This example shows two models of a double pendulum, one using Simulink® input/output blocks and one using Simscape™ Multibody™.
The Simulink model uses signal connections, which define how data flows from one block to another. The Simscape Multibody model is built using physical connections, which permit a bidirectional flow of energy between components. Physical connections make it possible to add further stages to the pendulum simply by using copy and paste. Input/output connections require rederiving and reimplementing the equations.
The initial angle for each joint is defined by a MATLAB® variable. The annotations on the Integrator blocks show the initial angles of the joints with respect to the world frame.