DEGRADED ACTUATOR DETECTION

An actuator control system is disclosed that includes an actuator continuously movable between multiple positions. The controller is configured to command the actuator to a desired actuator position and to apply the command to an actuator model. The controller is configured to compare the modeled and actual actuator positions to determine if the position difference exceeds a fault detection accommodation limit and if the position difference is within a band that is different than the fault detection accommodation limit. The controller is configured to calculate a threshold, which is based upon an estimated load on the actuator. The controller is configured to calculate a band comprised of the threshold applied to the modeled position and to determine if the actual actuator position is within the calculated band. The threshold is calculated at regular intervals, and a fault is declared if the actual actuator position is outside the band for a number of consecutive intervals.