A Developed Jerk Sensor for Seismic Vibration Measurements: Modeling, Simulation and Experimental Verification

Area of Science:

• Mechanical Engineering
• Structural Health Monitoring
• Seismology

Background:

• Acceleration sensors are vital for assessing structural damage during dynamic events like earthquakes.
• Calculating jerk (rate of change of acceleration) is crucial for understanding seismic wave effects on structures.
• Traditional jerk calculation via acceleration differentiation is error-prone, especially for low-frequency, small-amplitude signals, limiting real-time applications.

Purpose of the Study:

• To develop a direct jerk sensor for accurate measurement of seismic vibrations.
• To optimize the design of a metal cantilever-based jerk sensor for enhanced sensitivity and measurement range.
• To validate the sensor's performance for structural health monitoring applications.

Main Methods:

• Designed and optimized an austenitic stainless steel cantilever (L-35 model: 35 × 20 × 0.5 mm³, 139 Hz natural frequency).
• Integrated the cantilever with a gyroscope for direct jerk measurement.
• Conducted analytical and finite element (FE) analyses for design optimization.
• Performed theoretical and experimental validation of the sensor's performance.

Main Results:

• The L-35 jerk sensor demonstrated a constant sensitivity of 0.05 (deg/s)/(G/s) with ±2% error within the 0.1–40 Hz seismic frequency range.
• The sensor accurately measured jerk for amplitudes between 0.1 and 2 (G).
• Calibration curves showed high linearity with correlation factors of 0.99 (theoretical) and 0.98 (experimental).

Conclusions:

• The developed direct jerk sensor offers significantly enhanced sensitivity compared to existing methods.
• The sensor is suitable for precise seismic vibration monitoring and structural health assessment.
• This technology overcomes limitations of acceleration differentiation for real-time jerk measurement.