Utilization of terrain elevation map in SLAM for unmanned aircraft

An approach to vision-based navigation system for autonomous navigation of unmanned aircraft with use of terrain elevation map is addressed. We considered simultaneous localization and mapping (SLAM) algorithm to be the system to which the digital terrain elevation data (DTED) is merged. The proposed algorithm acquires range measurement by line-of-sight (LOS) intersection and provides it to the SLAM algorithm. Simulation study verifies that the proposed method can estimate absolute position of unmanned aircraft even for the case that the features are not on the surface of the DTED. The uses of DTED makes the SLAM algorithm more feasible for airborne applications.