Investigating the drag impact on pendulum through numerical models and the stability analysis

As a traditional physical model, the pendulum plays a crucial role in the dynamics. However, most research focuses on the ideal pendulum structure which deviates from reality. In order to study the pendulum in practical situations, this paper not only investigates the ideal model but also the simple pendulum motion with drag. Firstly, this work derived analytical and numerical solutions of the simple pendulum motion equations, which come from physical phenomena, and compared these two solutions. Moreover, this study investigated the error of this numerical model and accomplished further research on demonstrating the conditions to meet the stability of the model.