Autonomous 3D Self-Sensing Hybrid Membrane Actuator for Interactive Communicating

The advancement of intelligent soft actuators is progressively emphasizing the incorporation of environmental sensing capability to actuation, thereby enhancing the adaptability and interactivity of artificial systems. In the current situation where the sensing and actuation functions of soft actuators are generally separated, this work proposes an autonomous three-dimensional (3D) noncontact sensory actuator (NSA), based on the coupling of ″dielectric polarization-electrothermal conversion-thermal actuation″ triple effects. Specifically, the NSA hybrid membrane is composed of multiple interpenetrating networks, including a boron nitride nanosheet (BNNS) dielectric network for electrostatic field sensing and polarization, a silver nanowires (AgNWs) percolation network for dielectric enhancement and electrothermal conversion, and thermally contracted shape memory fiber (SMF) and thermally expanded polydimethylsiloxane (PDMS) networks for directional actuation. Based on the principle of electrostatic field and dielectric polarization, the SMF/BNNS composite (SMF-BN) fibrous membrane can logically sense the noncontact 3D motion, static/dynamic state of external objects, and distinguish material categories. Subsequently, the output sensing potential facilitates the built-in AgNWs nanonetwork heater to trigger electrothermal actuation of NSA. Lastly, as a biomimetic tongue, the autonomous noncontact "sensing-decision-actuating" of NSA is verified by seamless energy conversion in the process of sensing "prey" approaching and capturing. The proposed sensory actuator would facilitate multimodal integration for future wearable and human-machine-environment interaction technologies.