Fecha de publicación: 12/04/2017 Fuente: Wipo "precision agriculture" The utility model discloses a variable automatic control system that gives medicine to poor free of charge based on big dipper satellite, including big dipper module of satellite position, spouting medicine device and controlling means, big dipper module of satellite position treats operation farmland position through big dipper satellite and advances line location to to fix a position information transmission and give the controller, make the controller according to geographic information from storage module transfer to should the farmland spout the anagraph case, through output module controlled pressure pump and control flap, come the control to spout the dose of medicine, controlling means's time block starts, counting time to the back controller once more follow big dipper module of satellite position acquire the locating information, then transferring the scheme of giving medicine to the poor free of charge, thus this system implementation the variable purpose of giving medicine to the poor free of charge. Controlling means's is visible nearly infrared sensor can also gather the sick worm information in field to with information transmission to controller, the controller removes to adjust the formulation rate according to this information, has further reached the purpose that the variable was given medicine to the poor free of charge. Consequently the utility model discloses a system has reached the purpose that the variable was given medicine to the poor free of charge, makes crops obtain the sick worm of proper amount liquid medicine control.