基于无人机飞行平台的定位与测姿系统(Position and oricntation system, POS)是通过差分GNSS高精度定位技术与INS导航技术集成, 为基于直接地理参考的航空遥感提供位置和姿态基准, 是获取高质量遥感成像的关键。针对轻小型无人机采用的低精度IMU, 对其误差模型展开研究分析, 建立24阶卡尔曼滤波器, 最后采用GNSS/INS松组合模式得到高精度POS数据。实测数据表明, 将此误差模型下获取的POS数据与无人机激光雷达扫描数据进行融合处理, 可满足激光点云精度需求, 有效降低机载激光扫描系统成本。

Positioning and orientation system (POS) based on UAV platform is integrated with differential GNSS high-precision positioning technology and INS navigation technology to provide position and attitude reference for aerial remote sensing based on direct geo-reference. It is the key to obtain high-quality remote sensing imaging. Aiming at the low-precision IMU adopted by the light and small UAV, the error model is researched and analyzed, and the 24th-order Kalman filter is established. Finally, the GNSS/INS loose combination mode is used to obtain high-precision POS data. The measured data shows that the POS data obtained under this error model can be combined with the radar data of the UAV to meet the laser point cloud accuracy requirements and effectively reduce the cost of the airborne laser scanning system.