Success Story

Tunnel construction safety – how to see through rock

Where GPS comes up short, VMT GmbH offers a unique solution for accurately locating personnel and devices on tunnel construction sites. Zühlke developed the technology and assisted VMT with ongoing in-house development.


To add value to its solutions, VMT wanted to offer its customers an indoor location system. The system would in particular be used to improve staff and equipment safety on tunnel construction sites. The company wanted to develop a portal which would eventually operate as a central control centre for such sites.

VMT chose Zühlke for its ability to deliver a complete solution – from requirements analysis and the solution architecture, to usability engineering and design – from a single source. The project also provided the VMT development team with the opportunity to gain additional experience with agile methods and enabled it to utilise these methods in its ongoing in-house development process. As a result, Zühlke has also helped improve the efficiency and profitability of VMT’s in-house development.


Zühlke based its approach on DECT, a real-time location system (RTLS) and HTML5. The first step involved implementing a location solution, including infrastructure monitoring and system status reporting.

A contemporary HTML5 single page application was used to provide the user interface, which was accessible from anywhere in the tunnel network. This ensures that all changes in position are recorded immediately and are visible in the user interface. The solution incorporates two different location models – coarse location at the tunnel segment level via DECT and a more precise location to approaching 1 metre accuracy using RTLS.

A clear visual display design helps users when making safety decisions. The system allows manual changes to relevant parameters to be made at any time. These changes are visible throughout the network, ensuring that the displayed view of the tunnel site is the same across all devices at all locations.

Client benefits

  • Innovation – VMT has added a new, innovative solution to its product portfolio.
  • Time to market – Zühlke’s expertise ensured that the project was delivered within the tight timeframe required by VMT customers.
  • Team enabling – the VMT team were familiarised with agile development and are now using this in their own in-house projects.