【作者】 胡振方；

【导师】 何雄奎；

【作者基本信息】 中国农业大学 ， 农业机械化工程， 2014， 博士

【摘要】 华北平原春季降水量小,蒸发量大,冬小麦生长期易发生水分亏缺。尤其华北平原本身缺水严重,传统的漫灌方式更加浪费了宝贵的水资源,因此该地区宜发展高产高效的节水农业。虽然大型灌溉机械节水节能效果较好,但是华北平原耕地不统一,水管理较分散,一家一户的耕地面积小,而且大型灌溉机械成本较高,推广难度较大,长期以来该地区的灌溉作业机械化程度较低。使用灌溉机械能够在提高作业效率的同时,减轻劳动量,节约水资源,因而轻小型灌溉机械更适合当地现状,更具有推广使用的价值。本文设计了一种全新的自走式实时变量灌溉机械,与卷盘机相配合,使用低压软管出流的方式完成矩形小地块的精准灌溉。该机器灌溉前,采用遥控控制直流电机作为灌溉机的动力源,向外牵引卷盘机PE软管；灌溉时依靠压力水驱动卷盘机内水涡轮旋转牵引灌溉机回收,依据热红外成像技术获取处方图和灌溉控制系统的指令,能够在冬小麦地进行实时变量灌溉作业,通过PE软管的一拉一收完成边走边灌溉的任务,“直来直去”的灌溉方式能够提高灌溉作业效率,节水节能。本文主要完成了以下的工作：1.完成了基于热红外成像技术的自走式实时变量灌溉机的整机设计,测试了灌溉机的工作性能,灌溉机行走速度变化率为28.6%,行走方向上基本能保持匀速运动,保证灌溉水分布均匀性；12支管流量的克里斯琴森均匀系数(CU)达到了98.91%,灌溉量能够在10mm-80mm范围内调节,满足冬小麦灌溉定额的要求。实际作业时可以通过调节不同的入口压力和作业速度,调整所需灌溉强度。2.使用VB语言编写了基于GPS的实时变量灌溉控制系统软件,并使用Protel设计了单片机控制系统电路,烧制了单片机控制程序,印制了控制器电路板,完成整个控制系统软硬件的设计。根据热红外成像技术获取的处方图,结合GPS位置信息,当灌溉机到达指定位置即可按不同需水量控制预设电磁阀组的开闭,进行实时变量灌溉。3.在2011-2012以及2012-2013两个冬小麦生长季,于中国农业大学河北吴桥实验站,分别以不灌溉和漫灌为对照,使用喷灌,滴灌,以及机械灌溉的方式进行了冬小麦大田灌溉试验,验证了自走式变量灌溉机械的可行性。总体上来说,通过设计合理的灌溉方案,使用灌溉机进行精准灌溉能够保证冬小麦的产量及产量构成的因素,株高,穗长,生物量及收获指数维持在正常的水平,与滴灌在灌溉量相差不大时,产量能够提高3.25%,水分利用效率提高了10.1%,整体作业效果良好。4.引入了基于热红外成像技术的水分胁迫指数(CWSI)作为评价灌溉效果的指标,通过提前预测冬小麦产量评价实际灌溉效果,验证了使用热红外成像技术获取CWSI的方法的可行性及产量和CWSI较强的负相关关系,结合BP神经网络的方法对冬小麦产量进行了预测,相比于传统的非线性回归函数预测模型,提高了预测精度,效果更好。更多还原

【Abstract】 North China Plain has little precipitation and more evaporation in spring which makes the winter wheat prone to have water deficit. In particular, the North China Plain itself has a serious water shortage problem, the traditional flood irrigation method is a waste of valuable water resources, and therefore this region should develop an efficient water-saving agriculture. Although large-scale irrigation machinery is better for saving water and energy, but the not unified North China Plain arable land, more dispersed water management, only small arable land for family workshops, much expensive large-scale irrigation equipment, long time no machine for irrigation in this region, all of these factors make the big machine promotion full of difficult, therefore light and small-scaled machine are more suitable for the local status. The irrigation machinery is capable of operating at improving irrigation efficiency, reducing the irrigation labor force and saving water resources. This paper presents self-propelled real-time variable irrigation machinery, fitted with reel machines to complete precision irrigation in small rectangular plots. Before irrigation, the machine use remote controlled DC motor as a power source for irrigation vehicle, pulling out the PE hose of the reel machine; During irrigation, pressured water rotate the water-driven turbine to wind up the PE hose recycling the irrigation vehicle. By using of irrigation map and control system to realize a real time variable irrigation in the winter wheat field, with PE hose pulling in and out to complete the irrigation task during machine walking. The development of self-propelled variable irrigation machines is capable of improving irrigation efficiency, saving water and energy. This paper completed the following tasks:1. Completed the design of self-propelled real-time variable irrigation machine, the machine is compact and flexible and can be used for small plots of crops in the North China Plain for irrigation operations which achieved a small plot irrigation mechanization. Test the irrigation machine performance and obtain its flow characteristics at different pressures which can be achieved uniform irrigation within the depth range of10mm-80mm, meet the requirements of the irrigation water intensity of winter wheat. The PE reel runs with an constant speed and the coefficient of Christiansen along the main pipe is98.91%. Irrigation depth can be achieved by adjusting inlet pressure and travel speed. Only one person is needed to operate the irrigation machinery which reduce the labor intensity and improve irrigation efficiency.2. Using VB language to write an GPS-based real-time variable irrigation control system program, designing a microcomputer control system circuit by Protel software, firing a single-chip control procedures, printing the controller circuit board and completing the entire control system hardware and software design. Through man-machine interface, design irrigation prescription map based on soil moisture information, control solenoid valve switch on and off to complete real-time variable irrigation according to different water demand in corresponding positions.3. Two winter wheat growing season during2011-2012and2012-2013to conduct irrigation trials of winter wheat field in China Agricultural University Experimental Station of Hebei Wuqiao, respectively, sprinkler irrigation, drip irrigation, no irrigation and mechanical irrigation methods were compared in the experimental study to verify the feasibility of self-propelled variable irrigation machine. Overall, through the rational design of irrigation schemes and use of irrigation machine is able to ensure the growth of winter wheat yield, constituted yield factors, plant height, ear length, biomass and harvest index remained at normal levels, irrigation machine is better than flood irrigation and sprinkler irrigation in his region, and can achieve similar effect with drip irrigation when irrigate similar amount of water, but the yield is increased3.25%, WUE is increased10.1%.4. The way of using infrared cameras to get CWSI are more efficient method, cooperate with BP neural network to predict yield of winter wheat will enhance the forecast accuracy, compared to traditional non-linear regression prediction model, this combination can predict higher accuracy and gain better results. Production and CWSI have strong negative correlation, which verify the same results with the previous findings.This paper develops a new type of self-propelled real-time variable irrigation machine, which can reduce labor intensity and improve irrigation work efficiency, promote the development of irrigated agriculture mechanization. By optimizing crop cultivation and irrigation patterns based on the machine is easy to realize energy and water conservation, promote agricultural agronomic technology integration, achieve win-win situation of lower energy consumption and high crop yield and efficiency.更多还原