机载三线阵影像空中三角测量的关键问题

Key issues on the triangulation of airborne three line array images

对机载三线阵影像空中三角测量中涉及的平差数学模型、GPS/IMU的系统误差补偿、对地面控制点的需求以及构架航线的影响四个关键技术问题进行了理论分析与实验验证。ADS40数据的实验结果表明,GPS/IMU的定位误差是系统性的,并主要表现在坐标基准的不同。通过设计适当的数学模型改正GPS/IMU的系统误差,利用低阶多项式或定向片平差,在极少量地面控制点支持下即可达到1个像素左右的定位精度。构架航线对平差结果的改善作用有限,实际作业中不建议采用。

This paper gives theoretic analysis and experimental demonstration Of four key issues on the triangulation of airborne three line array images, including the mathematical model, the compensation of GPS/IMU systematic error, the requirement of ground control points and the influence of cross strips. Test results from ADS40 data show that the positioning error of GPS/IMU unit is systematic, and behaves as different datum. By setting up proper mathematic model to compensate the systematic error of GPS/IMU data, triangulation with lower order polynomial or orientation image method can achieve the accuracy of about one pixel when few ground control points are introduced. Cross strips do less good to the bundle adjustment, so not recommended for actual task.