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An Inertial Measurement Unit Based Method to Estimate Hip and Knee Joint Kinematics in Team Sport Athletes on the Field
Published on: May 26, 2020
Kinematics of gait: new method for angle estimation based on accelerometers.
Milica D Djurić-Jovičić1, Nenad S Jovičić, Dejan B Popović
1School of Electrical Engineering, University of Belgrade, Bulevar kralja Aleksandra 73, Belgrade, Serbia. travis.jennings@ebioscience.com
Sensors (Basel, Switzerland)
|February 21, 2012
Summary
This study introduces a novel method using accelerometer arrays to accurately measure leg joint angles without complex calculations. This technique offers a drift-free, efficient approach for gait analysis in various conditions.
Area of Science:
- Biomechanics
- Biomedical Engineering
- Wearable Technology
Background:
- Accurate measurement of joint angles is crucial for gait analysis and understanding lower limb biomechanics.
- Traditional methods like optical motion capture are complex and expensive, while sensor-based methods often suffer from integration drift.
Purpose of the Study:
- To develop and validate a new method for estimating leg segment and joint angles using accelerometer arrays.
- To provide a drift-free and computationally efficient alternative for human movement analysis.
Main Methods:
- Utilized accelerometer arrays (two accelerometers per rod) attached to body segments.
- Determined absolute segment angles via band-pass filtering of accelerometer signal differences.
- Calculated joint angles by subtracting adjacent segment angles, avoiding double integration.
Main Results:
- The method successfully estimated leg joint angles during treadmill walking at speeds from 0.15 m/s to 2.0 m/s.
- Validation against flexible goniometers showed discrepancies below 6 degrees.
- High Pearson correlation coefficients were achieved: >0.97 for knee angle and >0.85 for ankle angle.
Conclusions:
- The accelerometer array method provides a reliable and accurate means for estimating lower limb joint angles.
- This technique offers a practical, drift-free solution for gait analysis and biomechanical studies.
- The method's efficiency and accuracy make it suitable for various applications in sports science and clinical rehabilitation.
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