Location estimation method based on circular target by UAV’s monocular

In order to solve the difficulties in location estimation of practical applications such as real-time tracking and formation coordination in large space, large-scale scene, we proposes a method for location estimation based on monocular vision and circular markers whose diameter is known on the UAV platform.We analyzed the circular center offset in the perspective projection, and gave the correct formula for the center offset. Then the effectiveness of circle center estimation algorithms and location estimation is verified by fixed camera with different tilt angle $\theta$ and monocular on UAV. We used the monocular vision based on the UAV to achieve the location estimation with an accuracy of 3.0cm.