The paper presents an Open Architecture system for the MERO walking modular robot, which is a robot on 3×6 degrees of freedom, autonomous, being able to interact with the environment. Starting from purpose kinematics and kinetostatics analysis the mathematic model of the inverted kinematics is determined for controlling the main trajectory that defines legs’ support and weigh centre positions. Related to this there is presented an Open Architecture system for the MERO robot position control in Cartesian coordinates through real time processing of the Jacobean matrix obtained out of the forward kinematics using the Denevit-Hartenberg method and calculating the Jacobean inverted matrix for feedback. The obtained results prove a significant reduction of the execution time for the real time control of MERO robot’s position in Cartesian coordinates and increased flexibility.