Using the Kangaroo Plugin

For this diagram we need to use the Kangaroo component with springs as a force object. 

The kangaroo component looks like the one indicated below in the image. A spring force can be added by using the Springs component. 

In this case our input geometry is a line and output geometry is also a line that acts as a spring. The input Rest length in the Springs component is what lets us add a constraint of adjacency.

An other important input is the AnchorPoints in the Kangaroo system. Any number of points can be assigned as Anchor points. Any point assigned as an anchor point lets you move that point in the Rhino interface but also the constraints of rest lengths no longer affect the point assigned as anchor point.

Hence deciding which points can be the anchor points in the bubble diagram is quite critical.