基于加速度补偿的土壤紧实度测量方法与传感器设计  

Soil Compactness Measuring Method Based on Acceleration Compensation and Sensor Design

作　　者：于文华[1] 田昊[1,2] 梁超[1,2] 李成豪[1,2] 赵燕东[1,2] 

机构地区：[1]北京林业大学工学院,北京100083 [2]北京林业大学城乡生态环境北京实验室,北京100083

出　　处：《农业机械学报》2017年第4期250-256,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(31371537);北京市科技计划项目(Z116100000916012);北京市共建项目专项

摘　　要：针对目前基于圆锥指数的土壤紧实度测量中,无法消除土壤摩擦力对紧实度测量的影响,要求检测传感器匀速贯入土壤,因此存在使用不便、精度不高的难题。为了提高土壤紧实度实时测量方法的精度及可操作性,在圆锥指数方法基础上,设计了土壤紧实度实时检测传感器,并加入了加速度的同步测量,消除了使用过程中金属杆插入速度不均造成的误差,提高了土壤紧实度测量精度。通过大量试验验证了自制传感器具有较好的静态性能和动态性能,其测量范围为0~900 k Pa,灵敏度为0.041 896,稳定性测量标准差为5 k Pa,测量精度为±0.02%FS,超调量为7.81%,过渡时间为0.632 s。与美国SC-900型土壤紧实度仪对比其准确性的线性拟合决定系数均达到0.96以上,结果表明设计的土壤紧实度传感器与SC-900型土壤紧实度仪在实际测量中性能相当,且使用更方便、价格更低廉。为农林生产、环境保护及生态监测提供了一种具有自主知识产权、精准获取土壤紧实度的有效手段。In view of the present measurement of soil compactness based on the cone index, eliminating the influence of soil friction on compactness measuring is impossible.It needs to ensure sensor is inserted into the soil at constant speed, thus it is difficult to use and the accuracy is not high. In order to improve the real-time measurement precision and maneuverability of soil compactness, a real-time soil compactness detection sensor was designed based on the cone index, and the synchronous measurement of acceleration was realized, which eliminated the error caused by different speed in the process of the metal rod inserting into soil, as well as improved soil compactness measuring precision. Homemade sensor had good static characteristics and dynamic characteristics through a large number of test. Measuring range was 0-7800kPa, sensibility was 0.041896, the stability of the standard deviation was 5kPa, measuring accuracy was ±0.02%FS, overshoot was 7.81%, and transient time was 0.632s. Compared with SC-900 soil compactness meter of the United States, its accuracy of the linear fitting coefficient of decision reached more than 0.96. The results showed that the homemade soil compactness sensor and SC-900 soil compactness meter had consistency of performance in the actual measurement, and homemade soil compactness sensor was more convenient and cheaper.

关 键 词：土壤紧实度 传感器 加速度 圆锥指数 静态特性 动态特性 

分 类 号：S152.9[农业科学—土壤学] TU432[农业科学—农业基础科学]