Abstract:
Acoustic radiation or reflection from a surface is a function of the surface impedance, which can be controlled using smart sensor--actuator systems. In this study a smart surface coating is developed using a 1-3 composite actuator with embedded accelerometers. This active coating can be electronically varied to present a wide range of impedance conditions. A feature of this system is its low fabrication cost: It is formed by an injection molding process developed by Material Systems, Inc. (MSI) which allows the accelerometer and actuator to be co-formed in one fabrication step. This paper describes the design, performance, and control issues related to smart surfaces formed using this process. Applications in underwater acoustics and structural vibration control are considered.