Starbugs: all-singing, all-dancing fibre positioning robots

摘要

Starbugs are miniature piezoelectric 'walking' robots with the ability to simultaneously position many optical fibresacross a telescope's focal plane. Their simple design incorporates two piezoceramic tubes to form a pair of concentric'legs' capable of taking individual steps of a few microns, yet with the capacity to move a payload several millimetresper second. The Australian Astronomical Observatory has developed this technology to enable fast and accurate fieldreconfigurations without the inherent limitations of more traditional positioning techniques, such as the 'pick and place'robotic arm. We report on our recent successes in demonstrating Starbug technology, driven principally by R&D effortsfor the planned MANIFEST (many instrument fibre-system) facility for the Giant Magellan Telescope. Significantperformance gains have resulted from improvements to the Starbug system, including i) the use of a vacuum to attachStarbugs to the underside of a transparent field plate, ii) optimisation of the control electronics, iii) a simplifiedmechanical design with high sensitivity piezo actuators, and iv) the construction of a dedicated laboratory 'test rig'. Amethod of reliably rotating Starbugs in steps of several arcminutes has also been devised, which integrates with the pre-existingx-y movement directions and offers greater flexibility while positioning. We present measured performance datafrom a prototype system of 10 Starbugs under full (closed-loop) control, at field plate angles of 0-90 degrees.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.