【摘要】：農(nóng)業(yè)機器人廣泛應(yīng)用于溫室內(nèi)的物料運輸和信息采集,如今隨著國內(nèi)外針對農(nóng)用車輛導(dǎo)航技術(shù)的研究不斷深入,基于溫室非結(jié)構(gòu)化特點的設(shè)施農(nóng)業(yè)作業(yè)車輛行走導(dǎo)航成為研究的關(guān)鍵技術(shù)之一。針對我國溫室壟間空間結(jié)構(gòu)狹小的特點,本文設(shè)計了一種具有協(xié)同作業(yè)及定點巡航功能的磁導(dǎo)式車輛控制系統(tǒng)及裝備,利用磁導(dǎo)航技術(shù)實現(xiàn)作業(yè)車輛在溫室壟間的自主導(dǎo)航,并設(shè)計模糊PID路徑跟蹤算法提高導(dǎo)航精度,并利用MATLAB/Simulink對該控制系統(tǒng)模型進行仿真分析。在磁導(dǎo)航的基礎(chǔ)上,通過加權(quán)融合算法提高測距模塊的測量精度,實現(xiàn)作業(yè)車輛的精準(zhǔn)跟隨;通過磁地標(biāo)傳感器實現(xiàn)車輛在溫室內(nèi)的定點巡航。為了驗證控制系統(tǒng)可行性,本文設(shè)計研制磁導(dǎo)式作業(yè)車輛行走控制系統(tǒng)硬件,并結(jié)合軟件系統(tǒng)的設(shè)計和調(diào)試,在溫室壟間進行試驗驗證。論文主要研究內(nèi)容如下:(1)根據(jù)溫室作業(yè)車輛行走機構(gòu)的性能指標(biāo),采用履帶式行走機構(gòu)實現(xiàn)車輛在溫室壟間的自動導(dǎo)航。針對溫室作業(yè)車輛轉(zhuǎn)向控制問題,提出基于履帶式溫室生境信息采集車輛結(jié)構(gòu),以導(dǎo)航速度和導(dǎo)航過程中磁導(dǎo)航傳感器中心點與預(yù)設(shè)導(dǎo)引路徑的橫向偏差為變量,建立溫室車輛運動模型。。(2)根據(jù)磁導(dǎo)式溫室履帶車輛協(xié)同作業(yè)和定點巡航功能的設(shè)計要求,對車輛控制系統(tǒng)主體結(jié)構(gòu)進行介紹,并對構(gòu)成控制系統(tǒng)的主控制器、磁導(dǎo)航模塊、測距模塊、定位模塊、驅(qū)動模塊、電源模塊進行選型和相關(guān)電路設(shè)計。重點對主控制器模塊和傳感器模塊進行詳細分析和描述,并設(shè)計STC15W4K56S4單片機最小系統(tǒng)電路,其中包括電源電路、時鐘電路和復(fù)位電路。由于控制系統(tǒng)上電時的不穩(wěn)定狀態(tài)或者運行過程中的程序跑偏等情況,通過外部復(fù)位電路手動恢復(fù)控制系統(tǒng)初始化工作狀態(tài)。采用16個霍爾傳感器組成磁信號檢測整列,提高導(dǎo)航信息檢測的穩(wěn)定性問題。在溫室作業(yè)車輛行走控制系統(tǒng)硬件設(shè)計的基礎(chǔ)上,構(gòu)建行走控制系統(tǒng)軟件,從而協(xié)調(diào)各功能模塊的有效運行。針對各功能模塊的實現(xiàn)流程給出磁導(dǎo)式溫室作業(yè)車輛控制系統(tǒng)軟件結(jié)構(gòu),通過C語言在Keil?Vision4開發(fā)環(huán)境下對程序進行編譯。(3)對溫室作業(yè)車輛行走控制系統(tǒng)算法進行設(shè)計和仿真驗證。采用加權(quán)融合算法對測距模塊不同傳感器的測量值進行加權(quán)融合。采用模糊PID算法作為作業(yè)車輛的導(dǎo)航算法,根據(jù)溫室作業(yè)車輛行走系統(tǒng)運動模型,在MATLAB/Simulink平臺中建立作業(yè)車輛路徑跟蹤仿真系統(tǒng),結(jié)果表明:行走控制系統(tǒng)能夠根據(jù)偏差信號,在0.5 s內(nèi)恢復(fù)到穩(wěn)定狀態(tài);當(dāng)系統(tǒng)達到穩(wěn)定狀態(tài)時加入尖峰干擾脈沖信號,系統(tǒng)能夠在0.5s內(nèi)恢復(fù)穩(wěn)定,驗證該算法的可行性和有效性。(4)以履帶式溫室生境信息采集車輛為實驗平臺,在江蘇大學(xué)溫室進行導(dǎo)航試驗。試驗結(jié)果表明:在溫室壟間地面,當(dāng)行駛速度為1 m/s時,作業(yè)車輛的人機跟隨距離誤差小于5 cm;當(dāng)車輛的行駛速度為0.4-1 m/s時,在定點巡航試驗中,駐車后車輛中心與設(shè)定的生境信息監(jiān)測點的距離不超過0.3 cm;當(dāng)作業(yè)車輛行駛速度為1m/s時,5 m內(nèi)的直線段導(dǎo)航橫向誤差小于2.6 cm;當(dāng)車輛在溫室壟頭以半徑為0.75m實現(xiàn)圓曲線路徑跟蹤,作業(yè)車輛的行駛速度不超過0.3m/s時,路徑跟蹤的最大橫向偏差為2.7 cm。試驗結(jié)果驗證控制算法具有較好的魯棒性與實時性。
[Abstract]:The agricultural robot is widely used in the material transportation and information collection in the greenhouse, and now, with the development of the navigation technology of the agricultural vehicle at home and abroad, the vehicle walking navigation based on the non-structural characteristics of the greenhouse has become one of the key technologies of the research. Aiming at the characteristics of the narrow space structure of the greenhouse in China, a magnetic guided vehicle control system and equipment with a cooperative operation and a fixed-point cruise function are designed, and the autonomous navigation of the working vehicle in the greenhouse is realized by using the magnetic navigation technology, And the fuzzy PID path tracking algorithm is designed to improve the navigation precision, and the control system model is simulated and analyzed by using MATLAB/ Simulink. On the basis of magnetic navigation, the measurement accuracy of the ranging module is improved by a weighted fusion algorithm, and the accurate follow-up of the operation vehicle is realized; and the fixed-point cruise of the vehicle in the greenhouse is realized through the magnetic landmark sensor. In order to verify the feasibility of the control system, the hardware of the running control system of the magnetic conduction type working vehicle is designed and developed, and the design and debugging of the software system are combined, and the test verification is carried out between the green houses. The main contents of this paper are as follows: (1) According to the performance index of the vehicle running mechanism of the greenhouse, the crawler-type walking mechanism is adopted to realize the automatic navigation of the vehicle in the greenhouse. In view of that problem of vehicle steering control for greenhouse operation, a vehicle structure is proposed based on the information acquisition of the crawler-type greenhouse habitat, and the model of the greenhouse vehicle motion is established by using the lateral deviation of the center point of the magnetic navigation sensor and the preset guide path in the navigation speed and the navigation process as a variable. (2) the main controller, the magnetic navigation module, the distance measuring module, the positioning module and the driving module which form the control system are introduced according to the design requirements of the collaborative operation of the magnetic guide type greenhouse track vehicle and the fixed-point cruise function, the main controller, the magnetic navigation module, the distance measuring module, the positioning module and the driving module which form the control system are provided, The power module is selected and the relevant circuit design is involved. The main controller module and the sensor module are analyzed and described in detail, and the minimum system circuit of the STC15W4K56S4 single-chip computer is designed, including the power supply circuit, the clock circuit and the reset circuit. The operation state of the control system is manually restored by the external reset circuit due to the unstable state at the power-up of the control system or the deviation of the program during operation. And 16 Hall sensors are adopted to form a magnetic signal detection whole column, and the stability problem of the navigation information detection is improved. On the basis of the hardware design of the walking control system of the greenhouse operation vehicle, the software of the walking control system is constructed, so as to coordinate the effective operation of the functional modules. The software structure of the control system of the magnetically guided greenhouse is given according to the realization flow of each function module, and the program is compiled by the C language in the development environment of the Keil? Vision4. And (3) carrying out design and simulation verification on the walking control system algorithm of the greenhouse operation vehicle. And the weighted fusion algorithm is adopted to carry out weighted fusion on the measured values of different sensors of the ranging module. The fuzzy PID algorithm is used as the navigation algorithm of the working vehicle. According to the motion model of the vehicle running system of the greenhouse, the simulation system for the track of the working vehicle is established in the MATLAB/ Simulink platform. The results show that the walking control system can recover to the stable state within 0.5s according to the deviation signal. When the system reaches a stable state, a spike interference pulse signal is added, so that the system can recover the stability within 0.5 s, and the feasibility and the effectiveness of the algorithm can be verified. And (4) collecting the vehicle as an experimental platform by using the crawler-type greenhouse habitat information acquisition vehicle, and performing navigation test on the greenhouse of the university of Jiangsu. The test results show that when the running speed is 1 m/ s, the man-machine follow-distance error of the working vehicle is less than 5 cm when the running speed is 1 m/ s, and when the running speed of the vehicle is 0.4-1 m/ s, in the fixed-point cruise test, the distance between the center of the parking rear vehicle and the set habitat information monitoring point is not more than 0.3 cm; when the running speed of the working vehicle is 1 m/ s, the horizontal error of the straight segment navigation in the 5m is less than 2.6cm; when the vehicle is in the greenhouse, the circular curve path tracking is realized at the radius of 0.75m, When the running speed of the working vehicle is not more than 0.3 m/ s, the maximum lateral deviation of the path tracking is 2.7 cm. The test result verification control algorithm has good robustness and real-time performance.
【學(xué)位授予單位】：江蘇大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：S22

【參考文獻】

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1 汪小e，

本文編號：2460427