1. A computer implemented method for selecting a controller from a plurality of controllers and constructing so that it can automate one or more processes used in a plant, comprising the steps of: constructing a controller from a plant described by an LPV model to which a scheduling parameter is given by: a) calculating via a processor one or more v gaps respectively for Min, Max, and a mean value of each candidate of a plant parameter vector of said LPV model based on a requirement of preselected constraints; b) said processor choosing a candidate via information gathered by proof said plant parameter vector based on the magnitude of differences between said v gaps; c) said processor converting the LPV model into LMI and finding controllers, according to an H ∞ criterion, at all combination end points of a maximum value and a minimum value of the plant parameter vector thus chosen; and d) said processor choosing and constructing said chosen controller for said plant by using bilinear interpolation weighted by said v gaps specifically calculated for said plant parameter vector thus chosen.