Until now, trains often had to stop at a designated point so that the wheels could be measured individually, manually and in a time-consuming process. This is set to change in the future - with the '3D Wheel Measurement System' for the automated and faster measurement of train and suburban train wheels. The measurement takes place while the train is in motion. The system from Althen is suitable for measurement at maintenance locations as well as for operation on the tracks on the open route. The measuring system is installed around the rails. Five laser scanners measure the diameter, profile and distance of the train wheels and indicate the tolerances. A sixth laser is added to systems for streetcar wheels, as these wheels are in closer contact with the body of the train. Measurements are taken at an average speed of 50 km/h as trains pass by or before they roll into the station or maintenance area.

The sensor is connected to the tracks and records the data as soon as a train passes. Each wheel can be individually identified using an RFID code. To do this, a camera next to the railroad line reads the wheel numbers. An additional camera also identifies the vehicle using an RFID code. All data is sent directly and automatically to the technicians and mechanics via software. They therefore know the status of the wheels before the train arrives and only have to deal with those that actually require maintenance.

Sketch of the '3D Wheel Measurement System'.

© Althen

The software required for this can be integrated into an existing software solution, such as Aura. Aura is software that works according to a European rail industry standard and is already in use in many European railroad stations. In Germany, the '3D Wheel Measurement System' is still unique. "We are currently in talks with Siemens regarding a cooperation," says Thijs Haselhoff, Business Development Director at Althen.

To protect the sensors from the weather, they are embedded in opening and closing boxes. For self-cleaning, an override is generated as soon as the flap doors open, so that dust and dirt are blown out. In cold regions with extreme environmental conditions, such as Russia, where '3D Wheel Measurement' is already in use, additional heating elements are used. This ensures that the system works reliably even in extremely cold temperatures such as -30 °C to -40 °C. The same applies to regions with very high temperatures. Here, cooling systems are installed that enable operation in areas with temperatures of up to +50 °C.

Compatible and expandable

Thijs Haselhoff: "This new method of generating data for train and urban rail wheels will make maintenance much more effective in future."

© Althen

3D Wheel Measurement can also be expanded to include numerous additional functions. For example, a so-called weight-in-motion function can be integrated. This involves measuring the load of the train per wagon. Haselhoff: "The direction of the vehicle can also be recorded by additional components. Under certain circumstances, this can contribute to an early warning of danger." All data is combined and passed on to the customer.

'3D Wheel Measurement' is also compatible with additional components. For example, customers who do not want to do without the option of manual measurement can combine the system with handheld devices. A function that is useful when measuring new wheels that are not yet registered in the software. The measuring tools are integrated into the supplied software, for example Aura. A total of three manual tools are available: The following can be measured

the profile, the wheel diameter and the wheel distance. All tools are synchronized in a tablet (Windows). Apple software for the iPad is already under development. The system not only includes the hardware and software, but also sensors that ensure that it starts around 30 minutes before the train arrives. Haselhoff: "Of course, the '3D Wheel Measurement System' is calibrated and installed by us."

An upgrade of the system is already in development and will be released at the end of the year - with significant improvements: The improved frequency of the sensors will then even make it possible to measure at speeds of up to 350 km/h. This will make it the first measuring system capable of measuring high-speed trains at speeds in excess of 300 km/h.

Author:
Simon Federle works as a freelance journalist.