Freedom and constraint in coupling networks

Kirchhoff’s circulation law has previously been adapted for studies of underconstraint. Here Kirchhoff’s cutset law is also adapted for studies of overconstraint. The two procedures are presented in tandem to emphasise their duality. The same tasks are then undertaken using dual virtual power methods. One is a new procedure for underconstraint that introduces the concepts of cutset motion and virtual action, dual with previously reported circuit action and virtual motion. Of the four methods described, the superior ones for each task are identified.