Hoverboards: Smart focal plane positioners for adaptive optics ELTs

The ability to simultaneously position 'large' payloads over the focal surface overcomes some of the potential barriers faced by ELTs in implementing multi-object adaptive optics. The Australian Astronomical Observatory is prototyping a new positioner capable of moving larger payloads than a typical Starbug (fiber positioners proposed for GMT). These devices, called Hoverboards, are currently capable of positioning payloads up to 3 kg over the focal surface. Hoverboards are platforms that utilize air pressure and vacuum forces to reposition with either two or more Starbugs, amplified piezo-actuators or stepper motors. Hoverboards facilitate fast field configuration times with simultaneous positioning and best utilization of the focal-plane with diversified payloads enabling multi-object surveys. Hoverboards could conceptually position compact deformable mirrors over the focal surface for implementing multi-object adaptive optics or as an imager for ground-layer adaptive optics. We report on the development of a low-cost Hoverboards prototype suitable for flat and curved focal-plane surfaces for the GMT and E-ELT.