Smart Triggering of the Barometer in a Fall Detector Using a Semi-Permeable Membrane

Area of Science:

• Wearable technology
• Biomedical engineering
• Sensor technology

Background:

• Barometers in wearable fall detectors improve accuracy by detecting altitude changes during falls.
• Barometer power consumption is a major limitation, reducing battery life in these devices.

Purpose of the Study:

• To propose and evaluate a novel triggering method to reduce barometer power consumption in wearable fall detectors.
• To extend the battery life of wearable fall detectors while maintaining high detection performance.

Main Methods:

• A hermetically sealed enclosure with a semi-permeable membrane (SPM) was used to delay pressure equalization.
• This allowed the barometer to operate in a low-power mode, waking only to capture pressure changes during falls.
• Differential Moving Average Filter (DMAF) and Kalman Filter (KF) were used for signal processing.

Main Results:

• The proposed method achieved long battery life: 447 days (DMAF) and 444 days (KF).
• High detection accuracy was maintained: sensitivity of ~91.8-91.9% and specificity of ~95.2-95.5%.
• Low false alarm rates were observed: 0.035 alarms/hour (DMAF) and 0.064 alarms/hour (KF).

Conclusions:

• The proposed triggering method effectively reduces barometer power consumption in wearable fall detectors.
• This approach significantly prolongs battery life without sacrificing fall detection accuracy or increasing false alarms.
• The technology offers a promising solution for long-term, reliable fall monitoring in wearable devices.