Up until now, DPMLJ workers have checked the condition of tram lines with manual or mobile gauges. They had to walk the track and write down the measured values manually. “It was an uncomfortable and lengthy measurement of a rather local nature,” said Martina Poršová, spokeswoman for the transport company.
The new device should make this activity much easier for them. “The new measuring device is attached to the chassis of the tram, everything is automated and all measured data is stored in a computer. In addition, we can measure the entire tram line in a short time. We can measure repeatedly during the year,” added Ludvík Lavička, the operational director of the transport company.
The designed device is primarily intended for T3 tram bogies. These trams were also tested. “In addition to the fact that the device can detect potentially dangerous places on the track, the obtained results can also be used in the framework of long-term effective planning of track repairs,” said Michal Starý, head of the research team of the Faculty of Mechanical Engineering and the Institute for Nanomaterials, Advanced Technologies and Innovations.
The essence of automatic measurement is based on lasers, cameras and satellite navigation. “Such a system is already used to monitor the condition of train tracks. But trams have a significant part of the tracks embedded in the ground level, which made measuring with the help of lasers and cameras impossible,” said Poršová.
The team from the University of Liberec managed to solve this problem. “With each measuring unit, we project a laser beam perpendicular to the rail and take an image with a camera. So we get two images – left and right rails. The software evaluates these two images and obtains the current gauge. This was a difficult task. These are two separate devices, but we can calibrate them together so that they measure correctly and absolutely accurately,” said Ondřej Matúšek, a member of the team from the Faculty of Mechanical Engineering. According to him, thanks to GPS satellite navigation, they also know exactly in which part of the track there is a problem.
The university intends to offer the developed equipment to other transport companies in the country and abroad. The newly founded university company The University Company TUL (TUC) will help with the search for potential commercial partners.