ABSTRACT Robotic is an electromechanical system, help improve production accuracy, and reduces time and increase production. In this project a study of 3D robotic ARM design, simulation concepts and theories for the painting of cars that deals with the design, construction, operation, and application of robots is conducted. The simulation covers different parameters to evaluate the design. Moreover simulation environment help to test these parameters cost effectiveness of building robots and selecting optimal component, dimensions and Accuracy is used. COMSOL application was selected as a simulation design and modeling program, that give the ability to fabricate 3D Objects and simulate the movement, the matlab program was used to control the object movement through commands stored in M File linked to the graphical user interface. The 3D robotic arm was tested in MATLAB environment. The test has been applied for car painting in its three parts front, middle and end of the car.