3D-printed biomimetic artificial muscles using soft actuators that contract and elongate

Abstract

Biomimetic machines able to integrate with natural and social environments will find ubiquitous applications, from biodiversity conservation to elderly daily care. Although artificial actuators have reached the contraction performances of muscles, the versatility and grace of the movements realized by the complex arrangements of muscles remain largely unmatched. Here, we present a class of pneumatic artificial muscles, named GeometRy-based Actuators that Contract and Elongate (GRACE). The GRACEs consist of a single-material pleated membrane and do not need any strain-limiting elements. They can contract and extend by design, as described by a mathematical model, and can be realized at different dimensional scales and with different materials and mechanical performances, enabling a wide range of lifelike movements. The GRACEs can be fabricated through low-cost additive manufacturing and even built directly within functional devices, such as a pneumatic artificial hand that is fully three-dimensionally printed in one step. This makes the prototyping and fabrication of pneumatic artificial muscle–based devices faster and more straightforward.

Transfer printing technologies for soft electronics

“…[80][81][82] Soft actuators are widely used in the area of artificial muscles, robotics, and haptic systems. [83][84][85] By combining functional materials and transfer printing technology, various soft functions can be achieved, such as mechanical bending, 86,87 drug delivery, 88,89 and temperature management. 90,91 Xinge Yu et al reported a skin-integrated haptic interface system for virtual and augmented reality (Fig.…”

Cell Differentiation-Inspired, Salt-Induced Multifunctional Gels for an Intelligent Soft Robot with an Artificial Reflex Arc

“…The emulation of this process becomes a promising technology in bioinspired electronics for intelligent robotics. For example, to produce the bionic electric skin, there are numerous skilled designs in both structure and materials for accurate and efficient stimuli sensing. − Meanwhile, various artificial muscles based on asymmetric expansion, , pneumatic inflation, − and hydraulic actuation , with specific system programming were developed, for instance. Consequently, in terms of mimicking biological conditioned reflex, which receives external stimuli and produces informative synaptic-responsive and motor outputs, the complex and incompatible production processes of electric skins and artificial muscles lead to high production costs and delicate preparation of intelligent robotics. , Therefore, one of the key challenges in the field of commercial intelligent soft robotics construction is developing a kind of novel multifunctional intelligent material for an efficient manufacturing process.…”

High‐Speed and Low‐Energy Actuation for Pneumatic Soft Robots with Internal Exhaust Air Recirculation

“…[ 16,41 ] Therefore, achieving high‐speed and low‐energy actuation of m‐SPAs remains an open challenge (Table S1 and Figure S1a, Supporting Information). [ 13,14,18,22,34,42–47 ]…”