Airport Surface Conformance Monitoring

In this work, the State Dependent Transition Hybrid Estimation (SDTHE) Algorithm tracks aircraft on the airport surface in order to determine whether they are conforming to a prescribed taxi route from the Ground Controller. In general, hybrid estimation algorithms employ Kalman Filters tuned to various modes of vehicle motion (such as Constant Velocity, Constant Acceleration, Coordinated Turn, etc.) and a mode-switching mechanism (usually a constant mode transition matrix) to track a vehicle through its maneuvers. This works well to track a vehicle when its maneuvers are unanticipated, but the performance of hybrid estimation algorithms is improved when route information is known. Instead of assuming that the probability of a mode transition (For example: CV to CT) is fixed throughout a route segment, the SDTHE algorithm uses the vehicle's current state (position, velocity, etc.) and route information to ascertain whether a mode transition is likely. Accurate vehicle tracking with this algorithm enables testing for route conformance and conflict detection. The significance of the airport ground traffic application is increasingly evident due to the Federal Aviation Administration's recent "Call to Action" for Runway Safety.