(223d) Ag-CNT-Silicone Based Piezoresistive Tactile Sensor with< 200 ?m Spatial Resolution for Large Area Artificial 3D-Curved Skin Deployment and Posture Stability Applications

The soft robotics or next generation robotics, with highly compliant materials is unraveling the limitations in mimicking the human sensing abilities. Tactility and haptic sensing is very substantial in Human-Robot Interaction (HRI). Here we propose a novel piezoresistive sensor for motion detection and tactile/haptic sensing applications. The synthesis of 300 microns in diameter, highly flexible wire with piezoresistive sensing of 5% to 400% strain. Silver nanoparticles AgNPs were attached to the surface of MWCNT by repetitive chemical reduction technique. Ag-MWCNT-Silicone wires were prepared by the addition of known concentrations of Ag-MWCNT in 20 mL toluene and was sonicated for 1 hr. Homogeneous dispersion of MWCNT in silicone was induced by mixing at high temperature (70°C- 90°C) and sonication. At high temperature (80°C), relatively less viscous solution of Ag-MWCNT-Silicone was micro-molded in to the polytetrafluoroethylene (PTEE) 0.3 mm diameter tubes by high pressure syringe pump and was cured for 20 min during centrifuging at 12000 RPM. At 12000 RPM the conductive filler arranged itself on the surface of the as-synthesized wires making it highly responsive to the applied strains. The resultant wires were insulated by ≤ 50-micron silicone layer further it is analyzed for piezoresistive properties. These wires were used to form wide range of sensing devices from large area deployment tactile/haptic sensing device to human body motion detection type sensor.