Bio-Inspired Design of Artificial Striated Muscles Composed of Sarcomere-Like Contraction Units (preprint)

TL;DR

This paper presents a bio-inspired artificial muscle design mimicking skeletal muscle striations, combining stretchable and inextensible materials, with a mathematical model and experimental validation demonstrating its performance.

Contribution

It introduces a novel pneumatic artificial muscle with sarcomere-like contraction units and provides a predictive model validated by experiments.

Findings

The artificial muscle can be tuned by geometric parameters and number of units.

The mathematical model accurately predicts force output based on pneumatic pressure.

Experimental results confirm the effectiveness of the bio-inspired design.

Abstract

Biological muscles have always attracted robotics researchers due to their efficient capabilities in compliance, force generation, and mechanical work. Many groups are working on the development of artificial muscles, however, state-of-the-art methods still fall short in performance when compared with their biological counterpart. Muscles with high force output are mostly rigid, whereas traditional soft actuators take much space and are limited in strength and producing displacement. In this work, we aim to find a reasonable trade-off between these features by mimicking the striated structure of skeletal muscles. For that, we designed an artificial pneumatic myofibril composed of multiple contraction units that combine stretchable and inextensible materials. Varying the geometric parameters and the number of units in series provides flexible adjustment of the desired muscle operation. We derived a mathematical model that predicts the relationship between the input pneumatic pressure and the generated output force. A detailed experimental study is conducted to validate the performance of the proposed bio-inspired muscle.