[Bakkot]

I did basically this in my first year of college! See [1].

(Note: code was never intended to be visible to the public, and this is old and bad. But hey, it works!)

http://kevingibbons.org/doublependulum.html

[leni536]

Your simulation has a "Daming factor"

[Bakkot]

... Well that's an ancient typo. Corrected, thanks.