A Vision Navigation Algorithm for MAVs Attitude Estimation Based on Radon Transformation

Utilizing the horizon in the nature, the navigation parameters for Micro air vehicles (MAVs) stabilization can be calculated by using the method of image processing. In this paper, a method based on Radon transformation is proposed to detect the horizon. After determining the linear equation of the horizon, the roll angle can be calculated by the slope of the linear equation. The pitch angle can be measured by a method of "pitch distance" proposed in the paper. The proposed method makes full use of the edge information. Therefore, it can detect the horizon accurately without being confused by the barrier above the ground. Comparing with the method using sky area ratio, the method using "pitch distance" can reflect the real changes of pitch angle by means of eliminating the effect of roll angle. Theoretical analysis and experimental results demonstrate that the vision navigation algorithm is accurate and reasonable.