Research On Sowing Quantity Control Device Based On MCU

Seeding operations is the most basic and important aspect of modern agricultural production, the implementation of this part of the main equipment is drill, whose performance is directly related to the quality of crop sowing operations and late crops. As key components of the seed drill, so its performance is good or bad directly determines the metering uniformity. In agricultural production the seeding rate is a key factor affecting crop yields. Therefore, in order to control the planter seeding rate, access to large amounts of information and analysis on the basis of the contrast at home and abroad planter metering systems, research and design based on single-chip control stepper motor speed, to achieve the sowing rate automatically adjust control devices.The device is on the basis of the original seeder, drill gear to improve. The measurement device is a microcontroller as the core, through the establishment of the mathematical model of tractor road speed stepper motor speed to achieve the purpose of the moving speed of the tractor to control the stepper motor speed to achieve that control of the drill seeding rate. The device also used the LCD device, the C programming language to achieve a tractor road speed, real-time displayed of sowing rate and acreage.The mainly work done in this design were:(1) Completed the design of automatic control devices of the hardware system. Hall sensor was used as speed measuring device, In the regular time, the number of magnets installed on a tractor driving wheel was recorded, processed by single-chip to achieve the purpose for measuring the speed of tractor road. Microcontroller to receive the data processing, and then the control signal was sent to the stepper motor drive to control the rotation of the stepper motor. The stepper motor driven gear row kinds of shaft rotation, thus achieving the purpose of control of the planter seeding rate, and improve the uniformity of sowing.(2) After achieving hardware system design, founded the dynamic relationship between tractor road speed and the stepper motor speed, and completed the entire software design of the automatic control device. (3) The completed a software program was written to the control device in the " laboratory simulation experiment to observe the operation of the device, whether the purpose of the initial experimental design was tested.(4) The control devices was installed in the tractor and planter, and started the control device, so that the tractor at a constant speed to observe the effect of the actual operation of the control device, and adjust it to achieve the best results.(5) Putted wheat seed into the seed box, setted test conditions, started the tractor at a constant speed, and opened the multicast flow control device to achieve calibration test, the correction of the parameters of the sowing rate was completed.(6) Setted test conditions for seeding experiments again, recorded and analyzed related data.(7) Through the analysis and processing of test data, obtained the device design deficiencies and improvements, ultimately, to draw relevant conclusions.Through a series of experiments showed that the seeding rate control device according to the tractor operating speed, real-time adjustment row exclusive speed to overcome the traditional driving method due to wheel slip and drive disharmony caused leakage by ultra-broadcast-uneven seeding phenomenon. Through the analysis of experimental data, that there are differences between each row of kinds of devices. And by calculating, come to the moving speed of the tractor is to change the conclusions of the impact of broadcast. Although the device is in the seeding experiments, due to factors such as equipment and man-made some errors, but also some of the inadequacies of the need to improve. Relative to the improvement of the planter before the seeding effect has basically reached the initial design requirements, as opposed to the traditional sowing methods of precision sowing.