All-Fabric Tactile Sensors Based on Sandwich Structure Design with Tunable Responsiveness

Area of Science:

• Materials Science
• Sensor Technology
• Wearable Electronics

Background:

• Capacitive tactile sensors (TSs) are valuable for stress detection but face challenges in balancing sensitivity and linear range.
• Developing TSs with tunable responsiveness across broad pressure intervals is critical for practical applications.

Purpose of the Study:

• To engineer a textile-based capacitive tactile sensor with enhanced sensitivity, linearity, and a wide operating pressure range.
• To demonstrate the sensor's potential for smart garment applications and human-computer interfaces.

Main Methods:

• Fabrication of a sandwich-structured TS using Ag-coated Velcro and spacer fabric.
• Construction of multilayered frameworks by stacking TS units to modify performance characteristics.
• Characterization of sensor performance including sensitivity, pressure range, response speed, repeatability, and flexibility.

Main Results:

• A single-layer TS exhibited high sensitivity (0.036 kPa⁻¹) within 0.2-5 kPa.
• A four-layer TS achieved a broad sensing range (0.2-110 kPa) with a sensitivity of 0.002 kPa⁻¹.
• The sensor demonstrated excellent response speed (104 ms), repeatability (10,000 cycles), and flexibility.

Conclusions:

• The developed all-textile TS effectively balances sensitivity, sensing range, and linearity through multilayered construction.
• The facile manufacturing approach enables the creation of next-generation wearable electronic devices.
• Potential applications include human motion detection, pliable keyboards, and human-computer interfaces.