This work aims to define a method for estimating the position and the orientation of the human limbs. Accurately tracking the movements of the human body is a crucial operation for what concerns several applications, like, for example, the remote motor rehabilitation or the creation of a persons' virtual model in a video game, to mention just a few. In particular, an inertial measurement unit (IMU) sensor network is exploited to measure the acceleration and the angular velocity of the upper limb parts, which are combined, along with a kinematic model of the arm, in a sensor fusion algorithm to estimate the orientation of the limb up to the wrist.