Construction and technical condition of current collectors is crucial to reliability and safety of railway transportation. According to the Technical Specifications for Interoperability railway vehicles in the European Union should be equipped with carbon contact strips. Excessive wear or defects of contact strips degrade the capability of undisturbed power transmission, cause faster wear of contact wire, and can even result in catenary rupture. The technical condition of contact strips is assessed manually during periodical services performed by rolling stock operators. However, rail infrastructure companies are also interested in pantographs inspection of the vehicles running within their network. A novel inspection system for current collectors contact strips is presented. The system uses a specialized camera and a laser line generator to scan the contact strips surface. The scanning is performed on a railway line, when a vehicle passes the inspection point. A prototype of the system was tested in the target conditions and sample scanning results were recorded. Basic algorithms for automatic analysis of contact strips wear were introduced. Accuracy and repeatability of the measurement were assessed. The potential of commercial implementation of the system was confirmed.

Electric rail vehicles use current collection system which consists of overhead contact line and a current collector (pantograph) mounted on the roof of a vehicle. A pantograph is equipped with contact strips, which slide along the contact wire, ensuring steady electric contact. Contact strips are made of carbon layer, fixed to an aluminum carrier. The carbon layer wears down due to friction. Using overly worn contact strips increases the rate of contact wire wear and, significantly, the risk of contact line damage. Therefore, thickness of carbon strips has to be inspected periodically. In previous work a 3D-scanning system has been proposed for recording data of contact strips when vehicles pass an inspection point on a railway line. However, the system has to be complemented with data analysis algorithm to estimate the thickness of the carbon layer. Data processing has to be performed quickly and automatically to prevent faulty pantographs from being used. The main difficulty of wear analysis is caused by diverse altitude and tilt of scanned contact strips. To determine the smallest thickness of carbon layer, the carbon surface data have to be normalized with respect to an aluminum carrier. The location and shape of the aluminum carrier can be extracted from the registered data. Due to the fact that the profile of the carrier is highly distorted, a robust Whittaker approximation algorithm has been proposed in order to deal with the noise and the missing data.

The paper describes the contactless electrical energy transfer system (CEETS), by which electrical energy may be transmitted, without electrical connection or physical contact, through the large air gap. In this case energy is transmitted via coreless transformer. Coupling between the coils changes and depend on dimension of air gap. The efficiency of CEETS is mainly depended on the transmission frequency. Additionally large leakage inductances may be compensated also in resonance condition by adding capacitors to the coils. The article presents theoretical analyses and simulation results of transformer equivalent circuit with capacitors. Theoretical developments are compared with practical measurements from a prototype contactless system.

The problem of the reproduction of the railway geometric layout in the global spatial system is currently solved in the form of measurements that use geodetic railway networks and also, in recent years, efficient methods of mobile positioning (mainly satellite and inert). The team of authors from the Gdańsk University of Technology and the Maritime University in Gdynia as part of the research project InnoSatTrack is looking for effective and efficient methods for the inventory of railway lines. The research is part of a wider investigation BRIK (Research and Development in Railway Infrastructure, in polish: Badania i Rozwój w Infrastrukturze Kolejowej). This paper presents a comparative analysis of the problem of the reproduction of the trajectory of the measuring system using tacheometry, satellite measurements made using a measurement trolley, and mobile satellite measurements. Algorithms enabling the assessment of the compliance of satellite measurements with classic tacheometric measurements were presented. To this end, the authors held measurement sessions using modern geodetic instruments and satellite navigation on a section of the railway line. The results of the measurements indicate the convergence of the level of accuracy achieved by different measuring techniques.

The article discusses an important issue in connection with the technique of mobile Global Navigation Satellite System (GNSS) measurements of railway track coordinates, which is digital filtering performed to precisely determine railway track axes. For this purpose, a measuring technique is proposed which bases on the use of a measuring platform with a number of appropriately distributed GNSS receivers, where two of them determine the directional base vector of the platform. The receivers used in the research had high measuring frequency in the Real Time Kinematic (RTK) operating mode and enabled correction of the obtained results in post–processing. A key problem discussed in the article is the method for assessing the quality of the measurement results obtained from GNSS receivers, and their preparation for further processing making use of geometrically constrained parameters of the base vector and specialized digital filtering, among other elements, to precisely determining the track axis. The obtained results confirm the applicability of the used method of GNSS signal processing.