为降低谷物联合收获机收获作业时因割台高度不当造成的粮食损失,减少割茬高度过高对后续播种环节的影响,利用传感器监测地面起伏变化,设计了一种基于 PID 调控的割台高度自适应控制系统;设计了基于角度传感器的地面仿形监测机构与割台高度反馈机构,标定并拟合出割台高度与传感器电压信号的线性关系;加装集成式电磁比例阀替换原有割台控制电控换向阀,并进行 PWM 控制试验.同时,分析了整套自适应控制系统的结构与电液控制原理,并进行了多组田间对照试验,结果表明:设计的基于地面仿形的割台高度自适应控制系统具有稳定的响应速度和理想的控制效果,在平原地区作业时相较于传统人工控制割台的方式有明显的优势,能适应平原地形环境下 5~11km/h 收获作业速度的要求.研究结果为后续无人驾驶谷物联合收获机的研发设计提供了割台装置控制策略的理论依据.
In order to reduce the grain loss caused by inappropriate header height during the harvest operation of grain combine harvester,and reduce the impact of too high stubble height on subsequent sowing links.In this paper,the sen-sor is used to monitor the fluctuation of the ground,and a header height adaptive control system based on PID regulation is designed.The ground profiling monitoring mechanism and header height feedback mechanism based on angle sensor are designed,and the linear relationship between header height and sensor voltage signal is calibrated and fitted.Install an integrated electromagnetic proportional valve to replace the original header control electronic directional valve,and con-duct PWM control test.The structure and electro-hydraulic control principle of the whole adaptive control system are an-alyzed,and several groups of field control experiments are carried out.Experiments show that the designed header height adaptive control system based on ground profiling has stable response speed and good control effect.When working in plain area,it has obvious advantages compared with the traditional manual control of header,and can meet the require-ments of 5-11km/h harvesting speed in plain terrain environment.This study provides a theoretical basis for the control strategy of header device for the research and design of unmanned grain combine harvester.