Trajectory evaluation using repeated rail-bound measurements

Many applications today require the precise determination of the position and orientation of a moving platform over time. However, especially in safety-critical areas, it is also important to derive quality characteristics of the trajectory estimation. This allows verification that sensors are operating within the precision and accuracy required for the application. In this paper, we propose a methodology for trajectory evaluation and address the challenges involved. Our approach is based on repeated measurements obtained using a closed loop rail track and allows the evaluation of the trajectory estimation in terms of precision and accuracy. Starting with the chronologically ordered raw data, the methodology first spatially sorts the measurements and then approximates them to a mean trajectory. The deviations between the single pose observations and the mean trajectory indicate the precision of the observed poses. With the addition of a higher-order reference, our methodology also determines the accuracy of the system under test. The applicability of our method is demonstrated by an exemplary evaluation of a low-cost inertial navigation system.