A Novel Sensor Prototype with Enhanced and Adaptive Sensitivity Based on Negative Stiffness Mechanism.

Area of Science:

• Geotechnical Engineering
• Geophysics
• Sensor Technology

Background:

• Interfacial landslides in loess-mudstone/soil-rock zones pose significant hazards.
• Early warning systems require sensors with high sensitivity to weak, low-frequency vibrations.

Purpose of the Study:

• To develop a novel monitoring sensor prototype with enhanced and adaptive sensitivity.
• To address the need for sensitive detection of vibrations preceding interfacial landslides.

Main Methods:

• Design and fabrication of a Micro-Electro-Mechanical Systems (MEMS) sensor prototype.
• Utilizing variable capacitances and a negative stiffness mechanism driven by electric field forces.
• Implementing feedback control via an embedded microcontroller for adaptive amplification.
• Post-signal processing and preliminary testing, including mimicking a sand interfacial slide.

Main Results:

• The developed sensor prototype exhibits adaptive amplification characteristics.
• The sensor demonstrates high sensitivity to weak and low-frequency inputs.
• The sensor shows low sensitivity to high-frequency inputs, improving signal-to-noise ratio.
• Preliminary tests confirmed the sensor's performance in detecting interfacial slide vibrations.

Conclusions:

• The novel MEMS sensor prototype effectively provides enhanced and adaptive sensitivity for interfacial landslide monitoring.
• The sensor's design is suitable for early warning systems of soil-rock interfacial landslides.
• The adaptive amplification mechanism is key to detecting subtle vibrations indicative of impending landslides.