The Position constraint lets you apply a source object (or objects) to constrain the translation of a target object.
Position constraint
When you drag an object into the Source 1 field, another source (Source 2), is added to the Objects pane. If you drag a second source into Source 2, the position of the constrained object is derived from the position of the two source objects.
You can have as many sources as you want, which let you create complex Position constraints.
For example, in following figure, A, a constrained object to the left of three objects in a triangle formation is shown. When the constraint is activated, the constrained object moves to become equidistant from the three source objects to B.
Position constraint A. Pink marker: a constrained object B. The Position constraint is activated
