A recursive dynamics algorithm for soft robotic manipulators made of viscoelastic material

Abstract

In recent years, research and development of robots that exist in the same space as humans and can collaborate with humans have been actively carried out. If the body of a robot is made of a hard material, it may cause injury. Therefore, attempts have been made to make a robot with a soft body using rubber or resin. In order to accelerate such research on soft robotics, it is necessary to establish fast and stable simulation algorithm for robots containing viscoelastic bodies such as rubber and resin. Therefore, in this study, we consider to approximate viscoelastic bodies with finite rigid body segments and connect them with joints and linear viscoelastic elements such as Voigt model and Maxwell model to approximate viscoelastic properties. The recursive dynamics algorithm is used to speed up the calculation, and the generalization-a method is used to stabilize the numerical integration. In particular, we propose a new method on how to incorporate the Maxwell model into recursive dynamics algorithm and generalization-a method. The effectiveness of the proposed method is confirmed by some numerical examples.