摘要
天空偏振光场定位技术凭借全自主、抗干扰及无累积误差特性,为无卫星信号场景下定位提供了新型解决方案。针对目前成像式偏振定位装置较多采用鱼眼镜头,需要复杂的全视场标定,且存在偏振效应的问题,设计并实现了一种基于镜面反射的定位装置,并采用神经网络方法对定位装置的误差进行了补偿。该装置由偏振相机、小视场镜头、多个反射镜和寻北仪构成。测量时,天空中的散射光先照射到反射镜,产生反射光,之后经过小视场镜头照射到偏振相机的感光器件。建立了从反射光的偏振态解算入射光偏振态的模型,基于该模型,定位装置可以根据每个观测点入射光的偏振态计算太阳矢量,再结合天文年历和时间信息,最终实现地理定位功能。此外,采用神经网络模型对系统误差进行了误差补偿。室外静态实验表明,经度和纬度定位的均方根误差分别为0.259 6°和0.336 2°,最大误差不超过0.6°,在无卫星信号的情况下,能够提供实时稳定的地理定位信息。
Sky polarization field positioning technology,characterized by full autonomy,anti-interference capability,and no cumulative error,offers a novel solution for positioning in situations without satellite signals.To address the issues in current imaging-based polarization positioning devices,which often use fisheye lenses requiring complex full-field calibration and suffer from polarization effects,a positioning device based on specular reflection is designed and implemented with system errors compensated using a neural network approach.The device consists of a polarization camera,a narrow-field lens,multiple mirrors,and a north-seeking instrument.During measurement,scattered light from the sky first strikes the mirrors,generating reflected light,which then passes through the narrow-field lens before reaching the image sensor of the polarization camera.A model is established to derive the polarization state of the incident light from the polarization state of the reflected light.Based on this model,the device calculates the solar vector from the polarization state of the incident light at each observation point and,in combination with astronomical almanac and time information,achieves geolocation functionality.Additionally,a neural network model is employed to compensate for system errors.Outdoor static experiments show that the root mean square errors for longitude and latitude positioning are 0.2596°and 0.3362°,respectively,with a maximum error not exceeding 0.6°.The results demonstrate that the system can provide realtime and stable geographic positioning information in the absence of satellite signals.
作者
张宇衡
褚金奎
王寅龙
ZHANG Yu-heng;CHU Jin-kui;WANG Yin-long(College of Mechanical Engineering,Dalian University of Technology,Dalian 116024,China;Ningbo Institute of Dalian University of Technology,Ningbo 315032,China)
出处
《光学与光电技术》
2025年第6期130-141,共12页
Optics & Optoelectronic Technology
关键词
天空偏振光
地理定位
镜面反射
神经网络
误差补偿
sky polarization
geolocation
specular reflection
neural network
error compensation
