This paper presents a finite-element analysis of vibration control in planar mechanisms consisting of flexible links provided with nearly collocated piezoceramic sensors and actuators. Euler-Bemoulli-theoty-based beam finite elements with p-convergence capabilities have been cast into a total Lagrangian formulation in order to represent large rotations of the links. A simple control strategy based on the placement of closed-loop poles has been applied. Numerical predictions of active vibration control in links undergoing geometrically non-linear deflections of the von Karman class are presented.