Reconstructed Phase Spaces of Intrinsic Mode Functions. Application to Postural Stability Analysis

Hichem Snoussi (1) , Hassan Amoud (1) , Michel Doussot (1) , David Hewson (1) , Jacques Duchene (1)

1 LM2S - Laboratoire Modélisation et Sûreté des Systèmes

In this contribution, we propose an efficient nonlinear analysis method characterizing postural steadiness. The analyzed signal is the displacement of the centre of pressure (COP) collected from a force plate used for measuring postural sway. The proposed method consists of analyzing the nonlinear dynamics of the intrinsic mode functions (IMF) of the COP signal. The nonlinear properties are assessed through the reconstructed phase spaces of the different IMFs. This study shows some specific geometries of the attractors of some intrinsic modes. Moreover, the volume spanned by the geometric attractors in the reconstructed phase space represents an efficient indicator of the postural stability of the subject. Experiments results corroborate the effectiveness of the method to blindly discriminate young subjects, elderly subjects and subjects presenting a risk of falling.

Domaines: Ingénierie biomédicale

Hichem Snoussi, Hassan Amoud, Michel Doussot, David Hewson, Jacques Duchene. Reconstructed Phase Spaces of Intrinsic Mode Functions. Application to Postural Stability Analysis. Conference Proceedings. Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Aug 2006, New York, United States. pp.4584-4589, ⟨10.1109/IEMBS.2006.259922⟩. ⟨hal-02359047⟩