Authors

Abstract

Aiming at the problems of poor applicability of traditional header height detection mechanism, poor stability and large lag of automatic control system of combine harvesters, an automatic control system of header height of combine harvester was designed, which mainly included the profiling mechanism, controller, proportional valve, manual operation handle and display module. The profiling detection mechanism was composed of angle sensor, profiling plate, torsion spring and other structures. The key structural parameters of the profiling mechanism were determined by using the Adams simulation software and its working performance was verified. The gray prediction PID algorithm of header height was used to reduce the lag of the control model. The control system detected the height of the header from the ground through the profiling mechanism. After being processed by the controller, the height of the header was changed by adjusting the expansion of the header oil cylinder. The field test results showed that the working performance of the header automatic control system was stable. Under the working conditions of preset header height of 100mm and 200mm, the average deviation of the control system was within 21 mm, which met the real-time control demand of header height during normal operation of combine harvester. This research could provide intelligent design methods of combine harvesters.

Abstract in Chinese

针对传统联合收获机割台高度检测机构适用性差、自动调控系统稳定性不佳与滞后性大的问题,设计了一种联合收获机割台高度自动控制系统,主要包括随地仿形机构、控制器、比例阀、手动操作手柄和显示模块等。随地仿形检测机构由角度传感器、仿形板、扭簧等结构组成,利用Adams仿真软件确定了仿形机构关键结构参数并验证了其工作性能,建立了联合收获机割台高度与传感器信号之间的关系模型,采用割台高度灰色预测PID控制算法减小控制模型滞后性,控制系统通过仿形机构检测割台离地高度,经控制器处理后,通过调整割台油缸伸缩量实现割台高度变化。田间试验结果表明,割台自动调控系统工作性能稳定,在预设割台高度100mm及200mm工况下,控制系统调节的平均偏差均在21mm内,满足联合收获机正常作业时割台高度实时调控需求。本研究可为联合收获机的智能化设计提供参考。