Starbugs

Abstract

Several facilities across the globe are conducting large spectroscopic surveys of the sky, recording the optical spectrum of millions of individual stars and galaxies, building huge databases for the next era of astronomical research. The maximum displacement achieved by each actuator is on the order of 20 pm, meaning that a single Starbug step is of a similar magnitude. At a nominal stepping frequency of 100 Hz, this translates to a speed of 2 mmls. A force is required to hold Starbugs against the surface on which they move. If the surface is magnetic, then this can be achieved by placing a magnet within or around the Starbug. If the surface is not magnetic, then a vacuum is used to provide the attractive force. The vacuum is created in the volume between the Starbug's two piezo tubes, which is connected to an evacuated chamber with a thin hose. Show more