I'm scratching what hair is left on my head over this one. I need to model a cable operated assembly - very simple - the cable is attached at one end to a slider that, er, slides up and down a track, and at the other end it pulls on a lever . A spring provides the counter balance force. In between the slider and the lever the cable goes around a pulley.....and that is the problem.

Obviously the length of cable is fixed, but the section that goes round the pulley will vary, so I cannot set up a fixed length for the cable as I don't know how much cable is around the pulley at any one time as the angle around the pulley varies with the slider movement.

The belt mate doesn't work here. Any ideas how I can fix the length of the cable and get the resultant motion of the lever when I move the slider?