Application of fuzzy logic in an irrigation control system

As the soil moisture sensor of the irrigation control system has a nonlinear response and a significant time delay, it may take a considerable amount of man power to get satisfactory results by using a traditional feedback control method. On the other hand, an experienced human operator can often manage the irrigation system proficiently by simply using fingers as the sensors to decide the timing for irrigation. Since fuzzy logic has the ability to mimic human being in reasoning, it is a good alternative for the traditional control method in this case. Fuzzy control rules are either synthesized through a careful analysis of the nature of the irrigation system or automatically generated during the control process. They can determine when and for how long the plants must be watered. Two sensing mechanisms are used in the system to monitor soil moisture and detect water drainage, respectively, The effectiveness of the fuzzy control system has been verified through experiments both in laboratory and greenhouse