Development and test of a small robotic system for in-field undisturbed soil sampling

doi:10.12398/j.issn.2096-7217.2024.01.002

Abstract

Abstract:

Agricultural robot is one of the hottest topics in the field of agricultural machineries. Domestic and foreign research on robot mobile platforms for greenhouse/farmland/orchard operations （weeding， fertilization， spraying， picking， etc.） has achieved preliminary results， but mobile robotic system for soil sampling is still seldom found in literatures. Undisturbed soil sampling is an important basis for analyzing soil mechanical properties. If the original state of the soil sample cannot be guaranteed， it will be difficult to obtain accurate research results through subsequent laboratory physical and mechanical testing and analysis. To address this issue， we developed a farmland soil collection robot mobile platform with compact structure， strong pass ability， good soil extraction quality， and high soil extraction efficiency， put forward the design scheme of the mechanical system and control system and carried out preliminary field trial research. The main contents of this research are as follows： First， the design of robotic mobile platform was conducted， by determining differential steering mode， fulfilling mechanical design， selecting hardware components， and building control software framework. The wheelbase and track width of the platform were 960 mm and 600 mm， respectively. The power of the in-wheel motor was 1 000 W. The movement of the platform could be controlled through both speed control knob and remote-control handle. Second， an on-board layer soil sampling equipment was developed， which worked in a hydraulic screw-in mode. The main structure parameters of the sampler were determined based on theoretical analysis， which were validated with a finite element analysis software-ANSYS. Third， field tests were also conducted to test the mobility and soil sampling performances of the robot system. The maximum obstacle crossing height and climbing slope of the robot were 80 mm and 35°， respectively. Based on the shear strength testing results of soil samples in depth 0 to 200 mm， we knew that the internal friction angle of the soil samples， which came from the proposed new system， had no significant differences compared to those coming from cutting ring sampling， with a P-value of 0.866 at the confidence level of 0.05. Similarly， for the soil samples in depth 0 to 100 mm and 100 to 200 mm， the variances of soil cohesion from our new system also had no significant differences compared to those from cutting ring sampling， with P-values of 0.145 and 0.717 at the confidence level of 0.05， respectively. The soil extraction efficiency comparison test results showed that the soil extraction device only took 3 to 5 minutes to complete one soil extraction.

Key words: agricultural robot, mobile platform, in-field, undisturbed soil, soil sampler

CLC Number:

YAN Quantao, LI Lixia, QIU Quan, CONG Yue. Development and test of a small robotic system for in-field undisturbed soil sampling[J]. Journal of Intelligent Agricultural Mechanization, 2024, 5(1): 12-22.

Figures/Tables 19

References 21

1	付晓莉，邵明安，吕殿青. 土壤持水特征测定中质量含水量、吸力和容重三者间定量关系Ⅱ.原状土壤［J］. 土壤学报， 2008， 45（1）： 50-55.
	FU Xiaoli， SHAO Ming'an， Dianqing LÜ. Quantitative relationship between mass water content， pressure head and bulk density in determination of soil water retention characteristics II. undisturbed soils ［J］. Acta Pedologica Sinica， 2008， 45（1）： 50-55.
2	杨建立. 农业用机动取土器的研制与失效分析［D］. 郑州：河南农业大学， 2013.
	YANG Jianli. Development and failure analysis on motorized soil for agriculture ［D］. Zhengzhou： Henan Agricultural University， 2013.
3	陈亮之，张军. 田间取土器的研究进展［J］. 机械研究与应用， 2016， 29（3）： 212-213， 216.
	CHEN Liangzhi， ZHANG Jun. Research progress of the soil sampler ［J］. Mechanical Research & Application， 2016， 29（3）： 212-213， 216.
4	HELLBUSCH J A. Under frame mounted soil sampler for light trucks ［P］. US： US5076372，1991-12-31.
5	ABU-HAMDEH N H， AL-JALIL H F. Hydraulically powered soil core sampler and its application to soil density and porosity estimation ［J］. Soil & Tillage Research， 1999， 52（12）： 113-120.
6	HUBERS E. Vehicle mounted soil sampler ［P］. US： US6363803， 2002-04-02.
7	王健，蔡焕杰，陈新明，等. 支架旋转式原状土取样器［P］. 中国： CN1609583， 2005-04-27.
8	何云峰，吴靖霆，陈杰，等. 一种齿轮式土壤采样器及其采样方法［P］. 中国： CN104330280A， 2015-02-04.
9	周雪青，李洪文，何进，等. 土壤容重测定用分段式原状取土器的设计［J］. 农业工程学报， 2008， 24（8）： 127-130.
	ZHOU Xueqing， LI Hongwen， HE Jin， et al. Design of multi-segment in situ soil sampler testing bulk density ［J］. Transactions of the Chinese Society of Agricultural Engineering， 2008， 24（8）： 127-130.
10	张凯，刘成良. 车载液压振动式土壤采集装置研究［J］. 南京信息工程大学学报（自然科学版）， 2010， 2（4）： 297-301.
	ZHANG Kai， LIU Chengliang. Study on vehicle-mounted soil sampling device by hydraulic vibration ［J］. Journal of Nanjing University of Information Science & Technology， 2010， 2（4）： 297-301.
11	BAKKER T. An autonomous robot for weed control： Design， navigation and control ［D］. Wageningen， the Netherlands： Wageningen University， 2009.
12	COUSINS D. Bosch BoniRob robot set to make field work easier for farmers ［J］. Farmers Weekly， 2015， 1052： 7.
13	GRIMSTAD L， CONG D P， PHAN H T， et al. On the design of a low-cost， light-weight， and highly versatile agricultural robot ［C］// IEEE International Workshop on Advanced Robotics and its Social Impacts， Shanghai， China， July 8-10， 2016： 1-6.
14	ZHANG Z Z， KAYACAN E， THOMPSON B， et al. High precision control and deep learning-based corn stand counting algorithms for agricultural robot ［J］. Autonomous Robots， 2020， 44（7）： 1289-1302.
15	杨世胜，张宾，于曙风，等. 电磁诱导农用喷雾机器人路径导航系统的设计与实现［J］. 机器人，2007， 29（1）： 78-81， 87.
	YANG Shisheng， ZHANG Bin， YU Shufeng， et al. Design and implementation of the navigation system for an electromagnetic guided agricultural spraying robot ［J］. Robot， 2007， 29（1）： 78-81， 87.
16	罗锡文，区颖刚，赵祚喜，等. 农用智能移动作业平台模型的研制［J］. 农业工程学报， 2005， 21（2）： 83-85.
	LUO Xiwen， Yinggang OU， ZHAO Zuoxi， et al. Research and development of intelligent flexible chassis for precision farming ［J］. Transactions of the Chinese Society of Agricultural Engineering， 2005， 21（2）： 83-85.
17	QIU Q， FAN Z Q， MENG Z J， et al. Extended ackerman steering principle for the coordinated movement control of a four wheel drive agricultural mobile robot ［J］. Computers and Electronics in Agriculture， 2018， 152： 40-50.
18	FAN Z Q， SUN N， QIU Q， et al. In situ measuring stem diameters of maize crops with a high-throughput phenoltyping robot ［J］. Remote Sensing， 2022， 14（4）： 1030.
19	张力群. 取土器的合理选用与改进［J］. 探矿工程（岩土钻掘工程）， 2003（3）： 33-34.
	ZHANG Liqun. Reasonable selection and improvement of soil samplers ［J］. Exploration Engineering（Rock & Soil Drilling and Tunneling）， 2003（3）： 33-34.
20	张剑锋，俞灿明. 关于中国系列薄壁取土器的建议［J］. 上海地质， 1983（4）： 19-27， 47.
21	刘海刚. 薄壁取土器的技术参数及性能测试［J］. 勘察科学技术， 1989（4）： 32-38.

入土方式	优点	缺点
直压式	操作简单，不易造成土体压实变形，利于原状土柱的获取及保持	不利于克服土体阻力
重力锤击式	可有效克服土体阻力，能够使用在土质较硬的场合	取土过程中取土器震动较大、运动无规律，易造成土体结构破坏，不利于原状土的获取
直压旋入式	原状土样的质量较高，管靴刃口的旋转切割作用能够有效降低入土阻力	操作方式相对复杂

入土方式	优点	缺点
直压式	操作简单，不易造成土体压实变形，利于原状土柱的获取及保持	不利于克服土体阻力
重力锤击式	可有效克服土体阻力，能够使用在土质较硬的场合	取土过程中取土器震动较大、运动无规律，易造成土体结构破坏，不利于原状土的获取
直压旋入式	原状土样的质量较高，管靴刃口的旋转切割作用能够有效降低入土阻力	操作方式相对复杂

技术参数名称	技术参数数值
外观尺寸/（mm×mm×mm）	340×160×1 100
液压电机功率/kW	1.2
减速机构减速比	1:3
升降油缸行程/mm	250
取土深度/mm	0~200
所取土样直径/mm	61.8
整机质量/kg	50

技术参数名称	技术参数数值
外观尺寸/（mm×mm×mm）	340×160×1 100
液压电机功率/kW	1.2
减速机构减速比	1:3
升降油缸行程/mm	250
取土深度/mm	0~200
所取土样直径/mm	61.8
整机质量/kg	50

取样层数（对应取样深度）	平均抗剪强度/kPa
	100 kPa加载		200 kPa加载		300 kPa加载		400 kPa加载
	环刀法	新系统	环刀法	新系统	环刀法	新系统	环刀法	新系统
一（0~2 cm）	73.6	75.2	121.2	125.9	185.4	171.4	224.6	227.5
二（2~4 cm）	69.0	72.1	111.9	119.4	163.6	167.8	205.7	209.8
三（4~6 cm）	66.0	78.2	101.2	119.7	155.3	187.0	197.8	230.6
四（6~8 cm）	75.9	76.0	129.0	116.3	190.1	182.3	232.1	227.5
五（8~10 cm）	79.8	81.3	130.5	130.5	191.6	190.1	245.7	231.2
六（10~12 cm）	76.7	78.2	123.7	125.7	194.8	186.4	215.0	206.6
七（12~14 cm）	75.3	92.6	136.8	121.2	189.2	187.0	208.7	224.4
八（14~16 cm）	101.2	87.0	135.2	135.4	163.6	183.8	247.7	233.7
九（16~18 cm）	98.3	91.5	132.1	139.9	187.1	183.5	239.8	239.9
十（18~20 cm）	89.0	92.0	139.0	132.1	177.6	179.2	225.9	231.7