Accurate visual positioning and orienting method for rotor wing unmanned aerial vehicle

The invention discloses an accurate visual positioning and orienting method for a rotor wing unmanned aerial vehicle on the basis of an artificial marker. The accurate visual positioning and orienting method includes the following steps that the marker with a special pattern is installed on the surface of an artificial facility or the surface of a natural object; a camera is calibrated; the proportion mapping relation among the actual size of the marker, the relative distance between the marker and the camera and the size, in camera imaging, of the marker is set up, and the keeping distance between the unmanned aerial vehicle and the marker is set; the unmanned aerial vehicle is guided to fly to the position where the unmanned aerial vehicle is to be suspended, the unmanned aerial vehicle is adjusted so that the marker pattern can enter the visual field of the camera, and a visual recognition function is started; a visual processing computer compares the geometrical characteristic of the pattern shot currently and a standard pattern through visual analysis to obtain difference and transmits the difference to a flight control computer to generate a control law so that the unmanned aerial vehicle can be adjusted to eliminate the deviation of the position, the height and the course, and accurate positioning and orienting suspension is achieved. The accurate visual positioning and orienting method is high in independence, good in stability, high in reliability and beneficial for safety operation, nearby the artificial facility the natural object, of the unmanned aerial vehicle.