How can i simulate a Rubber band?

[josemendez]

And there has a problem,in the component ObiPinConstraints when i click Add Pin Constraint there is no response.

Hi johnny!

You need to select which particle(s) you need to add the pin constraint to (use the particle editor). Then, click Add Pin Constraint. Take a look at the docs:
http://obi.virtualmethodstudio.com/tutor...aints.html