Double Pendulum

Every physics department needs a double pendulum, so here's how I built ours. The big improvement is that the bottom pendulum can be locked in place. This turns the chaotic double pendulum into a non-chaotic physical pendulum.

This project was originally published 31.Aug.2007 on instructables.com as part of their Science Fair contest.


Introduction

I'm going to be lazy and skip writing a big long introduction or explanation for this and just focus on how mine is put together. The links below are good starting points for background info.

http://en.wikipedia.org/wiki/Chaos_theory

http://en.wikipedia.org/wiki/Double_pendulum

http://en.wikipedia.org/wiki/Pendulum_(mathematics)

http://hyperphysics.phy-astr.gsu.edu/hbase/pendp.html

http://www.myphysicslab.com/dbl_pendulum.html (Simulation)

http://www.physics.usyd.edu.au/~wheat/sdpend/ (a neat version made from two square plates).


Top Pendulum Assembly

Top_Pendulum_Assembly_1.jpg Top_Pendulum_Assembly_2.jpg Top_Pendulum_Assembly_3.jpg Top_Pendulum_Assembly_4.jpg

Top_Pendulum_Assembly_5.jpg Top_Pendulum_Assembly_6.jpg Top_Pendulum_Assembly_7.jpg Top_Pendulum_Assembly_8.jpg Top_Pendulum_Assembly_9.jpg


Bottom Pendulum Assembly

Bottom_Pendulum_Assembly_1.jpg Bottom_Pendulum_Assembly_2.jpg Bottom_Pendulum_Assembly_3.jpg Bottom_Pendulum_Assembly_4.jpg

Bottom_Pendulum_Assembly_5.jpg Bottom_Pendulum_Assembly_6.jpg Bottom_Pendulum_Assembly_7.jpg Bottom_Pendulum_Assembly_8.jpg Bottom_Pendulum_Assembly_9.jpg


Complete Double Pendulum Assembly

Complete_Double_Pendulum_1.jpg Complete_Double_Pendulum_2.jpg Complete_Double_Pendulum_3.jpg

Complete_Double_Pendulum_4.jpg Complete_Double_Pendulum_5.jpg Complete_Double_Pendulum_6.jpg Complete_Double_Pendulum_7.jpg


CAD Files

Download an AutoCAD .DWG or a .ZIP file of parts from Alibre Design Xpress.

Video


Please send any questions or comments to me at sbtroy@phys.washington.edu.

Go back to my home page.

Go to the Lecture Demonstration webpage.


This page was first uploaded on 31.August.2007 and last updated on 24.August.2010.