Animals can measure acoustic flow; with the help of MEMS, we can too

Abstract

Animals measure acoustic flow by using thin hairs. These hairs are essentially mechanical structures that are driven by viscous forces. Manufacturing thin hair-like structures is challenging, but we can think of other mechanical structures driven by viscous forces that can be manufactured more easily. Here, we discuss how MEMS technology can be used to fabricate a thin porous membrane and electrodes for measuring acoustic flow. We discuss the design trade-offs between performance, manufacturability, and product integration. For example, from a performance perspective, it is desirable that the membrane be as thin as possible, but from a manufacturing perspective, it is easier to make it thicker. We present preliminary results on early prototypes and discuss avenues to create a MEMS acoustic flow sensor that could be found in your smartphone within the next few years. Animals measure acoustic flow by using thin hairs. These hairs are essentially mechanical structures that are driven by viscous forces. Manufacturing thin hair-like structures is challenging, but we can think of other mechanical structures driven by viscous forces that can be manufactured more easily. Here, we discuss how MEMS technology can be used to fabricate a thin porous membrane and electrodes for measuring acoustic flow. We discuss the design trade-offs between performance, manufacturability, and product integration. For example, from a performance perspective, it is desirable that the membrane be as thin as possible, but from a manufacturing perspective, it is easier to make it thicker. We present preliminary results on early prototypes and discuss avenues to create a MEMS acoustic flow sensor that could be found in your smartphone within the next few years.