Method and system for active flow rate and droplet size control of variable-orifice spray nozzle

A method for controlling a variable-orifice spray nozzle system having a plurality of variable-orifice spray nozzles, the method comprising:

• upon startup, sending a control signal to the plurality of variable-orifice spray nozzles to set an actuator that sets and changes the position of an orifice control mechanism in each nozzle to a home position;
• determining a position of the actuator and a fluid pressure level to achieve a desired nozzle flow rate and droplet size;
• setting the fluid pressure level;
• controlling the actuator to set the position via open loop control that controller commands step movement and direction of the actuator and tracks the actuator position by counting motor steps relative to the home position.

An agricultural spray system, comprising:

• a plurality of variable-orifice spray nozzles spaced apart on a spray boom, each of the plurality of variable-orifice spray nozzles including a nozzle body having a flexible nozzle orifice opening and a mechanism that physically changes the size and shape of the flexible nozzle orifice opening, an actuator to set and change the position of the orifice control mechanism, and a mount to attach to a spray boom, wherein the actuator has a home position;
• a pressure sensor to sense fluid pressure delivered to the nozzle body;
• a controller to control the actuator to set a requested nozzle flow rate and/or droplet size based upon data from the pressure sensor via positioning of the actuator, wherein the controller tracks the actuator position relative to its home position via open loop control;
• and
• a weather control system including one or more sensors, the weather control system being configured to adjust the requested nozzle flow rate and/or droplet size of the controller according to sensed weather conditions of the one or more sensors.