In this work an model inverted pendulum with a single degree of freedom controlled by proportional, integral and differential (PID) controller is used in order to simulate the vibration of center of pressure (COP) of a human body in forward-backward direction during still standing. Numerical experiments using data of typical adult male and different disturbance signals revealed that identified model parameters set coincide with the set reported in the literature which is able to reproduce realistic COP signals and did not depend on the particular sample of a disturbance signal. In this work parameter identification of the model for a particular person is based on an optimal control technique.