Crash tests with high measuring ranges
The world’s largest provider of rail transport technology has worked for years on optimizing its railway vehicles. In its own technology and product development center the Chinese corporation regularly carries out extensive crash and component tests on its high-speed trains. The declared objective of this extensive test program is to minimize personal injury and material damage in the event of a crash, and to sustainably develop rail transport. In tests to determine what impact forces operate on the trains and their components, the company relies on measurement technology provided by Kistler. Since the end of 2017 a ground-breaking Kistler application has been in use in the crash hall: the world’s first ever crash wall for high-speed trains.
Christof Sonderegger, the Product Manager for Test & Measurement at Kistler, is responsible for this major project. “This is the first time in the entire history of our company that we have had the opportunity to handle an application like this. With the crash wall for high-speed trains we enter a measurement range that is up to twenty times higher than in the typical crash tests performed in the automotive industry. Cars are driven into the wall with up to 64 kilometers per hour, while our Chinese client’s trains crash into the walls with up to 72 kilometers, generating a force equivalent to a mass of 10,000 tons.“
Modular concept with freely combinable sensors
The challenge for Kistler was to develop a custom-built crash wall, which could not only handle the high impact forces of the high-speed trains, but was also modular and extendable. On top of that Kistler had to adhere to a very tight delivery schedule and was required to provide a full turnkey solution. “We were only able to handle such a demanding task thanks to outstanding internal cooperation,” explains Sonderegger.
After an intensive engineering phase lasting several weeks, the measurement technology experts were able to develop a crash wall with a total of six segment plates, each of which allowed for 36 sensors to be installed on them. A key advantage is that the sensors can be flexibly combined with each other and cover all load requirements. If required, the crash wall can be extended by a further three segment plates, again, each with additional sensors. In the Chinese client’s crash wall the Kistler engineers installed 1-component force sensors with measuring ranges of 700 kN, 2.5 MN, 5 MN and 10 MN. The sensors come ready calibrated and guarantee constant measuring precision over a broad force range.
Ground-breaking DTI technology
The digital electronics, the so-called DTI (Digital Transducer Interface) technology, is integrated into Kistler’s force sensors.
"The DTI technology has already been successfully used for several years in vehicle safety, driving dynamics and operational stability. Our engineers were also able to integrate this unique technology for our client in China."
Christof Sonderegger, Product Manager for Test & Measurement at Kistler
In sensors with DTI technology, the signal is digitalized in the sensor and relayed with a bus. The sensor data flows interference-free into the central Kistler DTI logger and is transferred into the computer and recorded via Ethernet.
Excellent on-site service
The sensors, electronics and testing equipment were produced in Winterthur (Switzerland), where Kistler is based, and the measurement technology experts had the segment plates manufactured by a local supplier. The Kistler Tech Center in Shanghai was responsible for the segment plates system test and installation at the client’s facility. Finally, the custom-built crash wall was installed in the Chinese corporation’s technology and product development center. Kistler’s crash wall has been in operation since the end of 2017. “Our client is very satisfied with the modular concept with freely combinable sensors and the robust interface. For future tests the company plans to order further sensors and segment plates from us,” says Sonderegger.