Besides modern facilities adopted during the reconstruction, it was desired that the stadium have an inside mobile roof (above the playing surface). This has made it easier for the largest mobile roof construction. It consists of a membrane structure supported by steel cables that can be stretched or closed in a very short time.
The opening and closing of the roof are fully automatic, at the push of a button. While the roof is open, the membrane gathers to the center inside a video-cube (31m2 and 30t, on whose side surfaces are monitors).
Closing the roof has two main stages:
- The membrane is stretched by means of electric motors up to the final position
- The membrane is taken of hydraulic aggregates for blocking and stretching in the final position
Due to symmetry shape the stadium was chosen a system composed of 32 units arranged in 4 sectors with 8 hydro sectors. An electro-hydraulic aggregate has a 1.5 kW electric motor, a winch and a hydraulic locking device stretching until the final position.
The command structure, as basic elements in the 32-axis motion synchronization is achieved with a central controller and four controllers by sector. Each aggregate has a mixed device input/ output digital/ analog and an inverter used to control the electric motor.
Frankfurt Commerzbank-Arena (former Waldsatdion) is one of the top 10 stadiums in Germany with a capacity of 51,500 spectators, and was completely rebuilt for the 2006 FIFA World Cup. It is also the venue of important international concerts, exhibitions and Eintracht Museum opened in 2007 inside the great stadium.