Control of Atomic Force Microscopes


Atomic Force Microscope (AFM) is an instrument designed for scanning surface topographies at nanometric scales. In an AFM, a sharp tip supported on a micro-mechanical cantilever scans the topography of a surface by moving a probe over the surface of the sample and monitoring the interaction between the surface and the probe. Nanopositioning is a vital element of a AFM as it controls the interaction distance between the probe and the sample and creates the raster scan pattern in order to create an image of the surface. Developing high-precision and high-bandwidth nano-positioning instruments can improve research areas that rely on AFMs. The data-driven control method uses the frequency response method and cancels the high-frequency dynamics by convex optimisation. If  the dynamics of the system change through time, it triggers an identification process of the system dynamics while the AFM is scanning the sample. This re-identification is then used to design a controller based on the latest frequency response of the system. The fast nature of this controller design process makes it possible to account for the changes and redesign the controller during the imaging process. 


This project is carried out in collaboration with Laboratory for Bio- and Nano- Instrumentation (LBNI) of EPFL. 


  1. Innosuisse


Large‐Range HS‐AFM Imaging of DNA Self‐Assembly through In Situ Data‐Driven Control, AP Nievergelt, C Kammer, C Brillard, E Kurisinkal, MMC Bastings, A. Karimi, GE Fantner, Small Methods 3 (7), 2019.

Data-Driven Controller Design for Atomic-Force Microscopy, CM Kammer, AP Nievergelt, G Fantner, A Karimi, Proceedings of the 20th IFAC World Congress, 2017.