A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis...A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption ofa fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.展开更多
Insect infestation attacks in agricultural ecosystems are becoming more common because of global warming as well as farmland environmental circumstances,necessitating the development of new crop production technology....Insect infestation attacks in agricultural ecosystems are becoming more common because of global warming as well as farmland environmental circumstances,necessitating the development of new crop production technology.Pesticide application is one of the most common strategies for protecting the entire growing period of plants or shrubs against pests and pathogens in farms.The rapid,effective,and profitable application of plant control substances via unmanned aerial vehicle(UAV)crop spraying is anticipated to be a key new technique.When compared to ground spraying,UAV spraying saves chemicals,water,time,does not damage crop plants or balls of crop,and does not create soil compaction.When using UAV,pesticide drift and deposition must be managed in order to use pesticides safely,effectively,and efficiently.This paper focuses on agrochemical spraying by unmanned aerial vehicles and the key parameters that influence spray effectiveness,such as the operating parameters of nozzle type,flying speed,flight height,type of nozzle,and type of UAV model,for reducing drift and increasing application efficiency.The multirotor UAV is most suitable for spraying due to its fast operation,safety,not requiring a runway for takeoff and landing,and lower cost as compared to fixed-wing and VTOL.UAVs can also be used for crop disease identification,soil health monitoring,livestock monitoring,field mapping,etc.This paper aims to review the development of various UAV models,optimization of operating parameters,effect of nozzle on UAV spraying,characterization of droplet deposition,drift reduction technology,UAV-based remote sensing for plant protection,and cost comparison of UAV to conventional ground sprayer.展开更多
In recent times,the use of vertical take-off and landing(VTOL)multi-rotor Unmanned Aerial Vehicle(UAVs)for spraying chemical pesticides against weeds and pests has recently become popular.The current aerial spray appl...In recent times,the use of vertical take-off and landing(VTOL)multi-rotor Unmanned Aerial Vehicle(UAVs)for spraying chemical pesticides against weeds and pests has recently become popular.The current aerial spray application research is primarily focused on examining the influence of UAV spraying parameters such as flight height,travel speed,rotor configuration,droplet size,payload and wind velocity.The downwash airflow velocity generated by the UAV rotor propeller has a significant impact on the droplet deposition process.A test rig was developed to measure the downwash airflow pattern generated by the rotor propeller of a UAV.In this investigation,a six-rotor electric autonomous UAV sprayer was used to investigate the parameters and distribution laws of downwash airflow velocity.The downwash airflow velocity was measured using portable anemometers mounted on the test rig at radial positions viz.,0 m,0.5 m,1 m,1.5 m and 2 m,perpendicular to(X)and parallel to the UAV’s flight direction(Y).The experiment was conducted at three levels of hover height,viz.,1 m,2 m and 3 m(Z)and three levels of payload,viz.,0 kg,5 kg,and 10 kg.The special downwash airflow distribution pattern was analysed using the Python programming language(Version 3.7).Results show that the downwash airflow velocity generated by the radial position of the UAV rotor is evenly distributed on the rotating loop and the standard deviation of the downwash airflow velocity is less than 0.5 m/s.The maximum downwash airflow velocity of 13.8 m/s was observed below the rotor at 10 kg payload capacity,1 m hover height(Z),and 0.5 m in the X-direction.The minimum downwash wind field of 0.3 m/s was observed at 0 kg pay load capacity,1 m height,and 2 m in the X-direction.The downwash airflow velocity along each position in the radial direction of the rotor increases initially and then decreases.This downwash airflow distribution results helps in mounting of spray nozzle configuration to drone sprayer which helps to understanding spray liquid distribution and other spray operational parameters.The influence of downwash airflow distribution combined with the spray operational parameters of the UAV sprayer viz.,flight height,travel speed,rotor configuration,payload and wind velocity on spray volume distribution was studied.A field experiment was conducted to study the effect of UAV sprayer downwash airflow distribution on spray droplet deposition characteristics in a rice crop compared with manual knapsack sprayer.展开更多
基金This project is supported by National Natural Science Foundation of China (No.50675075).
文摘A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption ofa fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.
基金financially supported by the Deanship of Scientific Research,Vice Presidency for Graduate Studies and Scientific Research,King Faisal University,Saudi Arabia(Grant No.KFU243000).
文摘Insect infestation attacks in agricultural ecosystems are becoming more common because of global warming as well as farmland environmental circumstances,necessitating the development of new crop production technology.Pesticide application is one of the most common strategies for protecting the entire growing period of plants or shrubs against pests and pathogens in farms.The rapid,effective,and profitable application of plant control substances via unmanned aerial vehicle(UAV)crop spraying is anticipated to be a key new technique.When compared to ground spraying,UAV spraying saves chemicals,water,time,does not damage crop plants or balls of crop,and does not create soil compaction.When using UAV,pesticide drift and deposition must be managed in order to use pesticides safely,effectively,and efficiently.This paper focuses on agrochemical spraying by unmanned aerial vehicles and the key parameters that influence spray effectiveness,such as the operating parameters of nozzle type,flying speed,flight height,type of nozzle,and type of UAV model,for reducing drift and increasing application efficiency.The multirotor UAV is most suitable for spraying due to its fast operation,safety,not requiring a runway for takeoff and landing,and lower cost as compared to fixed-wing and VTOL.UAVs can also be used for crop disease identification,soil health monitoring,livestock monitoring,field mapping,etc.This paper aims to review the development of various UAV models,optimization of operating parameters,effect of nozzle on UAV spraying,characterization of droplet deposition,drift reduction technology,UAV-based remote sensing for plant protection,and cost comparison of UAV to conventional ground sprayer.
文摘In recent times,the use of vertical take-off and landing(VTOL)multi-rotor Unmanned Aerial Vehicle(UAVs)for spraying chemical pesticides against weeds and pests has recently become popular.The current aerial spray application research is primarily focused on examining the influence of UAV spraying parameters such as flight height,travel speed,rotor configuration,droplet size,payload and wind velocity.The downwash airflow velocity generated by the UAV rotor propeller has a significant impact on the droplet deposition process.A test rig was developed to measure the downwash airflow pattern generated by the rotor propeller of a UAV.In this investigation,a six-rotor electric autonomous UAV sprayer was used to investigate the parameters and distribution laws of downwash airflow velocity.The downwash airflow velocity was measured using portable anemometers mounted on the test rig at radial positions viz.,0 m,0.5 m,1 m,1.5 m and 2 m,perpendicular to(X)and parallel to the UAV’s flight direction(Y).The experiment was conducted at three levels of hover height,viz.,1 m,2 m and 3 m(Z)and three levels of payload,viz.,0 kg,5 kg,and 10 kg.The special downwash airflow distribution pattern was analysed using the Python programming language(Version 3.7).Results show that the downwash airflow velocity generated by the radial position of the UAV rotor is evenly distributed on the rotating loop and the standard deviation of the downwash airflow velocity is less than 0.5 m/s.The maximum downwash airflow velocity of 13.8 m/s was observed below the rotor at 10 kg payload capacity,1 m hover height(Z),and 0.5 m in the X-direction.The minimum downwash wind field of 0.3 m/s was observed at 0 kg pay load capacity,1 m height,and 2 m in the X-direction.The downwash airflow velocity along each position in the radial direction of the rotor increases initially and then decreases.This downwash airflow distribution results helps in mounting of spray nozzle configuration to drone sprayer which helps to understanding spray liquid distribution and other spray operational parameters.The influence of downwash airflow distribution combined with the spray operational parameters of the UAV sprayer viz.,flight height,travel speed,rotor configuration,payload and wind velocity on spray volume distribution was studied.A field experiment was conducted to study the effect of UAV sprayer downwash airflow distribution on spray droplet deposition characteristics in a rice crop compared with manual knapsack sprayer.
