  We report on transport operations with linear crystals of 40Ca+ ions by
applying complex electric time-dependent potentials. For their control we use
the information obtained from the ions' fluorescence. We demonstrate that by
means of this feedback technique, we can transport a predefined number of ions
and also split and unify ion crystals. The feedback control allows for a robust
scheme, compensating for experimental errors as it does not rely on a precisely
known electrical modeling of the electric potentials in the ion trap
beforehand. Our method allows us to generate a self-learning voltage ramp for
the required process. With an experimental demonstration of a transport with
more than 99.8 % success probability, this technique may facilitate the
operation of a future ion based quantum processor.
