The model of spraying droplets distribution based onlaser sensors

摘要

To describe spatial distribution of spraying droplets or sprinkler droplets has been a difficulty in agriculture.However, the distribution of spray droplets or sprinkler droplets is an important index to evaluate a nozzle. At present, there is a lot of research on pesticide spraying, and these studies are mainly about droplets deposit, spray control and detection method.If using the laser detection technology properly with the appropriate post-processing software, we are likely to recover the droplets spatial distribution. According to the time of flight principle and Multi-pulse principle of laser, we can measure the specific droplets position and its velocity.By determining the detection object and spatial orientation, we can get the droplets position. By counting the position, time domain, and space area of tangent plane of the detection object, and stacking the time domain, we can get the distribution section of droplets. At last, by extracting the feature scale in different section, we can get the 3D model. With the data from the laser sensor, a program that we has compiled by the MATLAB software is used to change the format of data, generate the three-dimensional image, and calculate the spray area and velocity. The first, the data is exchanged from polar format to rectangular coordinate format. The data has two kinds: Pre-data with environment data only and Mix-data with environment data and water datamixed. The two kinds of data are superposed to eliminate and we get the Us-data later. After that, we use the Us-data to draw the images. When we get enough images, we need to engage in data analysis to get the further result. After using probability distribution and parameter estimation to describe more details of the data, we will get the parameter of speed and the parameter of area. In this way, we can describe spray droplets or sprinkler droplets easily and accurately, and at the same time, we canreduce the cost.