To achieve exact positioning and control of the rotor flying robot in indoor environments, an onboard visual positioning (OVP) method based on monocular vision is designed. It can recognize landmark images by moment feature extraction and image classification, and calculate camera coordinates through EPnP method. To verify the effectiveness of the proposed onboard visual positioning method, an external visual positioning system (EPVS) based on Kinect is built, and a visual tracking algorithm for rotorcraft is designed. The experimental results suggest that the positioning deviation of the rotorcraft is within 2 mm, and the OVP method is suitable for rotorcraft positioning.
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