Design And Experiments On Boom Height Automatic Adjusting System

The low effective utilization rate of pesticide and agricultural products pesticide residuesexceeding are outstanding. The main reason is the backward spraying process and sprayingequipment. Extremely backward Plant Protection Machinery and the rapid development ofpesticide levels are extremely unbalanced, and this phenomenon is seriously hampering theeffective control of crop pests, causing undue loss and adverse consequences.Boom sprayer is the most widely used models in field, because of the advantages ofefficient, fast, controllable and automation advantages. How to reduce pesticide losses andimprove the utilization of pesticides, reduce pesticide residues and protect the ecologicalenvironment has become a hot research. Many studies have shown harmful vibration boommotion have a very significant impact on the boom sprayer spraying uniformity, andimproving boom sprayer spray uniformity become one of the core issues of plant protectionresearch workers. Therefore, the design of boom height automatic adjusting system is veryimportant quality for adjusting spray boom position real-time and improving the quality ofpesticide spraying. In this paper, for the problems of boom sprayer, design a system toautomatically adjust the height of boom and make a test of spray distribution. The mainsubjects and conclusions of the research were as follows:（1）Based on Solidworks the mechanical structure of boom height adjustment systemwas designed and virtual assembled. The mechanical system includes the boom suspensionmechanism; boom folding mechanism; boom height adjusting mechanism and other parts.Using three-dimensional software optimize design the agencies, and get a reasonable boomheight adjustment system. After experiments it shows that the normal movement ofmechanical system that meet the requirements of the intended target.（2）According to the functional requirements of boom height adjusting, boom heightdetection device was designed. And it can achieve to detect the boom height in the process ofspraying operations real-time.（3）According to the functional requirements of boom fording; boom expanding andboom height automatic adjusting, the hydraulic control circuit was designed. And tests showed that the hydraulic system can meet the job requirements.（4）The automatic controller with the core of Siemens PLC was designed, in order toachieve boom height adjustment automatic control. Tests shows that the delay time of controlsystem is1s, the boom can smoothly be maintained at the height of45cm-53.3cm, and whenthe sprayer is not greater than the running speed of4.02km/h, the height of boom heightcontrol system can achieve a good spray automatic control.（5）Make a test of spray distribution and Using bosses road simulated sprayer tiltedconditions in the field. Experimental results show that the spray distribution coefficient ofvariation of tilted boom is about30%, while the spray distribution coefficient of variationwith automatically adjust boom remained at around10%. Tests verified that the automaticboom height control system can complete the intended function.