AFM tip on-line positioning by using the landmark in nano-manipulation

AFM has been proved to be a powerful nano-manipulation tool taking advantage of its ultra high resolution and precision. However the large spatial uncertainties associated with AFM tip positioning dual to the PZT nonlinearity and thermal drift are still challenging problems, which hinders its wide application especially in building complex structures In this paper, a probabilistic approach combined with the Kalman filter based localization algorithm is proposed to improve the accuracy of the tip positioning in the task space coordinate frame. A motion model based on the Prandtl-Ishlinskii (PI) model is established, the distribution of model error is statistically obtained through the experimental calibration process. In addition, to further reduce the tip position uncertainties, an environment measurement models is developed through sensing the landmark intermittently with local scanning method during manipulation. Both the simulations results and experimental results are presented to demonstrate the validity of the proposed method.