Ext. Mech. Lett. 27, 52–58 (2019)

The idea of a soft wearable robot is appealing: imagine a glove that could grasp for you. Early prototypes using isotropic materials have given way to designs made from textiles, which are both light and intrinsically anisotropic — thus dispensing with the complex architectures. But cutting and sewing textiles takes time, and introduces weaknesses into any would-be robot. Now, Fionnuala Connolly and co-workers have come up with a bending actuator that can be fabricated quickly without seams, and optimized to perform a given task.

The team used a film to make their textiles impenetrable to air, and found that it could also bond to itself with the help of a heat press — offering a no-sew, time-saving solution. They then formulated a method based on strain energy minimization to predict the deformation of the actuator and optimize its parameters. Their test case — a glove designed to aid grasping — demonstrated the power of both fabrication and optimization processes by successfully picking up a glass jar.