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Multilayer dielectric elastomer actuators  have a wide range of potential applications, but their development and commercial implementation have been hindered by existing manufacturing processes. Existing processes are low‐throughput, limited in area, and/or can only process a narrow range of elastomers. This study presents a novel fabrication paradigm that overcomes these challenges: instead of sequentially patterning electrodes directly onto successive elastomer layers, electrode stamps are patterned onto a carrier film in an independent batch‐spray process and the electrodes are then stamp‐transferred onto each elastomer layer. By modularizing the production and assembly of electrodes, a laboratory‐scale implementation of the process achieves a throughput of 15 layers h⁻¹, a maximum electrode size of 300×300 mm, and tuning‐free compatibility with a wide range of elastomers. The batch‐spraying paradigm also provides the unique capability to evaluate and modify electrodes before they are assembled into a multilayer; a method of mechanically treating the electrodes is employed to increase the breakdown strength of Elastosil P7670 devices from 15.7 to 33.5 V µm⁻¹. The electrodes are conductive up to a strain of more than 200% and add negligible stiffness to the multilayer structure. The capabilities of this process to produce useful devices are demonstrated with a large‐area loudspeaker and an actuator with 60 active layers.

Soft robots adapt passively to complex environments due to their inherent compliance, allowing them to interact safely with fragile or irregular objects and traverse uneven terrain. The vast tunability and ubiquity of textiles has enabled new soft robotic capabilities, especially in the field of wearable robots, but existing textile processing techniques (e.g., cut‐and‐sew, thermal bonding) are limited in terms of rapid, additive, accessible, and waste‐free manufacturing. While 3D knitting has the potential to address these limitations, an incomplete understanding of the impact of structure and material on knit‐scale mechanical properties and macro‐scale device performance has precluded the widespread adoption of knitted robots. In this work, the roles of knit structure and yarn material properties on textile mechanics spanning three regimes–unfolding, geometric rearrangement, and yarn stretching–are elucidated and shown to be tailorable across unique knit architectures and yarn materials. Based on this understanding, 3D knit soft actuators for extension, contraction, and bending are constructed. Combining these actuation primitives enables the monolithic fabrication of entire soft grippers and robots in a single‐step additive manufacturing procedure suitable for a variety of applications. This approach represents a first step in seamlessly “printing” conformal, low‐cost, customizable textile‐based soft robots on‐demand.

Numerous animals adapt their stiffness during natural motions to increase efficiency or environmental adaptability. For example, octopuses stiffen their tentacles to increase efficiency during reaching, and several species adjust their leg stiffness to maintain stability when running across varied terrain. Inspired by nature, variable‐stiffness machines can switch between rigid and soft states. However, existing variable‐stiffness systems are usually purpose‐built for a particular application and lack universal adaptability. Here, reconfigurable stiffness‐changing skins that can stretch and fold to create 3D structures or attach to the surface of objects to influence their rigidity are presented. These “jamming skins” employ vacuum‐powered jamming of interleaved, discrete planar elements, enabling 2D stretchability of the skin in its soft state. Stretching allows jamming skins to be reversibly shaped into load‐bearing, functional tools on‐demand. Additionally, they can be attached to host structures with complex curvatures, such as robot arms and portions of the human body, to provide support or create a mold. We also show how multiple skins can work together to modify the workspace of a continuum robot by creating instantaneous joints. Jamming skins thus serve as a reconfigurable approach to creating tools and adapting structural rigidity on‐demand.

Research into new active materials for soft robots has generated promising new thermally responsive materials for functions such as variable stiffness, on‐demand shape change, and actuation. These new thermally responsive materials require a form of addressable thermal control that is compliance‐matched to its host system. In response to this need, this work presents stretchable, addressable heating silicone sheets that can control soft, thermally responsive materials. The sheets are created using layer‐by‐layer deposition of a bulk conductive elastomer that can be Joule heated, with embedded liquid–metal microchannels used as electrodes. This combination allows the bulk, addressed material to be stretched and twisted while in operation. Local, addressable heating is demonstrated in a silicone‐based composite that is capable of cyclic strains of up to 40%, while still self‐heating to over 100 °C. The heating sheets are demonstrated as a thermal control platform in both color changing and stretch‐and‐hold operations using all silicone‐based composites. Additionally, this platform is bonded to a variable‐stiffness polymer that, with its selective heating capability, enables folding at targeted locations.