A Fiber Positioner Robot for the Gran Telescopio Canarias
  Fiber-fed spectrographs dedicated to observing massive portions of the sky
are increasingly being more demanded within the astronomical community. For all
the fiber-fed instruments, the primordial and common problem is the positioning
of the fiber ends, which must match the position of the objects of a target
field on the sky. Amongst the different approaches found in the state of the
art, actuator arrays are one of the best. Indeed, an actuator array is able to
position all the fiber heads simultaneously, thus making the reconfiguration
time extremely short and the instrument efficiency high. The SIDE group (see
http://side.iaa.es) at the Instituto de Astrof\'isica de Andaluc\'ia, together
with the industrial company AVS and the University of Barcelona, has been
developing an actuator suitable for a large and scalable array. A real-scale
prototype has been built and tested in order to validate its innovative design
concept, as well as to verify the fulfillment of the mechanical requirements.
The present article describes both the concept design and the test procedures
and conditions. The main results are shown and a full justification of the
validity of the proposed concept is provided.
