Sharif Digital Repository

Nowadays, the atomic force microscopy (AFM) has become a useful laboratory tool with variety of applications. In the traditional imaging technique, usually the amplitude or frequency of AFM tip oscillations is set at a desired value using a feedback control system which is a relatively slow process. In the current research, we propose an estimation approach which uses an adaptive fading extended Kalman filter (augmented with forgetting factor) as a system observer and couples with the system dynamics to determine the sample topography. As a result, in addition to state variables of system dynamic, the sample height as an unknown parameter is estimated with high accuracy in a relatively short...