Research On The Motion Law Of Maize Plant In Corn Stalk Chopper

Conservation tillage is a new farming technique relative to traditional plowing technique. Maize plant chopping coverage technology is a core technology of conservation tillage. The traditional maize straw chopped maize plants plucked by field straw chopper, then the strike poles were threw into field and were returned by embedding into soil. Maize plant chopping coverage technology chopped maize plants and threw the strike poles into field by shredding mechanism of maize plant. But the wheat fields covering by the strike poles could appear some problems, for example, low emergence rate, weak seedling, dead seedling, chopping coverage effect was affected. In order to solve these negative effects, we have to study the motion law of maize plant in process of chopping first.Based on these problems and the actual situations of maize plant chopping coverage, the motion law of maize plant in process of chopping was studied, the theoretical guidance of research and development of shredding mechanism was provided.The problems of low emergence rate and difficult subsequent job caused by chopping coverage were solved. Technical support of further extension conservation tillage technology was provided. The major research results included:1. Mathematical model of moving blades motion situation was established by theoretical analysis of moving blades. The rotational speed of moving blades and the forward speed of shredding mechanism were determined. The theoretical value of chopping length of maize plants was obtained combining with the motion situation of snapping roll.2. Three main influencing factors of chopping effect of maize plants, feeding distance position, forward speed, rotational speed of cutter head, were selected. The better working parameters of each influencing factor were determined preliminarily by single factor experiment. The regression model of forward speed corresponded to chopping qualified rate was established, and the regression model of rotational speed of cutter head corresponded to chopping qualified rate was established. The rationality of rotational speed of moving blades and forward speed of shredding mechanism in process of designing was validated. The better levels of each influencing factor were determined by orthogonal test, which laid a foundation of the study of maize plant motion law.3. General test stand based on high speed photography was built simulating the environment of maize plant chopping coverage. The test stand mainly included feeding system of maize plant, high speed photography system, corn harvest header and whole control system. The test stand could realize speed feeding, speed chopping, motion image real time recording, working parameter automatic collecting. The test stand was safe and reliable, facilitated the operation, was the effective means and tool for maize plant motion law research.4. The imaging principle of high speed camera was researched. The calibration principle was analyzed mainly. Three coordinate systems were studied and the transformation relation was described with mathematical language. The motion image preprocessing technology of maize plant was researched, and the threshold segmentation technology was analyzed mainly.5. The chopping motion images of maize plants were traced and recorded by using high speed photography under the conditions of better levels of each influencing factor of maize plant chopping effect. The chopping process was mainly divided into three stages. They were instant of contacting with cutter head, process of chopping and after chopping. The motion images of each stage were treated and analyzed. Three main motion parameters of maize plants, displacement, velocity and acceleration were researched and the regression models of each parameter were obtained.