Leveraging Elastic instabilities for Amplified Performance: spine-inspired high-speed and high-force soft robots

TL;DR

This paper introduces a novel design principle for soft robots that uses mechanical instabilities to achieve high speed and force, inspired by biological spines, enabling rapid energy release and multifunctionality.

Contribution

It presents a generic approach leveraging tunable snap-through bistability to enhance the performance of soft robots across various applications.

Findings

Achieved 2.68 body length/s speed in cheetah-like crawlers

Developed underwater swimmers with 0.78 body length/s speed

Created tunable soft grippers with over 103 stiffness modulation

Abstract

Soft machines typically exhibit slow locomotion speed and low manipulation strength because of intrinsic limitations of soft materials. Here, we present a generic design principle that harnesses mechanical instability for a variety of spine-inspired fast and strong soft machines. Unlike most current soft robots that are designed as inherently and unimodally stable, our design leverages tunable snap-through bistability to fully explore the ability of soft robots to rapidly store and release energy within tens of milliseconds. We demonstrate this generic design principle with three high-performance soft machines: High-speed cheetah-like galloping crawlers with locomotion speeds of 2.68 body length/s, high-speed underwater swimmers (0.78 body length/s), and tunable low-to-high-force soft grippers with over 1 to 103 stiffness modulation (maximum load capacity is 11.4 kg). Our study establishes a new generic design paradigm of next-generation high-performance soft robots that are applicable for multifunctionality, different actuation methods, and materials at multiscales.