You can create a Component to Component constraint to attach hair system curves to other nHair curves or to other Nucleus objects components. For example, you can constrain selected hair curve CVs to the vertices of a passive collision hair clip or barrette so that it holds the hair in place.
If you selected target components on a non-Nucleus object, that object will be made a passive object when the constraint is created.
The hair curve CVs you selected are now constrained to the selected target vertices, and they are now connected to the nHair system's Maya Nucleus solver through a dynamicConstraint node.
The preset properties on the dynamicConstraint node determine the constraint’s type (in this case, a Component to Component constraint) and how it behaves. For example, you can create a Component to Component constraint with the following attribute settings: