Analysis of Measurement Errors in Rail Vehicles' Pantograph Inspection System

The paper presents an approach to evaluation of height measurement errors in laser scanning inspection system. The system, consisting of a laser line generator and a specialized camera, is dedicated to diagnosing carbon contact strips of railway vehicles' pantographs. While height measurement resolution is easily computable based on system parameters, determining the measurement error is troublesome due to numerous impacts. As width-to-height ratio of the scanned object is very high, typical patterns applied in references for error determination cannot be used. A set of real-case contact strips have been selected and used as patterns for determining scanning system errors. Both peak and RMS errors have been quantified to evaluate accuracy of wear estimation and defect identification, respectively