Abstract: The change in spray pressure causes the change in spray flow rate and finally affects the uniformity of the spray. In this paper，the real- time nozzle tip pressure controlled by the independent nozzle of the boom sprayer was taken as the research object，the independent nozzle control system and nozzle tip pressure data acquisition system were built based on the C37 controller. The pressure dynamics of the nozzle tip when 5，10，or 15 nozzles were opened and closed at the same time were collected，and the pressure dynamic characteristics were analyzed. The real- time pressure dynamic test results of independent nozzle control showed that the number of nozzle openings and closings had a significant influence on the nozzle tip pressure. The opening position of the nozzle had no significant influence on the pressure change of the nozzle tip，and the pressure changes of the nozzle tip collected by all pressure sensors were consistent. At the same time，in the process of opening and closing 5，10，or 15 solenoid valves，the pressure at the nozzle tip varied during 6. 0% and 20. 0%，and the spray flow rate varied during 3. 20% and 10. 90%. Using the independent nozzle control system and nozzle tip pressure data acquisition system built in this paper，the real- time pressure dynamics of independent nozzle control of boom sprayers were obtained，which provided a reference for spray uniformity research of independent nozzle control boom sprayers on a farm and the research of the target spray technology.

Key words: boom sprayer, spray pressure, tip pressure, independent nozzle control