农业工程学报2017，Vol.33Issue(15)：72-80,9.DOI:10.11975/j.issn.1002-6819.2017.15.009
靶向灭草机器人药液喷洒空气动力学模型建立与验证
Aerodynamics modeling and validation on liquid medicine spraying of target weeding robot
摘要
Abstract
Field weeds have a great effect on the yield of normal economic crops. The commonly used methods of weeding include artificial weeding, mechanical weeding, weed quarantine, biological control, chemical control, and so on. Among those methods, chemical weeding is the best when it comes to sudden grass damage (the weeds of disaster break out suddenly), because it works well and takes less time. However, when we use chemical weeding, there are many problems such as low utilization rate of liquid medicine and serious pollution to the environment with overplus liquid. Therefore, toward-target pesticide application is proposed to solve these problems above all. As we all know, toward-target pesticide application machineries often use machine vision technology to obtain spatial location information of weeds, which makes the nozzle rigidly fixed on the machine and at the same time, the control system adjusts the valve to open and close to achieve the purpose of spraying. On this basis, we use spraying nozzle to change the direction of application, resulting in precision spraying in this paper. In order to study the law of motion for spray droplet, we established dynamic model based on application methods with the principle of aerodynamics, and then the formula of the droplet flying and the analytic formula of the falling point were deduced. Next, the numerical simulation analysis of the covering area was carried out. Especially, in the process of analysis, we discussed the resistance characteristics of spray droplets, the nozzle angle, nozzle speed, machine speed and injection pressure, which affect the movement process we discussed. What's more, the model established above can also be used to control the location and shape of the droplet cover area by adjusting the working parameters, to improve the accuracy of toward-target pesticide application. Furthermore, in order to verify the correctness of the model, we set up the toward-target pesticide application platform and selected the special test site. Under no wind conditions, we conducted a simple target spraying test indoor, and then measured the geometric characteristics of actual liquid dripping place carefully. At the same time, the relevant parameters were obtained by high-speed camera technology. Next, we took the data into the dynamic model mentioned above to get the theoretical coverage of the liquid medicine, which was then compared with the actual coverage of the liquid medicine. Finally, it can be found that there is an error between the calculated and experimental results, and the error range is 8%-13%. In addition, to study the sedimentary characteristics of liquid medicine with this application method, we analysed the distribution law of the deposition amount of liquid medicine in the effective coverage area by water absorption paper weighing method. According to the analysis, it can be seen that the peak value of sediment changes regularly with the parameters such as the change of the nozzle angle, which suggests that the physical background of the model is clear, and the correlation between the parameters of the model and the sprinkler type is small, so the model transplant is strong. In other words, it can be used as a theoretical basis for the relevant spraying machinery.关键词
机器人/模型/计算机仿真/对靶施药/药液覆盖区Key words
robots/models/computer simulation/targeted weeding/liquid covering area分类
农业科技引用本文复制引用
权龙哲,王建森,奚德君,郦亚军,孙文峰,陈词..靶向灭草机器人药液喷洒空气动力学模型建立与验证[J].农业工程学报,2017,33(15):72-80,9.基金项目
国家自然科学基金资助项目(51405078) （51405078）
黑龙江省博士后基金( LBH-Z13022 ) （ LBH-Z13022 ）
黑龙江省普通高等学校青年创新人才培养计划(LR-356214) （LR-356214）
东北农业大学"青年才俊"项目(518020) （518020）
