The rotary inverted pendulum is one of the fundamental problems existing in the field of Control Engineering. This mechanism possesses a high degree of non-linearity and hence, it is a highly unstable system. The basic control intention of the rotary inverted pendulum is to sustain the unstable equilibrium position. Since the rotary inverted pendulum is an under-actuated mechanism, the control can be done regulating the force applied to the actuator. In this paper, the mathematical model of the mechanism is presented. From the mathematical model, the fuzzy logic controller scheme was developed. A comparison of the performance of fuzzy logic controller and PID controller was presented. The performance of the proposed control algorithms was e...