Visual navigation algorithm for asteroid lander based on irregular curve matching

In order to solve the visual navigation problem of the landing process of the small celestial body lander, this paper proposes an algorithm to estimate the position and attitude of the lander by using point-tangent line on the irregular curve. First, the irregular curve matching in the landing image is completed by constructing the irregular curve descriptor. Second, the constraint relationship between the position attitude and the point-tangent is established. Then, the curve parameterization method is used to solve the higher order equations, and the constraint conditions are used to obtain the unique solution of position attitude parameters and the least squares solution of multiple matching curves. Finally, the influence of noise intensity and the number of matching curves on the navigation accuracy is verified by simulation, and the feasibility of the algorithm is proved.