基于时空耦合补偿的处方图式稻麦变量施肥系统研究

Research of Prescription Map-based Variable Rate Fertilization System for Rice and Wheat with Spatio-temporal Coupling Compensation Method

摘要:

针对传统施肥方式均一化投入易造成资源浪费、环境污染以及现有变量施肥系统滞后补偿方法适应性不足的问题，本研究设计了一种基于时空耦合补偿的处方图式稻麦变量施肥系统。采用低成本STM32F407控制芯片和CAN总线控制架构对控制系统和核心中央控制器进行设计，结合ArcMap地理信息系统平台提出基于农学专家决策的数字化变量施肥处方图生成方法，开发了支持GPS报文接收、解析、处方图加载与高效检索的人机交互软件，提出了施肥量调节位置时空耦合校正模型，通过排肥口动态定位数学建模和滞后时间自学习算法，实现了系统响应时间的现场自动标定与动态补偿。台架试验表明，滞后时间自学习算法在不同作业速度（4~8km/h）和施肥量梯度（0~450kg/hm2、0~750kg/hm2、450~750kg/hm2）下的计算准确率均在90.5%以上；田间试验显示，开启时空耦合校正后，50m作业段内平均施肥量精度达97.4%，较无校正状态提升8.0个百分点，且作业速度增至8km/h时精度波动仅2.5个百分点。该系统为稻麦变量施肥提供了高精度、低成本的智能化解决方案。

Abstract:

Aiming to address the issues of resource waste and environmental pollution caused by uniform fertilization in traditional methods, as well as the inadequate adaptability of existing variable-rate fertilization systems’lag compensation approaches, a prescription map-based variable-rate fertilization system for rice and wheat featuring spatio-temporal coupling compensation function was designed. The system employed an STM32F407 chip and CAN bus architecture for the control unit and central processor. Integrated with ArcMap GIS platform, it proposed a digital prescription map generation method based on agronomic expert decisions. The developed human-machine interface software supported GPS message reception/parsing, prescription map loading, and high-efficiency retrieval. Innovatively, a spatio-temporally coupled calibration model for fertilizer application adjustment was established through dynamic outlet positioning modeling and lag time self-learning algorithm, enabling automatic field calibration and dynamic compensation of system response time. Bench tests demonstrated that the self-learning algorithm achieved over 90.5% accuracy across working speeds (4~8km/h) and fertilization gradients (0~450kg/hm2，0~750kg/hm2，450~750kg/hm2). Field trials showed that with spatio-temporal calibration enabled, the average fertilization accuracy reached 97.4% within 50-meter segments—an 8.0 percentage points improvement over non-calibrated status—while maintaining only 2.5 percentage points accuracy fluctuation at 8km/h. This system provided a high-precision, low-cost intelligent solution for variable-rate fertilization in rice/wheat cultivation, offering technical support for China’s national policy of reducing fertilizer use while increasing efficiency.