Last edited 9Dec13 by
Find this document at

Double Pendulum Project 2013 by Austin Graf


The double pendulum is a dynamic system that exhibits sensitive dependence upon initial conditions. This project explores the motion of a simple double pendulum in two dimensions by altering Bruce Sherwood’s VPython code to accurately represent the simple double pendulum at high energies and graphing the phase portraits of the system. It includes an interface via which the user can alter the two masses and the initial angles of the system.

Below lies a sample phase portrait for the system. Yellow displays the upper angle against its first derivative and cyan displays the lower angle against its first derivative.