Development of a PWM Precision Spraying Controller for Unmanned Aerial Vehicles

ThispaperpresentsanewPulseWidthModulation(PWM)controllerforUnmannedAerialVehicle(UAV)precisionsprayerforagricultureusingaTL494fixed-frequencypulsewidthmodulatortogetherwithadataacquisitionboardanddevelopedsoftware.AnUAVcanberemotelycontrolledorflownautonomouslybypre-programmedflightplans.ThePWMcontrollerwasimplementedthroughtheguidancesystemontheUAVwithcontrolcommandssentbetweentheUAVhelicopterandthegroundcontrolstationviaawirelesstelemetrysystem.ThePWMcontrollerwastestedandvalidatedusingLabVIEW8.2.Severalanalyseswereperformedinalaboratorytotestdifferentcontrolsignals.TheresultsshowthatthePWMcontrollerhaspromiseasahigherprecisiontechniqueforsprayapplications,whichwillimproveefficiencyofpesticideapplication,especiallyincropproductionareas.