胡 煉，王志敏，汪 沛，何 杰，焦晉康，王晨陽(yáng)，李明錦

·農(nóng)業(yè)裝備工程與機(jī)械化·

基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)

胡 煉1,2，王志敏1，汪 沛1,2※，何 杰1,2，焦晉康1，王晨陽(yáng)1，李明錦1

（1. 華南農(nóng)業(yè)大學(xué)南方農(nóng)業(yè)機(jī)械與裝備關(guān)鍵技術(shù)教育部重點(diǎn)實(shí)驗(yàn)室，廣州 510642； 2.嶺南現(xiàn)代農(nóng)業(yè)科學(xué)與技術(shù)廣東省實(shí)驗(yàn)室茂名分中心，茂名 525000）

為解決基于全球?qū)Ш叫l(wèi)星系統(tǒng)（global navigation satellite system，GNSS）的農(nóng)業(yè)機(jī)器人和自動(dòng)駕駛農(nóng)機(jī)在機(jī)庫(kù)、大棚等衛(wèi)星信號(hào)弱或無(wú)環(huán)境下定位精度低甚至無(wú)法定位的問題，該研究提出了基于激光感知的農(nóng)業(yè)機(jī)器人定位方法。采用二維激光雷達(dá)和激光接收器設(shè)計(jì)了基于激光感知的機(jī)器人定位系統(tǒng)，通過二維激光雷達(dá)發(fā)射掃描激光獲取機(jī)器人上激光接收器的點(diǎn)云，同時(shí)激光接收器感應(yīng)掃描激光，融合感應(yīng)掃描激光時(shí)間差和激光接收器點(diǎn)云特征，得到移動(dòng)激光接收器（即農(nóng)業(yè)機(jī)器人）的定位。以全站儀測(cè)量為參照在大棚內(nèi)開展驗(yàn)證試驗(yàn)，結(jié)果表明，在激光雷達(dá)掃描范圍內(nèi)，機(jī)器人行駛速度為0.8 m/s時(shí)，直線行駛時(shí)最大偏差絕對(duì)平均值為4.1 cm，最大均方根誤差為1.5 cm；曲線行駛時(shí)最大偏差絕對(duì)平均值為6.2 cm，最大均方根誤差為2.6 cm，滿足農(nóng)業(yè)機(jī)器人在農(nóng)機(jī)庫(kù)等環(huán)境中自動(dòng)導(dǎo)航所需定位精度要求。

機(jī)器人；激光雷達(dá)；激光傳感；定位；智能農(nóng)機(jī)裝備

0 引 言

農(nóng)業(yè)機(jī)器人通常應(yīng)用于結(jié)構(gòu)化場(chǎng)景與隨機(jī)的不確定場(chǎng)景，且作業(yè)任務(wù)日益復(fù)雜[1]，定位和導(dǎo)航是農(nóng)業(yè)機(jī)器人的關(guān)鍵技術(shù)[2]。當(dāng)前農(nóng)機(jī)自動(dòng)駕駛技術(shù)和農(nóng)機(jī)輔助導(dǎo)航技術(shù)快速發(fā)展[3-7]，通過物聯(lián)網(wǎng)、大數(shù)據(jù)和人工智能等先進(jìn)信息技術(shù)的聯(lián)合使用，農(nóng)機(jī)自動(dòng)駕駛和輔助導(dǎo)航技術(shù)已在無(wú)人化智慧農(nóng)場(chǎng)開始實(shí)踐應(yīng)用[8]。

全球?qū)Ш叫l(wèi)星系統(tǒng)（global navigation satellite system，GNSS）作為農(nóng)業(yè)機(jī)械智能化技術(shù)中的一項(xiàng)關(guān)鍵技術(shù)，近年來(lái)已被廣泛應(yīng)用于農(nóng)業(yè)生產(chǎn)各環(huán)節(jié)，其定位精度達(dá)到厘米級(jí)[9]，基于GNSS的農(nóng)業(yè)機(jī)械導(dǎo)航系統(tǒng)旱地作業(yè)直線路徑跟蹤精度優(yōu)于±2.5 cm[4]，水田作業(yè)直線路徑跟蹤橫向偏差平均值為4.3 cm[10]。因此，智能農(nóng)機(jī)依靠GNSS定位實(shí)現(xiàn)了大田高精度智能化無(wú)人作業(yè)[11]，但在農(nóng)機(jī)機(jī)庫(kù)、農(nóng)機(jī)轉(zhuǎn)移行駛過程中經(jīng)過樹冠下和高架橋橋底以及溫室大棚設(shè)施等場(chǎng)景時(shí)，存在GNSS衛(wèi)星信號(hào)差或丟失的問題，難以實(shí)現(xiàn)導(dǎo)航定位，因此亟需其他定位方法融合補(bǔ)充。

Wi-fi、Zigbee、藍(lán)牙和超寬帶等無(wú)線通信技術(shù)[12]以及即時(shí)定位與地圖構(gòu)建（simultaneous localization and mapping，SLAM）技術(shù)是常用定位方法。無(wú)線通信技術(shù)中Wi-fi、超寬帶信號(hào)定位易受環(huán)境因素干擾[12-13]，Zigbee和藍(lán)牙定位需要鋪設(shè)大量設(shè)備[14]。SLAM指在沒有環(huán)境先驗(yàn)信息下，通過使用各種傳感器采集環(huán)境信息，在運(yùn)動(dòng)過程中構(gòu)建環(huán)境地圖，并估計(jì)機(jī)器人位置[15]，目前，已經(jīng)有許多解決SLAM問題的數(shù)學(xué)模型與理論基礎(chǔ)[16]。SLAM技術(shù)包括視覺SLAM和激光SLAM，可以提供載體的相對(duì)位置信息，定位精度較高，已在物流、工業(yè)、醫(yī)療、安防、服務(wù)和農(nóng)業(yè)等移動(dòng)機(jī)器人以及無(wú)人駕駛領(lǐng)域廣泛應(yīng)用[17-21]。在農(nóng)業(yè)機(jī)器人出庫(kù)入庫(kù)時(shí)，因庫(kù)內(nèi)外光照強(qiáng)度差異大，易導(dǎo)致視覺SLAM定位誤差增大甚至無(wú)法定位，而且圖像處理的運(yùn)算量大、實(shí)時(shí)性較差[2,22]。此外，當(dāng)環(huán)境中有較多移動(dòng)物體時(shí)，視覺SLAM的環(huán)境地圖構(gòu)建偏差增大，定位精度降低[23]。相比之下，激光SLAM技術(shù)較成熟、定位誤差更小[24]，但激光SLAM構(gòu)建的地圖缺乏語(yǔ)義信息[25]，對(duì)于大場(chǎng)景非固定地圖仍需進(jìn)一步研究[26]，激光SLAM的地圖構(gòu)建可使用二維激光雷達(dá)和三維激光雷達(dá)，目前在物流和工業(yè)等領(lǐng)域主要使用成本較高的三維激光雷達(dá)[27]。

在無(wú)人化農(nóng)場(chǎng)作業(yè)中，若每臺(tái)無(wú)人駕駛農(nóng)機(jī)均配備一套激光SLAM系統(tǒng)和高性能運(yùn)算處理器實(shí)現(xiàn)小范圍衛(wèi)星信號(hào)被遮擋區(qū)域內(nèi)的無(wú)人駕駛農(nóng)機(jī)定位，不僅不能充分利用激光SLAM系統(tǒng)性能，而且增加了成本。因此，在保持現(xiàn)有農(nóng)機(jī)無(wú)人駕駛系統(tǒng)定位解算算法等前提下，研究能夠和GNSS系統(tǒng)融合補(bǔ)充的定位系統(tǒng)來(lái)解決無(wú)人駕駛農(nóng)機(jī)出入庫(kù)衛(wèi)星信號(hào)弱或無(wú)的問題，對(duì)無(wú)人化農(nóng)場(chǎng)的研究與建設(shè)具有重要意義。故本文設(shè)計(jì)了基于二維激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)，并進(jìn)行定位試驗(yàn)驗(yàn)證其定位精度。

1 基于激光感知的農(nóng)業(yè)機(jī)器人定位方法

1.1 基于激光感知的農(nóng)業(yè)機(jī)器人定位原理

基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)由移動(dòng)激光接收器、處理器、固定激光接收器和二維激光雷達(dá)組成，如圖1所示，移動(dòng)激光接收器和處理器安裝在機(jī)器人上，固定激光接收器和二維激光雷達(dá)固定在已知大地坐標(biāo)位置，根據(jù)大地坐標(biāo)點(diǎn)及激光雷達(dá)坐標(biāo)系與大地坐標(biāo)系的位置關(guān)系，基于激光感知的定位算法計(jì)算得到機(jī)器人的大地坐標(biāo)，因此現(xiàn)有農(nóng)機(jī)無(wú)人駕駛系統(tǒng)的定位解算和控制算法均無(wú)需修改即可實(shí)現(xiàn)無(wú)GNSS信號(hào)時(shí)實(shí)現(xiàn)定位和導(dǎo)航，例如，機(jī)器人出庫(kù)時(shí)，在既有基于激光感知的機(jī)器人定位系統(tǒng)定位信號(hào)又有GNSS信號(hào)的區(qū)域切換GNSS定位系統(tǒng)進(jìn)行導(dǎo)航，而入庫(kù)時(shí)，在該區(qū)域切換采用基于激光感知的機(jī)器人定位系統(tǒng)進(jìn)行導(dǎo)航。

圖1 基于激光感知的農(nóng)業(yè)機(jī)器人定位原理示意圖

1.2 基于激光感知的農(nóng)業(yè)機(jī)器人定位算法

激光雷達(dá)以一定周期掃描獲得數(shù)量已知且排序固定的點(diǎn)云數(shù)據(jù)，固定激光接收器感應(yīng)激光雷達(dá)周期性照射產(chǎn)生固定激光信號(hào)，且固定激光接收器位置已知，機(jī)器人運(yùn)動(dòng)過程中移動(dòng)激光接收器感應(yīng)激光雷達(dá)周期性照射產(chǎn)生移動(dòng)激光信號(hào)，在一個(gè)掃描周期中，根據(jù)固定激光信號(hào)與移動(dòng)激光信號(hào)得到兩者的觸發(fā)時(shí)間差，由此獲得照射到移動(dòng)激光接收器的激光射線與照射到固定激光接收器的激光射線夾角Δ，以此快速準(zhǔn)確找到移動(dòng)激光接收器在激光雷達(dá)點(diǎn)云中的散點(diǎn)集，結(jié)合點(diǎn)云特征匹配算法獲得移動(dòng)激光接收器中心坐標(biāo)，最后通過坐標(biāo)轉(zhuǎn)換得到移動(dòng)激光接收器中心在大地坐標(biāo)系中的位置，即農(nóng)業(yè)機(jī)器人在大地坐標(biāo)系中的位置。

在激光雷達(dá)掃描平面建立以激光雷達(dá)為圓心的極坐標(biāo)系和直角坐標(biāo)系，極坐標(biāo)系中任意點(diǎn)（，），其直角坐標(biāo)系為（，），坐標(biāo)轉(zhuǎn)換關(guān)系如下：

由激光接收器光電轉(zhuǎn)換模塊中心坐標(biāo)推算出移動(dòng)激光接收器中心坐標(biāo)，再轉(zhuǎn)換至大地坐標(biāo)系下移動(dòng)激光接收器中心坐標(biāo)，即定位坐標(biāo)。

注：為接收器外殼長(zhǎng)邊長(zhǎng)度，cm；為接收器外殼短邊長(zhǎng)度，cm；0為接收器感光模塊距外殼短邊距離，cm；0為接收器感光模塊距外殼長(zhǎng)邊距離，cm；為接收器感光模塊與坐標(biāo)原點(diǎn)連線；1為擬合出的接收器外殼長(zhǎng)邊所在直線；3為擬合出的接收器外殼短邊所在直線，點(diǎn)為直線1和直線3的交點(diǎn)；2為接收器感光模塊與點(diǎn)連線；、1、2和3分別為直線1、2和3的斜率；1、2和3分別為直線1、2和3的截距。l為離光電轉(zhuǎn)換模塊中心最近的激光雷達(dá)掃描射線，θ為激光雷達(dá)射線l掃描線對(duì)應(yīng)極坐標(biāo)的角度值。

Note:is the length of the long side of the mobile laser receiver housing, cm;is the length of the short side of the mobile laser receiver housing, cm;0is the distance from the photosensitive module of the mobile laser receiver to the short side of the housing, cm;0is the distance from the photosensitive module of the mobile laser receiver to the long side of the housing, cm; theis the connection line between the receiver photosensitive module and the coordinate origin, the1is the fitting line of the receiver housing on long side , pointis the intersection of line1and line3,2is the connection line between the photosensitive module of the mobile laser receiver and point, the3is the fitting line of the receiver housing on short side,,1,2and3is the slope of the straight line,1,2and3, respectively;1is the intercept of the straight line1,1is the intercept of the straight line2,3is the intercept of the straight line3, thelis the closest laser radar scanning ray to the center of the photoelectric conversion module,θis the angle value of the polar coordinate corresponding to the scanning line of the laser radar rayl.

圖2 激光接收器光電轉(zhuǎn)換模塊中心坐標(biāo)幾何關(guān)系示意圖

Fig.2 Schematic diagram of the central coordinate geometric relationship of the photoelectric conversion module of the laser receiver

2 基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)試驗(yàn)

2.1 系統(tǒng)介紹

基于激光感知的農(nóng)業(yè)機(jī)器人定位（ARPLS）系統(tǒng)如圖3所示，以東風(fēng)井關(guān)T954拖拉機(jī)為試驗(yàn)平臺(tái)。ARPLS系統(tǒng)硬件部分主要由移動(dòng)端和固定端組成，移動(dòng)端包括移動(dòng)激光接收器，固定端包括激光雷達(dá)和固定激光接收器。激光接收器通過濾光模塊、光電轉(zhuǎn)換模塊、信號(hào)調(diào)制模塊將激光雷達(dá)發(fā)射的光信號(hào)轉(zhuǎn)換成電信號(hào)[28]，數(shù)據(jù)處理與通信傳輸模塊將激光感應(yīng)信號(hào)通過CAN總線進(jìn)行傳輸，激光接收器外殼長(zhǎng)邊11 cm，短邊6.5 cm。移動(dòng)激光接收器安裝在拖拉機(jī)頂部機(jī)體（沿機(jī)頭方向）中心線上，離地高度3 m，激光雷達(dá)和固定接收器固定在華南農(nóng)業(yè)大學(xué)增城教學(xué)科研基地農(nóng)機(jī)庫(kù)支撐柱上，且移動(dòng)激光接收器和固定激光接收器均能夠接收到激光雷達(dá)發(fā)射的激光射線。移動(dòng)激光接收器和固定激光接收器的CAN總線通過PCAN-USB傳輸?shù)教幚砥?，PCAN-USB用于監(jiān)聽CAN 網(wǎng)絡(luò)消息，時(shí)間戳的分辨率為42 μs。激光雷達(dá)的測(cè)量距離為40～20 000 mm，掃描范圍為270°，角度分辨率為0.117 2°，掃描頻率為10 Hz，誤差為測(cè)量距離的1%。

圖3 安裝在拖拉機(jī)上的基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)

使用Visual studio 2022通過C#編程語(yǔ)言編寫系統(tǒng)軟件，采用多線程數(shù)據(jù)事件觸發(fā)的方式進(jìn)行數(shù)據(jù)處理與分析，得到準(zhǔn)確的激光雷達(dá)、移動(dòng)激光接收器和固定激光接收器的數(shù)據(jù)響應(yīng)時(shí)間戳，固定端數(shù)據(jù)發(fā)送到移動(dòng)端進(jìn)行分析處理，從而實(shí)時(shí)獲得定位數(shù)據(jù)。

試驗(yàn)以全站儀和RTK GNSS系統(tǒng)的測(cè)量軌跡作為參考對(duì)象，且均采用WGS-84坐標(biāo)系。全站儀自動(dòng)跟蹤安裝在移動(dòng)激光接收器上的棱鏡，進(jìn)行動(dòng)態(tài)跟蹤測(cè)量，全站儀為L(zhǎng)eica Ms60，測(cè)量頻率10 Hz，100 m范圍內(nèi)測(cè)量誤差1 mm；RTK GNSS系統(tǒng)直接測(cè)量獲取拖拉機(jī)定位，RTK GNSS板卡為K728，測(cè)量頻率10 Hz，平面定位精度1 cm。

試驗(yàn)時(shí)拖拉機(jī)在激光雷達(dá)掃描范圍內(nèi)以0.3、0.5和0.8 m/s分別進(jìn)行往復(fù)的直線運(yùn)動(dòng)和曲線運(yùn)動(dòng)，行駛距離9～20 m，每組試驗(yàn)重復(fù)5次，ARPLS系統(tǒng)、全站儀和GNSS三套定位系統(tǒng)同時(shí)采集定位數(shù)據(jù)，采集時(shí)長(zhǎng)3～5 min，其中激光感知定位系統(tǒng)每次試驗(yàn)獲得定位點(diǎn)2 000個(gè)以上。

2.2 坐標(biāo)系轉(zhuǎn)換與機(jī)器人中心定位

3 結(jié)果與分析

ARPLS系統(tǒng)、全站儀和GNSS測(cè)量的一組拖拉機(jī)以0.8 m/s速度直線行駛和曲線行駛的軌跡分別如圖4和圖5所示，其中直線行駛距離10 m、曲線行駛距離12 m。由圖可知，ARPLS系統(tǒng)測(cè)量的拖拉機(jī)軌跡與全站儀和GNSS測(cè)量的軌跡基本重合，表明在試驗(yàn)行駛距離范圍內(nèi)，ARPLS系統(tǒng)提供了試驗(yàn)拖拉機(jī)在WGS-84坐標(biāo)系下的定位。

ARPLS系統(tǒng)動(dòng)態(tài)測(cè)量拖拉機(jī)以0.8 m/s速度進(jìn)行直線行駛和曲線行駛定位與全站儀測(cè)量定位的偏差絕對(duì)值曲線分別如圖6和圖7所示。在相同速度下，直線行駛定位的偏差絕對(duì)值明顯小于曲線行駛定位的偏差絕對(duì)值，因此，ARPLS系統(tǒng)動(dòng)態(tài)測(cè)量直線運(yùn)動(dòng)定位精度高于曲線運(yùn)動(dòng)定位精度，測(cè)量直線運(yùn)動(dòng)定位偏差不大于7 cm，測(cè)量曲線運(yùn)動(dòng)定位偏差小于12 cm。

圖4 拖拉機(jī)直線行駛軌跡

圖5 拖拉機(jī)曲線行駛軌跡

圖6 直線行駛的定位偏差絕對(duì)值曲線

圖7 曲線行駛的定位偏差絕對(duì)值曲線

以全站儀測(cè)量定位為真值，各試驗(yàn)組次ARPLS系統(tǒng)相對(duì)全站儀測(cè)量定位的偏差絕對(duì)平均值和均方根誤差如表1所示。表中試驗(yàn)數(shù)據(jù)表明，隨著拖拉機(jī)速度越快，ARPLS系統(tǒng)定位相對(duì)全站儀定位的誤差隨之增大；行駛速度相同時(shí)，曲線行駛比直線行駛定位的誤差大。0.8 m/s速度時(shí)，直線行駛時(shí)最大偏差絕對(duì)平均值為4.1 cm，最大均方根誤差為1.5 cm；曲線行駛時(shí)最大偏差絕對(duì)平均值為6.2 cm，最大均方根誤差為2.6 cm。

表1 激光感知定位相比全站儀定位誤差

ARPLS系統(tǒng)的誤差主要源于移動(dòng)激光接收器和固定激光接收器感知激光的時(shí)間差誤差以及點(diǎn)云擬合誤差。隨著拖拉機(jī)速度增加而定位誤差增大是由于激光雷達(dá)需要完成一圈掃描才能輸出點(diǎn)云數(shù)據(jù)，導(dǎo)致定位系統(tǒng)數(shù)據(jù)輸出與測(cè)量時(shí)刻存在延時(shí)。曲線行駛定位誤差比直線行駛定位誤差大主要是因?yàn)榍€運(yùn)動(dòng)導(dǎo)致激光接收器長(zhǎng)方形外殼的長(zhǎng)邊或短邊點(diǎn)云數(shù)量少甚至沒有，從而降低了算法推算精度。

4 結(jié) 論

1）本文提出了基于激光感知的農(nóng)業(yè)機(jī)器人定位方法，利用激光感知和激光雷達(dá)點(diǎn)云特征得到移動(dòng)激光接收器相對(duì)固定激光雷達(dá)的位置，通過坐標(biāo)轉(zhuǎn)換獲得機(jī)器人的實(shí)時(shí)大地定位坐標(biāo)。

2）基于激光感知的定位算法解決了難以從二維激光雷達(dá)點(diǎn)云中確定目標(biāo)對(duì)象點(diǎn)云的問題，通過固定激光信號(hào)與移動(dòng)激光信號(hào)觸發(fā)時(shí)間差快速準(zhǔn)確找到移動(dòng)激光接收器在激光雷達(dá)點(diǎn)云中的散點(diǎn)集，結(jié)合點(diǎn)云特征匹配算法實(shí)現(xiàn)了快速準(zhǔn)確地獲得目標(biāo)對(duì)象定位。

3）設(shè)計(jì)了基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)，大棚內(nèi)試驗(yàn)結(jié)果表明，在激光雷達(dá)掃描范圍內(nèi)，機(jī)器人行駛速度為0.8 m/s時(shí)，直線行駛時(shí)最大偏差絕對(duì)平均值為4.1 cm，最大均方根誤差為1.5 cm；曲線行駛時(shí)最大偏差絕對(duì)平均值為6.2 cm，最大均方根誤差為2.6 cm。

移動(dòng)接收器外形以及激光雷達(dá)掃描外殼獲得的點(diǎn)云數(shù)量直接影響基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)的定位精度，因此后續(xù)將從大尺寸圓形外殼激光接收器設(shè)計(jì)、高頻率點(diǎn)云激光雷達(dá)選用以及與慣性傳感器融合算法等方面開展研究，進(jìn)一步提高定位精度和環(huán)境適應(yīng)能力。

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Agricultural robot positioning system based on laser sensing

HU Lian1,2, WANG Zhimin1, WANG Pei1,2※, HE Jie1,2, JIAO Jinkang1, WANG Chenyang1, LI Mingjin1

(1.,,,510642,; 2.,,525000,)

In order to solve the positioning problem of global navigation satellite system (GNSS) based robots and autonomous agricultural machinery, which is low accuracy or even unable to locate under the environment of weak or no satellite signals such as hangars and greenhouses. This research proposes an agricultural robot positioning system based on laser sensing. The system is designed by using two-dimensional laser scanner and laser receiver, which obtains the point cloud of the laser receiver on the robot through the scanning laser emitted by the two-dimensional laser scanner , and the laser receiver inductively scans by the laser scanner, the location of mobile laser receiver (i.e. agricultural robot) is obtained by fusing the time difference of laser scanning induction and the point cloud characteristics of mobile laser receiver. The agricultural robot positioning system based on laser sensing consists of mobile laser receiver, processor, fixed laser receiver and two-dimensional laser scanner. The mobile laser receiver and processor are installed on the robot, and the fixed laser receiver and two-dimensional laser radar are fixed at the known geodetic coordinate position. According to the position relationship between the laser scanner coordinate system and the known geodetic coordinate system. The laser scanner scanning at a certain period to obtain a known number of fixed-order point cloud data. The fixed laser receiver senses the periodic irradiation of the laser scanner to generate the base station laser signal, and the serial number of the fixed laser receiver shell in the point cloud is known. The mobile laser receiver senses the periodic irradiation of the laser radar to generate the mobile laser signal during the movement of the robot. According to the trigger time difference between the fixed laser signal and the mobile laser signal, the angle between the laser rays that are irradiated to the mobile laser receiver and the laser rays that are irradiated to the fixed laser receiver can be obtained in a scanning period of the laser scanner. And the scattered point set of the mobile laser receiver in the laser radar point cloud can be found, and the center coordinate of the mobile laser receiver can be obtained by combining the point cloud feature matching algorithm. The robot positioning can be calculated by combined with the geodetic coordinates of the laser scanner and the position relationship between the laser scanner coordinate system and the geodetic coordinate system, the central coordinates of the mobile laser receiver under the geodetic coordinate system. The geodetic coordinates of the robot are calculated by the positioning algorithm based on laser sensing, and the geodetic coordinates of the robot without GNSS signal are supplemented without changing the positioning solution and control algorithm of the existing robot unmanned system. For example, when the robot leaves the hangar, it switches to the GNSS positioning system for positioning and navigation in the area with both the positioning signals of the robot positioning system based on laser perception and the GNSS signal. When entering the hangar, switch to the robot positioning system based on laser sensing for positioning and navigation in the area cover with both the positioning signal of the robot positioning system based on laser perception and the GNSS signal. The verification test is carried out with the reference of total station which shows that within the scanning range of laser radar, when the robot is at a speed of 0.8 m/s, the absolute average value of the maximum deviation of the positioning error in a straight line is 4.1 cm, and the maximum root mean square error is 1.5 cm; when the robot driving on a curve, the absolute average value of the maximum deviation of positioning error is 6.2 cm , and the maximum root mean square error is 2.6 cm. The result shows that this method can achieve accurate robot positioning and meets the positioning accuracy requirements for automatic navigation of agricultural robots in agricultural machinery warehouses and other environments.

robot; laser radar; laser sensing; positioning; intelligent agricultural machinery equipment

10.11975/j.issn.1002-6819.202211144

S24; TP273

A

1002-6819(2023)-05-0001-07

胡煉，王志敏，汪沛，等. 基于激光感知的農(nóng)業(yè)機(jī)器人定位系統(tǒng)[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2023，39(5)：1-7.doi：10.11975/j.issn.1002-6819.202211144 http://www.tcsae.org

HU Lian, WANG Zhimin, WANG Pei, et al. Agricultural robot positioning system based on laser sensing[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2023, 39(5): 1-7. (in Chinese with English abstract) doi：10.11975/j.issn.1002-6819.202211144 http://www.tcsae.org

2022-11-14

2023-01-16

江蘇大學(xué)農(nóng)業(yè)裝備學(xué)部項(xiàng)目（NZXB20210106）；廣東省科技計(jì)劃項(xiàng)目（2021B1212040009）；佛山市科技創(chuàng)新項(xiàng)目（2120001008424）；國(guó)家現(xiàn)代農(nóng)業(yè)技術(shù)體系（CARS-13）

胡煉，博士，研究員，研究方向?yàn)橹悄苻r(nóng)機(jī)裝備和無(wú)人農(nóng)場(chǎng)。Email：lianhu@scau.edu.cn

汪沛，博士，講師，研究方向?yàn)檗r(nóng)業(yè)工程、精準(zhǔn)農(nóng)業(yè)研究。Email：wangpei@scau.edu.cn