Relative Position Calculation Based on Near-infrared for Autonomous Aerial Refueling

In the probe and drogue docking process for the unmanned aerial vehicle(UAV)aerial refueling,an autonomous, all-time,all-weather and high-precision relative position calculation technology is needed.Because of nearinfrared images have the advantages of high resolution and the ability of anti-environmental interference,a near-infrared relative position calculation method is presented for the UAV aerial hose refueling.Relative position calculation system based on the vision is constituted with four 850 nm band near-infrared LED lights arranged uniformly in inner ring of the drogue,the 850 nm band-pass filter and the Logitech C310 camera.Firstly the near-infrared images of the drogue is got.Then the drogue is detected by the threshold segmentation,feature points detection and the circle fitting algorithm.Finally relative position between the probe and drogue is calculated.Performance of the algorithm is verified by experiments under different weather conditions,different angles and different distances.Finally,the scope of application of the algorithm is given to provide a reference for engineering applications.