基于电容传感漏播检测及记忆追赶式补偿的马铃薯精密排种系统设计与试验

Design and experiment of potato precision seeding system based on capacitive sensor detection and memory catching-up compensation

长期以来,由于勺链式马铃薯播种机光电式漏播检测系统抗干扰性差、自动补偿系统结构复杂,严重影响了马铃薯精密播种技术的推广应用。基于电容极板间因介质不同导致测量结果不同的物理机理,提出基于空间电容传感器的漏播检测方法,选用AD7745高精度电容芯片高速采集电容值,利用以穿越电容极板过程中载种与空勺测量电容最大值之差(即电容净变化量)判断是否漏播。样机土槽试验表明,漏播检测系统识别准确率高达95%以上,具有良好的抗尘、抗振性;当播种速度为0.2 m/s、0.3 m/s、0.4 m/s时,补偿系统补种成功率分别是94.32%、83.65%、73.67%,具有较强的可靠性。为非光电马铃薯排种高可靠性监测及低复杂度漏播补偿的实现提供了参考案例。

For a long time,the photoelectric miss-seeding detection system of spoon-chain potato planter has poor anti-interference and automatic compensation system has complex structure,which has seriously affected the application of potato precision seeding technology.Based on the physical mechanism that the measured capacitance is different due to the different dielectric between the capacitor plates,this study proposes a method for detecting miss-seeding based on the space capacitance sensor.In this method,the AD7745 high-precision capacitance chip is used to collect the capacitance value at high speed,and the difference between the maximum value of the capacitance measured by the carrier and the empty spoon(i.e.the net change of the capacitance)in the process of passing through the capacitance plate is used to determine the miss-seeding.The prototype machine soil trough test shows that the identification accuracy of the miss-seeding detection system is up to 95%,and it has good dust and vibration resistance.When the seeding speed is 0.2 m/s,0.3 m/s and 0.4 m/s,the success rate of the compensation system is 94.32%,83.65%and 73.67%respectively,which has strong reliability.The system is naturally dust-resistant,vibration-resistant and highly reliable.It provides a reference case for the realization of high reliability monitoring and low complexity miss-seeding compensation of non-photoelectric potato seeding.