【作者】 周海波；

【导师】 马旭；

【作者基本信息】 吉林大学 ， 农业电气化与自动化， 2009， 博士

【摘要】 本文紧密围绕国家“十一五”科技支撑计划子课题“超级稻超低播量精准育秧播种技术及装备”和国家自然科学基金资助项目“超级稻精密播种机构的基础理论与关键技术研究”等开展研究工作。结合超级稻机械化种植的农艺要求,重点从精量取种、准确播种、孔穴精密对中控制,减少空穴等关键技术方面进行深入研究,有效地解决了超级稻超低播量机械化秧盘育秧精密播种技术及装备的关键问题。采用振动原理,研制了一种电磁振动种室和气动振盘相结合的振动式精密播种装置,实现播种的精确控制;利用电磁换向和气缸限位控制,研制了一种新型气力式双层滚筒精密播种器的秧盘连续输送与穴孔同步精准播种对中的控制系统,解决了秧盘育秧精密播种同步对中的难题;应用计算机视觉检测技术,提出了钵体盘视觉检测、实施空穴补种的思路,研制了钵体盘空穴视觉检测系统。本文通过关键技术的研究与应用,为超级稻秧盘育秧精密播种机的总体配置和精确控制奠定了良好基础,设计了两种不同精度的超级稻秧盘育秧精密播种机,研制出了2CYL-450型低成本振动式水稻秧盘育秧精密播种机流水线,并对该机进行了超级稻和常规稻的现场应用试验。试验结果表明,该机满足不同水稻秧盘育秧的播种要求,性能稳定可靠。更多还原

【Abstract】 The seeding is an important step for factory tray nursing seedlings of rice. The tray nursing seedlings seeder matching with rice seedling thrower and transplanter should be developed, which is an important guarantee to realize rice planting mechanization.The rice nursing seedlings seeders have been research since the 1970s. With the development of the nursing seedlings technology, technique and automation level of the rice nursing seedlings pipeline gradually improve at home and abroad. From seeding accuracy, traditional mechanical seeder with great sowing rate is used for early conventional rice. Although this machine has many advantages such as simple structure and high efficiency, it has some damage for the seed. For hybrid rice, the vibration seeder and the vibration combined with pneumatic type seeder is adopted to realize precision seeding. At present, this kind of seeder has many disadvantages such as uneven seed, high cavities ratio and low sowing accuracy.With the constant development of new rice varieties and planting technology, original conventional rice and hybrid rice were replaced by super rice having excellent quality and high yield. Characteristics of planting technique of this rice is precision seeding, cultivating strong seedlings, wide space planting, quantitative controlling seedlings, aerobic irrigation, precision fertilization and integrated control. After having analyzing equipments for rice precision seeding of tray nursing seedlings at home and abroad, it can be conclude that available seeder is not suitable to the super rice. So technology of the rice nursing seedlings seeders must be improved.According to the main technical difficulties and some key technologies, the main contents and conclusions of the paper are following:1) By research and analysis on work principle and seeding technology about rice precision seeder at home and abroad, some key technologies in the tray nursing seedlings of super rice such as precision seeding, accuracy of throwing seeding, reducing empty hole and high efficiency need use the advanced seeding technology, control method and detection means, which can obtain better seeding property and high working reliability and improve the comprehensive technical level of the tray nursing seedlings of rice.2) Based on the vibration principle, the vibration combined with pneumatic type seeder is designed in detail, then basic theory and working performance about electromagnetic vibration supplying seed device and pneumatic vibration tray system are researched and analyzed. Prediction model of quantitative supplying seed based on the back-propagation neural networks is established and relative error of testing sample is less than 5%. The quantitative supplying seed model established is simulated, which provide the basis for choosing the working parameters of quantitative supplying seed device. The preferable parameters combination of pneumatic vibration tray system is obtained by using orthogonal test. Working performance of pneumatic vibration tray system is detected by the adjustment of pressure valve. Two motion types of rice seed in pneumatic vibration tray, namely downslide and jump, are presented based on the theoretical analysis of motion conditions. By the dropping seed speed optimization test , the effect rules of seed flow on seeding uniformity are presented and it can be concluded that ideal sowing condition could not be achieved in manner of single seed flowing. The optimum dropping seed speed should be chosen within the range of 1/1.50~1/1.40 times of single seed flowing, and then input gas pressure of air-style vibrator is obtained according to Fig. 2.25 and Fig. 2.26, which can ensure sowing qualified rate more than 85% and cavities ratio less than 3%. By theoretical analysis and experimental study on vibration precision seeder, precision seeding technology of super rice is solved in two aspects of the quantitative supplying seed and uniform seeding. The vibration precision seeder is developed, and it can satisfy various technical requirements.3) Using the magnetic directional valve and cylinder, a kind of the synchronous matching system of continuous transport tray cave and cylinder-seeder sucking hole used for the pneumatic double-drum precision seeder is developed for the first time, which achieve the cave of tray matching the hole of pneumatic cylinder-seeder in precision. Through synchrodrive calculation, synchronization transmission process between the cave of tray and the suction holes of pneumatic cylinder-seeder are finished by chain drive. Two-layer supply mechanism and synchronous matching mechanism can minimize laboring effectively and make the cave of tray match the hole of pneumatic cylinder-seeder in precision. The test results show that the qualification rate of synchronous matching mechanism is 98.2% when the productivity is 450 trays per hour. The device of continuous transport tray and cave-hole synchronous matching was developed. So a technical problem of super rice precision seeding is well solved. This system has many advantages such as simple structure, high efficiency, low cost and good working performance.4) To improve the seedlings survival rate of super rice precision seeding, seeding cavity detection in tray nursing seedlings of super rice based on computer vision technology and reseeding is put forward. The programmer is written and utilized on virtual LabVIEW software platform by using computer vision technology, and a series of functions such as acquisition and processing of sensor signal, acquisition and processing of tray image and data storage are finished. The mask images consistent with the tray seeding cavities and binary images of seeds are synthesized by using the image processing functions provided by vision module under red light R component plot. The binary mask images of seeds are established and seed gray average in mask image are obtained, which can be the base of identifying cavity. This tray detection system are set behind the seeding process and made application test. The test results show that cavity detection accuracy is more than 75% and these cavity data provide foundation for reseeding.5) The improvement-type pneumatic double-drum precision seeder used for tray nursing seedlings of rice is developed, which are configured the synchronous matching system and the seeding cavity detection technology for the first time. This machine is complete-functions, advanced technology and high seeding accuracy, but complex structure and high technologies, so it is applicable for the high precision tray nursing seedlings of super rice.6) The popular type (2CYL-450) rice nursing seedlings seeding pipeline is developed in this paper. This machine has advantages of simple structure, strong currency and easy adjustment, which is applicable when the tray hole is close to the drill. The test results show that at 2±1 seeds per hole, the sowing qualified rate is 90% and cavities ratio is 1.4% when the productivity is 450 trays per hour, which come up to the technical index of super rice nursing seedlings seeding. For the conventional rice, variation coefficient of supplying seed is less than 5%, which come up to the precision seeding at 5~8 seeds per hole, too. In a word, field application tests were conducted by the prototype in Pinghu city of Zhejiang province and state farms of Heilongjiang province. Tests result show that this prototype can satisfy the rice nursing seedlings seeding with a variety of trays and rice.更多还原