We present an investigation on a few different types of double stars which, when observed by the Hipparcos satellite, will probably produce anomalous signals. Specifically, for these objects the automatic data reduction chain set up by the FAST Consortium will usually give inconsistent results. Thus, some new mathematical models have been considered in order to obtain reliable parameters of such anomalous pairs, quite interesting from the astrophysical point of view. Those models are based on an attempt to systematically classify which systems are to be considered peculiar within the Hipparcos mission. As recognized in the past, among those double stars giving anomalous signals we find pairs with fast relative motion (rectilinear, parallactic and orbital), doubles with variable components, and multiple stars.