Linear positioning of railway objects

The article provides an explanation of the issue related to the linear positioning of railway objects in the context of preparing site data for automatic train protection systems, such as the European Rail Traffic Management System/European Train Control System (ERTMS/ETCS). This paper identifies and compares current approaches for an object’s position based on a line chainage for orientation and documentation purposes, as well as the object’s position based on a track axis for the calculation of real world distances, along with providing examples of measurement systems and presenting conclusions from test runs for ERTMS/ETCS Level 2 purposes.