80 S. Davaria and P. A. Tarazaga signal’s frequency component that matched the AHC’s fundamental frequency. Furthermore, it could amplify or compress the detected signal component at a compressive rate of about one-third. In the next step, the periodic signal was applied to the array and its amplitude was varied. The input-output curves showed that the targeted compressive rate (about one-third) was achieved and the output of the system was amplified or compressed depending on the input level. Therefore, the array’s AHCs showed desired behavior near the fundamental frequencies of the beams. The results also displayed that the AHC could mimic the frequency selectivity of the cochlea. Furthermore, it was observed that even for the highest input amplitude studied in this work where all the AHCs in the system compressed the response, the output at each fundamental frequency was detectable. In summary, this study showed the compatibility of the control law developed for single AHCs with AHC arrays that are excited by complex stimuli. Therefore, the active AHCs can be used as suitable candidates in an array format for sensor development or cochlear implants, as they can mimic the frequency selectivity and compressive nonlinearity of the cochlea. Lastly, the numerical study presented in this chapter provided a framework for future experimental analysis of AHC arrays. Acknowledgments The authors would like to acknowledge the generous support from the National Science Foundation (NSF) (Grant No.1604360) that provided the funding for this project. Dr. Pablo A. Tarazaga would also like to acknowledge the John R. Jones III Faculty Fellowship. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. References 1. Dallos, P.: The active cochlea. J. 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