基于测距值修正的温室植保机器人定位方法

Positioning Method of Greenhouse Plant Protection Robot Based on Distance Measurement Value Correction

针对温室植保机器人作业过程中,UWB节点之间频繁出现的非视距通信现象导致UWB系统定位精度低和稳定性差的问题,提出了一种基于UWB测距值修正的融合定位方法。首先,设计了基于测距残差的UWB节点间通信类型识别方法;其次,分析了视距和非视距通信下UWB测距误差产生原因并建立了两种通信条件下的测距值修正模型;最后,基于扩展卡尔曼滤波器设计了UWB测距修正值和IMU数据融合方法,实现了温室机器人作业过程中的可靠定位。在温室环境下的实际验证结果表明:非视距通信条件下,经过UWB测距修正的融合定位方法的定位误差为11.95 cm,相较于未进行UWB测距值修正的融合定位方法,定位误差降低83.11%,可为温室植保机器人提供稳定的高精度定位信息。

A fusion positioning method was proposed based on the correction of UWB distance values to address the problem of low positioning accuracy and poor stability of UWB systems caused by frequent non-visual communication between UWB nodes during the operation of greenhouse plant protection robots.Firstly,a method to identify the communication type between UWB nodes was designed based on the distance residuals;secondly,it analyzed the causes of UWB distance errors under line-of-sight and non-line-of-sight communication and established a distance correction model under the two communication conditions;finally,it designed a method to fuse UWB distance correction values and IMU data based on the extended Kalman filter,and achieved reliable positioning during the operation of greenhouse robots.Finally,the UWB distance correction and IMU data fusion method were designed based on the extended Kalman filter,which finally realized the reliable positioning during the operation of greenhouse robot.The actual validation results showed that the positioning error of the fusion method with UWB range correction was 11.95 cm under the non-line-of-sight communication conditions,which was 83.11% lower than that of the fusion method without UWB range correction,and it can provide stable and high-precision positioning information for the greenhouse plant protection robot.