The Single-Action Principle

A system is strongly coupled when a change in one variable immediately affects all others. 

This paper introduces the Single-Action Principle, which proposes that control should be applied as a single coordinated action to the system as a whole. Rather than reacting to error through repeated correction, the method aligns control with the system’s current trajectory.

While nonlinear control theory addresses coupled dynamics, existing approaches remain largely based on feedback and decomposition. The Single-Action Principle differs by proposing a unified, trajectory-aligned control action without variable separation or relying on sequential correction.