Algorithms for control of scanning probe microscopes using quartz tuning forks

In the last years tuning forks have emerged as detectors for precise control of scanning probe microscopes. It has been shown that such sensors can be very effectively implemented. The firm Elatec.d.o.o has already cooperated in developement of controllers for scanning probe microscopes using tuning forks, but the analogue technique has been used in the controlling process. The purpose of this project is to improve the existing solutions and introduce algorithms for digital control of the tuning fork. This will enable improved precision, faster response, and will reduce the cost of production. In the beginning stage the surface will be modelled using cycles in Lie geometry, which will enable a compact algebraic description. The computation of a step along the surface between cycles will thus be reduced to a simple calculation. In the second stage, the obtained algorithms will be extended to more general surfaces using a detailed analysis or the experimentally observed parameters of the tuning fork.