Ambulatory Measurement and Analysis of the Lower Limb 3D Posture Using Wearable Sensor System
DOI: 10.1109/ICMA.2009.5245982 Conference: Mechatronics and Automation, 2009. ICMA 2009. International Conference on
An original approach for ambulatory measurement and analysis of lower limb 3D gait posture was presented, and a wearable sensor system was developed according to the approach. To explicate the lower limb posture, thigh orientation angles were calculated based on a virtual sensor at the hip joint and double analog inertial sensors (MAG3) on the thigh; Knee joint angle in sagittal plane was calculated with combination of angular accelerations and angular velocities measured by two MAG3 on the thigh and shank on the basis of the virtual-sensor based algorithm. The developed wearable sensor system was evaluated on the lower limb. Without integration of angular acceleration or angular velocity for the thigh orientation angles and the knee joint angle, the calculated result was not distorted by offset and drift. Using virtual sensors at the hip joint and the knee joint were more simple, practical and effective than fixing physical sensors at these joints. Compared with the result from the reference system, the measured result with the developed wearable sensor system was feasible to do gait analysis for the patients in the daily life, and the method can also be used in other conditions such as measuring rigid segment posture with less sensors and high degree of accuracy.
Available from: Thomas Schauer
- "Apparently, these techniques can lead to very poor results unless a tight mechanical setup is used to restrict the motion. A tempting alternative is to mount the sensors with a predefined orientation towards the segment or joint, as in  and . But besides the fact that this is hard to realize for some applications, e.g. "
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Control Applications (CCA), 2012 IEEE International Conference on; 01/2012
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Electronics, Robotics and Automotive Mechanics Conference (CERMA), 2012 IEEE Ninth; 01/2012
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