Sensor Cell Network for Pressure, Temperature and Position Detection on Wheelchair Users.

Area of Science:

• Biomedical Engineering
• Optical Sensing Technology
• Materials Science

Background:

• Pressure ulcers are a significant concern for wheelchair users, often caused by prolonged, uneven pressure distribution.
• Accurate monitoring of pressure and temperature is crucial for timely intervention and prevention.
• Existing monitoring systems may lack the precision or adaptability required for dynamic wheelchair use.

Purpose of the Study:

• To develop and validate an optical sensing network for real-time monitoring of pressure and temperature in wheelchairs.
• To assess the system's capability in preventing pressure ulcers by analyzing pressure distribution.
• To evaluate the system's accuracy in identifying user positions and movements within the wheelchair.

Main Methods:

• Construction of a sensing network using six optical fiber Bragg grating (FBG)-based sensor cells.
• Each sensor cell incorporates two FBGs: one for pressure (FBG_P) and one for temperature (FBG_T), integrated with a polylactic acid (PLA) base.
• Experimental characterization of sensor sensitivity to pressure and temperature, followed by in-situ testing within a wheelchair.

Main Results:

• The sensor cells demonstrated average pressure sensitivities of 81 ± 5 pm/kPa (FBG_P) and -5.0 ± 0.4 pm/kPa (FBG_T).
• Average temperature sensitivities were recorded as 25 ± 1 pm/°C (FBG_P) and 47.7 ± 0.7 pm/°C (FBG_T).
• The network successfully monitored pressure and temperature in real-time and identified user position changes during experimental tests.

Conclusions:

• The proposed optical sensing network effectively monitors pressure and temperature in wheelchairs.
• The system shows promise for preventing pressure ulcers and enhancing user safety through positional awareness.
• FBG-based sensors offer a viable solution for intelligent wheelchair monitoring systems.