Adaptronics - state of the art and some future challenges

Smart structure technologies have gained increasing interest on the market during the last years. The demand for active systems refers predominantly to active vibration control, especially vibration reduction, but also excitation of vibrations, above all with regard to high frequency testing. In recent years many questions hindering a commercial exploitation of this technology have been resolved by now. New methods, procedures and tools for efficient dimensioning, realisation and evaluation of active structure systems are available. In addition, costs have been reduced, production procedures established and new methods for system reliability assessment were developed. One aspect of the present paper is to give an overview on the actual state of the art of some recent achievements. The next logical step of entering larger scale markets is facing obstacles on component level. Most smart technologies are still based on piezoelectric material systems, which are limited nowadays with respect to active vibration control relevant performance as well as reliability. This is due to the fact that within smart structures, piezoelectric components are exposed to mission profiles markedly differing from those in classical applications like fuel injection or precision positioning. Keywords in the context of performance are linearity of the material parameters in order to exploit the sensing and actuating properties in closed-loop control application to the maximum possible extent, as well as low hysteresis with positive effects on power electronics design. In the sense of high reliability, resistance against moisture, high electric bias field and handling during manufacturing are crucial topics. The second aim of the paper is to point out some actual demands for future research. Efficient use and distribution in future energy infrastructures largely depend on distributed control, metering and accounting functionalities. In such a Smart Grid essential components are distributed over the complete infrastructure, in particular parts of the infrastructure will be placed under possibly hostile end-user's control. Thus, the dependability of the Smart Grid depends on the security of every component deployed. Considering the large variety of known attacks on IT infrastructures proper protection mechanisms need to be considered already in the early design of Smart Grid architecture and their components. The notion of Trusted Computing established in the PC area can also be used in Smart Grids to establish trust among all involved stakeholders and to ensure the proper functioning of devices. This paper discusses relevant security requirements and introduces a vision of a security infrastructure for energy networks built on hardware trust anchors