Described herein are several embodiments relating to modular irrigation controllers. The apparatus has multiple embodiments and useful applications, in that it can be attached to a vehicle’s hitch receiver, or can be self-supporting utilizing fold-out stabilizing or attachable legs, for example. The dimension in the direction of gate length of the second gate electrode layer, which is formed on the first gate electrode layer, is smaller than the dimension in the direction of gate length of the first gate electrode layer. The use of a fuzzy logic algorithm creates a more useful result as the classifier results are not merely averaged.