Modeling and control of a new actuation mechanism for Interfacial Force Microscopy

In this paper, a new model for a capacitance- based force sensor used in interfacial force microscopy (IFM) is proposed. This model considers both rotation and bending of the torsion bars of a teeter-totter mechanism. A new actuation method is introduced which greatly reduces the stress and strain of the torsion bars. This results in increased sensitivity of the sensor. A dynamic output feedback controller for this actuation scheme is utilized in which the only measurement required is the position of the sensor. Simulation results are presented that confirm the analytical results.