Dynamical Modeling and Control of Soft Robots with Non-constant Curvature Deformation

TL;DR

This paper introduces a 3D modeling approach for multi-segment soft robots with non-constant curvature, improving dynamic control and accuracy over traditional PCC models, validated through simulations and experiments.

Contribution

A novel 3D modeling method for soft robots with non-constant curvature and two controllers for dynamic trajectory and pose control are proposed.

Findings

Model achieves higher accuracy in dynamic tasks.

Controllers enable stable trajectory tracking at high speeds.

Experimental validation confirms effectiveness of the approach.

Abstract

The Piecewise Constant Curvature (PCC) model is the most widely used soft robotic modeling and control. However, the PCC fails to accurately describe the deformation of the soft robots when executing dynamic tasks or interacting with the environment. This paper presents a simple threedimensional (3D) modeling method for a multi-segment soft robotic manipulator with non-constant curvature deformation. We devise kinematic and dynamical models for soft manipulators by modeling each segment of the manipulator as two stretchable links connected by a universal joint. Based on that, we present two controllers for dynamic trajectory tracking in confguration space and pose control in task space, respectively. Model accuracy is demonstrated with simulations and experimental data. The controllers are implemented on a four-segment soft robotic manipulator and validated in dynamic motions and pose control with unknown loads. The experimental results show that the dynamic controller enables a stable reference trajectory tracking at speeds up to 7m/s.