Three axis rotational flexure joints of high axial stiffness

The mechanisms for mirror positioning in synchrotron radiation beamlines at BESSY have been shown to have unique stability, precision, and reproducibility. For these mechanisms play-free flexure joints are used exclusively. The elastic material for these joints needs to have a low stiffness against bending and torsion and a high stiffness in the axial direction. It should allow a large number of moving cycles and must not fracture spontaneously. Fiber materials and especially stainless steel rope segments of small length accomplish these requirements. The paper describes a patented (Patent DE10042801.0) arrangement and is intended to provide useful information as an aid in applying this design to other mechanisms.