Digital brake force measurement system for trains supports Swiss Federal Railways (SSB)

The new Brake Force Measurement Solution (BFMS) from Kistler is paving the way for efficient servicing and maintenance of Switzerland's local trains. This compact solution comes in a wheeled case with hardware and software designed for modular expansion – so it's easy to add extra measurands such as pneumatic braking pressure.

How can digital measurement technology optimize train maintenance processes to speed up servicing of local trains and get them back on the rails? For the answer to this question, let's look at a pilot project where Kistler is collaborating with SBB's Eastern Switzerland Regional Vehicle Maintenance Center (RICO) in Oberwinterthur. Working to a tight schedule, RICO maintains and repairs trains in SBB's Thurbo and Seehas fleets – even performing conversions when necessary.

The majority of trains in the serviced fleets consist of articulated railcars with multiple sections that operate suburban railway (S-Bahn) lines and regional routes. Especially in the local traffic segment, requirements for reliability and safety are high. End customers expect punctuality and reliability. The only way to achieve those goals: efficient, safe handling of all necessary servicing work. Meeting deadlines is absolutely critical. This creates more responsibility for the service technicians: regular checks must be completed quickly and reliably on the trains so they can resume service.

Customized measurement technology optimizes the servicing process

As their partner to achieve ongoing process improvements, RICO invited measurement technology expert Kistler on board. The first challenge: to optimize brake force measurements. These measurements play a crucial part in maintenance, and they are governed by both Swiss and international regulations. “Our previous processes were prone to faults and not very efficient. That's why we were delighted with Kistler's offer to analyze the entire process and optimize it across the board on the basis of a development partnership”, says Ranieri Baratto, Fleet Technician at SBB RICO.

To achieve this, Kistler's Digital Solution Engineering Team considered not only the entire measuring chain but also the complete process at the customer's site. Goals were defined: improvements to data acquisition and evaluation, and – the top priority – a system that would be simple to handle and operate. The partners collaborated to develop an efficient working procedure supported by customized measurement technology from Kistler – including hardware as well as software. This was a multi-stage process that included discussing and testing the practical suitability of the solution, with adaptation of the components as necessary. 

The new BFMS (Brake Force Measurement Solution) developed by Kistler for RICO comprises four 9303A1B brake force sensors, the compact version of the KiDAQ modular data acquisition system, and a notebook with the application-specific software. All the components fit into a rugged hardshell case for easy, flexible transportation between railcars. The measurement application software can also be controlled from the company tablets issued to RICO employees.

Another benefit: the system's design allows pressure sensors to be integrated in the future. This would make it possible to compare the real force built up on the brake disks directly with the pneumatic pressure present in the braking system. So with just one measurement step, conclusions could be drawn about the entire braking system.

User-friendly, efficient and future-proof

The software solution to be used in the system was a top priority for RICO. It had to meet traceability requirements and also enable automated generation of documentation and reports. The Kistler Digital Solutions Engineering Team responded to this challenge by developing a proprietary application based on KiStudio Lab that can map RICO's servicing processes with high precision. The first step is to select the train type. Then, users are guided through the process step by step with graphic displays showing the sequence of bogies and the number of brakes.

Thanks to the four brake force sensors, one complete bogie can be measured in just one process step. At a glance, the software shows the brake force measured per wheel and bogie as well as the action of force over time. Key process-specific values are classified directly and compared to specified reference values. To ensure security, all series of measurements are stored both locally and in the cloud. Previous measurements are available at any time so they can be included in holistic data analyses.

Kistler has also given plenty of thought to protecting the customer's investment. That's why the solution has a consistent modular design so it can be extended at any time. As necessary, operators can use additional measurement modules that are controlled centrally by the same software. This opens up the prospect of efficient measurements on long trains with as many as six cars and seven bogies – in just one step. Ranieri Baratto sums up the project in positive terms: “Our collaboration with Kistler is underpinned by a high degree of trust and a constructive approach, enabling us to continue improving the availability of our rolling stock. With Kistler on board, we have an important partner in our efforts to step up the automation of servicing and maintenance.”