The Max-Planck-Institute for Biochemistry and Neurobiology in Martinsried, south-west of Munich, required a cafeteria for employees and guests close to the main entrance of the existing concrete building from the 1970s. It is accommodated in a small atrium canopied by a glass dome, which can be opened up completely by a sliding mechanism. The structure of the continuously adjustable mobile roof consists of a rigid frame with dimensions of 12 m x 12 m. Inserted into this frame is a mesh structure of box sections. The mesh structure has been generated as translation surface of identical circle segments. Whereas, all bar lengths are equal and equal rectangles determine the shape of the mesh structure. Thus, the panes are attached directly to the structure, rendering a sub-construction unnecessary. To prevent most of the statically unfavourable lateral forces the double-curved dome surface transfers the load mainly via compression forces. The cross sections of the steel profiles are minimised to 50 x 40 mm in a grid of 1.65 m x 1.65 m. Two directly driven maintainance-free wheel blocks enable the operation of the roof.