Cycle-to-cycle response of ionic polymer-metal composite materials subject to pulsing flow-induced stimulus

Ionic polymer-metal composites (IPMCs) are considered as new intelligent materials that have found their presence into many challenging applications such as flow sensing and actuating. Although several intrinsic features of IPMC materials related to flow measurements have been identified, not much information is available regarding the cycle-to-cycle response of IPMC materials subject to pulsing flow-induced stimulus. This paper presents an investigation of using the IPMC material as a sensing element for measuring the cycle-to-cycle characteristics of pulsing flow. Test data have been collected from fluid flow experiments whereas a number of key characteristic parameters are used to quantify the cyclic variation of the sensor response signal. The results illustrate that the sensor´s response and the form of oscillation are consistent with the fluid pulses. While there are distinct differences of the IPMC response signal corresponding to the leading and trailing edges of the driving logic pulse, the cycle-to-cycle variation is not significant. An on-going effort is to correlate the signal profile of the IPMC´s response with the rheological properties of fluid. This could add potential functionality of IPMC materials as sensing element for characterizing different fluid flow conditions.