The aim of this paper is to develop a Hardware-In-the-Loop (HIL) simulator of flexible-link mechanisms. The core of the simulator is a highly accurate FEM nonlinear dynamic model of planar mechanisms. The accuracy of the proposed simulator is proved by comparing the response of the virtual model with the response of the real mechanism by using the same real controller. Results are provided by the use of classical controllers real-time capability of the dynamic model is guaranteed by a symbolic manipulation of the equations that describe the mechanism, in order to avoid the numerical inversion of the large mass matrix of the system. This HIL simulator is a valuable tool for the tuning of closed-loop control strategies for this class of mechanisms, since it allows to reduce the safety risks and the time needed to fine tune the real-time controller parameters.
