A Flexible Tactile Sensor Based on Porous Graphene Sponge for Tiny Force Measurement

Flexible tactile sensors have been utilized for epidermal pressure sensing, motion detecting, and healthcare monitoring in robotic and biomedical applications. This paper develops a novel piezoresistive flexible tactile sensor based on porous graphene sponges. The structural design, working principle, and fabrication method of the tactile sensor are presented. The developed tactile sensor has 3 × 3 sensing units and has a spatial resolution of 3.5 mm. Then, experimental setup and characterization of this tactile sensor are conducted. Results indicated that the developed flexible tactile sensor has good linearity and features two sensitivities of 2.08 V/N and 0.68 V/N. The high sensitivity can be used for tiny force detection. Human body wearing experiments demonstrated that this sensor can be used for distributed force sensing when the hand stretches and clenches. Thus the developed tactile sensor may have great potential in the applications of intelligent robotics and healthcare monitoring.