2007 Volume 43 Issue 12 Pages 1075-1081
In this paper, a novel, unconstrained and wearable motion analysis system is described in which entire body posture and motion can be monitored using hetero-core optic fiber sensors with their significant performances in terms of the sensitivity, stability and the reproducibility due to the use of single-mode propagation scheme. The performance characteristics of the wearable sensor system are presented for the analysis of motion in the form of a sensing jacket, a wristband, and a gait system. The jacket has shown attractive performances with two sensors at the shoulder and a single sensor at the elbow. The use of only two hetero-core sensors at the shoulder effectively covered sufficient shoulder motion, such as abduction/adduction and flexion/extension, whereas the elbow sensor detected a loss variation of approximately 3dB for a flexion angle of 0-120°. The wristband is developed and tested to detect waving and beckoning motions of the wrist ranging from-30°to+30°and from -45° to+45°respectively, using only two sensors. The gait system also showed interesting performances with hetero-core sensors in sensing the motion of walking which consisted of knee flexing and the contact of the sole on a real-time basis.