A Multifunctional MWCNT strain sensor: sensing and damping
X. Li, A.K. Keshri, A. Agarwal, C. Levy
Florida International University, US
Keywords: multifunctional, two probe method, four probe method, free layer damping
Abstract:The goal of this work is to develop a new type of multi-functional mechanical strain sensor using multi-walled carbon nanotube (MWCNT) films. This new sensor is potentially to function as free layer damping treatment for passive vibration control and serve as strain sensor for active control at the same time. The new accomplishments of our work include: 1. The development of a new sensor resistance measurement scheme (Figure 1) and comparison of the resistance measured by both two point probe and four point probe method. Test results confirmed that the simple two point probe method is valid for resistance measurement but four point probe method can offer more accurate results. Figure 2 shows one comparison result. 2. The measurement of the damping effect of the MWCNT film sensor by free vibration method. It was found that the MWCNT composite sensor can provide some damping without adding excessive weight to the base structures. Damping was analyzed by bonding the MWCNT strain sensor to a cantilever beam and free vibration was measured. Our research indicated that the new multifunctional MWCNT film strain sensor can potentially function as damping treatment and strain sensor simultaneously for structural vibration control.