PID controller is developed to stabilize the angular displacement of an inverted pendulum subjected to the relativistic gravitational effects near a black hole. A nonlinear mathematical model of the pendulum system is formulated,
incorporating position-dependent gravitational acceleration derived from the
Schwarzschild metric. The controller is designed to maintain system stability in the
presence of external disturbances and varying gravitational forces. Numerical
simulations are carried out in MATLAB, and the results demonstrate effective
stabilization performance both in nominal conditions and under perturbations.