[jitter] balloon string in jitter//stroke?

Hi. I'm working on an installation for which i'm creating a balloon that can be played with using video tracking. I'd like the balloon to have a nice and somewhat realistic moving string. Any ideas on how to do this? I've looked into the stroke function of the jit.gl.sketch object, but since I can't find any documentation on the use of these commands I can't work out how to use object. It would be very nice if someone could give me some advice. 

Thanx,

Anne-Jan