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Full-Text Articles in Controls and Control Theory
Control System Development And Response Analysis Of An Electronically Actuated Variable-Orifice Nozzle For Agricultural Pesticide Applications, Joe D. Luck, Scott A. Shearer, Michael P. Sama, Santosh K. Pitla
Control System Development And Response Analysis Of An Electronically Actuated Variable-Orifice Nozzle For Agricultural Pesticide Applications, Joe D. Luck, Scott A. Shearer, Michael P. Sama, Santosh K. Pitla
Biosystems and Agricultural Engineering Faculty Publications
The goal of this research project was to further the development of an electromechanically controlled variable-orifice nozzle by creating an electronic control system and then evaluating that system based on step and ramp inputs. The control system was developed in a programming environment that combined an electronic data acquisition system and actuator with pressure and flow sensors. A proportional, variable-gain (based on system pressure) control system was developed to adjust nozzle flow rates to meet target application rates. The constraints were to achieve settling time of less than 1.0 s, overshoot of less than 10% of maximum flow (or minimum …
Flow, Spray Pattern, And Droplet Spectra Characteristics Of An Electronically Actuated Variable-Orifice Nozzle, Joe D. Luck, Santosh K. Pitla, Michael P. Sama, Scott A. Shearer
Flow, Spray Pattern, And Droplet Spectra Characteristics Of An Electronically Actuated Variable-Orifice Nozzle, Joe D. Luck, Santosh K. Pitla, Michael P. Sama, Scott A. Shearer
Biosystems and Agricultural Engineering Faculty Publications
The purpose of this study was to develop and evaluate the flow rate, spray pattern, and droplet spectra characteristics of an actively controlled variable-orifice nozzle at constant carrier pressures. A commercially available variable-orifice nozzle (VariTarget) was modified to allow for direct electromechanical control of the metering stem. The modified system was tested at five carrier pressures ranging from 138 to 414 kPa and five metering stem (and thus orifice) positions. The metering stem position range was chosen because it provided a linear response in flow rate at each carrier pressure. Flow rate testing indicated a turndown ratio of 2.4:1 at …