INTRODUCTION

The approach used is this studie could be describe in two different phasis.

• In a first time we try to find a simple linear dynamical model using identification methods. For each subject it's possible to identifie the different coefficient of this second order model. The value of the model coefficients (and eventually their evolution), will give us important information about a possible pathological comportment.
• In a second time we try to retriew with this validate model a set of mechanical (or bio-mechanical) systems presenting the same dynamical comportment. This systems could be the basis of the development for a prothesis ensemble.

This paper describe essentially the results of the first part of this studie and the outline of the second part. So the plan of the presentation will be :

1. Description of the medical element and the experimental data.
2. Description of the identification method and of the validate model.
3. Transition between the identified model and a bio-mechanical system able to reproduce the ano-rectal inhibitory reflex.