Material Extrusion-Enabled Soft Multimodal Pressure Sensors With Fabrication-Embedded Stretch-Induced Strain...

Area of Science:

• Materials Science
• Robotics
• Sensor Technology

Background:

• Stretchable pressure sensors face challenges in cost-effective fabrication, strain insensitivity, and integration into soft systems.
• Existing methods often struggle to balance performance, stretchability, and manufacturability.

Purpose of the Study:

• To develop stretchable pressure sensors with multimodal sensing capabilities using a combination of electrospinning and material extrusion techniques.
• To achieve high strain insensitivity and seamless integration into soft architectures for advanced applications.

Main Methods:

• Fabrication of a sensing layer using electrospun poly(vinylidene fluoride)/thermoplastic polyurethane composite microfibers.
• Integration with liquid-based material extrusion (l-MEX) printed silver electrodes and a 3D serpentine architecture.
• Utilizing both capacitive and piezoelectric sensing modes for multimodal detection.

Main Results:

• The sensor demonstrated 97.6% strain insensitivity in capacitive mode (up to 30% strain) and a minimum detectable pressure of 0.04 kPa.
• In piezoelectric mode, the sensor achieved a sensitivity of 16.5 mV/kPa with 85.4% strain insensitivity at 10% strain.
• A stretchable capacitive sensing matrix enabled uniform pressure mapping, and integration into a soft gripper showed real-time piezoelectric responses.

Conclusions:

• A scalable and automatable manufacturing route for soft functional materials in stretchable electronics was established.
• The developed sensors offer a promising solution for integrating advanced sensing capabilities into soft robotic systems.
• The multimodal sensing approach enhances the versatility and reliability of stretchable pressure sensors.