Increasing Accuracy in Train Localization Exploiting Track-Geometry Constraints

Abstract

Train-borne localization systems as a key component of future signalling systems are expected to offer huge economic and operational advances for the railway transportation sector. However, the reliable provision of a trackselective and constantly available location information is still unsolved and prevents the introduction of such systems so far. A contribution to overcome this issue is presented here. We show a recursive multistage filtering approach with an increased cross-track positioning accuracy, which is decisive to ensure track-selectivity. This is achieved by exploiting track-geometry constraints known in advance, as there are strict rules for the construction of railway tracks. Additionally, compact geometric track-maps can be extracted during the filtering process which are beneficial for existing train localization approaches. The filter was derived applying approximate Bayesian inference. The geometry constraints are directly incorporated in the filter design, utilizing an interacting multiple model (IMM) filter and extended Kalman filters (EKF). Throughout simulations the performance of the filter is analyzed and discussed thereafter.

An Open Data Set for Rail Vehicle Positioning Experiments

“…Different map-supported approaches for positioning include [17]- [21]. Approaches without mapsupport include [7], [22], [23]. Approaches with sensors beyond this data set include [24]- [26].…”

Generating Compact Geometric Track-Maps for Train Positioning Applications

“…We assume to start with the results of the localization filter we presented in [1]. Along with the position solution this filter estimates some of the track's geometric parameters which conveniently serve as initialization for the map generation process.…”

“…1. The detailed simulation procedure and parameters are described in [1]. All further explanations are illustrated using this example data.…”

“…1) Track Geometry Identification: We assume that the missing track-geometries can be concluded from the following knowledge [1], [25]: Railway tracks only consist of three basic geometric shapes which are straights, transitional arcs and circular arcs. A straight can only be connected to a circular-arc with the help of a transitional-arc and vice versa.…”

“…From this overview it will become apparent that there are hardly any adequate methods to generate suitable track maps for the purposes described above. Therefore, we will present a new approach to generate compact geometric * Control Methods and Robotics Laboratory, TU Darmstadt, Germany {hanno.winter,stefan.luthardt,vwillert,adamy}@rmr.tu-darmstadt.de track-maps based on the results of a localization filter we presented in our previous work [1] motivated by [5].…”