The paper presents a preliminary study needed to carry out a kinematic calibration procedure for a mini pointing device. The latter inherits its kinematics from a conventional five-bar linkage. A sensitivity analysis of all the geometric parameters involved in the kinematic model of the device is performed within the device workspace. A model is proposed by assuming a non overconstrained kinematics for the machine. Such assumption allows to consider a coupled rotational and translational motion of its moving platform, that is usually designed to have a fixed center of rotation. Results show how the model can be simplified without a significant reduction of its position accuracy, at least in a significant region of the manipulator workspace
