Tunable origami metastructure based on liquid crystal for curvature sensing

Area of Science:

• Metamaterials and Advanced Structures
• Electromagnetics and RF Engineering
• Sensing Technologies

Background:

• Origami metastructures (OMS) offer unique tunable electromagnetic properties.
• Liquid crystals (LC) provide a versatile medium for dynamic control of material characteristics.
• Accurate curvature sensing is crucial for applications in robotics and structural health monitoring.

Purpose of the Study:

• To develop and characterize a liquid crystal tunable origami metastructure (LC-OMS) for curvature sensing.
• To investigate the electromagnetic performance of the LC-OMS across a broad frequency band.
• To evaluate the sensitivity and range of the LC-OMS for measuring curvature on cylindrical surfaces.

Main Methods:

• Design and fabrication of an origami metastructure incorporating K15 (5CB) liquid crystal.
• Electromagnetic wave (EMW) excitation within the 4–16 GHz band to analyze resonance frequency and absorption.
• Experimental measurement of frequency shift and absorption amplitude variations with applied curvature.

Main Results:

• The LC-OMS demonstrated tunable resonance across the 0.36–23 GHz band.
• A significant shift in resonance frequency (10.24 GHz to 10.144 GHz) and absorption amplitude (0.773 to 0.920) was observed.
• The sensor achieved a wide curvature detection range (0 to 0.327 mm^-1) with maximum sensitivity (S) of 0.918/mm^-1 and a Q-factor of 25.88.

Conclusions:

• The proposed LC-OMS is a highly sensitive and wide-range curvature sensor.
• Its tunable electromagnetic properties make it suitable for advanced sensing applications.
• Potential applications include bionic skin, smart robotics, and non-destructive testing.