Nonlinear Dynamic Inversion with Actuator Dynamics: An Incremental Control Perspective

In this paper, we derive a sensor-based nonlinear dynamic inversion (NDI) control law for system with first-order linear actuators, and compare it to incremental (INDI), which has gained popularity in recent years. It is shown that, actuator dynamics, INDI approximates the corresponding NDI arbitrarily well under condition of sufficiently fast actuators. If bandwidth low compared changes states, derived following advantages INDI: 1) compensation state derivative terms, 2) well-defined error 3) exact tracking reference model, independent controller gains nominal conditions. The comparison well-established design method adds understanding control. additionally how quantify deficiency respect actuators finite bandwidth. results are confirmed through simulation roll motion fixed-wing aircraft.