Brilliant, thank you very much. It was the addition of the special revolute joint at the end to prevent it being a planar loop that was eluding me.

I see. You can modify my above model slightly: This will generate a simulation that looks like this: You can add forces with the `Modelica.Mechanics.MultiBody.Forces` library.

Diagram below of what I would like to achieve as a system, once stable I would like to place forces and/or accelerations to the red nodes. I hope this makes sense...

Thanks for the response. What I'd like to create are two supports, with a prescribed distance between them. Between these two supports will be a series of links, whose total combined length would be greater than the distance between the supports. Using revolute joints between each link, I would like to model the links so they drape between the two supports under their selfweight. The idea being that I could reverse the geometry, include rotational springs on the revolute joints and make a springy arch that can support loads, with its load carrying capacity being driven by the stiffness of the springs. I hope this makes sense, I'm not near a scanner for a few days else I would draw a sketch.

Creating Supports in SystemModeler ....