收获机虚拟环境模型与仿真平台构建
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摘要
为实现收获机械的设计创新以及整机作业行为和性能的仿真试验,以玉米收获机为例,采用Unity3D虚拟平台构建了收获机械三维仿真模型。根据物料流变特性,以虚拟弹簧和虚拟墙构建了植株模型,通过建立行为控制模型实现了收获机械与植株的交互,最终开发了收获仿真平台,应用该平台进行了验证试验和不同条件下的收获仿真试验。试验结果表明,构建的植株模型和虚拟收获环境符合收获机械仿真需求,仿真平台可进行收获机械作业性能的评估。
In order to realize the design innovation of harvesting equipment and the simulation test of the machine operation behavior and performance,the corn harvesting equipment was taken as an example,the 3D simulation model of harvesting equipment was built by Unity3D virtual platform. In order to simulate the deformation of the plant,according to the rheological properties,the plant model was constructed by connecting multiple cylinders with virtual springs and virtual walls. Then,establishment of behavioral models achieved interaction between harvesting equipment and plants. Finally,the harvesting simulation platform was used to verify the harvesting simulation test under different conditions,including the state change test of the plant under wind and rain,the harvesting behavior observation test of the harvesting process and the harvesting performance test of harvesting equipment with the traveling speed and planting density as factors. The result was that the fruit loss rate was decreased rapidly with the increase of speed,but the rate was decreased slowly when the speed exceeded 0. 385 m/s. At the same time,the higher the planting density was,the slower the fruit loss rate was decreased. Further analysis of variance showed that both the traveling speed and the planting density had significant effects on the harvesting performance of the harvesting equipment( P < 0. 01),which showed that the simulation platform can effectively simulate the harvesting situation and evaluate the performance of the harvesting equipment.
In order to realize the design innovation of harvesting equipment and the simulation test of the machine operation behavior and performance,the corn harvesting equipment was taken as an example,the 3D simulation model of harvesting equipment was built by Unity3D virtual platform. In order to simulate the deformation of the plant,according to the rheological properties,the plant model was constructed by connecting multiple cylinders with virtual springs and virtual walls. Then,establishment of behavioral models achieved interaction between harvesting equipment and plants. Finally,the harvesting simulation platform was used to verify the harvesting simulation test under different conditions,including the state change test of the plant under wind and rain,the harvesting behavior observation test of the harvesting process and the harvesting performance test of harvesting equipment with the traveling speed and planting density as factors. The result was that the fruit loss rate was decreased rapidly with the increase of speed,but the rate was decreased slowly when the speed exceeded 0. 385 m/s. At the same time,the higher the planting density was,the slower the fruit loss rate was decreased. Further analysis of variance showed that both the traveling speed and the planting density had significant effects on the harvesting performance of the harvesting equipment( P < 0. 01),which showed that the simulation platform can effectively simulate the harvesting situation and evaluate the performance of the harvesting equipment.
引文
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[2]臧宇,朱忠祥,宋正河,等.农业装备虚拟试验系统平台的建立[J].农业机械学报,2010,41(9):70-74,127.ZANG Yu,ZHU Zhongxiang,SONG Zhenghe,et al. Virtual experiment system platform for agricultural equipment[J].Transactions of the Chinese Society for Agricultural Machinery,2010,41(9):70-74,127.(in Chinese)
[3]邹湘军,孙健,何汉武,等.虚拟现实技术的演变发展与展望[J].系统仿真学报,2004,16(9):1905-1909.ZOU Xiangjun,SUN Jian,HE Hanwu,et al. The development and prospects of virtual reality[J]. Journal of System Simulation,2004,16(9):1905-1909.(in Chinese)
[4] ANNA P G S,FERNANDES P T,MONA L M D O,et al. An introductory guide for hybrid simulation modelers on the primary simulation methods in industrial engineering identified through a systematic review of the literature[J]. Computers&Industrial Engineering,2018,124:474-492.
[5] XIONG Juntao,LIN Rui,LIU Zhen,et al. The recognition of litchi clusters and calculation of picking point in nocturnal natural environment[J]. Biosystems Engineering,2018,166:44-57.
[6] ZHENG Y,CHENG B,HUANG Q,et al. Research on virtual driving system of a forestry logging harvester[J]. Wireless Personal Communications,2018,102(2):667-682.
[7] LIU F,LU Y,ZHANG S. A pragmatic system to support virtual assembly for military armored vehicle integrated transmission system in the virtual environment[J]. Wireless Personal Communications,2018,102(2):1337-1354.
[8] HSU C L,CHOU Y C,LI Y T,et al. Pre-operative virtual simulation and three-dimensional printing techniques for the surgical management of acetabular fractures[J/OL]. International Orthopaedics(SICOT),2018:1-8. DOI:10. 1007/s00264-018-4111-8.
[9] LOWELL V L,ALSHAMMARI A. Experiential learning experiences in an online 3D virtual environment for mental health interviewing and diagnosis role-playing:a comparison of perceived learning across learning activities[J]. Educational Technology Research and Development,2019,67(4):825-854.
[10] JENSEN L,KONRADSEN F. A review of the use of virtual reality head-mounted displays in education and training[J].Education and Information Technologies,2018,23(4):1515-1529.
[11]邹湘军,李静,孙权,等.采摘机械手虚拟设计与仿真系统的研究[J].系统仿真学报,2010,22(11):2748-2752.ZOU Xiangjun,LI Jing,SUN Quan,et al. Research on picking manipulator virtual design and simulation system[J]. Journal of System Simulation,2010,22(11):2748-2752.(in Chinese)
[12]罗陆锋,邹湘军,程堂灿,等.采摘机器人视觉定位及行为控制的硬件在环虚拟试验系统设计[J].农业工程学报,2017,33(4):39-46.LUO Lufeng,ZOU Xiangjun,CHENG Tangcan,et al. Design of virtual test system based on hardware-in-loop for picking robot vision localization and behavior control[J]. Transactions of the CSAE,2017,33(4):39-46.(in Chinese)
[13] MEUSEL C,KIEU D,GILBERT S,et al. Evaluating operator harvest technology within a high-fidelity combine simulator[J].Computers and Electronics in Agriculture,2018,148:309-321.
[14]董莹莹,赵星,王纪华.基于GPU的虚拟植物生长的双尺度自动机模型实现方法[J].农业工程学报,2011,27(5):207-212.DONG Yingying,ZHAO Xing,WANG Jihua. Rendering plants with dual-scale automaton model based on GPU[J].Transactions of the CSAE,2011,27(5):207-212.(in Chinese)
[15]李春晓,孙瑞志,戴佚舟,等.基于Unity3D的中国古代农耕虚拟场景智能展示平台[J].农业工程学报,2017,33(增刊1):308-314.LI Chunxiao,SUN Ruizhi,DAI Yizhou,et al. Intelligent exhibition platform of Chinese ancient farming virtual scene based on Unity3D[J]. Transactions of the CSAE,2017,33(Supp. 1):308-314.(in Chinese)
[16]吕萌萌,郭新宇,陆声链,等.基于Unity 3D果树交互虚拟修剪技术及其实现[J].农机化研究,2015,37(4):7-11,35.Lü Mengmeng,GUO Xinyu,LU Shenglian,et al. Virtual interactive pruning operation on fruit tree based on Unity3D[J].Journal of Agricultural Mechanization Research,2015,37(4):7-11,35.(in Chinese)
[17]程伯文,郑一力,黄青青,等.基于Unity3D的林木联合采育机虚拟训练系统研究[J].系统仿真学报,2018,30(4):1310-1318.CHENG Bowen,ZHENG Yili,HUANG Qingqing,et al. Forestry felling&cultivation machine virtual training system based on Unity3D[J]. Journal of System Simulation,2018,30(4):1310-1318.(in Chinese)
[18] CHENG Chunming,KANG Li,CAI Saihua,et al. Virtual display and interactive experience platform of farming culture based on Unity3D[J]. IFAC Papers On Line,2018,51(17):637-642.
[19]蒲明辉,吴江.基于ADAMS的甘蔗柔性体模型建模研究[J].系统仿真学报,2009,21(7):1930-1932.PU Minghui,WU Jiang. Study on flexible sugarcane modeling based on ADAMS software[J]. Journal of System Simulation,2009,21(7):1930-1932.(in Chinese)
[20] XIAO B X,GUO X Y,DD X H,et al. An interactive digital design system for corn modeling[J]. Mathematical Computer Modelling,2010,51(11-12):1383-1389.
[21]杜岳峰,毛恩荣,宋正河,等.基于ADAMS的玉米植株收获过程仿真[J/OL].农业机械学报,2012,43(增刊):106-111.DU Yuefeng,MAO Enrong,SONG Zhenghe,et al. Simulation on corn plants in harvesting process based on ADAMS[J/OL].Transactions of the Chinese Society for Agricultural Machinery,2012,43(Supp.):106-111. http:∥www. j-csam. org/jcsam/ch/reader/view_abstract. aspx? file_no=2012s021&flag=1. DOI:10. 6041/j. issn. 1000-1298. 2012. S0. 021.(in Chinese)
[22] GALDOS M V,CERRI C C,CERRI C E P,et al. Simulation of sugarcane residue decomposition and aboveground growth[J]. Plant and Soil,2010,326(1-2):243-259.
[23]马彦华,宣传忠,武佩,等.玉米秸秆振动压缩过程的应力松弛试验[J].农业工程学报,2016,32(19):88-94.MA Yanhua,XUAN Chuanzhong,WU Pei,et al. Experiment on stress relaxation of corn stover during compression with assisted vibration[J]. Transactions of the CSAE,2016,32(19):88-94.(in Chinese)
[24]马云海,张金波,吴亚丽.农业物料学[M].北京:化学工业出版社,2015:26-28.
[25] TANG Liang,SONG Weiguo,HOU Tiancheng,et al. Collision detection of virtual plant based on bounding volume hierarchy:a case study on virtual wheat[J]. Journal of Integrative Agriculture,2018,17(2):306-314.
[26]邹湘军,罗锡文,卢俊,等.虚拟环境下农业移动机器人行为及其仿真建模[J].系统仿真学报,2006,18(增刊2):551-553,562.ZOU Xiangjun,LUO Xiwen,LU Jun,et al. Modeling for behavior and simulation of agriculture mobile robot in virtual environment[J]. Journal of System Simulation,2006,18(Supp. 2):551-553,562.(in Chinese)
[27]罗陆锋,邹湘军,卢清华,等.采摘机器人作业行为虚拟仿真与样机试验[J/OL].农业机械学报,2018,49(5):34-42.LUO Lufeng,ZOU Xiangjun,LU Qinghua,et al. Virtual simulation and prototype test for behavior of robot in picking process[J/OL]. Transactions of the Chinese Society for Agricultural Machinery,2018,49(5):34-42. http:∥www. j-csam. org/jcsam/ch/reader/view_abstract. aspx? file_no=20180504&flag=1. DOI:10. 6041/j. issn. 1000-1298. 2018. 05. 004.(in Chinese)
[28]贺俊林,佟金,胡伟,等.辊型和作业速度对玉米收获机摘穗性能的影响[J].农业机械学报,2006,37(3):46-49.HE Junlin,TONG Jin,HU Wei,et al. Influence of snapping roll type and harvesting speed on 4YW-Q corn harvester[J].Transactions of the Chinese Society for Agricultural Machinery,2006,37(3):46-49.(in Chinese)
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