Fourmilab Double Pendulum is a physical model of a double pendulum system in which two masses (“bobs”) swing on frictionless bearings on rods, with the first mass connected to a fixed hub and the second mass swinging freely beneath the first. This simple system exhibits extraordinarily complicated and chaotic motion, which varies dramatically as parameters of the system (masses of the bobs, lengths of the rods, initial displacements of the masses) are varied. Fourmilab Double Pendulum models an ideal double pendulum system, with no friction or air resistance, and allows you to change the parameters of the model and observe the results. Facilities allow tracking the chaotic motion of the lower bob, displaying its path as the system evolves. The model is fully scriptable with commands supplied in notecards in its inventory and scripts may define pop-up menus through which an avatar may interact with the model.
This repository contains all of the software and resources, including programs in Linden Scripting Language, notecards, and development documentation, tools, and resources used in the model and its development. The actual model is built within Second Life and these components are installed within it.
The complete package is available for free in the Second Life Marketplace. This repository contains everything in the model (except the prims, which are objects built within Second Life), plus additional resources for developers who may wish to extend or adapt the model as they wish. The model is delivered with "full permissions": those who obtain it are free to copy, modify, and transfer it to other users within Second Life.
A video demonstration is available on YouTube.
All of this software is licensed under the Creative Commons Attribution-ShareAlike license. Please see LICENSE.md in this repository for details.
Please see the Fourmilab Double Pendulum User Guide for details.