Vibration sensing and control in machinery and structures are essential to prevent premature failure and to reduce noise radiation levels Passive vibration absorbers and in particular viscoeiastic materials with high damping capabilities have been applied for this purpose. In recent applications, vibration control has been achieved using state-of-the-art 'smart' materials. A 'smart' material has been developed at Temple University, from a metallized ionomer membrane called Nafion. This electroded material can sense mechanical vibrations and generate a voltage response. somewhat like a piezoelectric material, which tself has already been utilized for Vibration damping applications. Electroded Nafion has a unique vibrational damping property. Damping with this material is achieved by dissipating the electrical energy generated as heat.This can be done using an external resistance or optimally by creating an internal mnductive path although with the latter t is dimcult to demonstrate true electrochemically based vibration damping. Work with internal conductive paths is underway but will not be reported here.Using the above, a prototype accelerometer cell has been developed which shows excellent linear characteristics and high sensitivity. It is found that the most critical element in both of the above applications is the sum of the internal and the contact resistances d the electroded Nafion hydrogen pressure call. Accordingly, a study of the resistance of these Nafion-based mils has been made and the results are included and discussed.

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