Bioinspired Multifunctional Mechanoreception of Soft–Rigid Hybrid Actuator Fingers

Abstract

It is highly desired yet challenging to construct soft robots resembling the dexterous motor skills and powerful tactile sensations of human hands. Herein, a bioinspired design to create soft–rigid hybrid mechanoreceptive actuators (HMAs) and grippers is reported, imitating the musculoskeletal structure and embedded mechanoreception of human fingers, via careful ink preparation and a multimodality all‐3D‐printing technology. The HMAs consist of multiple rigid segments between joints, imitating phalanges, to mount flexible mechanoreceptive sensors in a flexible‐on‐rigid (FOR) design, yielding a bending‐insensitive unambiguous mechanoreception. The printed sensors exhibit a humanoid high sensitivity for low contact force and a wide low‐sensitivity linear detection range, combined with excellent long‐term stability and low hysteresis. As a result, the HMA gripper not only shows greatly enhanced output force due to the soft–rigid hybrid design, but also enables multifunctional mechanoreceptive sensing including contact identification, gentle grabbing, and the estimation of size, weight, and stiffness of the grasped objects. This integrated approach of constructing soft robots with mechanoreception can provide a pathway toward feedback control, integrative biomimetic functions, and human–machine interface for all soft devices.

Keywords

• bending-insensitive pressure sensing
• flexible-on-rigid
• multifunctional tactile sensing
• soft-rigid hybrid actuators