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Storage of elastic energy is key to increasing the efficiency, speed, and power output of many biological systems. This paper describes a simple design strategy for the rapid fabrication of prestressed soft actuators (PSAs), exploiting elastic energy storage to enhance the capabilities of soft robots. The elastic energy that PSAs store in their prestressed elastomeric layer enables the fabrication of grippers capable of zero-power holding up to 100 times their weight and perching upside down from angles of up to 116°. The direction and magnitude of the force used to prestress the elastomeric layer can be controlled not only to define the final shape of the PSA but also to program its actuation sequence. Additionally, the release of the elastic energy stored by PSAs causes their high-speed recovery (≈50 ms), which significantly improves the actuation rates of soft pneumatic actuators, especially after motions requiring large deformations. Moreover, judicious prestressing of PSAs can also create bistable soft robotic systems, which use their stored elastic energy as a source of power amplification for rapid movements. These strategies serve as a basis for a new class of entirely soft robots capable of recreating bioinspired high-powered and high-speed motions using stored elastic energy.

Multifunctional electronic textiles (e-textiles) incorporating miniaturized electronic devices will pave the way toward a new generation of wearable devices and human-machine interfaces. Unfortunately, the development of e-textiles is subject to critical challenges, such as battery dependence, breathability, satisfactory washability, and compatibility with mass production techniques. This work describes a simple and cost-effective method to transform conventional garments and textiles into waterproof, breathable, and antibacterial e-textiles for self-powered human-machine interfacing. Combining embroidery with the spray-based deposition of fluoroalkylated organosilanes and highly networked nanoflakes, omniphobic triboelectric nanogenerators (R F -TENGs) can be incorporated into any fiber-based textile to power wearable devices using energy harvested from human motion. R F -TENGs are thin, flexible, breathable (air permeability 90.5 mm s −1 ), inexpensive to fabricate (<0.04$ cm −2 ), and capable of producing a high power density (600 µW cm −2 ). E-textiles based on R F -TENGs repel water, stains, and bacterial growth, and show excellent stability under mechanical deformations and remarkable washing durability under standard machine-washing tests. Moreover, e-textiles based on R F -TENGs are compatible with large-scale production processes and exhibit high sensitivity to touch, enabling the cost-effective manufacturing of wearable human-machine interfaces.

He received his B.Eng. degree from the Department of Production Engineering, Jadavpur University in 2014. He then joined the lab of Prof. Ramses Martinez in the School of Industrial Engineering, Purdue University, working on soft robotics and flexible biosensors, and in 2020, he obtained his Ph.D. His current research interests focus on modeling and development of soft robots, mechanical metamaterials, and flexible electronics.