SUBARU top unit exchanger

The SUBARU Telescope has four focal positions to allow different types of instruments. At present, there are four different Top Units; three types of secondary mirrors and one primary focus unit. These units have the weight of about 3 tons, and they need to be installed or changed high above in the air, with the telescope in its rest position, namely, pointed to the zenith. In order to carry out this exchange work safely and securely, in already a difficult working condition of high altitude place like Mauna Kea, we developed an automatic exchanger with remote control, called Top Unit Exchanger (TUE).