Nonlinear dynamic inversion reconfigurable controller utilizing a fault tolerant accelerometer

A modified derivation of nonlinear dynamic inversion provides the theoretical underpinnings of a reconfigurable control law for aircraft that have suffered combinations of actuator failures, missing effector surfaces, and surface damage. The approach does not require a model of the baseline vehicle, but does require feedback of effector positions to accommodate actuator dynamics and accelerations, which contain information pertaining to any aerodynamic change. An accelerometer failure detection and isolation (FDI) system is implemented, allowing up to three independent failures as long as they are in different axes. Experimental results show that the FDI system also improves the robustness to accelerometer uncertainties. An advanced tailless aircraft is used to demonstrate the concepts. The simulation includes accelerometer noise and bias as well as accelerometer and actuator failures.