THE AMiBA HEXAPOD TELESCOPE MOUNT

Abstract

AMiBA is the largest hexapod astronomical telescope in current operation. We\npresent a description of this novel hexapod mount with its main mechanical\ncomponents -- the support cone, universal joints, jack screws, and platform --\nand outline the control system with the pointing model and the operating modes\nthat are supported. The AMiBA hexapod mount performance is verified based on\noptical pointing tests and platform photogrammetry measurements. The\nphotogrammetry results show that the deformations in the inner part of the\nplatform are less than 120 micron rms. This is negligible for optical pointing\ncorrections, radio alignment and radio phase errors for the currently\noperational 7-element compact configuration. The optical pointing error in\nazimuth and elevation is successively reduced by a series of corrections to\nabout 0.4 arcmin rms which meets our goal for the 7-element target\nspecifications.\n