A Novel Accelerometer Mounting Method for Sensing Performance Improvement in Acoustic Measurements From the Knee.

Area of Science:

• Biomechanics
• Biomedical Engineering
• Wearable Technology

Background:

• Accelerometer-based knee sound analysis is vital for diagnosing joint conditions.
• Existing methods face limitations in accurately capturing high-frequency acoustic data.

Purpose of the Study:

• To introduce and validate a new accelerometer mounting method for improved knee sound measurement performance.
• To enhance accelerometer sensitivity in the 50 Hz-10 kHz frequency band.

Main Methods:

• A novel mounting approach combining thin double-sided adhesive tape and a 3D-printed backing prototype.
• Mechanical testing with an electrodynamic shaker to quantify performance improvements.
• Recording knee sounds from healthy subjects (n=10) with and without the backing force.

Main Results:

• A 13 dB increase in accelerometer sensing performance within the 1-10 kHz frequency band was observed.
• Statistically significant increases in spectral centroid and spectral roll-off frequencies (p < 0.01).
• High-frequency (1-10 kHz) root-mean-square (RMS) acceleration doubled with the backing force, while low-frequency remained unchanged.

Conclusions:

• The proposed mounting method effectively enhances accelerometer performance for knee sound measurements.
• The backing force significantly improves spectral characteristics and high-frequency acceleration capture.
• This technique shows potential for integration into wearable systems for advanced knee monitoring.