Modelling the Nonlinear Response of Fibre-reinforced Bending Fluidic Actuators

TL;DR

This paper introduces a comprehensive 3D analytical model for fibre-reinforced Bending Fluidic Actuators that accounts for nonlinearities, pressure effects, and torque variations, aiding design and control of these soft robotic components.

Contribution

It presents the first detailed 3D analytical model incorporating pressure effects and tip torque variations for fibre-reinforced BFAs, enhancing understanding and predictability.

Findings

Model accurately predicts quasi-static response

Includes pressure effects on lateral surface

Accounts for non-constant torque at the tip

Abstract

Soft actuators are receiving increasing attention from the engineering community, not only in research but even for industrial applications. Among soft actuators, fibre-reinforced Bending Fluidic Actuators (BFAs) became very popular thanks to features such as robustness and easy design and fabrication. However, an accurate modelling of these smart structures, taking into account all the nonlinearities involved, is a challenging task. In this effort, we propose an analytical mechanical model to capture the quasi-static response of fibre-reinforced BFAs. The model is fully 3D and for the first time includes the effect of the pressure on the lateral surface of the chamber as well as the non-constant torque produced by the pressure at the tip. The presented model can be used for design and control, while providing information about the mechanics of these complex actuators.