基于MEMS传感器的仿真电子玉米果穗设计与试验

Design and Experiment of Simulated Electronic Corn Ear Based on MEMS Sensors

摘要:

针对高含水率玉米籽粒收获时存在破碎率高的问题，本文设计了一种可脱粒式仿真电子玉米果穗，电子果穗内部嵌入了IMU模块和柔性薄膜压力传感器，可以对脱粒过程中电子果穗受到的动态冲击力和静态挤压力进行实时检测，为探究脱粒过程中籽粒破碎原理提供新的技术方法。为验证该电子果穗工作性能，分别开展了动态冲击力检测试验和挤压力检测试验。动态冲击力检测试验结果表明，该电子果穗动态冲击力检测平均误差为0.91N，最大误差为2.25N，平均检测精度为98.15%。静态挤压力检测试验结果表明，电子果穗挤压力平均检测误差为2.47N，最大检测误差为7.25N，与万能试验机曲线拟合度较高，R2为0.9874。利用纵轴流脱粒装置开展了电子果穗实际工况下的脱粒试验，结果表明，电子果穗能够有效检测出其在脱粒装置中的受力情况。当喂入量为2.5kg/s、脱粒滚筒转速为450r/min、脱粒间隙为40mm、导流角度为45°时，电子果穗受到的平均冲击力为17.40N，最大冲击力为70.73N；平均挤压力为34.49N，最大挤压力为96.30N。研究结果为解析高速绕流群体果穗脱粒工况下玉米果穗受力参数提供新的技术手段，为探明籽粒发生破碎的原理提供新的研究方法。

Abstract:

Aiming to address the issue of high breakage rates during the harvesting of high-moisture corn kernels, a threshable simulated electronic corn ear was designed. It was embedded with an inertial measurement unit (IMU) module and a flexible film pressure sensor, which can detect the dynamic impact force and static squeezing force during the threshing process in real time. Furthermore, it provided a technical method for exploring the principle of grain breakage during the threshing process. To verify the working performance of the simulated electronic corn ear, dynamic impact force test and static squeezing force test were conducted separately. The results of the dynamic impact force detection test showed that the average error of the impact force was 0.91N, the maximum error was 2.25N, and the average detection accuracy was 98.15%. The results of the static squeezing pressure detection test showed that the average detection error of the squeezing pressure was 2.47N, and the maximum average detection error was 7.25N. The curve fitting degree with the universal testing machine was high, and the R2 was 0.9874. Finally, threshing tests on the simulated electronic corn ear under actual working conditions were conducted by using a longitudinal flow threshing device. The experimental results indicated that the electronic corn ear could effectively detect its stress parameters in the threshing device. Under the conditions of a feeding rate of 2.5kg/s, a threshing drum speed of 450r/min, a threshing gap of 40mm, and a guide angle of 45°, the average impact force on the electronic corn ear was 17.40N, and the maximum impact force was 70.73N. The average squeezing force was 34.49N, and the maximum squeezing force was 96.30N. The research result can provide a technical means for analyzing the stress parameters of corn ears under high-speed flow group threshing conditions, and provide a new research method for exploring the principle of grain breakage.