面向纺织生产环境的移动机器人定位方法

Mobile robot positioning method in textile production environments

纺织行业的智能化、绿色化是“双碳”战略中必须进行升级的内容,移动机器人的大量应用将是未来趋势,但是各类纺机中的电动机、传动机构等在生产过程中产生的电磁环境不利于机器人定位。为解决上述问题,提出一种多传感器混合滤波方法,通过结合基于自适应蒙特卡洛定位(adaptive Mentcarto localization, AMCL)方法和无迹卡尔曼滤波(unscented Kalman filter, UKF)融合定位来保证定位的精度;将AMCL与轮式里程计、惯性导航、激光里程计结合使用,根据惯性导航数据对各传感器数据进行预处理减少误差的引入;并通过UKF滤波器进行局部姿态估计。最后,基于机器人操作系统(ROS)框架,利用Gazebo仿真软件构建无、有电磁干扰的纺织车间环境进行试验。结果表明:在无电磁干扰的仿真环境中,AMCL-UKF混合滤波算法定位精度相较于扩展卡尔曼(extended Kalman filter, EKF)融合定位算法、UKF融合定位算法,精度分别提升26.9%、26.0%。在有电磁干扰环境中引入误差减小36.7%。提出的定位方法能够有效提高移动机器人室内定位的精度,对于纺织生产电磁环境下具有较好的稳定性。

Objective The intellectualization and green production of textile industry are the contents that must be upgraded following the"double carbon"strategy,and the large number of applications of mobile robots will be a fact in the future.However,robot has not been widely used in the textile workshop,and most of the robot positioning method are based on the traditional magnetic signals such as conductor.With the expanding of the scale of production,scalability is not strong.The ground environment,textile machinery and textile workshop electromagnetic interference problem will have to be solved.Therefore,a multi-sensor hybrid filtering method is proposed.Method In order to solve the impact of physical environment in textile workshop,the Inertial Measurement Unit(IMU)sensor data carried by the robot was compared with other sensor data,and a data preprocessing model was established to reduce the impact of ground and electromagnetic on sensor data.According to the characteristics of each sensor,the data processed by LiDAR,IMU and wheel odometer were fused by UKF(Unscented Kalman Filter)filter,and the global pose estimated by AMCL(Adaptive Mentcarto Localization)meter was added to UKF to solve the problem of positioning failure caused by the initial value and abnormal data.Results The simulation environment of textile workshop with and without electromagnetic interference was constructed based on ROS operating system,and the algorithm proposed in this paper was compared with other algorithms.Under the condition of no electromagnetic interference,the positioning accuracy of single sensor was found to decrease significantly and even fail due to the influence of complex ground and similar environment in textile workshop(Fig.6).Compared with UKF and EKF multi-sensor fusion algorithms,AMCL-UKF algorithm demonstrated better fitness and stronger robustness in the face of complex environment in textile workshop.AMCL-UKF algorithm reduced the positioning error by 85.9%and 34.8%and the maximum positioning error was reduced by 8.1%and 7.6%,indicating that multi-sensor fusion could effectively improve the positioning accuracy(Tab.3).It showed that the multi-sensor algorithm could effectively reduce the error caused by EKF and UKF linearization process.In the environment with electromagnetic interference,as shown in Tab.4,the maximum error of the data preprocessing model was reduced by 32.5%,the average value reduced by 37.6%,the root means square error reduced by 36.7%,and the standard deviation reduced by 12.7%,proving the effectiveness of the method.The AMCL-UKF algorithm provided relatively accurate positioning accuracy and stability in the face of strong magnetic field interference in the textile workshop(Fig.11).Conclusion The experimental results show that the data preprocessing model can effectively reduce the influence of physical environment of textile workshop on sensor data.Through the AMCL algorithm,the global pose is calculated and input into the UKF filter,which can improve the positioning failure of the Kalman filter caused by the interference in the working process of the textile robot and improve the working stability.Problems such as electromagnetic interference,ground,and error introduction during collaborative work in textile workshop have limited influence on positioning accuracy.However,the proposed algorithm does not use data information interaction between multiple robots for collaborative positioning.The latest research method of robot positioning is graph-based optimization algorithm,which has higher positioning accuracy.Therefore,the future research direction is to improve the positioning accuracy through graph optimization algorithm by using mutual measurement between multiple robots and reduce the computational complexity of graph optimization algorithm to further improve the positioning accuracy of robots.In conclusion,the improved AMCL-UKF method in this paper can provide accurate positioning information for mobile robots and provide theoretical and experimental data support for mobile robot application schemes required for intelligent upgrading of textile workshops in the future.