Robust scanning controllers for Atomic Force Microscopes (AFM)

Program Code: 

A/Prof Hemanshu Pota (

Description of Work: 


The overall aim of this project is to increase the image scan rates of scanning AFM. Our control applications research laboratory has a scanning AFM. The work in this project involves both theoretical design of controllers and their experimental implementation. The AFM consists of a three degrees-of-freedom piezoelectric stack, a cantilever, and an optical arrangement to measure the cantilever tip-position. The image is the cantilever tip-position as the sample is moved in the x-y direction. Presently a PhD student is working to increase the x-y scan rate of this AFM. The proposed PhD is to include the cantilever dynamics and z-position loop in the design of the controller.

Description of Work:

  • Model the z-position loop using experimental data and theoretical analysis.
  • Obtain a suitable representation of the hysteresis nonlinearities and sensor noise.