INTRO: This summer Eurailscout GB Ltd launches the UFM160 high speed infrastructure measuring train on the UK network. The two-car unit is due to inspect most of Network Rail’s Southern Region later this year

BYLINE: Nick Oversier

Technical Director, Eurailscout GB Ltd

EURAILSCOUT GB is a newly-formed joint venture of Carillion Rail and Europool bv, set up to take advantage of a partnership that combines expert knowledge of the UK railway industry and proven technology, knowledge and experience of measuring railway infrastructure in Continental Europe. In a unique venture, the company has developed a 160 km/h infrastructure inspection train that it will operate on Network Rail’s Southern Region.

Europool bv, a Dutch-German company, owns several measuring vehicles operated in Continental Europe by Eurailscout bv, based at Amersfoort in the Netherlands. Until now, Europool’s flagships have been the UST96 ultrasonic testing train, which earlier this year was enhanced by the addition of eddy-current rail inspection equipment, and the UFM120 infrastructure measuring train. These two trains operate regularly in 10 European countries. The success of the UFM120 led Europool to order a second measuring train from Plasser & Theurer of Austria in 1999. Its 160 km/h maximum speed led to the designation UFM160.

This train had to be able to operate at higher speeds than its predecessor to meet pathing constraints. It also had to comply with the operational and safety standards of the railways in Continental Europe and those in the UK. This proved to be a real challenge as the UK regulations in some cases turned out to be incompatible with those in Europe.

During the tendering process for high speed measurement contracts that Railtrack, Network Rail’s predecessor, was letting in early 2001, Europool and maintenance contractor GTRM set up Eurailscout GB Ltd to operate the UFM160 jointly. This company was also charged with introducing ’trainborne inspection’ to reduce the frequency of foot patrols, partly using high-quality video recording.

The UFM160 was completed in Austria almost one year ago. The vehicle is equipped with German Railway’s Indusi train protection and radio systems and is approved for use on the DB network. The train also had to be registered for use in the Netherlands, requiring fitment of ATB train protection and Dutch telecommunications equipment. Compatibility with the NS infrastructure also had to be proven, necessitating a six-week testing period in the Netherlands. Once this was completed, the train was moved to Derby by ferry and road trailer in early August 2002.

It took almost nine months to have the vehicle approved for service in the UK. From early April the UFM160 underwent commissioning trials at the Midland Railway Centre at Butterley, one of numerous preserved railways in the UK. Measuring systems were calibrated and tested, and the crew trained for their challenging tasks.

International role

The UFM160 is a two-car train with a mass of almost 136 tonnes. As delivered, it is fully equipped for service in the UK, Germany and the Netherlands. It is designed to UIC standards for operation in other countries, subject to checks for compliance against national infrastructure standards. Cross-acceptance of the German certification process means the unit could run in Austria, Switzerland and Slovenia without further clarification.

The driving cabs at each end feature several train protection and safety devices, plus four different train radio systems; in the UK these are the National Radio Network and Cab Secure Radio.

The train is powered by two MAN underfloor diesel engines, each with a continuous rating of 550 kW, while the measurement and inspection equipment is powered by two on-board generators. All four bogies are disc-braked. The two inner bogies are unpowered so as to create the best possible conditions for the measurement frames. These frames are specially designed to support the delicate measurement systems.

The interior of the 48m long train is divided into several sections. The generator compartments, a small workshop, and a computer and systems area are separated from the measuring control room, an office and a visitors’ room. A small kitchen, a bedroom and sanitary facilities mean that the train can accommodate up to 12 people during measuring shifts.

Track measurement systems

The UFM160 offers a wide range of non-tactile measurements of infrastructure parameters using optical and inertial systems. All measurement systems are controlled by software supplied by Plasser American Corp which also manages acquisition and storage for off-board post-processing and analysis. All acquired measurement and calculated values are monitored in real time, and depending on predefined thresholds and specified conditions, exceedences are detected and reported for immediate submission to the customer.

At the heart of the train is the track geometry measuring system. The UFM160 is equipped with inertial positioning and orientation which is linked to laser-based, optical and high speed gauge measuring systems. Parameters such as gauge, superelevation, longitudinal profile and alignment are used to calculate twist, curvature and other values.

The exact geographical location is determined using a detailed database of points of interest (synchronisation points), GPS and differential compensation. Positioning and synchronisation is achieved automatically. The database can be established by a track survey or by linking to an existing geographical information system. Depending on the quality of the database and local circumstances, accuracy can be achieved within a few tenths of a metre.

A laser-based rail profile measuring system automatically detects the type of rail - currently 13 types have been identified in the UK alone, measures the actual profile of the rail and calculates rail wear, cant and gauge. This is complemented by an optical system to inspect the rail surface and rail fastenings which automatically detects irregularities on the rail surface and missing fastenings. The effectiveness of these systems depends very much on the visibility of the rail - too much ballast on the sleepers or on the foot of the rail will affect the output.

An inertial corrugation measurement system that is still experimental is being tested on the UFM160. This enables measurement of rail corrugation in four different wavelength categories using high-order digital filters.

OLE inspection

The position, height and stagger of the overhead line equipment is measured using another laser-based system which is capable of detecting and identifying up to four different wires; it also determines the location of the masts. These measurements can be carried out with the overhead wire unloaded, or to simulate working conditions, with a dummy pantograph raised.

The UFM160 is equipped with high-resolution digital cameras. One of these is mounted on the roof to monitor the OLE. Two further cameras are fitted at each end of the train to record the track and trackside environment. Recorded video footage is identified by marking location, date and time and stored for off-board analysis of track, structures, vegetation and so on.

The measurement and control system is designed to handle all requirements of the on-board equipment and to process data in real time to meet customers’ requirements. It can be configured to suit different users and can be customised to calculate any relevant parameter or generate reports.

Data analysis

The on-board software systems, directly connected to the data acquisition hardware systems and, through the network, to all measuring sub-systems, enable real-time recording, storage and viewing of all measured values. The display and analysis software module can be operated from any workstation on the on-board network. It displays and prints charts of measured data, and also generates exception reports. The exception reports, although unedited, can be transferred to the customer for analysis and immediate action if required.

For the post-run analysis of measured data, to validate datasets or to re-run the analysis with different settings, both the train software systems can be used or dedicated software designed and built for this purpose. In Continental Europe the UFM160 outputs are accessed using a comprehensive software system called IRIS, and they can be converted into any format that the customer specifies. This enables open connection to other software systems.

Use of the proper analysis tools permits data to be examined from different runs, and it is possible to zoom in on identified exceptions. The tools also permit trends to be identified, detecting deterioration and creating infrastructure quality indicators. All these can be used to draw up maintenance programmes, plan renewals and improve asset management. If required, progress can be recorded with the help of performance indicators.

Constant improvement

Eurailscout bv devotes much effort to evaluation of new and improved measurement systems that can be installed on its inspection trains. The company strives for open communications with its customers, and in this way it is able to make state-of-the-art technology available to them and to provide tailor-made equipment if required. Another benefit of this policy is the synergy from sharing knowledge and expertise across Europe.

At the moment the company is developing a third rail measurement system for use on Network Rail’s 750V DC network south of London. The position of the conductor rail is to be measured as well as the profile of the rail. For this purpose a laser-based system similar to that used for the running rail profile is about to be fitted to the UFM160.

Capturing video streams or high-definition images of exceedences, special locations or objects in real time is being developed. This will serve to support the measurement of data anomalies and will allow viewing of the infrastructure without having to leave the train.

We have found that our European customers are very keen to use visual inspection of selected sites with high-definition video recordings. A significant problem is how to handle the enormous amount of image data, and ways are being sought to limit the volume of data. One option is to pre-select a set of specified objects such as points and crossings where it is easier to measure exceedences.

The UFM160 is one of two high speed multi-system measuring trains being developed for the UK. The purchase of such trains is a major investment, and operating costs are significant. By measuring several infrastructure parameters in a single pass, better use is made of the investment. Apart from this economic advantage, opportunities are open to analyse multiple values measured at the same time and under equal conditions.

In June the UFM160 was programmed to run for the first time on Network Rail’s Southern Region, with a series of flagship runs to allow both Network Rail and the infrastructure maintenance contractors to appreciate the UFM160 and its measuring capabilities. After acceptance trials the UFM160 will be used to inspect most of the Southern Region network and the Channel Tunnel Rail Link. Work is expected to start in the second half of the year.

CAPTION: The UFM160 test train has already been certified for operation in Germany and the Netherlands

CAPTION: The UFM160 began its UK commisioning trials at the Midland Railway Centre in April

CAPTION: Track measuring equipment is supported from two frames around the inner bogies