连栋温室分段变距喷雾机器人设计与试验

Design and Experiment of Segmented and Variable Distance Spraying Robot for Multi-span Greenhouse

针对国内连栋温室缺乏植保喷雾机、机械走直定位与换轨转向精度低等问题,设计了一种连栋温室分段变距喷雾机器人,在实现无人化喷药的同时提高作业精度。为满足连栋温室机械作业路轨结合、精准切换的要求,提出一种通用型移动底盘,并确定其关键设计参数;为减少底盘上下轨时的偏移量,设计轨上矫正装置,通过分析计算及试验验证,确定其安装余量为4 mm;针对底盘对轨误差大的问题,提出一种二维码融合陀螺仪及光电传感器双向垂直寻迹的路面关键点定位与转向控制方法。设计分段变距喷雾装置,提出一种丝杆滑台驱动的喷杆变距方案,分析校验其驱动参数以满足工作要求;基于滚针轴承设计喷杆辅助防抖装置,减小因喷杆剧烈抖动带来的滑台与喷杆损伤。开发底盘运动及分段变距喷雾控制系统,实现喷雾机器人在连栋温室内的全程自动化作业。最后,对样机进行底盘性能与喷雾效果试验。底盘作业时直线行走与对轨误差平均值分别为4.8、5.8 mm,满足控制精度要求;避障距离为34 cm,满足安全性要求;防抖装置的安装使喷杆行进方向的抖动量从-1°~1.3°降低到±0.4°内,喷头方向的抖动量从±0.5°降低到±0.3°内,防抖效果显著;分段变距喷雾作业后,盛果期番茄叶片正面雾滴沉积量为1.76μL/cm^(2),反面沉积量为0.2μL/cm^(2),雾滴体积中径在100~180μm之间,满足作业要求。

In response to the lack of connected greenhouse plant protection spraying machines,low precision in mechanical straight-line positioning and rail switching,a segmented and variable distance spraying robot was designed for multi-span greenhouses to achieve unmanned spraying while improving operational precision.To meet the requirements of combining road and track operation and precise switching for mechanical operations in multi-span greenhouses,a universal mobile chassis was proposed with its key design parameters determined.To reduce deviations during chassis movement along the upper and lower rails,a rail correction device was designed.Through analysis,calculations,and experimental validation,an installation clearance of 4 mm was established as suitable.Considering the significant chassis tracking errors,a road surface key point positioning and steering control method combining QR codes,gyroscopes,and photoelectric sensors was proposed.The design of the segmented and variable distance spraying device involved proposing a screw slide table-driven spray boom with variable-distance capabilities.The driving parameters were analyzed and validated to meet the operational requirements.Additionally,an auxiliary anti-vibration device based on roller bearings was developed to reduce damage caused by severe vibration of the spray rod.The chassis motion and segmented and variable distance spraying control system were developed to enable full automation of the spraying robot within multi-span greenhouses.Finally,performance and spray effect tests were conducted on the prototype,yielding the following results:the average straight-line travel error and tracking error of the chassis were 4.8 mm and 5.8 mm,respectively,meeting the requirements for control precision.The obstacle avoidance distance was 34 cm,ensuring safety.The installation of the anti-vibration device reduced the vibration in the travel direction of the spray rod from-1°to 1.3°to within±0.4°and limited the vibration in the nozzle direction from±0.5°to within±0.3°,demonstrating significant improvement in anti-vibration effectiveness.Following segmented and variable distance spraying,the deposition of mist droplets on the front surface of tomato leaves during the fruiting stage was approximately 1.76μL/cm2,while the back surface achieved approximately 0.2μL/cm2 of deposition.The mist droplet volume median diameter ranged from 100μm to 180μm,meeting the operational requirements.