I am working on designing a flexible tube that will be held together by joints so they can rotate in two degrees of freedom (up/down and (left/right). The assembly uses the same part. When three of the same parts are mated together, I am able to move the parts freely by dragging one of the parts that are not fixed.
However, when the fourth part is inserted, I cannot move the model assembly.
I am using SolidWorks 2017 Standard.