The European Extremely Large Telescope (ELT) Primary Mirror (M1) is a 39-m diameter mirror, compound of 798 segments. Individual Segment Assemblies need to be periodically extracted and re-integrated for off-line replacement of their reflective coating. Such replacement and alignment operation are to be performed at a rate of two segments per day. The Segment Manipulator is the handling tool allowing ELT M1 Segment Assemblies to be exchanged in-situ as part of routine ELT Telescope operations. It also enables the handling and positioning of associated generic payloads over the ELT M1. It includes as well, a permanent, general purpose long travel crane enabling the handling of equipment in and out of the ELT M1 Cell. In order to extract a segment from M1, the Segment Manipulator grabs the Segment Assembly by an interface based on 3 points at 120 deg located at its optomechanical support. To allow this operation the Segment Assembly has been moved up some centimeters from its nominal position in M1 by a dedicated Segment Extractor. Once the Segment Assembly is grabbed by the Segment Manipulator, it is moved out of M1 by the M1 Segment Crane and transferred to the unloading area, on the telescope Azimuth Floor, by the long vertical travel function provided by the Segment Manipulator. The system integrates different technologies (optics, vision, electronics, control, mechanics), facing several technological challenges, related to high seismic load, reduced mass budget and high ratio payload mass versus mass budget.
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