Force estimation in a piezoelectric cantilever using the inverse-dynamics-based UIO technique

This paper presents the estimation of the force applied by a piezocantilever dedicated to micro-manipulation/microassembly. Relative to previous works, the presented method avoids the reliance on the force dynamics on the characteristics of the micro-objects. Furthermore, the estimation is a closed-loop kind technique so that convergency can be ensured efficiently. To perform these, we consider the force at the tip of a piezocantilever as an unknown input and we use an unknown input observation technique. We especially use the inverse-dynamics-based UIO technique because it is well suited for a piezo-cantilever model. The experiments show that the performances of the observer are convenient for micromanipulation/microassembly tasks.