This thesis study aims at the problem of modeling and control of a two DOF robot arm usingrnPermanent magnet synchronous actuators. Permanent magnet synchronous actuator have been rnused in various industrial and domestic applications because of its advantages like simple rnstructure, large torque, long use. Trajectory tracking is a very difficult topic in robot arm control.rnThis is due the nonlinearities and input couplings present in the dynamics of the arm caused byrndynamics changes rapidly as the manipulator moves within its working range. Moreover, for arnrobot with gear transmissions, the gears have nonlinearities such as hysteresis, backlash, friction,rnand nonlinear elasticity. In industrial applications such complex systems are controlled using therntraditional PID controllers. However, a major drawback of the linear PID control is failed to track rnthe desired trajectory of the robot arm when the nonlinear system dynamics is dominant. In this rnthesis sliding mode controller is modeled to overcome the shortcomings of PID controller. ThernSMC is designed to control the joint trajectory of the robot. SMC adopts a switching function, andrnthese results in high-frequency oscillations (the so-called chattering) in the control signal. Tornreduce chattering, saturation function is used. rn The simulation is carried out using Level-2 MAT-LAB s-function and Simulink. PID controllerrnis designed for the comparison purpose with SMC without disturbance and parameter variationrnand the result shows Steady State error of SMC is 0.029% for joints one and 0.0098% for joint twornand increased to 15% and 24% respectively overshoot remain the same, rise time is decreased byrn0.16sec, and settling time is decreased by 0.4sec for both joints when PID controller is used. ThernSMC and PID with disturbance and parameter variation also tested and results show that thernperformances with disturbance and parameter variation are almost the same for SMC. The controlrninput voltage is increased by 0.03v and 0.02v for joint one and two respectively for SMC. Howeverrnthe amplitude of the control effort of PID controller with disturbance and parameter variation isrnmuch larger when compared to the control effort without disturbance and it is increased by 18vrnand 6.5v. Generally from the result it is possible to conclude that SMC has better performance,rnmore stable and robust than PID controller.