自适应视觉惯性地磁紧耦合定位系统
Adaptive visual inertial geomagnetic tightly coupled positioning system
付鹏 1万振华 2王琨锋 3赵开春3
作者信息
- 1. 清华大学 精密仪器系,北京 100084;北京信息科技大学 仪器科学与光电工程学院,北京 100192
- 2. 广西大学 机械工程学院,广西 南宁 530004
- 3. 清华大学 精密仪器系,北京 100084
- 折叠
摘要
为了解决视觉惯性组合导航系统绝对航向信息缺失与姿态发散的问题,进一步提升系统定位精度,设计并实现了针对未知磁场环境下的自适应视觉惯性地磁紧耦合定位系统.基于常用的三轴磁力计内外参数联合标定原理,提出了一种地磁信息全局及帧间约束残差构建方法.通过磁强度差异动态调整融合权重,利用非线性优化方法设计视觉/惯性/地磁紧耦合系统实现自身运动状态估计.最后,在校园环境下开展户外实验.实验结果表明:该系统能够在部分建筑及车辆磁场干扰环境下稳定运行,定位精度均优于0.8%(RMSE),相比于VINS位置误差平均降低了约24%,且具有良好的实时性.磁力计及自适应融合方法的引入可以有效改善现有视觉惯性导航系统的定位性能,为无人系统提供高可靠性的实时定位结果.
Abstract
To solve the problem of missing absolute heading data and attitude drift in the visual-inertial navigation system,and to enhance its positioning accuracy,an adaptive visual-inertial-geomagnetic tightly integrated positioning system was developed for environments with unknown magnetic fields.Initially,the calibration process for the internal and external parameters of standard tri-axis magnetometers is detailed.Following this,a strategy for generating global and frame-to-frame constrained residuals from geomagnetic data is outlined.The system dynamically adjusts fusion weights based on variations in magnetic intensity and employs a nonlinear optimization approach for the visual-inertial-geomagnetic integration to estimate its motion state accurately.Outdoor tests conducted on a university campus demonstrated that the system remains stable amidst magnetic disturbances from buildings and vehicles,achieving positioning accuracy better than 0.8%(RMSE).When compared to VINS,this system reduces position error by an average of 24%,showcasing impressive real-time capabilities.Incorporating magnetometers and adaptive fusion tech-niques significantly boosts the performance of existing visual-inertial navigation systems,offering reliable real-time positioning for autonomous systems.
关键词
组合导航/地磁场/自适应系统/非线性优化Key words
integrated navigation/geomagnetic field/adaptive system/nonlinear optimization引用本文复制引用
基金项目
教育部联合基金资助项目(6141A02022606)
出版年
2024
国家科技期刊平台
NSTL
万方数据