and twisting of fiber‑reinforced soft fluidic actuators under varying input pressure. Finite‑element simulations across a range of fiber angles were performed and experimentally validated, and actuator segments were combined in series to tailor motion combinations for specific tasks. Using the simulation results, a segmented worm‑like soft robot was designed that can propel itself through a tube and perform orientation‑specific peg insertion, illustrating that knowledge of fiber‑angle response facilitates rapid design of soft robotic devices such as endoscopes and pipe‑inspection tools.

Abstract

In this work we investigate the influence of fiber angle on the deformation of fiber-reinforced soft fluidic actuators and examine the manner in which these actuators extend axially, expand radially and twist about their axis as a function of input pressure. We study the quantitative relationship between fiber angle and actuator deformation by performing finite element simulations for actuators with a range of different fiber angles, and we verify the simulation results by experimentally characterizing the actuators. By combining actuator segments in series, we can achieve combinations of motions tailored to specific tasks. We demonstrate this by using the results of simulations of separate actuators to design a segmented wormlike soft robot capable of propelling itself through a tube and performing an orientation-specific peg insertion task at the end of the tube. Understanding the relationship between fiber angle and pressurization response of these soft fluidic actuators enables rapid exploration of the design space, opening the door to the iteration of exciting soft robot concepts such as flexible and compliant endoscopes, pipe inspection devices, and assembly line robots.