Creating a Softer RoboSquid: Liquid-Metal-Based Compliant Pumps for Pulsed Jet Propulsion
Date
2025-02-28
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Advanced Materials Technologies
Abstract
Soft pumps are a crucial element in biology, from our own hearts to actuators driving the motion of many creatures in nature. For example, the squid is one of the fastest and most powerful animals in the ocean despite being almost entirely soft, using controlled jets by compressing an internal chamber to propel itself rapidly through the water. Duplicating this performance in an artificial system has, however, remained challenging. Here, a novel soft electromagnetic pump based on using coils of room temperature LM (liquid metal) to drive a permanent magnet piston is demonstrated and used to propel a squid-inspired vehicle. Liquid gallium alloys in silicone tubing are used to manufacture a stretchable electromagnet which is then integrated into a silicone bubble and used to actuate an attached permanent magnet. The robosquid here was able to achieve as high as 4.53 cm s−1 (0.65 body lengths/s) and 9.52 cm s−1 (1.38 body lengths/s) average and peak speed respectively, competitive with current squid inspired vehicles integrating rigid motors and actuators. This result is a major milestone in creating high performance pumps for soft robotics, and will enable superior performance of future soft underwater vehicles leveraging biological principles.
Description
This is the peer reviewed version of the following article: J. D. Cortazar, N. Lazarus, Creating a Softer RoboSquid: Liquid-Metal-Based Compliant Pumps for Pulsed Jet Propulsion. Adv. Mater. Technol. 2025, 2401372. https://doi.org/10.1002/admt.202401372 , which has been published in final form at https://doi.org/10.1002/admt.202401372. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.
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Keywords
electromagnetic actuation, liquid metals, pulsed jet propulsion, soft pump, soft robotics
Citation
J. D. Cortazar, N. Lazarus, Creating a Softer RoboSquid: Liquid-Metal-Based Compliant Pumps for Pulsed Jet Propulsion. Adv. Mater. Technol. 2025, 2401372. https://doi.org/10.1002/admt.202401372