基于三次样条插值实现无人机高动态运动轨迹插值

3D-coordinate interpolation for UAV high dynamic positioning based on cubic spline interpolation

差分全球卫星导航系统(GNSS)技术辅助空中三角测量技术可实现无人机影像元素的高精度绝对定位.机载GNSS模块采样频率一般不超过50 Hz,更高的采样频率对GNSS模块软硬件提出更高的要求.本文基于三次样条函数实现无人机高动态定位的三维坐标插值,并通过实测数据检验三次样条函数的适用性,实验结果表明,固支样条更适用于无人机高动态运动轨迹坐标插值,当采样频率高于5 Hz时,平面插值精度优于1.0 cm,高程插值精度优于2.2 cm.

Aerial triangulation, assisted by differential GNSS, is essential part of precise positioning of UAV image elements. As the sampling frequency of GNSS module usually does not exceed 50 Hz, higher sampling frequency would be a serious problem for software and hardware of UAV. In this paper, 3 D-coordinate interpolation for high dynamic positioning of UAV is realized based on cubic spline interpolation approach, whose applicability has been tested by real measurements. The experimental results show that clamped spline is more suitable for high dynamic interpolation of UAV. When the sampling frequency is higher than 5 Hz, plane interpolation accuracy is better than 1 cm and elevation interpolation is better than 2.2 cm.