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Full-Text Articles in Engineering
As-Applied Estimation Of Volumetric Flow Rate From A Single Sprayer Nozzle Series Using Water-Sensitive Spray Cards, Michael P. Sama, John T. Evans, Aaron P. Turner, Surya Saket Dasika
As-Applied Estimation Of Volumetric Flow Rate From A Single Sprayer Nozzle Series Using Water-Sensitive Spray Cards, Michael P. Sama, John T. Evans, Aaron P. Turner, Surya Saket Dasika
Biosystems and Agricultural Engineering Faculty Publications
The objective of this study was to test the feasibility of using coverage measurements from water-sensitive spray cards to estimate the volumetric flow rate at an individual sprayer nozzle. TeeJet VisiFlow Even Flat Spray Tips were selected due to their uniform distribution of coverage. Spray distribution for each nozzle was validated using a spray patternator table with 2.5 cm sampling widths. A rotary test fixture translated water-sensitive spray cards through the spray dispersion (water at ambient conditions) at a constant angular velocity and a radius of 1.2 m. The test fixture measured volumetric flow and pressure at the nozzle and …
Recalibration Methodology To Compensate For Changing Fluid Properties In An Individual Nozzle Direct Injection System, Joe D. Luck, Scott A. Shearer, Brian D. Luck, Michael P. Sama
Recalibration Methodology To Compensate For Changing Fluid Properties In An Individual Nozzle Direct Injection System, Joe D. Luck, Scott A. Shearer, Brian D. Luck, Michael P. Sama
Biosystems and Agricultural Engineering Faculty Publications
Limited advancement of direct injection pesticide application systems has been made in recent years, which has hindered further commercialization of this technology. One approach to solving the lag and mixing issues typically associated with injection-based systems is high-pressure individual nozzle injection. However, accurate monitoring of the chemical concentrate flow rate can pose a challenge due to the high pressure, low flow, and changing viscosities of the fluid. A methodology was developed for recalibrating high-pressure chemical concentrate injectors to compensate for fluid property variations and evaluate the performance of this technique for operating injectors in an open-loop configuration. Specific objectives were …
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 …
Distribution Pattern Variability Of Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Dennis Wayne Hancock, Timothy S. Stombaugh
Distribution Pattern Variability Of Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Dennis Wayne Hancock, Timothy S. Stombaugh
Biosystems and Agricultural Engineering Faculty Publications
Granular applicators equipped with variable-rate technology (VRT) have gained popularity in recent years as a result of increased interest in variable-rate application. The purpose of this investigation was to characterize distribution patterns at varying rates for different granular applicators. Uniform-rate (UR) tests were conducted to assess the accuracy of variable-rate application from four granular applicators: two spinner-disc spreaders (A and B), and two pneumatic applicators (C and D). Pattern results indicated a consistent triangular pattern for spinner spreader B and consistent patterns for the pneumatic applicators (C and D). However, applicator D produced pattern variations at the center and right …
Rate Response Assessment From Various Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Matthew J. Darr, Timothy S. Stombaugh
Rate Response Assessment From Various Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Matthew J. Darr, Timothy S. Stombaugh
Biosystems and Agricultural Engineering Faculty Publications
Variable-rate technology (VRT) adds complexity to application equipment, thereby confounding the assessment of applicator performance. The intent of this investigation was to assess the rate response of various VRT granular applicators: two spinner spreaders (A and B), and two pneumatic applicators (C and D). Variable-rate (VR) tests were conducted to quantify the rate response characteristics (delay and transition times) for the applicators. A sigmoidal function was used to model the rate response for five of the six tests. Applicator A exhibited a linear response during decreasing rate changes. Results indicated that only applicator B demonstrated consistent delay and transition times, …
Crop Yield Response To Precision Deep Tillage, Larry G. Wells, Timothy S. Stombaugh, Scott A. Shearer
Crop Yield Response To Precision Deep Tillage, Larry G. Wells, Timothy S. Stombaugh, Scott A. Shearer
Biosystems and Agricultural Engineering Faculty Publications
Experimental precision deep tillage was applied at three sites in central Kentucky with relatively well-drained silt loam soils in no-till crop production. Fields were divided into 0.4 ha (1 ac) grid cells using DGPS mapping. Assessment of soil compaction by machinery traffic was made using multiple soil cone penetrometer measurements and expressed as cone index (CI). Corn, wheat, and soybean yields were depressed in grid cells with CIavg ≥ 1.5 MPa (218 psi) prior to application of tillage treatments at sites 1 and 3, whereas at site 2, where most of the highest average CI values ranged from 1.44 …
Controller Area Network Based Distributed Control For Autonomous Vehicles, Matthew J. Darr, Timothy S. Stombaugh, Scott A. Shearer
Controller Area Network Based Distributed Control For Autonomous Vehicles, Matthew J. Darr, Timothy S. Stombaugh, Scott A. Shearer
Biosystems and Agricultural Engineering Faculty Publications
The goal of this project was to evaluate the potential of a controller area network (CAN bus) to be used as the communication network for a distributed control system on an autonomous agricultural vehicle. The prototype system utilized microcontroller-driven nodes to act as control points along a CAN bus. Messages were transferred to the steering, transmission, and hitch control nodes via a task computer. The task computer utilized global positioning system data to generate appropriate control commands. Laboratory and field testing demonstrated that each of the control nodes could function simultaneously over the CAN bus. Results showed that the task …
Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins
Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins
Biosystems and Agricultural Engineering Faculty Publications
Research has shown that application errors exist with variable–rate technology (VRT) systems. Consequently, using prescription maps for economic and agronomic analyses can generate misleading results. The intent of this article was to develop and validate a spatial data model for generating “as–applied” maps to support the advancement of precision agriculture practices. Previous research modified ASAE Standard S341.2 to include a 2–D matrix of collection pans to assess fixed–rate and variable–rate (VR) deposition of granular fertilizers and agricultural lime from a spinner disc spreader. The “as–applied” spatial data model uses GIS functionality to generate “as–applied” surfaces by merging distribution patterns and …