A new approach of methodology in the field of modeling and simulation of mechatronics designs of high complexity, formed by a mobile platform and a manipulator arm is presented, this methodology considers the systematic analysis of an IEDD unit [1] (improvised explosive device disposal) divided into 7 stages in order to increase the accuracy of validation of whole system, this mechatronic unit is a Nonholonomic Unmanned wheeled mobile manipulator, MU-NHWMM, formed by a Differential Traction and a manipulator arm with 4 degrees of freedom mounted on wheeled mobile platform, hence the contribution of this work is a novel methodology based on a practice proposal of philosophy of mechatronics design, which establishes the suitable kinematics to coupled wheeled mobile manipulator, where the motion equations and kinematics transformations are the base of the specific stages in order to obtain the dynamic of coupled system, validating the behavior and the trajectories tracking, in order to achieve the complex tasks of approaching to work area the suitable handling of explosive device and transportation to deactivation area,; such that the errors in the model can be detected and later confined by proposed control.