Visual control of a microrobot operating under a microscope

In this paper the vision-based control of a microrobot operating under a light microscope is presented. For high accuracy manipulation the parameters describing the relationship between the reference frame and the frame attached to the robot must be continuously and accurately updated These parameters are unknown a priori and are not directly measurable, but can be deduced by observing the scene change during the motion. The relative positioning accuracy is about 100 nm and trajectories can be precisely followed in 3 degrees of freedom. Experimental results are presented.