Retractable roof structures

This paper presents a new concept for retractable roof structures. The new structures consist of a foldable lattice of beams connected by cylindrical joints, to which covering panels or membranes are attached. These structure s fold towards their perimeter and there is practically no limit to their s hape. Solutions to the key problems that have to be solved in the course of the kinematic design of this new type of structure are presented, includin g two different ways of connecting them to fixed foundation points while ma intaining their internal degree of mobility, and how to determine the shape s of the covering panels to avoid interference during retraction.