Sensitivity analysis of object space geometry for TLS-aided navigation

In GPS-impeded environments, due to cumulative error characteristics of inertial sensors, a GPS/IMU system is unable to maintain high navigation accuracy during extended GPS outages. In particular, vegetated and urban environments present unique challenges in applications where high absolute and/or relative navigation accuracy is required. To remedy this deficiency, a method that integrates 3D laser ranging to deployable spherical targets with an inertial system to enable centimeter-level navigation accuracy of a mobile unit under heavy canopy is discussed here. This paper is focused on the requirements for geometry and spatial distribution of the spherical targets and their impact on the achievable navigation accuracy. The sensitivity analysis is performed based on simulations as well as the actual field test data.