Application of Herbicides by Direct Injection for Site - Specific Spraying

Abstract

A laboratory model for an direct injection system was designed for the metering of appropriate herbicide into a carrier close to the nozzles. Two experiments were performed to investigate the dynamic behavior of this system. In the first experiment the position of the injection point was the center of a boom section and in the second experiment the chemical ingredient was injected close the nozzle. For these experiments a laboratory model of an injection sprayer system was employed. The concentration of metered chemical ingredient was measured down-stream of the injection point using a conductivity sensor based on sensing the electrical conductivity of a salt solution. This sensor was developed for the evaluation of the system time response characteristic of the sprayer. The direct nozzle injection assembly provided a minimal response time from injection point to nozzle tip with less than 2.8 s. The injection applied to a boom section caused response time with a maximum of 7.5 s. This implies a maximum position error of 6.8 to 16.7 m at 8 km h-1 forward speed of the sprayer with camera system for weed detection.

Labaratorijski model dirketnog injektorskog sistema je razvijen u smislu odgovarajuće aplikacije herbicida u blizini radnog rasprkivača. Dva eksperimenta su izvedena u cilju istraživanja dinamike ovog sistema. U prvom, pozicija injekcione tačke je bila centar krila prskalice a u drugom hemikalija je injektirana u blizini rasprskivača. U svrhu ovog eksperimenta, labaratorisjki model injektorskog uređaja je upotrebljen. Koncentracija aktivne supstance je merena ispod struje injekcione tačke upotrebom konduktivnog senzora baziranog na električnoj provodljivosti slanog rastvora. Ovaj senzora je razvijen za procenu vremena odgovora sistema prskalice. Uređaj za direktno injektiranje pokazuje minimalno vreme reakcije od injekcione tačke do vrha rasprskivača, manje od 2.8 s. Injektiranje primenjeno na sekcijama krila pokazalo je reaktivno vreme maksimalno do 7.5 s. Ovo implicira maksimalnu pozicionu grešku od 6.8 do 16.7 m pri 8 km/h brzine prskalice sa detekcionim sistemom korova snimanjem kamerom.