In control theory, dynamical systems are in strict-feedback form when they can be expressed as where Here, strict feedback refers to the fact that the nonlinear functions
and
g
equation only depend on states
that are fed back to that subsystem.
[1][page needed] That is, the system has a kind of lower triangular form.
Systems in strict-feedback form can be stabilized by recursive application of backstepping.
[1][page needed] That is, This process is known as backstepping because it starts with the requirements on some internal subsystem for stability and progressively steps back out of the system, maintaining stability at each step.
Because then the resulting system has an equilibrium at the origin (i.e., where
) that is globally asymptotically stable.