An Ankle Joint Flexion and Extension Movement-Monitoring Device Based on Pressure Sensors

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Sensor Systems

Background:

• Ankle flexion and extension are crucial for post-surgery and long-term bedridden patient rehabilitation.
• Deep vein thromboembolism risk is reduced by guided ankle movements.
• Existing rehabilitation devices primarily assist movement, lacking effective monitoring capabilities.

Purpose of the Study:

• To design and validate a pressure sensor-based device for monitoring ankle joint flexion and extension movements.
• To assess the accuracy and effectiveness of the developed monitoring system.

Main Methods:

• Developed a monitoring device integrating an STM32 microcontroller, pressure sensor, HX711 A/D converter, and ESP8266 WiFi module.
• Utilized experimental setups to verify the system's accuracy in measuring force and movement counts.
• Collected data on force values and effective ankle movements.

Main Results:

• The system accurately measured the force of ankle flexion and extension movements.
• Experimental validation showed a maximum average error of 0.068 N and a maximum average relative error of 1.7%.
• The device demonstrated high accuracy with a maximum mean-squared error of 0.00464 N.

Conclusions:

• The developed pressure sensor-based device accurately monitors ankle joint flexion and extension movements.
• This technology can enhance patient self-monitoring and adherence to active ankle pump exercises.
• The system offers a valuable tool for improving rehabilitation outcomes and preventing complications like deep vein thromboembolism.