In this paper，a possible vibration model is conjectured according to the vibration

characteristics of Wilberforce pendulum. Based on this model，the dynamic differential equations of

Wilberforce pendulum are written out. Then the normal frequency and the analytical solution of the

vibration are obtained. Finally，the numerical sim- ulation of the analytical solution is carried

out and compared with the experimental data，which proves the rationali- ty of the conjecture