Application of Double GPS Multi-rotor UAV in the Investigation of High Slope Perilous Rock-Mass in An Open Pit Iron Mine

In the survey of high slope perilous rock-mass in open-pit iron mine, the traditional unmanned aerial vehicle (UAV) can overcome the shortcomings of high difficulty and high risk factor in artificial geological exploration. However, it is very easy to be disturbed by the magnetic field of iron ore due to its orientation with magnetic compass, which makes the work unable to carry out normally. In order to solve the above problems, the UAV with dual-GPS equipped with laser radar can resist the magnetic field interference to a large extent and scan the high slope. By means of field experiment and point cloud data post-progressing, a set of application method of dual GPS multi-rotor UAV laser measurement technology was proposed for geological survey of high slope perilous rock under the interference of magnetic field. The preliminary conclusions are also obtained: the dual GPS combined orientation method makes the multi-rotor UAV not affected by the iron ore magnetic field and can fly normally according to the flight route. At the same time, the airborne LiDAR technology can realize the long-distance and fast acquisition of the valid terrain data of high-slope dangerous rock mass. Through the fuzzy clustering method (FCM), the joint system of outcrop rock-mass is automatically recognized and categorized based on point cloud data captured. The plane normal vector of fitting structural surface and structural surface occurrence can then be acquired. The normal vector of structural surface and the occurrence of structural surface can be obtained by substituting calculation. The occurrence of the slope and the shape of the structural surface was further drew into the stereographic projection map in order to determine the dominant joint group which affects rock slope stability.