小型履带式油菜播种机导航免疫PID控制器设计
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摘要
针对适应于长江中下游地区稻茬田土壤黏湿、小田块的轻简化播种机智能化问题,设计了一种基于免疫PID的小型履带式油菜播种机导航控制器。以小型履带式油菜播种机为基础,利用电磁铁对其转向系统进行电控改装,采用高精度北斗定位模块和电子罗盘进行组合导航,获取履带式播种机的位置和航向信息作为导航控制器的输入,设计了小型履带式油菜播种机自动导航控制系统。建立了履带式油菜播种机运动学模型和转向角传递函数,利用Matlab仿真和实地导航试验对常规PID控制和免疫PID控制进行了对比试验。仿真表明:在相同参数条件下,与常规PID相比,免疫PID控制具有响应快、超调量小、平均跟踪误差小等特点;路面试验表明:当播种机速度为0.50m/s时,免疫PID控制器直线跟踪的平均绝对偏差为4.2 cm,最大跟踪偏差为11.9 cm。田间试验表明:当播种机速度为0.50 m/s时,免疫PID控制器直线跟踪平均绝对偏差为5.8 cm,最大偏差不超过15.2 cm,能够较好地满足播种机导航作业要求,该研究可为履带式播种机的自主导航提供了技术参考。
The middle and lower reaches of the Yangtze River are the main producing areas of winter rapeseed in China. However, due to the effects of harvesting agricultural crops, heavy soil compaction, small field, the mechanization level of rapeseed is low. The level of intelligent seeding needs to be improved. In this paper, a navigation controller for small crawler-type seeder based on immune PID was designed to solve the problem of intelligent seeding in the middle and lower reaches of the Yangtze River where the soil is sticky, the field is small. The small crawler-type rape seeder automatic navigation control system was designed. It used the small crawler-type rape seeder as the platform, and its steering system was modified by electromagnet. The high-precision BeiDou positioning module and the electronic compass was used for combined navigation to obtain the position and heading information of the crawler-type rape seeder as the input of the navigation controller. The immune PID controller was a nonlinear P controller that could adjust the proportional coefficient according to the feedback in real time. The control process was as follows. First, the plane coordinates of the start and end points of the straight path to be tracked were artificially set, and the main controller automatically calculated the distance of the target heading the start point and the end point. The weighted average algorithm was used to filter the longitude and latitude coordinates collected four times to get the current position. The controller calculated the distance deviation from the current position to the set route by the point-to-line distance formula. Taking the filtered distance deviation as an input, the target heading was calculated using the target heading correction formula distance deviation. Then, the course deviation(the deviation between the corrected target heading and the heading acquired by the electronic compass in real time) was used as an input of the immune PID controller, and the immune PID controller determined the Duty Ratio as the output u to act on the steering mechanism, achieving control of the steering of the track-type seeder. In addition, according to the characteristics of the tracked vehicle, the steering of the small crawler-type rape seeder was analyzed, and its steering model and steering angle transfer function were established. The immune PID controller was verified by Matlab simulation and experiment. Under the same parameters, the simulation showed that, compared with the conventional PID control, the immune PID control had the characteristics of fast response, small overshoot and small average tracking error. The pavement experiment showed that when the vehicle speed was 0.50 m/s, the average absolute deviation of the linear tracking of the immune PID controller was 4.2 cm, and the maximum deviation was not more than 11.9 cm. The field experiment showed that when the vehicle speed was 0.50 m/s, the average absolute deviation of the linear tracking of the immune PID controller was 5.8 cm, and the maximum deviation was not more than 15.2 cm, which was 32.6% and 18.1% higher than the conventional PID. It could better meet the requirements of the seeder navigation operation. This research provides a technical reference for the autonomous navigation of the crawler-type rape seeder.
The middle and lower reaches of the Yangtze River are the main producing areas of winter rapeseed in China. However, due to the effects of harvesting agricultural crops, heavy soil compaction, small field, the mechanization level of rapeseed is low. The level of intelligent seeding needs to be improved. In this paper, a navigation controller for small crawler-type seeder based on immune PID was designed to solve the problem of intelligent seeding in the middle and lower reaches of the Yangtze River where the soil is sticky, the field is small. The small crawler-type rape seeder automatic navigation control system was designed. It used the small crawler-type rape seeder as the platform, and its steering system was modified by electromagnet. The high-precision BeiDou positioning module and the electronic compass was used for combined navigation to obtain the position and heading information of the crawler-type rape seeder as the input of the navigation controller. The immune PID controller was a nonlinear P controller that could adjust the proportional coefficient according to the feedback in real time. The control process was as follows. First, the plane coordinates of the start and end points of the straight path to be tracked were artificially set, and the main controller automatically calculated the distance of the target heading the start point and the end point. The weighted average algorithm was used to filter the longitude and latitude coordinates collected four times to get the current position. The controller calculated the distance deviation from the current position to the set route by the point-to-line distance formula. Taking the filtered distance deviation as an input, the target heading was calculated using the target heading correction formula distance deviation. Then, the course deviation(the deviation between the corrected target heading and the heading acquired by the electronic compass in real time) was used as an input of the immune PID controller, and the immune PID controller determined the Duty Ratio as the output u to act on the steering mechanism, achieving control of the steering of the track-type seeder. In addition, according to the characteristics of the tracked vehicle, the steering of the small crawler-type rape seeder was analyzed, and its steering model and steering angle transfer function were established. The immune PID controller was verified by Matlab simulation and experiment. Under the same parameters, the simulation showed that, compared with the conventional PID control, the immune PID control had the characteristics of fast response, small overshoot and small average tracking error. The pavement experiment showed that when the vehicle speed was 0.50 m/s, the average absolute deviation of the linear tracking of the immune PID controller was 4.2 cm, and the maximum deviation was not more than 11.9 cm. The field experiment showed that when the vehicle speed was 0.50 m/s, the average absolute deviation of the linear tracking of the immune PID controller was 5.8 cm, and the maximum deviation was not more than 15.2 cm, which was 32.6% and 18.1% higher than the conventional PID. It could better meet the requirements of the seeder navigation operation. This research provides a technical reference for the autonomous navigation of the crawler-type rape seeder.
引文
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[4]胡静涛,高雷,白晓平,等.农业机械自动导航技术研究进展[J].农业工程学报,2015,31(10):1-10.Hu Jingtao,Gao Lei,Bai Xiaoping,et al.Advances in research on automatic navigation technology for agricultural machinery[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2015,31(10):1-10.(in Chinese with English abstract)
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[8]王旭.轮式和履带式拖拉机适应性对比分析[J].拖拉机与农用运输车,2006(1):1-2,23.Wang Xu.Comparative analysis of wheeled and crawler tractors[J].Tractors&Farming Vehicles,2006(1):1-2,23.(in Chinese with English abstract)
[9]Yamauchi G,Nagatani K,Hashimoto T.Slip-compensated odometry for tracked vehicle on loose and weak slope[J].Robomech Journal,2017,4(1):27.
[10]Endo D,Okada Y,Nagatani K,et al.Path following control for tracked vehicles based on slip-compensating odometry[C]//Intelligent Robots and Systems,2007.IROS2007.IEEE/RSJ International Conference on.IEEE,2007.
[11]王吉林.智能履带车视觉导航技术研究[D].长春:吉林大学,2004.Wang Jilin.Research on Visual Navigation Technology of Intelligent Tracked Vehicle[D].Changchun:Jilin University,2004.(in Chinese with English abstract)
[12]付拓,毛文华,张小超,等.一种履带拖拉机自动导航转向控制方法[J].农业工程,2018,8(1):84-88.Fu Tuo,Mao Wenhua,Zhang Xiaochao,et al.An autonavigation steering control method for crawler tractors[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2018,8(1):84-88.(in Chinese with English abstract)
[13]李剑峰,范知友,范凤鸣.履带车辆运动阻力系数及行动系统效率分析[J].车辆与动力技术,2015(3):1-4.Li Jianfeng,Fan Zhiyou,Fan Fengming.Analysis of moving resistance coefficient and moving system efficiency of tracked vehicle[J].Vechicle&Power Technology,2015(3):1-4.(in Chinese with English abstract)
[14]Urrea C,Munoz J.Path tracking of mobile robot in crops[J].Journal of Intelligent&Robotic Systems,2015,80(2):193-205.
[15]Farooq U,Hasan K M,Hanif A,et al.Fuzzy logic based path tracking controller for wheeled mobile robots[J].International Journal of Computer&Electrical Engineering,2014,6(2):145-150.
[16]Zakaria M A,Zamzuri H,Mazlan S A.Vehicle path tracking using future prediction steering control[J].Procedia Engineering,2012,41:473-479.
[17]Breivik M,Hovstein V E,Fossen T I.Straight-line target tracking for unmanned surface vehicles[J].Modeling Identification&Control,2008,29(4):131-149.
[18]Marino R,Scalzi S,Netto M.Nested PID steering control for lane keeping in autonomous vehicles[J].Control Engineering Practice,2011,19(12):1459-1467.
[19]Takai R,Yang L,Noguchi N.Development of a crawler-type robot tractor using RTK-GPS and IMU[J].Engineering in Agriculture,Environment and Food,2014,7(4):143-147.
[20]王纪伟,陈刚,汪俊.基于模糊免疫PID的驾驶机器人车辆路径及速度跟踪控制[J].南京理工大学学报,2017,41(6):686-692.Wang Jiwei,Chen Gang,Wang Jun.Path and speed tracking control of driving robot based on fuzzy immune PID[J].Journal of Nanjing University of Science and Technology,2017,41(6):686-692.(in Chinese with English abstract)
[21]张智刚,罗锡文,周志艳,等.久保田插秧机的GPS导航控制系统设计[J].农业机械学报,2006,37(7):95-97,82.Zhang Zhigang,Luo Xiwen,Zhou Zhiyan,et al.Design of gps navigation control system for kubota rice transplanter[J].Transactions of the Chinese Society of Agricultural Machinery,2006,37(7):95-97,82.(in Chinese with English abstract)
[22]熊中刚,叶振环,贺娟,等.基于免疫模糊PID的小型农业机械路径智能跟踪控制[J].机器人,2015,37(2):212-223.Xiong Zhonggang,Ye Zhenhuan,He Juan,et al.Intelligent path tracking control of small agricultural machinery based on immune fuzzy PID[J].Robot,2015,37(2):212-223.(in Chinese with English abstract)
[23]罗锡文,张智刚,赵祚喜,等.东方红X-804拖拉机的DGPS自动导航控制系统[J].农业工程学报,2009,25(11):139-145.Luo Xiwen,Zhang Zhigang,Zhao Zuoxi,et al.Design of GPS navigation control system for Dong fang hong X-804tractor[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2009,25(11):139-145.(in Chinese with English abstract).
[24]丁幼春,詹鹏,周雅文,等.北斗定位田间信息采集平台运动控制器设计与试验[J].农业工程学报,2017,33(12):178-185.Ding Youchun,Zhan Peng,Zhou Yawen,et al.Motion controller design and experiment of BeiDou positioning field information collection platform[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2017,33(12):178-185.(in Chinese with English abstract)
[25]丁幼春,廖庆喜,黄海东,等.联合收获机大曲率路径视觉导航方法[J].农业机械学报,2011,42(增刊1):122-127.Ding Youchun,Liao Qingxi,Huang Haidong,et al.Vision navigation method for large curvature path of combine harvester[J].Transactions of the Chinese Society for Agricultural Machinery,2011,42(Supp.1):122-127.(in Chinese with English abstract)
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