A mathematical model is presented to determine the spatial displacement of an endeffector attached to the human upper limb kinematic chain. The proposed method in-volves the
successive application of the homogenous rotation matrices associated with each element
movement to determine the general transfer matrix or the so-called homoge-neous transformations
matrix. This method is proven to be an error free method for esti-mating the position and orientation
of an end-effector attached to a kinematic chain. The methodology presented in this paper combines
a well know mathematical technique used in engineering (in the development of space robots) and
the anatomical features of the human upper limb to estimate not only the end-effector 3D position
but also the limb pos-es during a particular displacement.