联合船载单波束潮间带机载LiDAR测量系统

Intertidal zone measurement combined shipborne single beam bathymetry with airborne LiDAR system

潮间带地形测量对保护与利用滩涂具有基础作用,本文提出联合船载单波束回声测量与机载激光LiDAR综合系统。首先采用ODOM MKⅢ双频单波束测深仪同步采集并验证无人机机载LiDAR潮间带范围点云成果符合精度;然后针对潮间带复杂环境设计了无人机机载LiDAR低潮航摄关键指标;最后优化了高精度大比例尺地形图测制方法,该方法结合了低潮时机载LiDAR滩涂陆地地形和高潮时船载单波束测深滩涂水下地形方式的潮间带。实践表明:(1)选取的816个重合区域测点高程比对测量符合精度,99%的比对点高程差值在0.2 m内,说明机载激光LiDAR测量可满足沿海滩涂测量要求;(2)无人机进出测区应依次轮换,且采用平飞结合八字飞行以避免IMU误差累积,控制航线弯曲度不大于3%,保障点云数据精度及有效覆盖;(3)该测量系统在潮间带高精度大范围地形测量工程具有参考意义。

Intertidal topographic surveys have a fundamental role in the protection and utilization of tidal flats. A combined shipborne single beam bathymetry echo measurement and airborne laser LiDAR integrated system is proposed. Firstly, the ODOM MKⅢ dual-frequency single beam bathymetry is used to collect and verify the accuracy of the point cloud results in the intertidal zone of the UAV airborne LiDAR. Then the key indicators for the implementation of UAV airborne LiDAR low-tide aerial photography are designed in complex environments. Finally the intertidal zone with high precision is optimized by combining the land topography of airborne LiDAR tidal flats at low tide and the underwater terrain of tidal flats with shipborne single beam bathymetry at high tide. Scale topographic map surveying method. The practice shows that:(1) 816 measuring points in the overlapping area are selected to compare the two measurement accuracies, and 99% of the compared points have the difference in elevation within 0.2 m, indicating that the airborne laser LiDAR measurement can meet the measurement requirements of coastal tidal flats.(2) The UAV entering and leaving the survey area should be rotated in turn, and the horizontal flight combined with the figure-of-eight flight should be used to avoid the accumulation of IMU errors.(3) The measurement system is of reference significance for the promotion of high-precision large-area topographic surveying projects in the intertidal zone.