The paper presents an original geometrical and kinematic method for the study of geometry and determining positions of a MP-3R structure of the anthropomorphic robots. It presents shortly the MP-3R direct and inverse kinematics, the inverse kinematics being solved by an original exactly method. One presents shortly an original method to solve the robot inverse kinematics exemplified at the 3R-Robots (MP-3R). The system which must be solved has three equations and three independent parameters to determine. Constructive basis is represented by a robot with three degrees of freedom (a robot with three axes of rotation). If we study (analyze) an anthropomorphic robot with three axes of rotation (which represents the main movements, absolutely necessary), we already have a base system, on which we can then add other movements (secondary, additional). Calculations were arranged and in the matrix form. The most commonly used serial structures over the last 20 or 30 years are those of type 3R, 4R, 5R, 6R, having as constituents essential basic kinematic chain 3R, robot anthropomorphic (RRR), where main rotation around a vertical axis, causes the construction. It can thus passes from the study spatial movement, which is more difficult, to the study motion plane, basic movement, for all the robots and fillers serial movements of rotation. Moving flat, horizontal or vertical, shall be undertaken far more easily than the spatial integration with the convenience simple in the space of which it is part. We will exemplify the basic structure existing in a few serial platforms of rotation, these being the most generalized (more widespread) at the present time. In this work will be pursued and the direct and inverse kinematics of these mechanical systems. It can make the transition from 3R systems-level 2R and vice versa.