Printing of Tactile Sensors Upon the Surface of Pneumatic Soft Gripper by Direct Writing and Electrospraying to Enable Intelligent Grasping

Soft grippers with sensory‐integration mimicking humanoid hands, capable of grabbing various kinds of objects in a safe and easy manner, have numerous potential applications in advanced areas. However, precise sensing capabilities of the soft grippers for external stimuli are still nascent and fabrication of integrating sensory receptors remains a challenge. Herein, multiple tactile (pressure, temperature, and humidity) sensors are fabricated on the surface of pneumatic soft fingers by printing technologies including direct writing and electrospraying to simultaneously detect external stimuli while grasping. Composites composed of graphene nano‐platelets (GNPs)/multi‐walled carbon nanotube (MWCNT)/polyethylene oxide (PEO), reduced graphene oxide (rGO), and graphene oxide (GO) are selected as sensitive materials for pressure, temperature, and humidity sensor, respectively. The fingers are able to bend with an angle of 75^° and output force of 0.133 N under air pressure of 12 kPa. The printed tactile sensors exhibit good sensing performance. The application of grasping a lemon, a cooked egg, and a plum demonstrates that the pneumatic soft gripper owns the capability of accurately detecting tactile changes during grasping different objects. Thus, such integration methods by direct writing and electrospraying will open a facile technical platform for constructing the soft grippers with tactile sensors.