Bioinspired Cilia Sensors with Graphene Sensing Elements Fabricated Using 3D Printing and Casting

Area of Science:

• Materials Science
• Biomimetics
• Sensor Technology

Background:

• Nature-inspired sensor designs offer optimal performance due to evolutionary refinement.
• Conventional fabrication methods struggle to replicate complex 3D biomimetic sensor structures.

Purpose of the Study:

• To introduce a simplified fabrication workflow for flexible sensors with intricate, bioinspired designs.
• To demonstrate the feasibility of creating high-performance flexible sensors using a novel processing paradigm.

Main Methods:

• Fabrication involved 3D printing a metallic mold with microfeatures.
• Polydimethylsiloxane (PDMS) was cast in the mold, followed by drop-casting piezoresistive graphene nanoplatelets.
• A flow sensor inspired by natural cilia was constructed using this method.

Main Results:

• A graphene-on-PDMS strain gauge achieved a high gauge factor of 37.
• The fabricated cilia-inspired flow sensor demonstrated sensitivity to tactile stimuli (detection threshold 12 µm).
• The sensor also showed sensitivity to water flow stimuli (detection threshold 58 mm/s).

Conclusions:

• The proposed 3D printing and casting workflow enables simplified fabrication of complex, flexible, bioinspired sensors.
• This method is effective for developing sensitive flow sensors with applications in various fields.
• The study highlights the potential of biomimetic designs and advanced materials for next-generation sensing technologies.