My design consists of 2 pulleys (4in dia and 1 in dia) and a belt.  The belt is not continuous, it is fixed at both ends.  This arrangement is used in a counterbalance for  lifting. one end of the belt is fixed to a stationary frame, the other is fixed to the load that is allowed to move. I would like to model this in both the lifted and lowered position with the belt adjusting accordingly, is it possible?