基于线结构激光传感器的土壤表面粗糙度测量方法研究
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摘要
土壤表面粗糙度是农作物种植、灌溉和收获等田间管理必须考虑的作业参数,也是精准农业发展中亟待解决的关键问题之一。针对土壤表面粗糙度缺乏快速检测手段的问题,提出一种基于线结构激光传感器的土壤表面粗糙度测量方法。利用半导体红光激光器、CCD工业相机、计算机及支架等构建测量系统,采集土壤样本的表面图像数据,借助MATLAB获取其三维点云模型,实现土壤表面的三维曲面建模并计算曲面面积。定义土壤表面三维曲面面积与其平面面积的比值为表征土壤表面粗糙度的量,并通过对比4个颗粒度土壤样本的该值范围,确定了判别样本表面粗糙度的阈值。利用3种土槽旋耕土壤表面样本对系统和算法进行验证,比值处于1.214～1.939之间,检测结果均与样本实际特征相符合。该方法能够检测和判断土壤表面的颗粒粗糙程度。
As one of the main parameters for evaluating mechanized land leveling technology,which is the basic link of modernization and precision agriculture,soil surface roughness is also a factor that must be considered for field management such as crop planting,irrigation,harvesting and so on.However,a rapid and low-cost accuracy measurement method is absent currently.In this work,we proposed a method for rapidly evaluating soil surface roughness.The soil surface roughness was assessed according to the images generated by a self-design system based on line structure laser light principle.The parameters of the system was determined by a preliminary experiment.The accuracy of the system was 0.126 mm.Considering the requirements by common crops such as oilseed rape,potato,rice and vegetables,we screened the soils with 4 aperture sieves.The obtained soil particle size was higher than 2 mm,higher than 0.9 mm and not less than 2 mm,higher than 0.3 mm and not less than 0.9 mm,and not higher than 0.3 mm.By the self-design system,soil samples images were obtained.After segmentation,morphological processing and edge detection,the images of prepared soil samples were processed for extracting the center sub-pixels of structured light stripe and the sub-pixels were combined together for obtain the 3 D point cloud of each sample.With delaunay triangulation algorithm,the 3 D surface modeling of the soil surface was established and the curve surface area was calculated.The ratio of curved surface area to surface area was calculated in order to characterize the flatness of the soil surface.The threshold values of the ratio for determining the sample surface roughness were determined by analyzing the ratio values of 4 samples with different particle sizes.The larger ratio values indicate more rough soil surface.Based on the ratio,soil was considered as relatively flat,relatively dense,relatively rough and rough when the difference of ratio and 1 was 0,higher than 0 and not higher than 0.5,higher than 0.5 and not higher than 1,and higher than 1.The method was validated by soil bin test.The soil samples in soil bin with treatments in uncultivated,shallow rotary tillage and deep rotary tillage conditions were used for the validation of the system and algorithm.Meanwhile,our method was compared with probe method.The results showed that the ratio values of surface samples with uncultivated,shallow rotary tillage and deep rotary tillage increased gradually.The ratio was 1.214,1.633 and 1.939 for the samples in uncultivated,shallow rotary tillage and deep rotary tillage conditions,respectively.The change of the ratio was consistent with that of the standard deviation of relative height difference of sample surface by the probe method.Based on the ratio,the sample surface in the treatments of uncultivated,shallow rotary tillage and deep rotary tillage was considered as relatively dense,relatively rough and relatively rough,respectively.The results were consistent with the actual characteristics of the samples.These results indicated that the presented measurement method could be applied in soil surface roughness assessment.
As one of the main parameters for evaluating mechanized land leveling technology,which is the basic link of modernization and precision agriculture,soil surface roughness is also a factor that must be considered for field management such as crop planting,irrigation,harvesting and so on.However,a rapid and low-cost accuracy measurement method is absent currently.In this work,we proposed a method for rapidly evaluating soil surface roughness.The soil surface roughness was assessed according to the images generated by a self-design system based on line structure laser light principle.The parameters of the system was determined by a preliminary experiment.The accuracy of the system was 0.126 mm.Considering the requirements by common crops such as oilseed rape,potato,rice and vegetables,we screened the soils with 4 aperture sieves.The obtained soil particle size was higher than 2 mm,higher than 0.9 mm and not less than 2 mm,higher than 0.3 mm and not less than 0.9 mm,and not higher than 0.3 mm.By the self-design system,soil samples images were obtained.After segmentation,morphological processing and edge detection,the images of prepared soil samples were processed for extracting the center sub-pixels of structured light stripe and the sub-pixels were combined together for obtain the 3 D point cloud of each sample.With delaunay triangulation algorithm,the 3 D surface modeling of the soil surface was established and the curve surface area was calculated.The ratio of curved surface area to surface area was calculated in order to characterize the flatness of the soil surface.The threshold values of the ratio for determining the sample surface roughness were determined by analyzing the ratio values of 4 samples with different particle sizes.The larger ratio values indicate more rough soil surface.Based on the ratio,soil was considered as relatively flat,relatively dense,relatively rough and rough when the difference of ratio and 1 was 0,higher than 0 and not higher than 0.5,higher than 0.5 and not higher than 1,and higher than 1.The method was validated by soil bin test.The soil samples in soil bin with treatments in uncultivated,shallow rotary tillage and deep rotary tillage conditions were used for the validation of the system and algorithm.Meanwhile,our method was compared with probe method.The results showed that the ratio values of surface samples with uncultivated,shallow rotary tillage and deep rotary tillage increased gradually.The ratio was 1.214,1.633 and 1.939 for the samples in uncultivated,shallow rotary tillage and deep rotary tillage conditions,respectively.The change of the ratio was consistent with that of the standard deviation of relative height difference of sample surface by the probe method.Based on the ratio,the sample surface in the treatments of uncultivated,shallow rotary tillage and deep rotary tillage was considered as relatively dense,relatively rough and relatively rough,respectively.The results were consistent with the actual characteristics of the samples.These results indicated that the presented measurement method could be applied in soil surface roughness assessment.
引文
[1]Burwell R E,Larson W E.Infiltration as influenced by tillage-induced random roughness and pore space[J].Soil Science Society of America Journal,1969,33(3):449.
[2]Sun Y,Lin J,Lammers P S,et al.Estimating surface porosity by roughness measurement in a silt-loam field[J].Journal of Plant Nutrition and Soil Science,2006,169(5):630-632.
[3]R?mkens M,Helming K,Prasad S N.Soil erosion under different rainfall intensities,surface roughness,and soil water regimes[J].Catena,2002,46(2):103-123.
[4]聂卫波,马孝义.畦田Philip入渗参数和田面综合糙率同步推求[J].农业机械学报,2009,40(5):39-44.Nie Weibo,Ma Xiaoyi.Synchronously determining philip infiltration parameter and synthesis roughness model of border irrigation[J].Transactions of the Chinese Society for Agricultural Machinery,2009,40(5):39-44.(in Chinese with English abstract)
[5]Zobeck T M,Onstad C A.Tillage and rainfall effects on random roughness:A review[J].Soil&Tillage Research,1987,9(1):1-20.
[6]Keyser E D,Vernieuwe H,Lievens H,et al.Assessment of SAR-retrieved soil moisture uncertainty induced by uncertainty on modeled soil surface roughness[J].International Journal of Applied Earth Observation&Geoinformation,2012,18(1):176-182.
[7]Davenport I J,Sandells M J,Gurney R J.The effects of scene heterogeneity on soil moisture retrieval from passive microwave data[J].Advances in Water Resources,2008,31(11):1494-1502.
[8]Saleh A.Soil roughness measurement:Chain method[J].Journal of Soil&Water Conservation,1993,48(6):527-529.
[9]Merrill S D.Comments on the chain method for measuring soil surface roughness:Use of the chain set[J].Soil Science Society of America Journal,1998,62(4):1147-1149.
[10]Moreno R G,álvarez M C D,Alonso A T,et al.Tillage and soil type effects on soil surface roughness at semiarid climatic conditions[J].Soil&Tillage Research,2008,98(1):35-44.
[11]Huang Chi hua,Bradford J M.Depressional storage for Markov-Gaussian surfaces[J].Water Resources Research,1990,26(9):2235-2242.
[12]Kruipers H.A reliefmeter for soil cultivation studies[J].Netherlands Journal of Agricultural Science,1957(15):255-262.
[13]Podmore T H,Huggins L F.An automated profile meter for surface roughness measurements[J].Transactions of the American Society of Agricultural Engineering,1981,24(3):663-665,669.
[14]Taconet O,Ciarletti V.Estimating soil roughness indices on a ridge-and-furrow surface using stereo photogrammetry[J].Soil&Tillage Research,2007,93(1):64-76.
[15]Wegmann H,Rieke-Zapp,D Folke S.Digital photogrammetry for measuring soil surface roughness[C]//Proc.ASPRS 2001Annual Conference,St Louis,USA,2001.
[16]Warner W S.Mapping a three-dimensional soil surface with hand-held 35 mm photography[J].Soil&Tillage Research,1995,34(3):187-197.
[17]Robichaud P R,Molnau M.Measuring soil roughness changes with an ultrasonic profiler[J].Transactions of the ASAE,1990,33(6):1851-1858.
[18]李宗南,陈仲新,王利民,等.基于红外结构光三维技术的土壤表面粗糙度测量[J].农业工程学报,2013,29(21):137-142.Li Zongnan,Chen Zhongxin,Wang Limin,et al.Ameasuring method of soil surface roughness using infrared structured light 3D technology[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2013,29(21):137-142.(in Chinese with English abstract)
[19]蔡祥,孙宇瑞,林剑辉,等.基于激光反射的土壤表面粗糙度测量装置设计与试验[J].农业机械学报,2010,41(1):68-71.Cai Xiang,Sun Yurui,Lin Jianhui,et al.Design of a laser scanner for characterizing soil surface roughness[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2010,41(1):68-71.(in Chinese with English abstract)
[20]Croft H,Anderson A K,Kuhn N J.Characterizing soil surface roughness using a combined structural and spectral approach[J].European Journal of Soil Science,2010,60(3):431-442.
[21]Aguilar M A,Aguilar F J,Negreiros J.Off-the-shelf laser scanning and close-range digital photogrammetry for measuring agricultural soils microrelief[J].Biosystems Engineering,2009,103(4):504-517.
[22]张胜宾,黄培奎,赵祚喜.土壤表面粗糙度检测方法研究[J].农机化研究,2016(11):257-262.Zhang Shengbin,Huang Peikui,Zhao Zuoxi.A research on soil surface roughness measurement-methods[J].Journal of Agricultural Mechanization Research,2016(11):257-262.(in Chinese with English abstract)
[23]温鹏飞,郭华.土地粗糙度测算方法研究[J].建材发展导向,2017,15(19):378-380.Wen Pengfei,Guo Hua.Research on the method of calculating land levelness[J].Development Guide to Building Materials,2017,15(19):378-380.(in Chinese with English abstract)
[24]Fofi D,Sliwa T,Voisin Y.A comparative survey on invisible structured light[J].Proceedings of SPIE-The International Society for Optical Engineering,2004,5303:90-97.
[25]Salvi J,Jordi Pagès,Batlle J.Pattern codification strategies in structured light systems[J].Pattern Recognition,2004,37(4):827-849.
[26]Shirai Y.Recognition of polyhedrons with a rage finder[J].Pattern Recognition,1972,4(3):243-250.
[27]Valkenburg R J,Mcivor A.Accurate 3d measurement using a structured light system[J].Proceedings of SPIE-The International Society for Optical Engineering,1998,16(2):99-110.
[28]Depiero F W,Trivedi M M.3-D computer vision using structured light:Design,calibration,and implementation issues[J].Advances in Computers,1996,43(8):243-278.
[29]张国忠,周勇,卢元爽,等.双螺旋旋耕埋草模型刀辊工作扭矩试验[J].华中农业大学学报,2017,36(3):101-106.Zhang Guozhong,Zhou Yong,Lu Yuanshuang,et al.Torque experiment of model rotary knife roller of double spiral rotary tillage and stubble-mulch machine[J].Journal of Huazhong Agricultural University,2017,36(3):101-106.(in Chinese with English abstract)
[30]Lawson C.Software for C1 surface interpolation[M]//Rice JM.Mathematical Software III.New York:Academic Press,1977:161-194.
[2]Sun Y,Lin J,Lammers P S,et al.Estimating surface porosity by roughness measurement in a silt-loam field[J].Journal of Plant Nutrition and Soil Science,2006,169(5):630-632.
[3]R?mkens M,Helming K,Prasad S N.Soil erosion under different rainfall intensities,surface roughness,and soil water regimes[J].Catena,2002,46(2):103-123.
[4]聂卫波,马孝义.畦田Philip入渗参数和田面综合糙率同步推求[J].农业机械学报,2009,40(5):39-44.Nie Weibo,Ma Xiaoyi.Synchronously determining philip infiltration parameter and synthesis roughness model of border irrigation[J].Transactions of the Chinese Society for Agricultural Machinery,2009,40(5):39-44.(in Chinese with English abstract)
[5]Zobeck T M,Onstad C A.Tillage and rainfall effects on random roughness:A review[J].Soil&Tillage Research,1987,9(1):1-20.
[6]Keyser E D,Vernieuwe H,Lievens H,et al.Assessment of SAR-retrieved soil moisture uncertainty induced by uncertainty on modeled soil surface roughness[J].International Journal of Applied Earth Observation&Geoinformation,2012,18(1):176-182.
[7]Davenport I J,Sandells M J,Gurney R J.The effects of scene heterogeneity on soil moisture retrieval from passive microwave data[J].Advances in Water Resources,2008,31(11):1494-1502.
[8]Saleh A.Soil roughness measurement:Chain method[J].Journal of Soil&Water Conservation,1993,48(6):527-529.
[9]Merrill S D.Comments on the chain method for measuring soil surface roughness:Use of the chain set[J].Soil Science Society of America Journal,1998,62(4):1147-1149.
[10]Moreno R G,álvarez M C D,Alonso A T,et al.Tillage and soil type effects on soil surface roughness at semiarid climatic conditions[J].Soil&Tillage Research,2008,98(1):35-44.
[11]Huang Chi hua,Bradford J M.Depressional storage for Markov-Gaussian surfaces[J].Water Resources Research,1990,26(9):2235-2242.
[12]Kruipers H.A reliefmeter for soil cultivation studies[J].Netherlands Journal of Agricultural Science,1957(15):255-262.
[13]Podmore T H,Huggins L F.An automated profile meter for surface roughness measurements[J].Transactions of the American Society of Agricultural Engineering,1981,24(3):663-665,669.
[14]Taconet O,Ciarletti V.Estimating soil roughness indices on a ridge-and-furrow surface using stereo photogrammetry[J].Soil&Tillage Research,2007,93(1):64-76.
[15]Wegmann H,Rieke-Zapp,D Folke S.Digital photogrammetry for measuring soil surface roughness[C]//Proc.ASPRS 2001Annual Conference,St Louis,USA,2001.
[16]Warner W S.Mapping a three-dimensional soil surface with hand-held 35 mm photography[J].Soil&Tillage Research,1995,34(3):187-197.
[17]Robichaud P R,Molnau M.Measuring soil roughness changes with an ultrasonic profiler[J].Transactions of the ASAE,1990,33(6):1851-1858.
[18]李宗南,陈仲新,王利民,等.基于红外结构光三维技术的土壤表面粗糙度测量[J].农业工程学报,2013,29(21):137-142.Li Zongnan,Chen Zhongxin,Wang Limin,et al.Ameasuring method of soil surface roughness using infrared structured light 3D technology[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2013,29(21):137-142.(in Chinese with English abstract)
[19]蔡祥,孙宇瑞,林剑辉,等.基于激光反射的土壤表面粗糙度测量装置设计与试验[J].农业机械学报,2010,41(1):68-71.Cai Xiang,Sun Yurui,Lin Jianhui,et al.Design of a laser scanner for characterizing soil surface roughness[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2010,41(1):68-71.(in Chinese with English abstract)
[20]Croft H,Anderson A K,Kuhn N J.Characterizing soil surface roughness using a combined structural and spectral approach[J].European Journal of Soil Science,2010,60(3):431-442.
[21]Aguilar M A,Aguilar F J,Negreiros J.Off-the-shelf laser scanning and close-range digital photogrammetry for measuring agricultural soils microrelief[J].Biosystems Engineering,2009,103(4):504-517.
[22]张胜宾,黄培奎,赵祚喜.土壤表面粗糙度检测方法研究[J].农机化研究,2016(11):257-262.Zhang Shengbin,Huang Peikui,Zhao Zuoxi.A research on soil surface roughness measurement-methods[J].Journal of Agricultural Mechanization Research,2016(11):257-262.(in Chinese with English abstract)
[23]温鹏飞,郭华.土地粗糙度测算方法研究[J].建材发展导向,2017,15(19):378-380.Wen Pengfei,Guo Hua.Research on the method of calculating land levelness[J].Development Guide to Building Materials,2017,15(19):378-380.(in Chinese with English abstract)
[24]Fofi D,Sliwa T,Voisin Y.A comparative survey on invisible structured light[J].Proceedings of SPIE-The International Society for Optical Engineering,2004,5303:90-97.
[25]Salvi J,Jordi Pagès,Batlle J.Pattern codification strategies in structured light systems[J].Pattern Recognition,2004,37(4):827-849.
[26]Shirai Y.Recognition of polyhedrons with a rage finder[J].Pattern Recognition,1972,4(3):243-250.
[27]Valkenburg R J,Mcivor A.Accurate 3d measurement using a structured light system[J].Proceedings of SPIE-The International Society for Optical Engineering,1998,16(2):99-110.
[28]Depiero F W,Trivedi M M.3-D computer vision using structured light:Design,calibration,and implementation issues[J].Advances in Computers,1996,43(8):243-278.
[29]张国忠,周勇,卢元爽,等.双螺旋旋耕埋草模型刀辊工作扭矩试验[J].华中农业大学学报,2017,36(3):101-106.Zhang Guozhong,Zhou Yong,Lu Yuanshuang,et al.Torque experiment of model rotary knife roller of double spiral rotary tillage and stubble-mulch machine[J].Journal of Huazhong Agricultural University,2017,36(3):101-106.(in Chinese with English abstract)
[30]Lawson C.Software for C1 surface interpolation[M]//Rice JM.Mathematical Software III.New York:Academic Press,1977:161-194.