Analysis of Acceleration Signals using Wavelet Transform
07 February 2018 (online)
In this study, we attempted to discriminate the acceleration signal for horizontal level and stairway walking using wavelet-based fractal analysis method. The acceleration signal was measured close to the center of gravity of the body, while the subjects walked continuously in the corridor and up and down the stairs. We used the wavelet-based fractal analysis method to discriminate walking pattern. The parameter H which is related directly to the fractal dimension was estimated by the wavelet coefficient and was changed into low value during walking upstairs. By manually setting the threshold level for individual, it was possible to discriminate walking upstairs from the other walking type. However, the common feature among subjects was not shown between level walking and walking downstairs.
- 1 Bouten CV, Koekkoek KTM, Verduin M, Kodde R, Janssen JD. A triaxial accelerometer and portable data processing unit for the assessment of daily physical activity. IEEE Trans Biomed Eng 1997; 44: 136-47.
- 2 Makikawa M, Iizumi H. Development of an ambulatory physical activity memory device and its application for the categorization of actions in daily life. Medinfo 95 Proc. 1995: 747-50.
- 3 Fahrenberg J, Foerster F, Smeja M, Muller W. Assessment of posture and motion by multichannel piezoresistive accelerometer recordings. Psychophysiology 1997; 34: 607-12.
- 4 Aminian K, Robert P, Jequier E, Schutz Y. Estimation of speed and incline of walking using neural network. IEEE Trans Instrum Meas 1995; 44: 743-6.
- 5 Tamura T, Sekine M, Ogawa M, Togawa T, Fukii Y. Classification of acceleration waveforms during walking by wavelet transform. Method Inform. Med 1997; 36: 356-9.
- 6 Wornell WG, Oppenheim AV. Estimation of fractal signals from noisy measurement using wavelets. IEEE Trans Signal Processing 1992; 40: 611-23.
- 7 Akay M, Mulder EJH. Effects of maternal alcohol intake on fractal properties in human fetal breathing dynamics. IEEE Trans Biomed Eng 1998; 45: 1097-103.
- 8 Sekine M, Tamura T, Akay M, Togawa T, Fukui Y. Discrimination of walking patterns using wavelet-based fractal analysis (submitted).