×

Evapotranspiration forecasting irrigation control system

  • US 5,696,671 A
  • Filed: 01/06/1997
  • Issued: 12/09/1997
  • Est. Priority Date: 02/17/1994
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for efficiently controlling irrigation, including the steps of:

  • (a) determining evapotranspiration data characteristics of an irrigation site;

    (b) determining forecast meteorological data, including expected precipitation, for the irrigation site based on current meteorological conditions;

    (c) forecasting an ETo value, ETo'"'"', from the forecast meteorological data;

    (d) calculating a current soil moisture depletion value Cdt for the irrigation site as proportional to a previous soil moisture depletion value Cdt-1 for the irrigation site plus a daily depletion value Dd that depends upon the evapotranspiration data characteristics of the irrigation site, less an effective expected precipitation value, Peff, determined from the forecast meteorological data;

    (e) electronically computing a watering schedule based upon at least the current soil moisture depletion value Cdt ; and

    (f) applying the computed watering schedule to at least one irrigation control system to control at least one irrigation valve of such control system in accordance with such watering schedule, wherein the computed watering schedule controls when and how much to irrigate through each irrigation valve.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×